Prognostic Factors in Patients with Conventional Chondrosarcoma: A SEER Database Analysis

Abstract

Background: Conventional chondrosarcoma, a rare type of bone tumor, is resistant to chemotherapy and radiation therapy. Thus, additional characteristics of this disease are needed to open other treatment modalities. The clinical investigation of chondrosarcoma is limited to small-series and single-institution studies. The Surveillance, Epidemiologic, and End Results (SEER) is the most complete and comprehensive database worldwide. This SEER database study aimed to collect clinicopathological features and determine the prognosis of patients with conventional chondrosarcoma. Methods: Clinicopathologic and survival data of 782 patients from 2010 to 2016 and 353 patients from 2007 to 2009 were downloaded and analyzed. Overall survival was analyzed using the Kaplan–Meier method and verified by univariable Cox regression. Independent prognostic factors were assessed using the multi-variable Cox regression hazards model. A nomogram was established and used to calculate the one-, three-, and five-year survival rates. Competitive risk models were established to identify the prognostic risk factors related to competitive endpoint events in patients with conventional chondrosarcoma. Results: In total, 361 extremities, 360 axial bones, and 61 cranial samples were collected from the 2010–2016 cohort. The median survival time of patients with conventional chondrosarcoma was 35 months, and the independent prognostic factors were sex, grade, surgery, AJCC_M age, and tumor size. Thereafter, a nomogram was established basing from those independent prognostic factors. The competitive risk model revealed no competitive risk for the cancer-specific endpoint event. The data from 2007 to 2009 were used to validate the results from 2010 to 2016 with general consistency. Conclusion: This retrospective study determined the prognostic factors in patients with conventional chondrosarcoma by using the Cox regression hazards model. A nomogram was established to help oncologists assess this rare malignant tumor with low heterogeneity.