Breast cancer in a patient with Birt-Hogg-Dubé syndrome (BHDS) with dramatic response to neoadjuvant chemotherapy.

This is a case of 49-year-old white woman who presented with a rapidly growing right sided breast mass. A subsequent punch biopsy confirmed grade 3 invasive mammary carcinoma of no special type which was negative for oestrogen receptor, progesterone receptor and Her-2 neu overexpression. She was a carrier of folliculin gene mutation that is characteristic of Birt-Hogg-Dubé syndrome (BHDS), a condition known to cause skin lesions, renal cancers and pneumothoraces. Family history revealed patient's mother, grandmother and maternal aunt developed renal cell carcinomas during their lifetime and were positive for the same germ line mutation. Tumour tissue was positive for TP53 mutation and negative for BRCA1, BRCA2 and other genes commonly associated with breast cancer. We report a patient with BHDS presenting with breast cancer that showed dramatic response to neoadjuvant chemotherapy prior to bilateral mastectomy, local chest wall radiation and 6 months of adjuvant capecitabine. © BMJ Publishing Group Limited 2020. No commercial re-use. See rights and permissions. Published by BMJ.