Outcome of surgical treatment for pelvic chondrosarcoma of 165 cases

Abstract

Objective To review the long-term oncologic and functional outcomes of surgical treatment for pelvic chondrosarcoma at a single institution to further delineate surgical strategy of resection and function reconstruction.Methods All of 165 patients with pelvic chondrosarcoma that had been surgically treated between July 2000 and Dec 2013 were reviewed retrospectively.There were 102 male and 63 female patients who had a mean age of 43.5 (range,13 to 75) years.The resection type included Type T 16,type Ⅱ 18,type Ⅲ 11,type Ⅰ+Ⅱ 19,type Ⅱ+Ⅲ 63,type Ⅰ+Ⅳ 15,type Ⅰ+Ⅱ+Ⅲ 10 and type Ⅰ+Ⅱ+Ⅳ 13 cases.The pathology diagnosis was grade Ⅰ in 15,grade Ⅱ in 88,grade Ⅲ in 20,dedifferentiated in 28,mesenchymal in 12 and clear cell chondrosarcoma in 2 patients.Nine cases were secondary lesion following multiple exostoses.114 patients received no previous treatment while others were referred due to recurrent tumor.En bloc resection was achieved in 142 patients and intralesional resection in 23 cases.Twelve patients had a hemipelvectomy to achieve local tumor control,whereas 153 patients underwent a limb-salvage procedure.Spinal screw-rod system was used to reconstruct anterior pelvic ring after ilium resection.Modular hemipelvic endoprosthesis was utilized to reconstruct periacetabular defect after tumor resection while no reconstruction was performed after ischium and pubis resection.Results The median duration of follow-up was 54.1 (range,l0 to 159) months.147 (89.1％) patients were alive at the final follow-up,seven of which were alive with tumor.The estimated 5-year survival was 81.5％.Thirty-three patients (20％) had local recurrence,and twenty (12.1％) had lung metastasis.Recurrent case,sacroiliac joint involvement and intralesional resction were three risk factors for postoperative recurrence.Patients who received type Ⅱ+Ⅲ resection and reconstruction had a mean functional score of 23 according to MSTS 93.The mean MSTS 93 for patients with type Ⅰ+Ⅱ and type Ⅰ+Ⅱ+Ⅳ resection and reconstruction was 18.The wound complication rate was 15.8％.Two aseptic loosening and 2 pubic connection plate breakage were observed in hemipelvic endoprosthesis reconstruction.Conclusion Tumor grade correlates with overall or disease-free survival.For low-grade chondrosarcoma,adequate surgical margin can provide long-term local control while for high-grade cases,distant metastasis is the main case of treatment failure.Adequate surgical margin can be achieved in cases with acetabulum involved.However,aggressive surgical resection of pelvic chondrosarcoma still remains as a challenge for orthopaedic oncologists when the tumor invades the iliosacral joint,which necessitates careful preoperative plan and skilled surgical techniques. Key words: Pelvis; Chondrosarcoma; Treatment outcome