Postoperative infection and survival in osteosarcoma patients: Reconsideration of immunotherapy for osteosarcoma

There is controversy regarding the impact of infection on long-term prognosis in osteosarcoma patients. Clinical trials and experiments relating to this field could bring reconsideration of immunotherapy for osteosarcoma. The clinical records were reviewed of 125 osteosarcoma patients with a mean follow-up of 5.1 +/- 3.9 years (range, 0.5-19.8 years), and a review of the literature was also carried out. Chronic localized infections (but not systemic infection) were determined in 6 patients (4.8%). Similar chemotherapeutic regimens (P=1.00) and histological reactions (P=0.65) were observed in patients with or without infection. Tumor location of proximal tibia (P=0.04) was more common in infected patients. More amputations (P<0.001) were necessitated in infected patients due to uncontrolled infection. The 5-year overall survival rate and event-free survival rate in infected patients were 100%, which were significantly higher than that of the non-infected patients, of whom the rates were 54 and 43% respectively (log-rank test: total survival, P=0.01; tumor-free survival, P=0.01). Distant metastasis was an independent risk factor for survival determined by Cox regression analysis (P<0.001, 95 confidence interval, 1.59-3.98). These findings suggested infection was likely to have positive effects on survival in osteosarcoma patients, however, underlying mechanisms remain to be elucidated. Reconsideration of the association of infection and survival in osteosarcoma patients will help to explore novel therapeutic routes and targets in these patients.