Postrelapse Prognostic Factors in Nonmetastatic Osteosarcoma: A Single-institution Experience.

Abstract

The purpose of this study was to analyze the prognostic factors that influence postrelapse survival (PRS) in children and adolescents with initial localized high-grade osteosarcoma. This is a retrospective evaluation of patients aged 21 years and below with nonmetastatic high-grade osteosarcoma treated at our institution from 1985 to 2011 who developed recurrent disease after achievement of an initial complete response (CR). PRS and postrelapse event-free survival (PREFS) analyses were performed using the Kaplan-Meier method and log-rank test. Multivariate Cox regression analysis was used to determine which variables were independently prognostic. Thirty-one patients were included. Median age at primary diagnosis was 13.7 years (range, 1.9 to 21.0 y). Median time to first relapse was 16 months (range, 3 to 36 mo). Fourteen patients achieved a second CR (CR2) after surgery±chemotherapy treatment. The 5-year PRS and PREFS were both 26% (95% confidence interval, 14%-49%), with a median follow-up of 99 months (range, 27 to 271 mo). Multivariate analysis showed that achievement of CR2 (P<0.001) and histologic response to first-line treatment (P=0.02) were significantly associated with PRS, whereas time to first relapse did not retain univariate significance. Achievement of CR2 and histologic response to preoperative first-line treatment are independent survival prognostic factors in osteosarcoma recurrence.