Testicular Embryonal Carcinoma With Retroperitoneal Metastasis and Normal AFP and HCG: A Case Report

Testicular germ cell tumors are common malignant tumors in young men, among which embryonal carcinoma, as an important subtype of non-seminomatous germ cell tumors, is usually accompanied by elevated serum tumor markers. This case report describes a 24-year-old male patient with testicular embryonal carcinoma and retroperitoneal lymph node metastasis, yet with persistently normal serum markers, posing significant diagnostic challenges. Diagnosis was ultimately confirmed through imaging, histopathology, and immunohistochemical analysis. The patient underwent radical orchiectomy followed by standard bleomycin, etoposide, and cisplatin (BEP) chemotherapy and showed no recurrence at 12-month follow-up. This case highlights the necessity of a multidisciplinary diagnostic approach, integrating clinical evaluation, imaging, and immunohistochemistry, to ensure accurate diagnosis, particularly in marker-negative presentations. It also confirms the efficacy of established treatment protocols and emphasizes the importance of heightened clinical vigilance and long-term follow-up for such atypical cases.