Impact of Prior Cancer on the Prognosis of Patients with Chondrosarcoma: A Population-Based Study of the SEER Database.

Background • Patients with prior cancer are generally exempt from cancer experiments. This research aims to describe the prevalence, clinical features, and effects of past malignancy among patients with chondrosarcoma. Methods • Chondrosarcoma patients diagnosed between 2010 to 2015 were collected from the SEER database. The propensity score matching method was used to reconcile the disparity in baseline attributes. Kaplan–Meier analysis was employed to explore the outcomes of prior cancer on overall survival. The proportional hazards assumption was used to certain whether the covariate matched the Cox regression model. The potential outliers were estimated by deviance residuals type. Results • A total of 1,721 unique individuals were collected, of those 284 (16.50%) patients had a history of cancer, with prostate cancer being commonly documented (n = 49, 17.25%). Approximately half of the previous tumors are diagnosed within 5 years before the diagnosis of chondrosarcoma. Chondrosarcoma patients with prior cancers have a lower survival rate than those without prior malignancy (P < .001). A multivariable Cox analysis reveals that past cancer is a distinct risk factor for lifespan (hazard ratio = 2.489, P < .001). Conclusion • This study initially discovered that chondrosarcoma patients with past cancer have a bad prognosis. Different types of past cancer have varying effects on survival. We urgently propose that cancer trial exclusion criteria be set specifically by cancer classification, rather than accepting the unchangeable criterion for default. [ABSTRACT FROM AUTHOR]