Osteosarcoma of the mobile spine.

STUDY DESIGN: Retrospective case series. OBJECTIVE: Our goal was to assess whether en bloc resection had an impact on survival. SUMMARY OF BACKGROUND DATA: Osteogenic sarcoma occurs rarely in the mobile spine, but when it does, the prognosis is poor. Wide resection is recommended for osteogenic sarcoma of the extremities, but wide resection is difficult and often dangerous in the spine. The goal of this study was to examine whether en bloc removal of osteogenic sarcomas in the mobile spine improves survival. METHODS: We performed a retrospective review of all cases of high-grade, osteogenic sarcoma of the mobile spine treated with high-dose methotrexate and adrimaycin-based chemotherapy between 1985 through 2005. There were 9 male patients and 8 female patients. Patients were followed for a median of 38 months or until death, and surviving patients were followed for a minimum of 6.4 years. Patients were grouped on the basis of whether they underwent en bloc spondylectomy. The Enneking stage and Weinstein, Boriani, and Biagini stage, as well as the pre- and postoperative Frankel grades, were collected on all patients. Local recurrence and metastasis data were collected for all patients. Overall survival was calculated using Kaplan-Meier methods with the log rank test utilized to evaluate the effect of en bloc resection on survival. RESULTS: Twelve (71%) of 17 patients with osteogenic sarcoma of the mobile spine died. Median disease-specific survival for the entire cohort was 38.1 months (standard error 29.6; 95% confidence interval 0-96). Nine patients underwent en bloc resection. Median overall survival for patients after en bloc resection was 77.3 months (standard error 62; 95% confidence interval 96) versus 17 months (standard error 6.5; 95% confidence interval 4-29.6) (P = 0.09). Eleven (65%) of 17 patients developed pulmonary metastasis, and 9 of those 11 died from their disease (P = 0.04). Six (35%) patients developed a local recurrence, and all 6 died from their disease (P = 0.07). CONCLUSION: Osteogenic sarcoma of the mobile spine presents a significant challenge, and most patients die from their disease in spite of aggressive surgery and chemotherapy. Metastastic disease is associated with a worse prognosis. There is a trend toward improved survival with en bloc resection when compared with intralesional resection. Osteogenic sarcoma of the mobile spine is rare and historically has a very poor prognosis. We reviewed our cases of osteogenic sarcoma of the mobile spine to assess whether modern en bloc resection improved survival. Survival remains poor, but there is a trend toward improved survival with en bloc resection.