Platinum-based chemotherapy of primary extragonadal germ cell tumours: TheHellenic Cooperative Oncology Group experience

Extragonadal germ cell tumours (EGCT) are uncommon, most frequently arise i n the mediastinum and retroperitoneum and have variable responses to platin um-based chemotherapy. A retrospective analysis was performed on 38 patient s with EGCT treated with cisplatin-based (CDDP) or carboplatin-based (CBDCA ) chemotherapy between 1984 and 1998. Twenty-four patients had nonseminomat ous germ cell tumours (NSGCT) and 14 seminoma. Twenty-two tumours arose in the mediastinum (13 nonseminomas, 9 seminomas) and 16 in the retroperitoneu m (11 NSGCT, 5 seminomas). Initial surgery included complete resection in 1 patient, biopsy in 27 patients and debulking surgery in 10 patients. Compl ete response rates with chemotherapy +/- surgery were as follows: mediastin um 14 of 21 (66.66%) patients (8 of 12-75% NSGCT, 6 of 9-66.66% seminomas) and retroperitoneum 14 of 16 (87.5%) patients (9 of 11-81.81% NSGCT, 5 of 5 -100% seminomas). One patient who underwent complete resection of a mediast inal malignant teratoma combined, received PVB chemotherapy on an adjuvant basis a nd remains alive and disease-free. Th ree additional seminoma patie nts who achieved partial response after chemotherapy remain alive and disea se-free following mediastinal radiotherapy. All 14 patients with extragonad al seminomas remain alive with no evidence of disease at a median follow-up of 49 months (range 7-164), giving an overall survival of 100%. Nine of 13 (69.23%) patients with mediastinal NSGCT are long-term disease-free at a m edian follow-up of 43.5 months (range 7-152). Nine of 11 (81.81%) patients with retroperitoneal NSGCT remain alive and disease-free at a median follow -up of 56 months (range 14-110). Complete surgical resection of residual ma ss was undertaken in 10 patients (3 seminomas, 7 nonseminomas). The histolo gy revealed necrosis/fibrosis in 6 patients (3 seminomas, 3 NSGCT) and viab le cancer in 4 patients. Patients who had viable malignant cells in the res ected specimens received two more courses of VelP chemotherapy. None of our patients had relapsed at the time of this analysis. None of our 6 patients who underwent testicular biopsy (1 patient) or orchiectomy (5 patients) du e to suspicious ultrasound of the testis were found to have testicular tumo ur or fibrotic scar. In conclusion, this retrospective analysis showed sign ificant responses in patients with either mediastinal or retroperitoneal NS GCT treated with CDDP- or CBDCA-based chemotherapy +/- surgery. All patient s with extragonadal seminomas remain alive with no evidence of disease, reg ardless of the site at presentation.