Introduction
Germ cell tumors (GCTs) are formed by aberrant migration of primitive germ cells arising in midline sites including brain, head/neck, mediastinum, gonads, retroperitoneum, sacrococcygeal region and vagina. GCTs are classified as gonadal and extragonadal germ cell tumors on the basis of origin. Sacrococcygeal GCT represents approximately 40% of primary extragonadal and extracranial germ cell tumors (EGCTs) among children[1]. Most pediatric tumors stemming from the region are benign teratomas followed by malignant yolk sac tumor (endodermal sinus tumor). Sacrococcygeal yolk sac tumors (SYSTs) are generally characterized by external mass growing around the sacrum and coccyx accompanied by elevation of AFP. A certain proportion of patients still developed local relapse although they received a first-line multidisciplinary treatment. Most of clinical explorations of sacrococcygeal GCT were confined to few case reports. The prognostic factors in relation with sacrococcygeal GCTs were poorly understood.
Here, we studied the relapse-free survival (RFS) rates, prognostic factors, and therapeutic effect of salvage treatment in a retrospective cohort of patients with SYST. Finally, we evaluated the combined prognostic factors of clinical significance on RFS.