Treatment of adult osteosarcoma - single-center results in 47 patients

Fourty-seven adult patients (median age 24 years; 16-66 years) with the diagnosis of osteosarcoma were treated at Hannover University Medical School between 1980 and 1991 according to the consecutive protocols of the Osteosarcoma Study Group (COSS-80 - COSS-86) irrespective of the fulfilment of study entry criteria. Patients received preoperative chemotherapy followed by surgical resection and adjuvant postoperative chemotherapy. Thirty-seven patients (79%) were treated for local tumors and 10 patients (21%) presented with disseminated metastatic disease. Twenty-one patients (45%) did not fulfil official study entry criteria. Thirty-four patients (72%) achieved an NED-status after therapy, 13 patients (28%) still had metastases and/or unresectable tumors. Seventeen of 34 patients (50%) relapsed after a median time of 18.5 months. Only 1 of 10 patients presenting initially with metastatic disease could be rendered long term tumor-free. The median overall survival of all patients was 42 months with a 2-year-survival rate of 64%. The projected 5-year-survival after a median follow-up of 59 months (8-121 months) was 49%. The presence of metastatic disease at initial diagnosis (p=0.04), an elevated alkaline phosphatase level at diagnosis (p=0.05), histologically 'poor response' to preoperative chemotherapy (p=0.04) and non-fulfilment of COSS-study entry criteria (p=0.046) were significantly worse prognostic factors during univariate analysis. The treatment results in unselected adult patients with osteosarcoma are inferior to those reported for patients included into osteosarcoma treatment study protocols. However, appoximately half of all patients (45%) seen at a large single center did not fulfil the eligibility criteria as official study patients. Even in these non-study patients the use of preoperative and/or adjuvant chemotherapy significantly improved survival compared to historical controls treated by surgery alone (58% and 38% 2- and 5-year-survival rates, respectively). The prognosis of patients with synchronous metastases at diagnosis remains poor despite the inclusion of chemotherapy into treatment strategies.