A 20-year-old male presented with persistent right testicular pain. Following ultrasound detection
of testicular nodules and biopsy for intraoperative consultation which yielded germ cell tumour, he
underwent radical orchidectomy. A predominantly whitish cyst and a lobulated, variegated nodule
were identified. Histology showed a mature cystic teratoma with a focus of infiltrative epithelioid
cells containing eosinophilic cytoplasm and pleomorphic nuclei, invading ectatic vessel wall
associated with fibrinoid change. These cells were positive for cytokeratin, human placental lactogen
and inhibin, while negative for Melan-A, p63 and alpha-fetoprotein, consistent with placental site
trophoblastic tumor (PSTT). The variegated nodule was a mixed germ cell tumour composed of
embryonal carcinoma and immature teratoma. Aside from choriocarcinoma, primary trophoblastic
tumors such as PSTT, which are derived from intermediate trophoblasts, are extremely rare in the
testis. Aside from a case of pure testicular PSTT, 2 other cases have been described in association
with germ cell tumour, of which one is a mature teratoma with PSTT that demonstrated gain of
chromosome 12p. The other presented with PSTT in retroperitoneal recurrence of a testicular mixed
germ cell tumour. We discussed the features of this tumour in the testis and important differentials
in its diagnosis.