A 37-year-old male patient was admitted for oncological follow-up. He had undergone right orchiectomy via the scrotal pouch two years prior for the resection of a tumor mass; the histopathological diagnosis was a combination of germ cell tumor, teratoma components, and areas of malignant degeneration. At that time, he had venous vascular invasion with metastases in the abdominal lymph nodes and the lungs (Figures 1A and 1B). The lung metastases were noncalcified. He underwent palliative treatment with chemotherapy, which resulted in stabilization of the tumor. A recent CT showed masses and nodules in both lungs, predominating in the right base, containing foci of calcification (Figures 1C and 1D). Biopsy of a pulmonary nodule was compatible with a post-pubertal metastatic teratoma with adenocarcinomatous transformation. At presentation, the patient was stable and receiving a new chemotherapy regimen.

 






Malignant transformation of teratomas is rare, occurring in only 3-6% of testicular germ cell tumors. The most common types of malignant transformation include sarcoma, carcinoma, and primitive neuroectodermal tumor. Teratomas with malignant transformation are usually metastatic at presentation, have a high recurrence rate, and are more aggressive than are teratomas without malignant transformation. The most common sites of metastasis are the lymph nodes, liver, and lungs. The treatment of teratomas with malignant transformation remains challenging. The standard treatment is radical orchiectomy, with or without chemotherapy and/or radiotherapy.(1,2)



REFERENCES



1. Ibrahim DY, Sun H. Somatic Malignant Transformation of a Testicular Teratoma: A Case Report and an Unusual Presentation. Case Rep Pathol. 2019;2019:5273607. https://doi.org/10.1155/2019/5273607

2. Cabral FC, Krajewski KM, Rosenthal MH, Hirsch MS, Howard SA. Teratoma with malignant transformation: report of three cases and review of the literature. Clin Imaging. 2014;38(5):589-593. https://doi.org/10.1016/j.clinimag.2014.04.011