P17.02 * THE CORRELATION BETWEEN RESULTS OF COMPLEX TREATMENT AND 1P/19Q DELETION FOR PATIENTS WITH ANAPLASTIC OLIGODENDROGLIAL TUMORS

Abstract

INTRODUCTION: Anaplastic oligodendrogliomas and anaplastic oligoastrocytomas histologically are considered as grade III tumors. Both these forms are highly sensitive to chemotherapy and tend to have similar responses to complex postoperative therapy. Individual sensitivity to chemotherapy of anaplastic oligodendroglial tumors is of high importance, especially if 1p/19q co- deleted. AIM: A retrospective correlative research designed to evaluate the efficiency of complex radiotherapy and chemotherapy in patients with anaplastic oligodendroglial tumors depending on presence of combined 1p/19q loss. METHODS: Patients were eligible with diagnosed anaplastic oligodendrogliomas and anaplastic oligoastrocytomas between 2005 and 2010. 30 patients were included. Identification of combined 1p/19q loss was performed on paraffin-embedded histological material. All 30 patients underwent complex therapy: extent of surgery was total or subtotal resection, next received fractionated radiotherapy 60 Gy and followed by 6 cycles standart Temozolomide (TMZ). Primary endpoints - progression free survival (PFS) and overall survival (OS) were determined in each group respectively. RESULTS: 21 patient with anaplastic oligodendroglioma or anaplastic oligoastrocytoma were diagnosed with 1p/19q loss. Median PFS in this group reached 54.6 months, median OS - 67.7 months. The second group includes 9 patients without 1p/19q loss, with median PFS 43.3 months, median OS - 54.3 months. CONCLUSIONS: Median PFS and OS tend to be higher in patients with combined 1p/19q loss, but there is seen very high PFS and OS results in individual patients without 1p/19q loss.