Osteosarcoma of the spine: experience in 26 patients treated at the Massachusetts General Hospital.

BACKGROUND CONTEXT

Because of the low incidence, treatment recommendations for spinal osteosarcoma are guided by the results of small series and case reports. Many include patients who presented for treatment over the course of three to four decades.

PURPOSE

The goal of this investigation was to report the treatments, results, and overall survivorship of 26 patients treated for osteosarcoma of the spine at a single institution.

STUDY DESIGN

Retrospective prognostic series (Level III evidence).

PATIENT SAMPLE

Twenty-six patients treated at a single center for osteosarcoma of the spine over a 26-year period.

OUTCOME MEASURES

Estimation of patient survival, local recurrence, and the presence of metastatic disease.

METHODS

We performed a retrospective review of cases of osteosarcoma involving the spine treated at our institution between 1982 and 2008. Medical charts, radiology reports, pathology reports, and operative notes were reviewed for all patients. Available imaging studies were also reviewed. The log-rank test was used to compare baseline differences between groups. Survivorship analysis was performed using Kaplan-Meier methodology. The effect of Paget osteosarcoma, type of resection, presence of local recurrence, tumor size, surgical margins, and metastases on overall survival were also investigated using the log-rank test.

RESULTS

Twenty-six patients were included for review in this study. Twenty individuals were treated surgically, and 24 were treated with radiation with a mean dose of 62.2 Gy (range 20-84.7 Gy). Twenty-five patients received chemotherapy. Of those treated surgically, seven received en bloc resection. The median overall survival for all patients in our series was 29.5 months (standard error 14.7, 95% confidence interval 0.6-58). Local recurrence developed in 7 patients (27%), and metastasis occurred in 16 individuals (62%). Patients with Paget osteosarcoma had worse overall survival (p<.001).

CONCLUSIONS

Results presented here confirm a poor prognosis for patients with spinal osteosarcoma. Although combination therapies, including surgery, chemotherapy, and high-dose radiation, achieve adequate short-term survival, the 5-year mortality rate remains high.