Sugimoto et al. describe the case of a 39 year old Japanese woman who presented in clinic with left-sided back pain. She had no remarkable medical or family history. Contrast CT showed multifocal bilateral renal tumours. Histological analysis showed the tumours to be chromophobe renal cell carcinomas and capsular angiomyolipomas. Chromophobe RCC is only found in 5% of cases of sporadic kidney cancer, but is commonly seen in BHD and TSC. The patient had no skin lesions or lung cysts, and direct sequencing and copy number analysis showed no mutation in the FLCN gene, ruling out BHD as a cause. Genetic testing was not done on the TSC1 or TSC2 genes, but the patient did not have any of the other symptoms of TSC, making it unlikely that she has this syndrome either. However, the fact that her tumours were multifocal and bilateral suggests that there is a unknown genetic cause to this patient’s kidney cancer.

Johannesma et al. describe the case of a former Olympic swimmer who presented in clinic with recurrent pneumothorax. The patient was a non-smoker with no family history of pneumothorax but he had a medical history of 6 pneumothoraces, 3 on each side. High resolution CT revealed the presence of numerous cysts, predominantly in the lower lobes of the lung. Histopathological analysis showed that cysts were lined with pneumocytes and the inner surfaces stained positive for TTF-1 expression, indicating that BHD-associated lung cysts are histologically distinct from non-specific blebs and bullae. Genetic testing confirmed a diagnosis of BHD.

To find out more, download the latest version of the database here.