Autologous stem cell transplantation in patients with extragonadal germ cell tumors: A single center experience

Introduction Testicular cancer is the most common solid malignancy in men aged 15-35 years, 95% of which are germ cell tumors (GCT) (1). GCT is primarily located in the gonadal region and rarely occurs in an extragonadal area such as the mediastinum and retroperitoneum. Extragonadal GCT (EGGCT) are formed by malignant transformation of gonadal cells that have not completed their migration during embryogenesis without a gonadal primary mass in ultrasonographic evaluation (2). EGGCT accounts for 2-5% of all GCT and has an approximate incidence of 1/1,000,000 (3). Although EGGCT has similar histological, serological and cytogenetic characteristics as gonadal GCT, their behavior is different clinically and biologically. EGGCT has a worse chemosensitivity and prognosis than gonadal tumors (4,5). The treatment of EGGCT patients is similar to the treatment of gonadal GCT, and after histological separation as seminoma and non-seminoma, chemotherapy (CT) is applied according to risk classification. Surgical resection is also performed in patients with residual tumors. This multimodal treatment increases efficacy and survival (6,7). There is no standard salvage CT treatment for relapsed/refractory EGGCT patients. Autologous DOI: 10.4274/gulhane.galenos.2019.899 ORIGINAL ARTICLE