Epidemiology and Chemosensitivity of Primary Malignant Bone Tumors at a Teaching Hospital in South Africa: A 5-Year Retrospective Analysis.

BACKGROUND Primary malignant bone tumors (PMBTs) are rare. The incidence of PMBTs varies by geographical location. In our African context, osteosarcoma is the most common PMBT seen; however, there is a variable representation of other PMBTs, likely due to some risk factor in the involved environment. PMBTs have not been studied concerning their geographical location and the role the environment can play as a risk factor. Our study aimed to retrospectively review children and adults treated for PMBTs at our center between 2016 and 2021. MATERIAL AND METHODS We performed a records review of patients treated for primary malignant bone tumors over 5 years. Admission, surgery, and laboratory records were searched for data extraction and analyzed using Microsoft Excel and Stata 18.0. RESULTS A total of 123 patients' records were retrieved; 91% were African, and 58.5% were female. The mean age for our cohort was 35.38 years. Osteosarcoma was the most common PMBT, followed by multiple myeloma and chondrosarcoma, in that order. Most of our patients with PMBTs reported pain as their main symptom at presentation. The overall chemosensitivity rate was at a low of 33%, due to poor compliance, while Ewing sarcoma was the most chemosensitive tumor in our cohort. CONCLUSIONS The most common PMBT at our hospital is osteosarcoma. There were variations in the incidence of the other PMBTs, in keeping with the literature. We had poor patient follow-up, leading to a poor chemotherapy response analysis. Our patients also had negligible knowledge of exposure to agricultural pesticides.