Clinico-histologic parameters of osteosarcoma patients with late relapse

In total, 33 patients had a documented relapse 5 years or more after diagnosis. Half of the patients had good response (⩾90% necrosis) to pre-operative chemotherapy and the other half a poor response (<90% necrosis) and late relapses seemed to be more frequently proportionately in those who had a good initial response to chemotherapy. The occurrence of late relapse did not appear to be associated with age or gender. Although not statistically significant, there was a trend for patients with a chondroblastic subtype of osteosarcoma, or a location in the tibia or fibula, to have a higher risk for late relapse.