Is Surgical Resection of the Primary Site Associated with an Improved Overall Survival for Patients with Primary Malignant Bone Tumors Who Have Metastatic Disease at Presentation

Abstract

Background The management of primary malignant bone tumors in patients with metastatic disease at presentation remains a challenge. Although surgical resection has been a mainstay in the management of nonmetastatic malignant bone tumors, there is a lack of large-scale evidence-based guidance on whether surgery of the primary site/tumor improves overall survival in malignant bone tumors with metastatic disease at presentation. Questions/purposes (1) Is surgical resection of the primary tumor associated with improved overall survival in patients with primary malignant bone tumors who have metastatic disease at presentation? (2) What other factors are associated with improved and/or poor overall survival? Methods The 2004 to 2016 National Cancer Database (NCDB), a national registry containing data from more than 34 million cancer patients in the United States, was queried using International Classification of Diseases, 3rd Edition, topographical codes to identify patients with primary malignant bone tumors of the extremities (C40.0-C40.3, C40.8, and C40.9) and/or pelvis (C41.4). The NCDB was preferred over other national cancer registries (that is, the Surveillance, Epidemiology, and End Results database) because it includes a specific variable that codes for patients who received additional surgeries at metastatic sites. Patients with malignant bone tumors of the head or skull, trunk, and spinal column were excluded because these patients are not routinely encountered and treated by orthopaedic oncologists. Histologic codes were used to categorize the tumors into the following groups: osteosarcomas, chondrosarcomas, and Ewing sarcomas. Patients whose tumors were classified as Stage 1, 2, or 3 based on American Joint Commission of Cancer guidelines were excluded. Only patients who presented with metastatic disease were included in the final study sample. The study sample was divided into two distinct groups: those who underwent surgical resection of the primary tumor and those who did not receive any operation for the primary tumor. A total of 2288 patients with primary malignant bone tumors (1121 osteosarcomas, 345 chondrosarcomas, and 822 Ewing sarcomas) with metastatic disease at presentation were included, of whom 46% (1053 of 2288) underwent surgical resection of the primary site. Thirty-three percent (348 of 1053) of patients undergoing surgical resection of the primary site also underwent additional resection of metastases. Patients undergoing surgical Each author certifies that neither he, nor any member of his immediate family, has funding or commercial associations (consultancies, stock ownership, equity interest, patent/licensing arrangements, etc) that might pose a conflict of interest in connection with the submitted article. Each author certifies that his institution waived approval for the human protocol for this investigation and that all investigations were conducted in conformity with ethical principles of research.