Abstract
Osteosarcomas represent a heterogeneous group of primary bone tumours that affect predominantly the long bones of patients in the first two decades of life. We aim to describe the secondary effects of a poor response (⋋90% necrosis) to chemotherapy on the effectivity of other treatment outcomes, local recurrence and survival rates.
182 cases of osteosarcoma with necrosis of less than 90% and no metastases at diagnosis have been seen at our institution over 24 years. There were 60 amputations. 122 patients underwent limb salvage, with 105 marginal margins and 17 contaminated. There was no difference in size or location between the two groups. In the 122 patients with LSS, 21 had adjuvant radiotherapy and 101 did not. In the entirety of patients with ⋋90% necrosis, survival was 64% at 2 years and 37% at 5 years. When LSS Marginal resections were compared with amputation there was a significant (P=0.006) difference in survival. LSS with a marginal margin had a 25% risk of LR. In these patients there was 25% survival, whereas the absence of a local recurrence, conferred a benefit of a 40% survival XRT was used in 21 of the 122 who underwent limb salvage. The decision to use XRT was made by the local oncologist at the treating unit. There was a 24% rate of recurrence in the XRT group and 25% with no XRT.
These data demonstrated that patients who had a poor response to chemotherapy and underwent an amputation faired poorly when compared to patients with LSS. There is a selection bias in patients selected to undergo amputation. Additionally, patients who underwent amputation had a lower rate of local recurrence, but still had a poorer survival when compared to LSS.