Advanced Technologies for the Treatment of Brain Stem Tumors

Summary

Very few cases of surgical treatment of brain stem neoplasms have been registered in the literature. The intrinsic tumors are often treated by radiation therapy only without biopsy which is considered too hazardous, treatment being limited to few cases (evacuation of an intrinsic cyst). In the tumors originating from the brain stem and bulging out from the axis only the extrinsic part is generally removed. More recently the introduction of new technologies (NMR, intraoperative ultrasonography, Laser, CUSA) has modified the surgery of these kinds of tumors. The main advantages offered are: a) a safe aggression of the brain stem; b) the possibility to perform a correct histologic diagnosis; c) a reduction of the fields and doses of postoperative radiation therapy.

Our series consisted of9 operated tumors: 5 intrinsic (4 solid and 1 cystic) and 4 protruding out from the axis. Histology revealed a pilocytic astrocytoma in 4 cases, an anaplastic astrocytoma in 4 cases and a metastasis in one case. All patients were submitted to X-ray therapy after surgery.

Patients with anaplastic astrocytoma died between 5 to 12 months after treatment. Patients with pilocytic astrocytoma are still alive after 5 and 3 years and 1 year and able to return to school.

The results of a comparative group treated only with radiation therapy shows a survival time similar to that of operated patients, ranging from 15 to 47 months, however, a remarkable period of time for clinical improvement is required (Bray et al. 1958).