Malignant sacrococcygeal germ cell tumors in childhood: The Associazione Italiana Ematologia Oncologia Pediatrica (AIEOP) experience

Purpose: To evaluate clinical features at diagnosis, prognostic factors, and outcomes of malignant sacrococcygeal germ cell tumors (SC-GCTs) in patients enrolled in the Associazione Italiana Ematologia Oncologia Pediatrica (AIEOP) TCG 2004 protocol. Patients and Methods: A prospective analysis was conducted on all consecutive patients diagnosed with malignant SC-GCTs between January 2004 and May 2017. Patients with stage I underwent surgery and subsequent surveillance, the others received pediatric cisplatinum-etoposide-bleomycin (pPEB) regimen and eventual deferred surgery. Results: Of 45 patients, 35 were females. Age at diagnosis ranged from 1 day to 3.6 years (median 1.6 years); 26 were stage IV. Of 38 patients who underwent surgery, pathology revealed yolk sac tumor (YST) in 27 and teratoma + YST/embryonal carcinoma in 11, while seven patients were diagnosed based on imaging and elevated levels of alpha-fetoprotein (AFP). Of six patients approached with surgery, only one relapsed and was rescued with first-line chemotherapy. Overall, 38 out of 45 achieved complete remission, three a partial remission, and four were resistant. Ten out of 41 patients who entered remission later relapsed and nine were rescued with a second-line treatment. We observed a global failure percentage of 31% and a 5-year overall survival (OS) and event-free survival (EFS) of 95% and 69%, respectively. Conclusions: Chemotherapyis generally effective in malignant SC-GCTs, even though almost one-third of our patients experienced events salvageable with second-line treatment. Most of the relapses occurred within 1 year from diagnosis. A close follow up with serial AFP level monitoring should be done for at least 2 years after diagnosis.