How to Treat and Reconstruct the Pelvis After Chondrosarcoma Resection: Indications and Results at Medium- and Long-term in a Series of 34 patients.

Pelvic chondrosarcomas (CS) present complex diagnostic and therapeutic challenges due to their insidious onset and deep anatomical location. This study analyzes clinical, surgical, oncological, and functional outcomes in a consecutive series of 34 patients treated with wide resection, with the aim of proposing a surgical decision-making flowchart based on tumor localization. All patients with pelvic CS treated with wide resection between February 2005 and December 2021 were retrospectively reviewed. Epidemiological data, imaging, surgical details, histology, complications, oncologic outcomes, and functional results were collected. Tumor localization followed the Enneking and Dunham classification. Preoperative biopsy underestimated tumor grade in over 50% of cases. Wound infection was the most common complication (64.7%) and leading cause of perioperative mortality. Surgical Duration correlated with complication risk. Five-year overall survival was 60.2%, significantly influenced by age and histological grade. Local recurrence occurred in 10.3% of cases, associated with higher-grade tumors. Functional outcomes varied by resection site, with better scores in type I and III resections. Reconstruction strategies were adapted to anatomical site, tumor extension, and patient condition. Histological grade and age are key prognostic factors in pelvic CS. Wide resection remains essential due to frequent underestimation of tumor aggressiveness. Surgical approach and reconstruction should be tailored to tumor location to optimize oncologic control and functional outcome. A flowchart is proposed to guide surgical planning. Larger, more specific series are recommended to attain statistical significance and validate our findings and protocol.