Concurrent Birt-Hogg-Dubé Syndrome and Hereditary Paraganglioma-Pheochromocytoma Syndrome Presenting as Metastatic Renal Cell Carcinoma in a 25-Year-Old Man: A Case Report.

INTRODUCTION: Birt-Hogg-Dubé syndrome and hereditary paraganglioma-pheochromocytoma syndrome are rare genetic cancer syndromes that predispose patients to renal neoplasia. We report a case of a 25-year-old man with both Birt-Hogg-Dubé syndrome and hereditary paraganglioma-pheochromocytoma syndrome who presented with painless gross hematuria and was found to have metastatic clear cell renal carcinoma. CASE
PRESENTATION: A previously healthy, 25-year-old man presented to his outpatient primary care physician with painless gross hematuria. Urinalysis results demonstrated hemoglobinuria, and serum chemistry results demonstrated a creatinine level of 1.61 mg/dL (baseline of 0.96 mg/dL). A computed tomography scan showed that the patient had a left renal mass, renal vein thrombosis with inferior vena cava extension, and nodal and hepatic metastasis. Biopsy specimens of the left renal mass and liver demonstrated clear cell carcinoma. The patient underwent cytoreductive nephrectomy, caval thrombectomy, and partial colectomy with reanastomosis. He received palliative therapy with 1 mg/kg of ipilimumab and 3 mg/kg of nivolumab for 4 cycles.
CONCLUSION: To our knowledge, this is the first known case report to date documenting a patient with concurrent Birt-Hogg-Dubé syndrome and hereditary paraganglioma-pheochromocytoma syndrome. This case demonstrates the exceptionally young presentation of metastatic renal cell carcinoma with this genotype.