Pure yolk sac tumour, post-pubertal type, arising from cryptorchid testes.

Yolk sac tumour (YST), the most common germ cell tumour (GCT) in infants and children, accounts for 80% of GCTs in this age group. 1 It is observed in only 2.4% of adult patients in their pure form since up to 42% of mixed GCTs have some component of the yolk sac. 2 We present a 46-year-old cryptorchid man who presented with complaints of abdominal lump, pain and altered bowel habits since 1 month. CT scan of the abdomen revealed a mass arising from the pelvic cavity with feeders predominantly from the left gonadal vessel. Mass was excised via exploratory laparotomy and sent for histological examination. Microscopic examination was suggestive of pure YST. Immunohistochemistry stained positive for cytokeratin, placental-like alkaline phosphatase, Glypican 3 and alpha fetoprotein. The patient succumbed prior to commencing chemotherapy. Pure YSTs of post-pubertal origins are extremely rare and are more aggressive than their prepubertal counterparts.