Bone metastases in germ cell tumor patients.

Purpose: Little data exist on characteristics, treatment, and outcome of patients with bone metastases from germ cell cancer.
Methods: A total of 434 patients with poor prognosis germ cell cancer, who underwent primary high-dose chemotherapy (HD-CTX) within two phase II trials, were retrospectively analyzed.
Results: 40 patients (9%) presented with primary bone metastases. Bone metastases were significantly more frequently observed in patients with primary mediastinal tumors, yolk sac tumor histology, and synchronous liver metastases. Overall response rate to HD-CTX was 85%. 20% of patients underwent consolidating radiotherapy, and 10% had resection of bone metastases revealing necrosis in all cases. Progression-free survival rate after primary treatment was 63% and, including salvage treatment after first relapse, overall long-term survival rate was 75%. Four patients (0.9%) relapsed with isolated bone metastases, all with bone metastases at primary diagnosis. None had previously received surgery or radiotherapy and all died within 1 year. 10 patients with primary bone metastases showed recurrences at other localizations. No patient relapsed with bone plus other metastases or with de novo bone metastases.
Conclusions: Bone metastases were associated with a primary mediastinal nonseminoma, yolk sac histology, and liver metastases at first diagnosis. In this cohort of patients receiving HD-CTX as first-line treatment, 63% achieved long-term progression-free survival. Skeletal relapses were rare, but showed dismal outcome.