September is Urology Awareness Month – a month to raise awareness of urological diseases including kidney cancer. This campaign takes place every year, to spread knowledge and bring together the urology community, such as researchers, doctors, allied healthcare professionals and patients.

How is kidney cancer relevant to BHD?

BHD is a genetic disease and, in some people, it can lead to tumours over time. Fewer than 1 in 3 people with BHD get kidney cancer. People with BHD may develop tumours in both kidneys or more than one tumour in the same kidney at the same time. However, in most cases, tumours in the kidney(s) develop slowly and with regular monitoring and treatment are usually not life-threatening.

What measures can I take as a BHD patient?

It is recommended by experts to have regular kidney scans from adulthood. Early diagnosis is vital as it can lead to early management and treatment.

What are the symptoms of kidney cancer?

In the majority of kidney cancer cases, the signs of kidney cancer show during the mid-to-late stages of the condition. That is why it is so important to have kidney scans in BHD as you may not have any symptoms in the early stages.  There are a range of symptoms, but the most common symptoms include:

• Blood in your urine
• Constant pain below the ribs
• A lump or swelling in your side

Other less common symptoms of kidney cancer are:

• Unexplained weight loss and/or loss of appetite
• Extreme tiredness
• High blood pressure
• Night sweats
• High temperature

If you do have any of these symptoms, it is important that you see a doctor.

What are the treatments for kidney cancer?

The treatments for kidney cancer vary case by case. It’s important to tell your kidney doctor that you have BHD and that over time you may develop more kidney tumours. This may affect the treatment you are offered.  In BHD tumours are usually only removed once they are 3cm long. Treatments include:

• Partial nephrectomy: This is a procedure which removes the cancer but leaves as much of the kidney as possible. This type of surgery is usually recommended in BHD cases.
• Radical nephrectomy: This is surgery where your entire kidney is removed. For some patients, this can include the removal of surrounding structures such as fat and lymph nodes.
• Radiofrequency ablation: Radio waves are used to kill cancer cells.
• Medicines: There are targeted cancer medicines that aim to stop the cancer from growing. These are normally used in cancer that has spread around the body.  
• Radiotherapy: Radiotherapy uses radiation to kill cancer cells. This is not often used in kidney cancer cases.

There are other treatments available for kidney cancer. Please click here to read more about treatments.

How can I take part in Urology Awareness Month?

You can help spread awareness of kidney cancer and other urological conditions on social media, or by simply talking to friends, family, and colleagues.

The Urology Foundation have a range of resources that you can use. This includes, posters, leaflets and more. Their website also has a guide on how to raise awareness on social media and fundraising ideas.

Please join us this month to raise awareness about kidney cancer and help people with BHD learn more about the condition.

BHD is a condition that exists worldwide, but its’ effects may differ nation to nation. A group of researchers in South Korea looked at people with BHD to determine the presenting characteristics of the disease and it revealed interesting results. In this blog, we discuss the study and why the findings are so important. 

Looking for BHD

This study invited 31 participants who live in South Korean, all of whom had lung cysts, but had not been tested for BHD. Through genetic testing, the researchers diagnosed 11 out of the 31 participants with BHD after the FLCN gene mutation was identified. The people in the non-BHD group who had lung cysts were generally older and it is likely they are a result of normal ageing, as lung cysts can be found in the general population.

What did BHD look like in these patients?

To get an understanding of how the condition looked like in the BHD group, common features were compared with the non-BHD group. Firstly, there was a higher incidence of lung collapses in the BHD group than in the non-BHD group. Interestingly, kidney tumours were not seen in the BHD group, but one person in the non-BHD group had a history of kidney tumours. Kidney tumours are one of the common features of BHD, but it is important to note that it does not appear in every BHD patient.

Another finding that may have been unexpected is the prevalence of lung cysts between both groups. The researchers completed CT scans (using x-rays to create images of the inside of the body) to look at lung cysts. More than half of the non-BHD group had more than 40 lung cysts present. In contrast, only two people with BHD had over 40 lung cysts. 

Skin bumps are also a common characteristic of BHD but in this study, no one with BHD had skin bumps. 

How does this compare to the rest of the world?

To conclude if BHD does look different in South Korea, the authors of this paper looked at previous studies. Global data suggests that patients with BHD usually present with typical skin bumps and kidney tumours. However, these two characteristics were not common in the BHD group from this study. For example, no patients in this study had skin bumps, but in Western countries it’s been reported to be among one of the most common BHD symptoms. The most common feature that BHD patients shared in this study was lung collapse. Out of the 11 patients with BHD, 10 individuals had experienced lung collapse. In western countries, lung collapses are thought to occur in around 1 in 4 people with BHD.  Consequently, the researchers concluded that lung collapses may be more common in South Korean patients with BHD, with other symptoms such as skin manifestations and kidney tumours being less common when compared to BHD patients of other nationalities.

One size does not fit all

So, does BHD look different in South Korea? It is possible that BHD may look different in various parts of the world. For example, a major diagnostic criteria for BHD is skin manifestations but, in this study, this symptom was less common in South Korean patients. Genetic differences do exist among ethnic groups, and this is something we may need to consider when screening for BHD. If the presentation of BHD differs in some parts of the world, it is possible that countries will need their own tailored diagnostic criteria for BHD to ensure the condition is not undiagnosed in patients. However, to truly determine this, more research is required looking at BHD in people of different nationalities. It is also important to note that this study had a relatively small sample population, and although its results are similar to other studies done in South Korea,more research is needed to reach a stronger conclusion.

To read the full paper, please click here. We have also looked at BHD in populations of other counties including China and Sweden. 

A recent study investigated the genes that may cause parathyroid cancer. In this study, the researchers found the same genetic variants associated with BHD in some patients with parathyroid cancer. This blog will discuss the results and shed some light on if there is a link between the two conditions.

What is parathyroid cancer?

Parathyroid cancer is a condition in which cancer cells form in the tissues of a parathyroid gland. It is a rare condition, but it recurs in at least 1 in every 2 people. This means for a large number of people, the condition may return after it has been treated. There is currently no approved systemic therapy for the condition. This is therapy that travels through the entire body instead of targeting one area. The high reoccurrence rate coupled with the lack of systemic therapy, supports the need to develop new effective treatments. 

Parathyroid cancer has not been reported in BHD. However, non-cancerous BHD tumours have been seen in people with BHD.

Hunting for genes

The researchers analysed the genes of 17 patients with ‘sporadic’ parathyroid cancer. This is cancer that occurs in people who do not have a family history of that cancer.

Germline folliculin (FLCN) sequencing was performed in the 17 patients with sporadic parathyroid cancer. Mutations in the FLCN gene are associated with BHD. Germline sequencing is a type of DNA testing that looks for inherited mutations. The researchers found germline FLCN variant in three patients. Two of these patients were diagnosed with BHD. Consequently, the study presented the first recorded cases of parathyroid cancer in people with BHD.

The researchers also found somatic FLCN variants in two patients. Somatic mutations are changes in the DNA which occur after conception. In other words, they are not inherited. The two patients with somatic FLCN variants did not have any symptoms of BHD.

The researchers then analysed parathyroid non-cancerous tumours in 74 patients to look for FLCN variants. In this study, FLCN variants were not found in the 74 patients.

Why are these results important?

This study provides new information on if there is a possible link between parathyroid cancer and BHD. Firstly, FLCN mutations were found in people with parathyroid cancer. However, we do not know if BHD causes parathyroid cancer especially as it has been reported in so few people. It is possible that they developed parathyroid cancer by chance. Interestingly, although previously reported, no FLCN mutations were seen in the 74 people with non-cancerous parathyroid tumours in this study. These results point towards a clear need for further research.

To increase our understanding of BHD, it is crucial that we get more data. Last year, we launched the BHD syndrome international registry (BIRT). BIRT is a patient-reported database where people with BHD can upload information about their condition. The data can drive research and help answer questions. Take part in the registry now. Click here to email us with any questions.

We are sorry but this paper is not freely available. If you have any questions please contact us at contact@bhsyndrome.org