{Reference Type}: Case Reports {Title}: Hyperthyroidism in non-seminomatous testicular germ cell tumors: two case reports and literature review. {Author}: Favero D;Oing C;Seidel C;Rescigno P;Catalano F;Cremante M;Rebuzzi SE;Gatto F;Rosti G;Ferone D;Fornarini G;Cocchiara F; {Journal}: Front Oncol {Volume}: 14 {Issue}: 0 {Year}: 2024 {Factor}: 5.738 {DOI}: 10.3389/fonc.2024.1338438 {Abstract}: UNASSIGNED: Human chorionic gonadotropin (hCG)-induced hyperthyroidism is a rare paraneoplastic syndrome observed in non-seminomatous testicular germ cell tumors, due to a cross-reaction between the β-subunit of hCG with the thyroid-stimulating hormone receptor. The precise prevalence of this paraneoplastic phenomenon is unclear as, in the majority of cases, hyperthyroidism remains subclinical.
UNASSIGNED: Here, we present two cases of advanced metastatic non-seminomatous testicular germ cell tumors where patients exhibited signs and symptoms of thyrotoxicosis at primary diagnosis due to excessive serum β-hCG elevation, with complete remission of symptomatology after the start of oncological treatments and no signs of relapse at the time of publication of this report. Additionally, we provide a comprehensive review of the existing literature concerning this uncommon occurrence.
UNASSIGNED: Despite being a rare event, the presence of hyperthyroidism or thyrotoxicosis without clear etiology in a young man should lead to consider less frequent causes such as testicular tumors. Even if patients typically have mild symptoms that resolve after chemotherapy, in rare cases, it can be a life-threatening condition that requires prompt recognition and specific intervention.