Spanish Multicenter Megaprosthesis Study (MEGAPROT) on 816 Tumor Prostheses: Main Results

(1) Background: The use of tumor megaprostheses faces challenges, but the published series are typically small and offer limited solutions. Our aim was to compile a large series; describe patient profiles and surgical techniques; analyze prosthetic survival identifying factors affecting survival; and provide a basis for future subanalyses. (2) Methods: This is a retrospective observational multicenter study that included patients with a tumor megaprosthesis in any anatomical location. Demographic, etiologic, and surgical variables were analyzed. Data on complications and survival were also collected. (3) Results: Our series includes a total of 816 prostheses (585 primary, 181 revision, and 50 second revision). The patients' mean age was 44.2 +/- 20.8 years. Primary surgeries were performed on the femur (n = 404; 69.1%), tibia (n = 79; 13.5%), humerus (n = 74; 12.6%), pelvis (n = 20; 3.4%), and scapula (n = 4; 0.7%). Survival following primary surgery was 73.3% at 10 years. No statistically significant differences were found with respect to survival from primary surgery between males and females (p = 0.194), between the different etiologies (p = 0.540), or between the lower and the upper limb (p = 0.618). In contrast, statistically significant survival differences were found when the type of fixation was analyzed (p < 0.001). (4) Conclusions: This study analyzed one of the largest series of patients treated with tumor megaprostheses, demonstrating their acceptable survival and validating them as a treatment option for bone tumors.