Stereotactic biopsy in surgically inaccessible tumors with the use of "P.N." type frame

Abstract

Introduction: Stereotactic biopsy is unquestionably regarded as the gold standard for histopathological diagnosis of surgically inaccessible tumors. Tissue samples can be obtained by minimally invasive technique. Histopathological examination opens the door to oncological treatment of patients. Such procedures have been performed in the Neurosurgery Department, Jagiellonian University in Krakow since February 2003. The aim of this study is to evaluate the use of "P.N." type Frame (Tatramed, Slovakia) in verification of surgically inaccessible tumors.

Material and methods: Surgically inaccessible diffuse, deep-seated or located in eloquent areas tumors of cerebral hemispheres were diagnosed in 36 patients. In these cases 56 stereotactic biopsies were performed. The specimens of tumors were obtained with the aspiration method, according to coordinates derived from CT scan. The procedure was performed under local anesthesia in 17 patients and in 19 cases, it was performed under general anesthesia. The lesion was located in 13 cases in cerebral hemisphere infiltrating basal ganglia, in 13 cases tumors were diffused within one of the hemisphere but without involvement of basal ganglia, in 7 cases tumors were localized in eloquent areas, in 1 case in posterior commissure, in 1 case it was a tumor of corpus callosum and third-ventricle and in 1 case a tumor was multifocal.

Results: Material from the stereotactic biopsy has been examined neuropathologically. Astrocytomas II degree WHO were diagnosed in 8 cases, Astrocytomas III degree WHO in 12 cases, and Astrocytomas IV degree WHO in 10 cases. Metastatic Adenocarcinoma was diagnosed in 3 cases and in 3 cases a neoplasm was not found. The definite histopathological diagnosis was confirmed (in relation to the "intraoperational" one) in 91.7%. In 3 cases the increased intracranial pressure produced by tumor cyst was reduced by the use of biopsy. Patients with gliomas of III degree and IV degree WHO were treated by irradiation. Stereotactic biopsy in 11 cases (that is 44% of all cases) made the oncological treatment possible.

Conclusions: Stereotactic biopsy with the use of "P.N." type frame is a very safe and precise method making the histopathological diagnosis of inaccessible tumors possible. The size of tissue sample acquired with the use of "P.N." frame makes the use of standard histopathological techniques possible. Stereotactic diagnosis of some tumors made oncological treatment possible whenever there were no contraindications for the adjuvant treatment.