Prognosis of malignant sacrococcygeal germ cell tumours according to their natural history and surgical management

Abstract

Introduction: Malignant sacrococcygeal (SC) germ cell tumours (GCT) may be diagnosed as primary pelvic tumour or malignant recurrence of foetal SC teratoma (FSCT) operated during the neonatal period. In order to evaluate the difference between these two populations, the authors report their experience with SC-GCT registered in the French TGM 95 protocol.

Population and methods: The protocol comprised risk-adapted-chemotherapy (CT) followed by surgery. Standard risk (SR: localized tumour completely resected) had no adjuvant therapy. Intermediate-Risk (IR: localized tumour, incomplete or no initial surgery with αFP<15,000 ng/ml) received Vinblastine-Bleomycin-Cisplatin regimen; while High-Risk (HR: αFP > 15,000 ng/ml and/or metastases) received Etoposide-Ifosfamide-Cisplatin.

Results: Fifty-seven patients with SC-GCT, aged 0-80 months (median 16), were registered between 1995 and 2005. Nineteen patients had secondary SC-GCT after FSCT. All patients received CT: 17 IR and 1 SR after reevolution; 39 HR (25 with metastases). 51 patients underwent delayed surgery, which was incomplete in 8 patients.

Evolution: Seventy-two percent of the secondary SC-GCT had systematic biological follow-up. αFP increasing was the first presenting sign in 80% of the cases. Patients with secondary SC-GCT had a lower median αFP level at diagnosis, were less frequently classified as HR and received less CT. The two groups with secondary vs. primary SC-GCT had a statistically similar favourable outcome (Overall Survival: 93.8% vs. 86.2%; Event-Free Survival: 89.2 vs. 78.2%; p > 0.34 and >0.32), respectively, but with less burden of therapy.

Conclusions: SC-GCT has a good overall prognosis provided complete surgery is achieved and CT is administered to IR and HR patients. SC-GCT in patients followed by αFP after treatment for FSCT had less tumour extension than newly-diagnosed patients, probably because of earlier detection of the disease.