Le « growing teratoma syndrome » : une évolution méconnue des tumeurs germinales non séminomateuses traitées du testicule

“Growing teratoma syndrome” is a rare and often unrecognized complication of nonseminomatous germ cell tumors of the testis. It is defined by enlarging residual masses, frequently retroperitonal, composed exclusively by teratoma, during the course of chemotherapy. Complications of this syndrome are due to masses compression. Malignant transformation is also possible. “Growing teratoma syndrome” has a good prognosis when cured by complete surgical excision of the tumoral masses. We report the case of a “growing teratoma syndrome” presenting as a retroperitoneal mass occurring in a patient previously treated by orchiectomy and chemotherapy for a nonseminomatous mixed germ cell tumors of the testis without teratomatous component.