BHD Community Symposium 2022 Report – Connecting the Community  

The 2022 BHD Community Symposium took place virtually on October 8th. We were delighted to have over 200 people registered from across the world. The symposium was designed to connect people with shared experiences of Birt-Hogg-Dubé syndrome (BHD) and break down the barriers between patients, researchers and clinicians. It was an opportunity to learn from one another and drive forward BHD research.

Connecting with the Experts

Our Meet the Experts session facilitated discussion around the symptoms of BHD. We had three ‘rooms’ dedicated to lung, skin and kidney symptoms. Each room had at least two BHD experts. They provided a platform where patients, researchers and doctors could talk about treating and monitoring the symptoms of BHD.  


In the kidney session, we were joined by Consultant Urological Surgeon Mr Rupesh Bhatt (UK) and research scientist Dr Laura Schmidt (USA). Much of the discussion focused on kidney screening in BHD, which currently has no formal guidelines. Both experts agreed that kidney screening should start in early adulthood. They advised against only having CT scans. This is because CT scans use radiation. Instead, the experts recommended MRI scans or ultrasound scans. The frequency of the scans depends on the type of scan being used and whether a person has a tumour. They also explained that as BHD tumours are usually slow growing any kidney tumour detected should be monitored and removed if it reaches 3cm.


In the lung session, we were joined by Professor Lisa Henske (USA), Professor Nishant Gupta (USA) and Professor Stefan Marciniak (UK). A range of topics were discussed covering many aspects of lung cysts and collapsed lungs. It was queried if lung cysts change over time in BHD. The experts thought there wasn’t much change in BHD, but that this data comes from small numbers of people over relatively short time frames. More work needs to be done to confidently answer this question.

One common question that comes up often is concerning certain activities such as flying or diving with BHD. The risk of having a collapsed lung in BHD is thought to be less than 1 per 100 flights. The risk is thought to be the same for diving, however there is less confidence in this number due to the low numbers reported. The presence of lung cysts is not a reason to avoid flying or diving. However, if you have the symptoms of a collapsed lung, you should not fly or dive.


We were joined by Professor Joyce Teng (USA) and Dr Ed Cowen (USA) for a fascinating session on the skin.

The session started with a discussion surrounding the incidence of skin bumps (fibrofolliculomas) in the BHD population. This can be age-related, and may explain a lot of the delayed diagnoses seen. However, fibrofolliculomas are thought to only occur in BHD. Therefore, if a biopsy is taken this should be a clear indication of BHD.

The impact of skin bumps on well-being was discussed, with various treatment options outlined. None of the current treatments provide a permanent solution as the skin bumps will return after treatment. However, people have had relative success with various treatments. Due to BHD being a rare condition, with little evidence on these treatments, there are no official guidelines as of yet regarding the most effective treatment.

Connecting with the community

As BHD is a rare condition it is unlikely that your family, friends or even your doctor have heard of it. We know that this can feel lonely. The BHD Foundation is trying to change this by raising awareness and bringing people together through events such as the symposium.

“…there was comfort in participating with a community of individuals facing similar issues as myself. It definitely provided a level of ‘assurance’ that we are not alone in this!” Feedback from BHD community symposium attendee.

In our final session, Bob, Julia and Barnaby shared their personal BHD stories. Although each had different symptoms, there were many similarities between them. This included the challenge of reaching a correct diagnosis. Two of the panel members were doctors and they described how they had never heard of BHD before their diagnosis.  They suggested that although doctors cannot know all 7000+ rare diseases, there should be a ‘collaborative effort between patient and physician to educate each other’.

“I liked that there were specialists in all aspects of BHD, especially that there were physicians who were also BHD patients like the rest of us.” – Feedback from BHD community symposium attendee

Another common theme of this session was how to discuss BHD with family members and things to consider around genetic testing. This included the effects on mental health, access to insurance and changes to lifestyle. As having BHD leads to a change in medical care (regular kidney scans) it was felt that informing family members is important. However, whether to get tested is an individual’s choice.

It was wonderful to see the community coming together with a common goal of raising awareness and advancing research into BHD. Through sharing stories and experiences, we can learn from one another and identify the areas of research that are needed to advance our understanding of BHD and ultimately find a cure.

We look forward to seeing you at next year’s research-focused conference. We are delighted to announce that it will be a hybrid event, so everyone can take part. It will be held both online and in London, UK.

Read part 1 of the BHD Community symposium report to find out about the current research into BHD.  

BHD Community Symposium 2022 Report – Research

The first BHD Community Symposium was held on October 8th, 2022. We were delighted to have over 200 people registered from 22 countries across 5 continents for this virtual event. This year’s symposium was the first deliberately designed to be accessible to all members of the community throughout the entire event. We were thrilled to welcome people with Birt-Hogg-Dubé syndrome (BHD) and their families alongside clinicians and researchers.

There were a range of sessions from the latest research to a Q&A with BHD experts. We also held a session with members of the BHD community sharing their personal BHD stories. The opening talk featured our CEO, Anna Webb, in conversation with Sue Sherman, Director and CEO of the LAM Foundation. They spoke about the shared challenges faced by communities in the rare disease space and the importance of the patient voice when tackling them.

…it’s the voices, as we know, of our communities that really are vital to the progress of both research as well as improving treatment from rare diseases.” Sue Sherman

Raising awareness, connecting the community and inspiring the next generation of scientists were topics for discussion. There are so many things we can learn from other rare communities, but it is important to remember we are not alone. We need to work with other advocacy organisations such as the LAM Foundation to build our network and drive change. This conversation was a positive and inspiring way to start the symposium and we are extremely grateful to Sue for joining us.

BHD Research Updates

There were several sessions dedicated to the latest BHD research. To kickstart this session, we heard from Julia Thierauf, BHD community member, clinician and researcher. She gave an overview of the scientific process and how research works. Following on from this, we heard from some of our 2021 grant holders as well as researchers from around the world.

Understanding BHD

Many talks were focused around better understanding BHD as a condition and how it affects people. Bryndis Yngvadottir (UK) gave us an update on their work trying to better estimate the prevalence of BHD. BHD is associated with variations in the gene folliculin (FLCN). Looking at how many people have a FLCN variant can help us work out how common BHD is. Rates from the literature vary from around 1 in 3000 people to 1 in 500,000 people. The work presented here, looking at the 100,000 genomes project suggested that the prevalence of BHD may be closer to the 1 in 3000 people estimate.

Lore van Riel (The Netherlands) presented the need to raise awareness of BHD among doctors to improve diagnosis. BHD is the most common genetic cause of a collapsed lung. In people that have a collapsed lung for no obvious reason, BHD should be considered, especially if there is a family history. We also heard from Ortrud Steinlein (Germany) about the delay between first symptom appearance and diagnosis in BHD. We recently blogged about her work and how gender might affect diagnosis.

Liu Jie discussed their work in China to improve BHD diagnosis. They found the most common symptom was a collapsed lung. Very few people had symptoms in the skin or kidney. However, another study from a rare lung clinic in China showed a higher number of people with skin symptoms. More work needs to be done to understand any difference in symptoms between different ethnicities. A talk from Fiona Bruinsma (Australia), looked at the proportion of people with each symptom of BHD. They found that by age 70, over 9 in 10 people had symptoms in the skin and/or lungs.

Together, these projects will help us better understand how people are affected by BHD and inform diagnosis and management pathways.

Understanding Folliculin

It is vital to understand the cellular biology behind BHD. There is a lot of work being done to understand the biology of FLCN and how a loss of FLCN leads to the symptoms seen in BHD.

We heard from Ryosuke Jikuya (Japan) and Ye Yang (USA) who are both using state-of-the-art methods to look at kidney cancer in BHD at the molecular level. Their work will help us understand more about how kidney cancer develops and grows. It will pave the way for future work to develop new therapies for BHD-related kidney cancer. 

Damir Khabibullin (USA) spoke about their work looking at FLCN in the lung. Their data shows that loss of FLCN in lung cells called mesenchymal cells led to the formation of lung cysts. Understanding how lung cysts form could help inform future treatments for the lung.

Rob Wolthuis (The Netherlands) presented research identifying a new BHD-like syndrome. Their work identified the gene responsible for this new syndrome and found that it was a regulator of FLCN protein. This work expands our knowledge of how FLCN works in our cells as well as identifying a new condition related to BHD.


Research was also presented on the treatment of BHD-related kidney cancer. Currently, the standard treatment is for any tumours to be removed by surgery when they reach 3 cm. However, there are some situations where surgery may not be appropriate. Sylvain Bodard (France) presented their work using a technique called percutaneous thermal ablation for the treatment of kidney cancer. They found this to be a safe and effective treatment for BHD-related kidney cancer.

We also heard from Dustin Armstrong (USA) who spoke about a new drug that may have benefit in treating BHD-related kidney cancer. This drug has already been tested in another condition called Pompe disease and has been found to be safe. They are now interested in pursuing research and collaborations to test their drug in BHD.


It is exciting to see the breadth and depth of research happening around the world into BHD. We were thrilled to be able to bring this research to the entire BHD community.

“The research talks were fascinating, highly informative and gives us all a lot of hope that significant advances are being made towards finding a cure and towards optimal management of BHD.”  Feedback from BHD Community Symposium attendee

Connecting all parts of the community is at the heart of the BHD Foundation. There is so much we can learn from each other, and it was heart-warming to be able to share different perspectives.

“I am getting to see patient perspectives for the first time, and simultaneously saw great cutting-edge research results. This leaves me with a lot of hope that we will one day soon be able to treat all patients efficiently, successfully with minimal invasive procedures.”  Feedback from BHD Community Symposium attendee

Our blog post next week will round-up our BHD Community Symposium report, focusing on the ‘Meet the Expert’ and ‘BHD and Me’ sessions.

If you registered for the event but couldn’t attend on the day, a recording of the event will be sent as soon as it is available. You can also still take part in the BHD raffle that was launched at the symposium. To receive the latest updates about events, sign up to our newsletter.

The BHD Syndrome International Registry – 6 Month Update

What is BIRT?

The BHD Syndrome International Registry (BIRT) is a patient registry that collects information on the diagnosis, symptoms and management of Birt-Hogg-Dubé syndrome (BHD). The overall mission of BIRT is to improve the quality of life of those living with BHD. We hope to achieve this through collecting data that will allow a consensus on diagnosis and management guidelines to be produced. Diagnosing BHD early is important to ensure that the condition is managed so that any kidney cancer is caught as early as possible.

However, for BIRT to be a success, we need as many people as possible to get involved. One of the major problems that slows down research into rare conditions is the lack of data. Through BIRT, we can provide that data to researchers to help them answer so many of the unknown questions about BHD. This is a chance for the community to come together to drive forward and speed up research into BHD.

Find out how to get involved below.

Who is currently involved in the registry?

There are currently 173 people registered from 18 countries around the world. Around 2 thirds of people registered are female and one third are male. However, we know that gender doesn’t affect who gets BHD. Therefore, we encourage you to spread the word to your family members so that they can get involved. Most people are aged between 55 and 60, however this ranges from age 20 to 85. You can also sign up on behalf of someone and complete their information by proxy.

What do we know so far?


On average, people are diagnosed with BHD at age 44. However, the average age of first symptom is 30 years. This represents a huge gap between symptom and diagnosis. It also shows why we need more awareness of BHD to speed up diagnosis. Participants also reported the first time they contacted health services regarding symptoms of diagnosis of BHD. The average for this was 43 years. This suggests that people aren’t contacting their healthcare providers upon the first symptom of BHD. However, there are some caveats to this data. The main one being that this information is self-reported, and individuals may not have access to accurate health records. For example, one of the most commonly reported first symptoms is a collapsed lung (see below). It is likely that most people with a collapsed lung will have sought medical attention immediately. In the future, we plan to include clinician-reported data which will help establish the causes for the delay to diagnosis.

First Symptoms Reported

1. Fibrofolliculomas or other skin bumps (around 5 in 10 people)
2. Collapsed lung (around 4 in 10 people)
3. Kidney cancer or ‘Other’ symptom (around 1 in 10 people)


  • Around 8 in 10 people reported skin bumps
  • Around 7 in 10 people reported lung cysts
  • Around 5 in 10 people reported having a collapsed lung
  • Around 3 in 20 people reported having kidney cancer

This data is fairly consistent with the current literature on the proportion of people with each symptom. There are slightly more people reporting a collapsed lung and fewer people reporting kidney cancer. However, the average age of onset of kidney cancer is later than the other symptoms and so this data may change as people update the registry. This is one of the benefits of a patient registry – the ability to track how a condition affects a person over time.


15 out of 62 people had treatment for their fibrofolliculomas. However, 13 out of 15 people reported recurrence of their skin bumps. Currently, there are only treatments available to remove skin bumps. There is no treatment to prevent new ones from forming.

41 out of 101 people had treatment for their lungs. The most common type of treatment was a pleurodesis (31 people), followed by a chest drain (10 people). The pleurodesis was done as a preventative measure in 11 people. Of the people who received treatment, 9 reported having a collapsed lung (in the same lung) after treatment.

On average, people received their first kidney scan after diagnosis at age 44. This means that people were having their kidneys monitored very soon after diagnosis. Just under 9 in 10 people get regular kidney scans.


There is a huge delay between onset of symptoms and diagnosis. The reasons for this are yet to be uncovered. However, it is clear that more work needs to be done to raise awareness of BHD. Given the first symptoms commonly appear on the skin or in the lung, raising awareness of these symptoms among the general public as well as skin and lung doctors could help reduce the diagnostic delay.

More work also needs to be done to find better treatments, particularly for the skin. We are funding research to better understand fibrofolliculomas so we can identify potential therapies. In the future, we could use BIRT to help identify people to take part in clinical trials to test new treatments.

How Do I Get Involved?

We partnered with Pulse Infoframe to power the registry. Their platform is easy to use, and registration is easy.

1. Visit the BIRT website and fill out the registration form.
2. Check your email inbox and create a login to activate your account.
3. Sign the consent form.

After doing these 3 steps, you can start filling out the surveys.

We understand that there is quite a lot of information required, and it may take around an hour to complete the surveys. However, the BIRT platform is very flexible, and you do not have to do everything in one go. Your progress is tracked and is automatically saved so you can complete the surveys at your own pace. We are extremely grateful for your time and help in participating in the registry.

You can also help us by telling your family and healthcare professionals about BIRT. We have a letter you can use to tell your family members, and there is a leaflet advertising the registry to doctors.

If you have any questions or would like more information, please email us.

Let’s Raise Awareness of BHD Together

Early diagnosis of Birt-Hogg-Dubé syndrome (BHD) is vital so people can be monitored for kidney cancer. However, many doctors have never heard of the condition, so it often takes people years to be correctly diagnosed. At the BHD Foundation we work alongside the community to raise awareness of this rare and important condition. 

Social Media

Social media is an effective way to increase visibility of BHD, often reaching new and varied audiences. This year we have taken part in several awareness days and social media takeovers. In January we took over the Medics 4 Rare Disease (M4RD) Instagram page. M4RD is a charity which educates future doctors about rare diseases. 166 people viewed the BHD content. Only 1 in 8 of those who completed the poll following viewing had previously heard of BHD. This shows the potential to raise awareness among medical professionals.

This was followed by Rare Disease Day in February. On Rare Disease Day we published Lea’s BHD story ‘From Collapsed Lung to Ironman’ with digital health company Congenica. Her empowering story shows how important it is for rare conditions to be recognised and why on Rare Disease Day we need to come together and raise awareness.

Our most successful awareness day so far was World Pneumothorax Day on June 30th. This is a day that we spearheaded in 2021 to mark the launch of the NHS Familial Pneumothorax Rare Disease Collaborative Network. World Pneumothorax Day is now a worldwide event. This year several major charities got involved on social media including the European Lung Foundation and Lung and Asthma UK. Additionally, a member of the community Joanna shared her BHD story ‘Married on a mountain with a collapsed lung’ with us, which was published in Rare Revolution Magazine. It was one of their top blogs with 375 reads on the week it was published. That is 375 more people who will have heard of BHD. 

Leaflets and Conferences

We develop educational resources about BHD for doctors. This year we created a BHD awareness leaflet (a printable version is also available). This leaflet is designed for doctors who have never heard of BHD. It gives an overview of the symptoms and recommendations on what to do if BHD is suspected. This leaflet was shared on a virtual platform at the European Respiratory Society Congress and WONCA, the general practitioner conference. We hope to take it to many more events in the future including in-person conferences. Our focus will be lung, kidney and skin conferences.  However, we will also target other doctors who may see the symptoms of BHD. This includes radiologists, emergency medicine doctors and general practitioners.  

We also have patient leaflets. They provide information on the symptoms of BHD and how to treat them. Although they are aimed at patients, they can also be a useful introduction to BHD for doctors.  You are welcome to print them out and take them to your doctor appointments.


Earlier this year we were interviewed for a Rare Disease Podcast called ‘Wait How to Do You Spell that?’ with Patient Worthy. In the podcast we discussed BIRT, the new BHD patient registry, and the work of the BHD Foundation.

Talking about BHD on different platforms allows us to reach a wider audience and further educate people about BHD.

How can you get involved in raising awareness?

We publish personal stories about BHD on our website. It can be a really impactful way to raise awareness. We’ve also had feedback from the community about the importance of hearing from others about their lived experiences of BHD. 

If you would like to share your BHD story please email us or message us on FB. This can be in the form of a written or video interview or a short film.

You can also raise awareness by:

  • Directing your doctors to our webpage or giving them one of our leaflets
  • Taking part in awareness days.
  • Sharing our social media posts.
  • Fundraising for BHD. Visit our ‘Get Involved’ page to find out more about our new fundraising campaign.

Thank you to everyone who has helped us to raise awareness of BHD. By raising awareness more people will be diagnosed, more funding will be available for research and we will move closer to new therapies and eventually a cure. Let’s work towards a future with increased awareness of BHD together.

If you have any ideas on how to raise awareness we’d love to hear from you. Email us at

Fundraise for the BHD Foundation!

The BHD Foundation is thrilled to launch our new fundraising campaign. We are raising funds to develop a new BHD Foundation website to better support the BHD community.  Our current website was created some time ago and is in desperate need of updating. The new website will be optimised for use on mobile phones and tablets and will better meet the needs of patients and families. We are working with our Patient Advisory Board who will be involved in content development, design and user testing throughout.

Prize Draw

We are delighted to announce the launch of the BHD Foundation Website Prize Draw which opened to members of the BHD Community on 07 October 2022 and will remain open until 30 November 2022.

We are so grateful to have received several kind donations from various companies and individuals. Our star prize is a week’s accommodation in a luxury cottage in the Cotswolds, UK!! Other amazing prizes include artwork, home furnishings, power tools and gift vouchers.

The Prize Draw is free to enter however there is a suggested donation of £5.00 or equivalent in your country’s currency per ticket.  All donations will be gratefully received and used solely for the development of the new BHD Foundation Website. To enter the draw and view the Terms and Conditions please click here.

Fundraise on Facebook

We are also pleased to announce that the foundation has signed up to receive donations through Facebook. This means that you can now help the foundation raise funds by asking for donations to be made for your birthday, or you can run your own fundraising campaign. Click here to start your campaign.

Create your Own Fundraising Event

Are you an avid walker, lover of baking or always wondered what it would be like to trim those lovely locks off in the name of a good cause? Then we would love you to get involved with supporting the BHD Foundation. Fundraising is a great way to not only support us, but also to have some fun and push yourself out of your normal boundaries. Have a look at our fundraising ideas for more inspiration. Let us know if you plan a fundraising event and we will support and promote you in as many ways as we can.

We also have several other ways you can fundraise or donate to us. For more information and fundraising ideas visit our new Get Involved page on the BHD Foundation website.

We will also be discussing our new fundraising campaign at the BHD Community Symposium taking place on Saturday 8th October. There’s still time to sign up and get your free ticket for the event to hear the latest research, meet BHD experts and more. Want to attend but can’t make the event live? Register for your ticket now and we will send you a recording of the event to watch in your own time!

As a charity we rely solely on donations made by members of the public and organisations. We really appreciate the support from the BHD community and look forward to hearing all your fantastic fundraising ideas.

2022 BHD Community Symposium

We are looking forward to welcoming you to the 2022 BHD Community Symposium. The event takes place online on Saturday 8th October. Everyone is welcome including people with BHD, friends, family members, doctors and researchers.

We have a very exciting lineup this year with experts from across the world sharing their research.  We have been working with speakers to ensure the talks are pitched at a level which is accessible to everyone. There will also be plenty of opportunities to ask questions and we want you to get involved!

Join us at our research sessions and:

  • Discover more about the genetics of BHD and what we can learn from registries.  
  • Explore why certain people get certain BHD features and others do not.
  • Hear about why lung cysts may develop and how lung collapses may occur.
  • Learn about what happens in BHD kidney cancer and new treatments that are being investigated.
  • See how together we can make our voices heard and raise vital awareness of BHD.

We will also be hosting Meet the Expert sessions where you talk with BHD experts about BHD. Send your questions in advance or ask them on the day.

View our full programme to find out more about the day.

Tickets are available at:

A recording will be available to all registered attendees after the event. Therefore, if you are unable to make it but are interested in any of the sessions we recommend registering.

Please contact with any questions at

We look forward to seeing you on Saturday 8th October.

Full programme

RAREfest22: Unique Festival puts Rare Diseases into the Spotlight! 

The BHD Foundation is excited to attend RAREfest22 in November this year. We are also proud to announce we are media partners for this important event in the rare disease calendar!

Did you know that 3.5 million people in the UK are living with rare conditions? That’s around about the population of Wales. Hang on, didn’t we say RARE?! Well, with over 10,000 different rare conditions, what may be individually rare becomes collectively common. In fact, 1 in 17 of us may be affected in our lifetime so it’s something we should all be curious about. With this in mind, CamRARE is making it their priority to push rare diseases into the spotlight.

RAREfest22 is a rare disease-inspired, unique festival that will spark curiosity and challenge perceptions. It will showcase science and innovative tech while giving a voice to those living with rare conditions and their families. Taking place on November 25th and 26th, this is a FREE event for the experts and the curious of all ages. It promises a feast of expert speakers, immersive exhibits, films and art. It is a great opportunity to mix and mingle with the rare disease community. Scientists, medical professionals, companies developing tech and treatments will also be attending.

RAREfest22 highlights include:

Singing Science – Genomics The Musical –

A one-person show combining the basics of Genetics and the impacts on the rare disease community. The show provides an engaging way to familiarise yourself with key concepts – fit for all ages.

Illumina – The Cambridge DNA Journey –

A visual map and timeline of the journey from the discovery of DNA to the development and application of genetics and genomics to diagnostics and healthcare in Cambridge.

Rare Youth Revolution –

Join the RARE Youth Revolution for an immersive experience into the life of young people living with rare diseases and some invisible symptoms they experience. Talk to the team about internship opportunities for young people living with rare diseases.

Are you a person or family affected or perhaps you have a neighbour or friend who is? Maybe you’re curious about the world and love to share that with your kids? Are you a researcher based in a lab, a healthcare worker in a busy hospital? Perhaps you’re a teacher with a class full of inquisitive kids, or a student embarking on their next adventure? Whomever you are we guarantee this will be a fascinating day out and you’ll learn something new that will blow your mind. So come along, bring your friends and family and make a day of it! For the experts. For the curious. For all ages. For the whole family. For everyone. For FREE.

For more information visit the festival website. Tickets are free and available at

The BHD Foundation aims to support, inform and connect the BHD community worldwide. We foster the relationship between patients, clinicians and researchers to build a strong and versatile community. We look forward to attending RAREfest22 and growing our network across the rare disease space.

Explaining the Different Types of Kidney Cancer

Kidney cancer is the most serious complication of Birt-Hogg-Dubé syndrome (BHD). There are many different types of kidney cancer. In this toolkit, we explain the different types of kidney cancer and find out if they’ve been reported in BHD.

Kidney Cancer Symptoms

There are often very few symptoms of early-stage kidney cancer. Symptoms are often similar regardless of which type of kidney cancer you have. When symptoms do occur, they include blood in your urine, a lump or swelling in your side and pain in the side or back below the ribs. If you have any of these symptoms (or other kidney cancer symptoms), please see your doctor.

How Do I Know What Type of Kidney Cancer I Have?

Although you may have different scans during your diagnosis, it is not often possible to tell which type of kidney cancer you have from these. Instead, the scans tell the doctors about the size of the tumours and where in the kidney they are located. These scans can also often show if the cancer has spread to other parts of the body. A small sample of the tumour (known as a biopsy) may be taken to confirm the type of kidney cancer. A pathologist will study the sample under a microscope and look for cellular features associated with the different types.

Knowing which type of kidney cancer you have may impact the treatment you receive. Some kidney cancer types grow faster and are more likely to spread than others. However, in some cases you may only find out what type of kidney cancer you have after treatment. Your doctor will always discuss this with you to ensure you receive the best treatment available. Generally, outcomes are good and kidney cancer can be treated successfully. However, the quicker kidney cancer can be identified, the easier it is to be treated.

Kidney Cancer Types

Below we outline some of the types of kidney cancer. Please note this list is not exhaustive and there are other rare kidney cancer types not on this list.

Clear Cell Renal Cell Carcinoma (ccRCC)
This is the most common type of kidney cancer in the general population. The name ‘clear cell’ refers to how the cells look when they are viewed under a microscope. People with VHL tend to get ccRCC.

How does it behave?
ccRCC can be fast or slow growing. If not treated, ccRCC can spread to other parts of the body.

How is it treated?
If found quickly, ccRCC normally responds well to treatment. Treatment depends on several factors including the stage of kidney cancer you have. If possible, surgery is the preferred option. However, you may have types of treatment including immunotherapy and targeted therapies. Sometimes, ablation or radiation may be used. This often occurs when a person cannot have surgery. This can happen if the tumour is close to blood vessels or removing it by surgery will impact kidney function.

Has it been reported in BHD?
Yes, although not common, ccRCC has been reported in people with BHD.

Papillary RCC
This is a type of non-clear cell RCC. The term ‘papillary’ refers to the shape of the tumour. Finger-like projections can be found in most of the tumours. There are two types of papillary RCC. Type 1 is more common than type 2 which is often associated with HLRCC

How does it behave?
Type 1 grows more slowly than type 2 which is faster growing and more aggressive. If left untreated, papillary RCC may spread.

How is it treated?
The most common treatment strategies for papillary RCC are surgery and radiation therapy. In some cases, where the cancer has spread and surgery is not possible, you may have chemotherapy.

Has it been reported in BHD?
Yes, although not common, papillary RCC has been reported in people with BHD.

Chromophobe RCC
This is a type of non-clear cell RCC. It is the most common type of RCC after ccRCC and papillary RCC in the general population. Under a microscope, the cells appear much larger than other types of kidney cancer cells.

How does it behave?
Chromophobe RCC tends to be slow growing and less aggressive. Although it can still spread to other parts of the body, this is less likely than in ccRCC and papillary RCC.

How is it treated?
If the cancer remains localised (i.e. it has not spread), surgery is the preferred option if available. In BHD, surgery is normally performed when the largest tumour reaches 3 cm.  If the cancer has spread, a combination of systemic anti-cancer therapy (treating the whole body) and a type of surgery called cytoreductive surgery may be performed. Common anti-cancer drugs used are sunitinib or everolimus. The aim of cytoreductive surgery is to remove as many cancer cells within the kidney as possible.

Has it been reported in BHD?
Yes, chromophobe RCC is one of the more common types of kidney cancer found in people with BHD.  

An oncocytoma is a type of tumour that is not cancerous (benign). They are unlikely to become cancerous but there have been reports of this happening in the literature. However, it is not possible to tell if a tumour is cancerous from an imaging scan alone.

How does it behave?
Oncocytomas are slow growing. They are often monitored by regular imaging scans to check their growth over time.

How is it treated?
If they reach a certain size, oncocytomas are normally removed by surgery. In BHD, surgery is normally performed when the largest tumour reaches 3 cm.  

Has it been reported in BHD?
Yes, oncocytomas are one of the more common types of kidney tumour found in people with BHD.

An angiomyolipoma is a type of tumour that is not cancerous (benign). These are tumours that that contain muscle, fat and blood vessels. They are often serious due to the risk of the tumours bursting and bleeding. Unlike many of the tumour types on this list, angiomyolipomas can be clearly seen on ultrasound scans. They are common in people with TSC.

How does it behave?
Angiomyolipomas grow very slowly. Their growth is often monitored regularly by imaging scans. The risk of the tumour bursting and bleeding increases with size.

How is it treated?
If an angiomyolipoma grows larger than 4 cm, treatment may be recommended. You may have surgery, ablation therapy or a procedure called an arterial embolization. This reduces blood flow to the tumour and causes the tumour to shrink. If you have TSC, the preferred treatment is everolimus.

Has it been reported in BHD?
Yes, angiomyolipomas have been reported in people with BHD.

Hybrid Oncocytic/Chromophobe Tumour (HOCT)
HOCT is a type of kidney cancer made up of cells from oncocytomas and chromophobe RCC. It is mainly found in people with BHD although sporadic cases have been reported.

How does it behave?
HOCT is slow growing and is unlikely to spread. There have been rare cases of HOCT spread reported. The growth of HOCT is normally monitored by regular scans.

How is it treated?
HOCT is normally treated by surgery. In BHD, surgery is normally performed when the largest tumour reaches 3 cm.

Has it been reported in BHD?
Yes, this is thought to be the most frequent type of kidney cancer in people with BHD.

Other rare types of kidney cancer include collecting duct RCC, medullary RCC and MiT Family Translocation RCC. To date, none of these cancers have been reported in people with BHD. Some kidney cancers cannot be classified into any of these groups. Unclassified kidney cancers have been reported in people with BHD.

Despite the number of studies and case reports on BHD and kidney cancer, there are still many unknowns. These include how many people with BHD develop kidney cancer and a comprehensive study of the types of kidney cancer found. The BHD Syndrome International Registry (BIRT) aims to answer these questions. We need as many people as possible to join the registry so we can help researchers answer these important questions. Understanding more about BHD and kidney cancer will help guide treatment, from surveillance guidelines through to the development of new treatments or a cure. Join the registry now.

The International Kidney Cancer Coalition is a network of patient organisations that support people with kidney cancer. Find support near you.

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Monitoring and Treating Inherited Kidney Cancer

Recently several papers have been published about kidney cancer that are relevant to Birt-Hogg-Dubé syndrome (BHD). In this blog, we summarise the papers and share what we can learn from them.

Is surgery or active surveillance better?

There are many different types of kidney cancer. The most common types seen in BHD are chromophobe, oncocytoma or a mixture of the two. These cancers are often slow growing, and they rarely spread. A recent paper described a case of oncocytoma and discussed whether it should be managed with active surveillance (regular scans to monitor tumour growth) or surgery.

The case described a 66-year-old man who was admitted to hospital with back pain. A CT scan showed he had tumours on both kidneys. The biggest was 3.3 cm. Due to its large size, they were concerned it may spread to other parts of the body. This is because larger tumours are more at risk of spreading.  Therefore, he had a partial nephrectomy (a type of kidney surgery) to have it removed. Samples of the tumour were then analysed, which revealed a slow-growing oncocytoma. At this point, as the cancer was shown to be an oncocytoma, the patient was given options for the smaller tumours. Either he could have them removed or have active surveillance. He opted for the surgery.

The researchers reviewing this case agreed that surgery was the best treatment option for the large tumour. However, they suggest that active surveillance may be the best option for smaller oncocytomas. This is because tumours under 3 cm are very unlikely to spread so the benefit of surgically removing them does not outweigh potential complications caused by surgery.  

Although this paper is not about BHD it does comment on a type of kidney cancer seen in BHD. It explains that oncocytomas are very unlikely to spread and that active monitoring is often the best option. This is in line with current BHD recommendations that suggest active kidney surveillance until tumours research 3 cm and then surgery.

Is active surveillance cost-effective?

The next study explored whether active surveillance of the kidneys, in conditions that predispose to kidney cancer, is cost-effective. They focused on a condition called HLRCC. Like BHD, HLRCC can cause kidney cancer. However, in HLRCC the tumours tend to grow more quickly and appear in younger people. The team assessed the cost-effectiveness of doing a yearly MRI scan in HLRCC compared with doing no MRI scans. They looked at a range of different age groups from 11 to 60. To determine if the scans were cost-effective, they assessed the effect of the scans on quality and length of life in addition to the monetary cost. They found that active surveillance was cost-effective across all age groups. Although this paper did not look at BHD, BHD does share similarities to HLRCC. Therefore, it suggests that active surveillance in people with BHD may not only positively impact their lives but be cost-effective. Before a study can be done looking at the cost-effectiveness of active surveillance in BHD, further research is needed to determine how often people with BHD should be screened.

Are there alternatives to surgery?

Lastly, we looked at a review of another type of kidney cancer called renal angiomyolipoma (rAML). rAML is a rare type of kidney cancer that is sometimes seen in BHD. Similar to the other types of cancer seen in BHD it is normally slow growing and active surveillance is recommended. Once it reaches a certain size it is then often removed by surgery.

rAML is also seen in tuberous sclerosis complex (TSC). TSC is a rare genetic condition that shares many similarities to BHD (read our recent blog post where we discuss what TSC can teach us about BHD). In addition to active surveillance, people with TSC-associated rAML can be offered a drug called an mTOR inhibitor. mTOR signalling is involved in cell growth and survival and is often overactive in cancer. mTOR inhibitors block this activity and are used to treat cancers. They are used in TSC-associated rAML to reduce the size of tumours and delay the need for surgery. Research into mTOR signalling and BHD is still ongoing so the benefit of mTOR inhibitors in BHD is unknown. However, this paper demonstrates that treatments are being developed for rare cancer types and that further research into BHD may one day find an alternative treatment to surgery.

The one stark similarity between all these papers is how there are no clear guidelines on when slow-growing kidney cancers, such as those seen in BHD, should be removed. Current research into BHD suggests it should be when they reach 3 cm. At the BHD Foundation, we want a clear answer to this question. We have launched the BHD syndrome International Registry (BIRT) to help us collect as much information about BHD as possible and drive forward research. Take part in the registry now.

Should People Who Have a Collapsed Lung be Tested for BHD?

Birt-Hogg-Dubé syndrome (BHD) is an inherited condition associated with mutations in the gene folliculin (FLCN). It is characterised by skin lesions called fibrofolliculomas, lung cysts, collapsed lungs and an increased risk of kidney cancer. As different people may have different symptoms, the diagnosis of BHD may be missed. It is therefore thought that BHD is underdiagnosed. Early diagnosis of BHD is important to identify and treat any kidney cancer as early as possible. Finding effective ways to diagnose BHD could help reduce any future burden of kidney cancer.

A new study has been published looking at the prevalence of BHD among people who have a collapsed lung for no apparent reason (e.g. not as a result of a direct injury). This is called a primary spontaneous pneumothorax (PSP). Currently, a CT scan is not routinely performed on people who have a PSP. However, it is thought that at least 8 in 10 people with BHD have lung cysts. These lung cysts have features that are unique to BHD. For example, they are typically found at the base of the lungs and have an irregular shape. Therefore, CT scans may be useful in diagnosing BHD. The authors also discussed whether CT scans should be performed on everyone who experiences a PSP to aid the diagnosis of BHD.

A questionnaire was sent to 475 people who had a PSP between 2004 and 2017 at the Rijnstate Hospital in Arnhem, the Netherlands. 178 people completed and returned the questionnaire. Of these, 88 were included in the study for genetic testing. 3 people were found to have a mutation in FLCN. 2 of these people were related and had multiple family members with a history of collapsed lungs. The other person had a family history of kidney cancer. All 3 people had fibrofolliculomas. One person was found to have kidney cancer. This was successfully treated with surgery.

A chest CT scan was available for 83 out of 88 people. Cysts were found in 14 people, of whom 6 had multiple cysts. All 3 people with BHD had multiple lung cysts. Most of these were found in the base of the lungs, typical of BHD.

In retrospect, all 3 people who were diagnosed with BHD in this study had features that could have allowed them to be diagnosed earlier. This highlights the importance of raising awareness of BHD among doctors who would see someone with a PSP including lung doctors, radiologists and emergency doctors. For this purpose, the BHD Foundation has created a BHD awareness leaflet.

Based on this study and other previous studies done, the authors recommend that a CT scan should be performed for everyone who presents with a PSP. They also suggest that if lung cysts are present, genetic testing for BHD should be done. A lung collapse is often an early symptom of BHD and so this would hopefully result in an earlier diagnosis of BHD. It would also allow their family members to be tested. Additionally, performing a CT scan in everyone that has a PSP could allow the diagnosis of other cystic lung diseases such as LAM.

In the future, we would like to see more studies like this being done on larger groups of people. The more people involved in research in BHD, the more confidence you can have in the data. Better quality data will help us better inform guidelines on the diagnosis and management of BHD. We launched the BHD syndrome International Registry (BIRT) to help us collect as much information about BHD as possible and drive forward research. Take part in the registry now.