Histological conversion of seminoma of testis to metastatic choriocarcinoma in left cervical lymph node: An unusual phenomenon

Abstract

Germ cell tumors (GCT) of more than one histological subtype (although very rare) can be present in the same patient. We present a 29-year-old male who presented with a cervical lymph node swelling. The tissue received was a globular mass with a thick cystic wall and necrotic areas. A histopathological examination revealed the presence of residual lymphoid tissue in the form of lymphoid follicles, areas of hemorrhage and necrosis, tumor nests, and perivascular distribution of tumor cells. The neoplastic cells were arranged in a vague glandular pattern and also showed squamoid-like morphology on the basis of which a diagnosis of metastatic adenosquamous carcinoma was made. The patient was subjected to a whole-body positron emission tomography (PET) scan to look for primary on which a testicular mass was discovered; seminoma on histology. The sections of the cervical mass were revisited and trophoblastic cells were identified; they were also positive for β- human chorionic gonadotropin (hCG) on Immunohistochemistry. Therefore, a diagnosis of metastatic choriocarcinoma from seminoma testis was made. The direct derivative of germ cell neoplasia in situ/intratubular germ cell neoplasia being seminoma; it has the capacity for histological conversion to more differentiated forms (choriocarcinoma in this case).