Tumors of the Pineal Region: Principles of Treatment

A.N. Konovalov, D.I. Pitskhelauri, N.N. Bragina, N.K. Serova, A.G. Melikyan, G.L. Kobzyakov, A.G. Korshunov, N.V. Arutyunov, O.S. Zaitsev, S.A. Raevskaya, I.A. Voroninf, V.N. Azizyan, A.S. Dzeitova

(Burdenko Research Institute of Neurosurgery, Moscow)

Tumors of the pineal region and posterior segments of the third ventricle are rare and deep-lying masses with a rather diverse histological character. They account for 0.5-1% of all intracranial tumors, watched in European and American population; more than 2/3 of them are malignant.

There were more than 700 cases, examined and treated in the Burdenko Research Institute of Neurosurgery in 1976-2003. Operations were performed in 330 of them.

The goal of the present research was to analyze results of treatment of 287 cases with tumors, verified histologically. Stereotaxic biopsy failed give any information on a histological structure of a tumor in 5 cases.

A histological structure of tumors of the pineal region was as follows: germinal-cellular neoplasms 87 cases (31%), neoplasms of the pineal body parenchyma 75 (27%), glial neoplasms 77 (27%) and other neoplasms 44 (15%). There were 255 direct surgical intervention, made in 245 cases. As for the rest patients, histological diagnosis was verified with the help of stereotaxic biopsy.

Tumors of the pineal region were removed with use of occipital transtentorial and infratentorial supracerebellar approaches in 138 (54%) and 87 (34%) cases respectively. A subchoroidal approach, an approach via the forth ventricle and combined approaches were performed in the rest patients. Total removal was achieved in 148 cases (58%). It was subtotal and partial in 74 (29%) and 33 (13%) patients respectively.

Different shunting operations were made in 168 cases (58%). Radiotherapy, combined with surgical removal or used as an independent method, was carried out in 145 cases (51%). Chemotherapy was applied in 16 patients with malignant tumors of the pineal region. It was 10% of all malignant neoplasms of this localization.

Catamnestic data were obtained in 209 cases (80%). Their processing demonstrated survival of all the cases with benign tumors. As for germinomas, survival of 5 and 10 years was watched in 88% and 95% of cases respectively. The same indices in other neoplasms were as follows: malignant glial tumors 80% and 50%, malignant tumors of the pineal body parenchyma 44% and 0%, malignant germinal-cellular tumors 20% and 0%.

Thus, surgical removal is practically the only and most effective method of treatment of benign pineal tumors. Treatment of patients with malignant pineal tumors demands a combination of surgical removal with radio- and chemotherapy. Germinomas are very sensitive to radiotherapy and should be subject only to this type of treatment.