Teratomas of the central nervous system: treatment considerations based on 34 cases.

Object. The optimum clinical management of central nervous system (CNS) teratomas, particularly postsurgical adjuvant therapy, is still unclear, partly as a result of the tumors' low incidence. In this study the authors analyze 34 cases of CNS teratomas so that they may adequately indicate management of these lesions. Methods. The median age of the 34 patients was 13 years. Twenty-seven patients treated between 1970 and 1991 were retrospectively reviewed. Four of these 27 patients died as a result of radical surgery; each of them had a teratoma involving the hypothalamus. After initial treatment, which included radiation therapy, 20 patients (48%) had died. In all seven cases of mature teratomas there was no recurrence. In two cases of immature teratomas in which there was complete surgical resection there was recurrence; however, salvage therapies were effective. Seven of eight patients with highly malignant teratomas died; for these patients salvage therapies, including repeated radiation and chemotherapy, failed. Seven patients who presented with CNS teratomas between 1992 and 1996 received adjuvant chemotherapy and radiation therapy according to a prospective study protocol. All seven patients were free from recurrence with a 70 to 100% Karnofshy Performance Scale score at a median follow-up period of 41 months. Patients with CNS teratomas rarely responded completely to chemotherapy of radiation therapy; an effective adjuvant therapy produced a partial response at best. Conclusions. Because teratomas show various responses to adjuvant therapy, a misdiagnosis of their histological subtype will lead to inadequate therapy. A diverse therapeutic protocol based on histological diagnosis is necessary to plan appropriate management. Treatment recommendations are discussed in detail in the article.