Métastase rétropéritonéale d'une tumeur testiculaire sous la forme d'un tératome mature avec transformation en adénocarcinome

A 41-year-old patient, with a medical history of embryonal carcinoma treated by orchidectomy at the age of 27, presented with abdominal pain. Serum alphafetoprotein, β-HCG and CEA levels were normal. MRI showed a cystic retroperitoneal lesion with septation, measuring 20 cm. He underwent a surgical resection. Histology revealed an adenocarcinoma arising on a mature multitissular teratoma.