Birt-Hogg-Dubé syndrome: awareness is important!

Abstract

Birt-Hogg-Dubé (BHD) is a rare syndrome of inherited renal cell carcinomas, characterised by cutaneous lesions and pulmonary cysts and pneumothorax in a vast majority of the patients. Awareness of this syndrome is important in order to refer patients for genetic counselling and personalised follow-up as soon as possible. We describe a case of a 30-year-old female referred to our institution due to incidental discovery of solid bilateral renal masses. Renal biopsies were consistent with chromophobe tumour, and bilateral nephrectomy was performed. Gross examination revealed deformed kidneys with 28 brown and solid lesions, size variable between 0.1 and 6 cm, histologically corresponding to renal cell carcinomas, chromophobe type. Genetic test was required that showed a c.573delGAinsT frameshift mutation in heterozigosity at the folliculin gene, consistent with BHD diagnosis.

Development of Bilateral Renal Cell Carcinoma in the Birt-Hogg-Dubé Syndrome Before and After Living-Related Kidney Transplantation

“…7 In 2002, it was reported that the syndrome is caused by a mutation in the FLCN gene (a tumor suppressor gene located on the short arm of chromosome 17). 8 The clinical picture of BHD syndrome is variable, with cutaneous lesions, pulmonary cysts, and pneumothorax observed in up to 90%-92%, 90%, and 24%-38% of the cases, respectively. 8 Approximately 30% of the patients with BHD syndrome develop renal tumors, which are typically bilateral and multifocal and appear simultaneously or metachronously.…”

“…8 The clinical picture of BHD syndrome is variable, with cutaneous lesions, pulmonary cysts, and pneumothorax observed in up to 90%-92%, 90%, and 24%-38% of the cases, respectively. 8 Approximately 30% of the patients with BHD syndrome develop renal tumors, which are typically bilateral and multifocal and appear simultaneously or metachronously. The median age at tumor diagnosis is 46 to 50 y.…”

“…Clear cell and papillary tumors have been described; however, they make up for <10% of BHD renal tumors. 4,8,9 The odds ratios for renal tumors in BHD syndrome-affected family members were reported to be 6.9 (95% confidence interval, 1.5-31.6) after adjusting for age and approximately 9.0 after considering other risk factors (sex, smoking status, hypertension, and body mass index). 10 Once the diagnosis of the BHD syndrome is established, serial baseline chest and abdominal imaging should be performed.…”

“… 7 In 2002, it was reported that the syndrome is caused by a mutation in the FLCN gene (a tumor suppressor gene located on the short arm of chromosome 17). 8 …”

“…The clinical picture of BHD syndrome is variable, with cutaneous lesions, pulmonary cysts, and pneumothorax observed in up to 90%–92%, 90%, and 24%–38% of the cases, respectively. 8 …”