'Burned-out' syndrome of testicular teratoma: A case report.

The majority of testicular tumors are germ cell tumors (GCTs) which, although rare, frequently present in young adults. In exceptional circumstances, spontaneous regression of the primary tumor occurs. The appellation 'burned-out' is applied to situations in which a metastatic GCT is found to be present, accompanied by histological regression of the primary testicular lesion. It is of crucial importance that a clinical examination of the testis is performed, and scrotal sonography is essential in the preliminary diagnosis of such neoplasms. In the present case report, a burned-out, non-seminomatous testicular GCT case is described. A CT scan revealed that a 29-year-old male patient who was experiencing loss of weight and appetite had retroperitoneal and mediastinal masses. A testicular examination did not reveal the presence of any palpable lesion, and an ultrasound examination of the scrotum disclosed a normal left testis and an atrophic right testicle with heterogeneous architecture, but with no evidence of a tumor. Chemotherapy was administered to the patient following surgical intervention into the retroperitoneal and mediastinal mass. It is evident that it remains problematic to accurately differentiate between a primary retroperitoneal tumor and a metastatic testicular tumor with an occult testicular primary or a 'burned-out' testicular cancer. The burned-out phenomenon is a rare occurrence, and further research into its pathogenesis is required. Both the rarity of this phenomenon and the difficulties encountered in diagnosis prompted the writing of the present case report, especially considering that teratomas are categorized as belonging to the histology group that shows the least likelihood of regressing.