Posters— Medical Oncology

OSTEOSARCOMA OVER THE AGE OF 40

R J Grimer on behalf of the European Musculoskeletal Oncology Society The Royal Orthopaedic Hospital Oncology Service, Bristol Road South, Birmingham, U.K. B31 2AP Telephone: (+44) 121-685-4150 Fax: (+44) 121-685-4146

ABSTRACT: Purpose: To ascertain whether patients over the age of 40 have a different disease pattern and prognosis to younger patients with osteosarcoma. Background: Osteosarcoma is principally a disease of adolescents but 13% of all patients with osteosarcoma will be over the age of 40 - and to date have been excluded from most national trials of treatment of osteosarcoma. A collaborative study from EMSOS has collected data on these patients.

Material: Data on 486 patients have been contributed from 13 centres. The ages ranged from 40 to 89 with a mean of 54. 275 were male and 211 female. The most common sites were femur followed by pelvis and tibia and 84 had a secondary osteosarcoma - 42 related to Paget’s disease and 42 secondary to radiation. 30 patients had “low grade” osteosarcoma, the remainder having high grade tumours of which 57 had metastases at presentation. Almost half the patients had chemotherapy . Surgery consisted of amputation in 118 and limb salvage surgery in 252 with 113 having endoprostheses and 15 having allografts. 184 were felt to have had adequate surgical margins and 102 had close or inadeqaute margins. 85 patients had radiotherapy of which 41 were palliative.

Results: The overall survival rates were 37% at 5 years falling to 27% at 10 years. The 5 and 10 year survival rates for stages 1,2 and 3 turnours were respectively: 78% & 62% 41% & 28%; 9% & 9%. Patients over the age of 60 and patients who did not have adequate treatment not surprisingly fared worse, as did all patients with secondary osteosarcoma. The median survival time for patients with Paget’s osteosarcoma was 7 months and for radiation sarcoma was 12 months. For patients with stage 2 turnours the effect of age was such that the 5 year survival rates were 45% for those less than 60 and 28% for those over 60. There was little information about effectiveness of chemotherpy but there was a trend for those with a good response to fare better than those without. Local recurrence arose in 7% of those having amputations and 22% of those having limb salvage surgery. It was closely related to margins of excision with 27% of those having inadequate margins developing local recurrence compared to 12% of those with adequate margins.

Conclusion: Osteosarcoma over the age of 40 requires just as much care and multidisciplinary working as osteosarcoma in the younger age group. Patients with secondary osteosarcoma have a dismal outlook. Chemotherapy and effective surgery remain the mainstay of treatment.