What are the factors that affect survival and relapse after local recurrence of osteosarcoma?

BACKGROUND: Despite improvements in treatment of primary osteosarcoma, treatment of patients who have local recurrence is not well defined. QUESTIONS/PURPOSES: We asked: (1) What are the 5- and 10-year overall survival rates of patients with osteosarcoma who have a local recurrence? (2) What factors are associated with better survival after a local recurrence? (3) Does chemotherapy affect overall survival after local recurrence? (4) What are the rates of rerecurrence after amputation and with limb salvage?
METHODS: We reviewed 45 patients with nonmetastatic conventional high-grade osteosarcoma who had local recurrence between 1985 and 2007, during which time 461 patients were treated for the same disease. Seven patients with known local recurrence were lost to followup and not included in our study. The median age of the patients was 18 years, and minimum followup was 2 months (median, 39 months; range, 2-350 months). The primary tumor was located in the extremity in 36 patients and the pelvis in nine. The median time from initial surgery for resection or amputation of the primary tumor to local recurrence was 18 months (range, 2-149 months). Ten recurrences developed in bone and 35 in soft tissue. In 21 of the latter cases, the soft tissue recurrence was undetectable on conventional radiographs. Prognostic factors for overall patient survival after recurrence were evaluated by Kaplan-Meier survival and Cox multivariate analyses.
RESULTS: Overall postrecurrence patient survival was 30% at 5 years and 13% at 10 years. Cox multivariate analysis revealed that concurrent metastasis (relative risk = 4, p = 0.003) and recurrent tumor size 5 cm or larger (relative risk = 13, p < 0.0001) were independent predictors of worse survival. With the numbers available, treatment with chemotherapy after local recurrence was not associated with better survival (p = 0.54). Nine patients had a second local recurrence, and the actuarial risk of rerecurrence was 34% at 5 years. There was no difference in the frequency of rerecurrence between patients treated by amputation and wide local excision (p = 0.23).
CONCLUSIONS: The long-term prognosis of patients who have local recurrence of osteosarcoma is poor. Followup beyond 5 years is essential, because the disease can have a protracted course. Most recurrences develop in soft tissue and are difficult to see on plain radiographs alone. The size of the recurrence and presence of metastasis were independent prognostic factors, suggesting that early detection may be important. Chemotherapy did not have a significant effect on survival, and surgical eradication of recurrence with wide margins may be critical to maximizing the chances for survival.