[The surgical treatment of primary malignant bone tumors of pelvis].

OBJECTIVE To evaluate the surgical treatment effect of primary malignant pelvic bone tumors. METHODS Retrospective study was carried out in 79 patients with primary malignant pelvic bone tumors treated surgically and followed up regularly between October 1992 and July 2007. In this cohort, 23 tumors were low-grade malignant of I B, and 56 tumors were high-grade malignant of II B. According to the preoperative diagnosis and the effect of chemotherapy, different methods of tumor resection and reconstruction were applied respectively. Surgical specimens were evaluated postoperatively for the surgical margins in accordance with Enneking's criteria. Functional results were assessed by MSTS system during follow-up. The mean time of follow-up was 28.6 months (range, 0-183 months). The minimum follow-up time in survival patients was 4 months. RESULTS Seventy limb-salvage surgeries including 28 reconstructions, and 9 hemipelvectomy were carried out. In limb-salvage group, the mean MSTS functional scores both were 15 points for patients with (range, 5-29 points) or without (range, 2-30 points) reconstructions. The overall local recurrence rate was 31.6% (25/79). Statistical difference (P = 0.023) of local recurrence rate was seen between low-grade (13.0%) and high-grade (39.3%) groups. While, there was no difference (P = 0.620) between limb-salvage group (30.0%) and hemipelvectomy group (44.4%). Significant difference (P = 0.014) in local recurrence rate was found between inadequate surgical margin (intralesional and marginal margin) group (38.1%) and adequate surgical margin (wide margin) group (6.3%). In 14 patients developed postoperative distant metastasis, 12 in local recurrence group which incidence was 48.0%, compared to 2 in no-recurrence group which incidence was 3.7%, and the difference was significant (P = 0.000). The overall survival rate was 70.9%. CONCLUSIONS Wide surgical margin is essential for successful resection of primary malignant pelvic bone tumors. How to choose and improve functional reconstruction is the focus of work in the future.