Recently, three new interesting BHD case studies were published:

Dodds et al. (2016) report a case of colorectal carcinoma in a patient with BHD syndrome that had a distinct oncocytic component. DNA analysis was previously performed on the patient and he was found to have an exon 12 frameshift FLCN mutation. The association of BHD syndrome with colorectal neoplasia is controversial and colorectal screening is not usually part of the BHD guidelines. However, the presence of oncocytes in this case is interesting given the oncocytic nature of renal tumours commonly seen in BHD patients and raises the possibility that the syndrome may have contributed to colorectal neoplasia. Therefore, the group proposes that identifying prominent oncocytic change in colorectal carcinoma may warrant further investigation to identify unsuspected cases of BHD syndrome.

Cesar et al. (2016) report a case of a 28-year-old man in Portugal presenting a 1-year history of skin lesions on the nose that show features compatible with a fibrofolliculoma. The patient had in his past medical history 2 spontaneous pneumothoraxes, in addition, his mother underwent right nephrectomy for a renal tumour at the age of 38. Genetic analysis revealed a heterozygous mutation in exon 4 of the FLCN gene, both in the patient and in his mother.  Small cysts were observed in the basal regions of both lungs. In addition to identification of this novel mutation, this BHD case is of particular interest because of the pedunculated clinical appearance of the fibrofolliculoma, underlining the importance of considering BHD syndrome in the differential diagnosis of facial papules, even if of atypical morphology.

Martins et al. (2016) present a case of a non-smoking, 57-year-old male with a 3-week history of dyspnea and dry cough in Portugal. The patient had in his past medical history a spontaneous pneumothorax 20 years ago. Chest X-ray showed a new pneumothorax with complete lung collapse and chest-CT showed multiple pulmonary cysts. In addition, patient was noted to have skin lesions over his face, neck and upper trunk, for at least 20 years. There was also a family history of similar skin lesions affecting his mother. The presence of these skin lesions together with recurrent pneumothorax was suggestive of BHD syndrome.  Genetic analysis confirmed the diagnosis revealing a previously described heterozygous mutation in exon 6 of the FCLN gene. This is the second reported case of BHDS in Portugal. The group aims to raise awareness of BHDS in order to allow for early detection and prevention of more serious complications, such as renal cancer, both in patients and in relatives at-risk.