A 26-year-old Caucasian male presented to the joint infertility outpatients clinic with primary infertility. His medical history included hypertrophic cardiomyopathy (HCM) due to genetically confirmed MYH7 sarcomere protein mutation, treated with implantable cardioverter-defibrillator while his partner was a healthy 24-year-old Caucasian nulliparous female. Initial investigations showed hypertestosteronemia (Testosterone: >51.0 nmol/l) and azoospermia, hence the couple was referred for endocrine review. During consultation, he reported hoarseness of voice, hypersexuality, and increased hair distribution over the past 3 years. He denied ever having used anabolic steroids and was only on amiodarone to ameliorate arrhythmias from his known HCM.
On examination he was hirsute with bilaterally small testes. A testicular/scrotal ultrasonography was unremarkable. Subsequent investigations revealed elevated testosterone (52.9 nmol/l), b-hCG (900 IU/l) and suppressed FSH and LH: <1 IU/l. The provisional diagnosis of an extragonadal germ cell tumor (EGCT) was made and whole body contrast enhanced CT revealed a 7×6×5 cm mass of the anterior mediastinum without further disease dissemination.
Due to his HCM and reduced EF: ~35% he was not eligible for neo-adjuvant treatment with bleomycin-etoposide-cisplatin (BEP), in view of the increased risk for cardiotoxicity. He was instead referred for transthoracic resection of the tumor, which he had uneventfully with R0 resection margins. Immediately following excision of the mediastinal mass, his testosterone substantially dropped (Testo: 1.0 noml/l) confirming that the mediastinal mass was the source of β-hCG driven testosterone hypersecretion. Histopathology revealed a mixed primarily seminomatous (95%) with minor teratomatous (5%) component EGCT.