We observed that the extent of adhesion of the tumor to the brainstem and facial–acoustic nerve during surgery was the important risk factor that affected the total resection rate of tumor and the preservation rate of facial and acoustic nerve function; therefore, candidate variables including sex, age, maximum diameter of tumor, tumor texture, Ki-67, peritumoral edema, Samii classification, and tumor blood supply were analyzed. This evidence concerns the gene MKI67 and neoplasm.