Testicular Seminoma Metastasis to the Gastrointestinal Tract and the Necessity of Surgery

Germ cell tumors rarely metastasize to the gastrointestinal (GI) tract with an incidence that is less than 5%. Germ cell tumors can be divided into two groups: pure seminomas and non-seminomas. Pure seminomas are characterized by their profound response to chemoradiation. Within the group of germ cell tumors, pure seminomas are least likely to metastasize to the GI tract with an incidence of less than 1%. The most frequent mode of metastasis to the GI tract is direct extension from the retroperitoneal lymph nodes, which drain the testes. Ileal and jejunal metastasis are more common due to their retroperitoneal locations as well as the fact that the testes have retroperitoneal lymphatic drainage. Due to the concern of retroperitoneal metastasis in germ cell tumors, retroperitoneal lymph node biopsies are advocated for accurate staging and diagnosis due to the possibility of occult involvement in these sites. Thus, amongst the GI sites for metastasis, the duodenum is the most uncommon location. The most common manifestations of GI metastasis are intestinal obstructions via volvulus or intussusception and not acute gastrointestinal bleeding. We present a case of chemoresistant pure testicular seminoma with metastasis to the duodenum with a complication of a massive upper GI bleed requiring emergent surgery.

Chemotherapy has a 90% success rate in patients with pure seminomas, even in the setting of disseminated disease. However, pure seminomas with GI metastasis have a lower response rate (60%) to chemotherapy. While there are documented cases of pure seminomas presenting with duodenal bowel perforation, or jejunal occult bleeding, this, to our knowledge, is the first case of duodenal metastasis causing massive acute upper GI bleeding. Amongst the prognostic factors for seminomas, GI metastasis is listed as a poor prognostic factor with respect to chemotherapy. Given the poor response rate with chemotherapy in GI metastasis of seminomas, early surgical management should be considered in cases where GI metastasis occurs. A retroperitoneal lymph node biopsy should be highly considered in patients with a history of seminoma in the staging process, as occult lymph node involvement can lead to future gastrointestinal metastasis that is associated with a poorer prognosis.