Prognostic value of tumor size, metastases, extension into bone, and increased tumor marker in children with malignant sacrococcygeal germ cell tumors: a prospective evaluation of 71 patients treated in the German cooperative protocols Maligne Keimzelltumoren (MAKEI) 83/86 and MAKEI 89.

Abstract

To evaluate the prognostic value of metastases, extension into bone, and alpha-fetoprotein (AFP) elevation in children with malignant sacrococcygeal germ cell tumors (GCTs) prospectively collected in two cooperative Maligne Keimzelltumoren (MAKEI) protocols (83/86 and 89). Between October 1983 and October 1995, 76 of 210 registered patients with sacrococcygeal primaries presented either with pure yolk sac tumor, embryonal carcinoma (EC), or yolk sac tumor and EC mixed with immature and mature teratoma elements. Stages T1 and T2 disease were diagnosed in 15 and 61 children, respectively, 41 patients had metastases, and 35 children presented with extension into bone. At diagnosis, 22 children had an AFP elevation of less than 10,000 ng/mL. Thirty-six children showed an AFP level between 10,000 and 100,000 ng/mL, and 12 patients had values of greater than 100,000 ng/mL. Five patients died of complication during treatment and were excluded from further evaluation. Seventy-one patients could be analyzed. The 5-year relapse-free survival rate (RFS, Kaplan-Meier) was 0.76 +/- 0.03 (54 of 71 patients; median observation time, 54 months after diagnosis). The RFS of patients with and without metastases was different, but not significantly so (0.71 v 0.82). The outcome of patients with extension into bone (n = 31) and without this extension (n = 40) was 0.71 versus 0.80 (RFS, 5 years). Above-normal AFP level had no prognostic significance (P =.52). In children with malignant sacrococcygeal GCTs treated with an intensive, short-interval, platinum-based regimen, the stage, extent of metastases, extension into bone, and AFP level had no prognostic significance.