Malignant bone tumors around the knee: A single-center experience

Abstract

Aim: This study aimed to determine the frequency of malignant bone tumors (primary and metastatic) seen around the knee in our region, the patients’ type and demographic characteristics, and the treatments’ outcomes. Material and Method: A retrospective analysis of the patients who were diagnosed and treated with histopathologically malignant tumors in the knee region in our hospital between 2004-2021 was performed from the hospital database. Patients’ complaints, demographic information, and diagnostic and imaging findings were examined. In addition, tumor types, tumor localization, and treatments applied were analyzed. Results: Malignant bone tumor was detected in 88 (35.7%) of 246 patients included in the study. The patients were 48 women and 40 men, with a mean age of 39.72±21.8 (6-76 years). A total of 88 patients were divided into the pediatric group (<18 years; n=39) and the adult group (≥18 years; n=49). The most common tumors were osteosarcoma in 54 (61.3%) and metastatic tumors in 22 (25%) patients. The most common localization of tumors was the distal femur with a rate of 75%. Metastasis was detected in 12 (18.2%) of 66 patients treated and followed up for primary malignant bone tumors. Limb sparing surgery was performed in 70 (79.5%), and various levels of amputation were performed in 14 (15.9%). Palliative radiotherapy was applied to two patients with metastatic lesions, while two patients who were in the neoadjuvant chemotherapy period died. The 5-year overall survival was 63.7%. Pediatric and adult age groups did not differ significantly in terms of survival (p=0.74), gender (p=0.585), and metastasis development (p=0.53). Conclusion: The knee is a region that requires attention regarding bone tumors around it. As malignant bone tumors are rarely seen around the knee, a misdiagnosis may be made, and appropriate treatment may be delayed. Although the first diagnosis to come to mind for patients presenting with knee pain is trauma and growing pains, it must not be forgotten that a tumor could be the cause.