Case report: soft tissue metastasis from immature teratoma of the testis: second case report and review of the literature.

BACKGROUND: Testicular cancer, like other histopathologic types, commonly metastasizes to the lungs, liver, and brain. Spread to soft tissue, however, is rare with only four cases with seminoma reported. However, one case with metastasis of testicular immature teratoma to soft tissue was documented previously. CASE DESCRIPTION: We report the case of a 38-year-old man with recurrent immature teratoma of the testis who presented with a painless soft tissue mass in the left thigh previously treated with standard chemotherapy. After removal of the soft tissue mass, his serum alpha-fetoprotein level had returned to the normal range. LITERATURE REVIEW: To our knowledge, this is the second case of immature teratoma of the testis metastasized to soft tissue. PURPOSES AND CLINICAL RELEVANCE: We suggest that for a man with testicular cancer who has a soft tissue mass, metastasis of soft tissue from testicular cancer and other solid malignancies should be considered in the differential diagnosis of a soft tissue mass together with primary soft tissue sarcoma.