Cyclin D1 expression and facial function outcome after vestibular schwannoma surgery.

HYPOTHESIS: The proto-oncogen cyclin D1 has been implicated in the development and behavior of vestibular schwannoma. This study evaluates the association between cyclin D1 expression and other known prognostic factors in facial function outcome 1 year after vestibular schwannoma surgery.

METHODS

Sixty-four patients undergoing surgery for vestibular schwannoma were studied. Immunohistochemistry analysis was performed with anticyclin D1 in all cases. Cyclin D1 expression, as well as other demographic, clinical, radiologic, and intraoperative data, was correlated with 1-year postoperative facial function.

RESULTS

Good 1-year facial function (Grades 1-2) was achieved in 73% of cases. Cyclin D1 expression was found in 67% of the tumors. Positive cyclin D1 staining was more frequent in patients with Grades 1 to 2 (75%) than in those with Grades 3 to 6 (25%). Other significant variables were tumor volume and facial nerve stimulation after tumor resection. The area under the receiver operating characteristics curve increased when adding cyclin D1 expression to the multivariate model.

CONCLUSION

Cyclin D1 expression is associated to facial outcome after vestibular schwannoma surgery. The prognostic value of cyclin D1 expression is independent of tumor size and facial nerve stimulation at the end of surgery.