Beyond the Usual Barriers-A Primary Testicular Seminoma Arising in an Undescended Testis Presenting as a Colon Mass: A Case Report.

Germ cell tumors (GCT) in men usually arise in the gonads, presenting as a testicular mass. GCT may rarely involve the gastrointestinal tract due to metastasis from the testicular tumor. GCT arising from an undescended testis and presenting primarily with gastrointestinal symptoms is extremely rare. We hereby present a primary testicular seminoma in a 51-year-old gentleman, presenting with gastrointestinal symptoms. Sigmoidoscopy showed a large ulcero-infiltrative growth (7 × 6 × 3 cm) in the cecum and proximal ascending colon. The growth was biopsied with a clinical suspicion of a primary colonic adenocarcinoma. The biopsy showed infiltration by a seminoma. A thorough clinicoradiological evaluation revealed right cryptorchidism in the patient. He later underwent right hemicolectomy which revealed an adherent remnant cryptorchid testis at ileocecal junction and colonic infiltration by seminoma. Though challenging to diagnose seminoma at an unusual site, accurate biopsy diagnosis can play a decisive role in planning the timely surgery and adjuvant chemotherapeutic options.