Curative treatment of malignancies in the sacrum and lower lumbar spine frequently requires en bloc spinopelvic resection. There is no standard classification of these procedures. We present outcomes and a classification scheme with oncologic and reconstructive guidelines for spinopelvic tumors based on an analysis of 30 cases of en bloc resection and reconstruction performed with curative intent.

Mean follow-up of surviving patients was 38 months. Tumors included osteosarcoma (n=9), chondrosarcoma (n=6), chordoma (n=5), other sarcomas (n=5), neurogenic tumors (n=4), and local extension of carcinoma (n=1). Resections could be divided into 4 types. Type 1 resections (n=12) included a total sacrectomy with lower lumbar spine and bilateral medial iliac resections. Type 2 resections (n=6) included hemisacrectomy, partial lumbar spine excision, and medial iliac resection. Type 3 resections (n=9) encompassed external hemipelvectomy with hemisacrectomy and partial lumbar spine excision. Type 4 resections (n=3) encompassed external hemipelvectomy, total sacrectomy, and lumbar spine excision.

For each resection type, we have developed staged surgical approaches to allow resection with wide margins and reconstruction of spinopelvic continuity. Tumor free margins were achieved in all cases. Perioperative mortality was 3/30. Seven additional patients have died of disease, two died of other causes, two are alive with disease, and 16 have no evidence of disease. 13/18 surviving patients are independent in their activities of daily living.

In our practice en bloc excision and reconstruction of spinopelvic neoplasms may be classified into four types. For each type, we have devised surgical treatment guidelines to allow for wide resection and reconstruction of spinopelvic continuity. Long term survival and independent function can be achieved in this challenging patient population. This represents the first standardised classification of oncologic spinopelvic resections and reconstructions.