P17.72ACUTE LYMPHOBLASTIC LEUKEMIA AFTER TEMOZOLOMIDE TREATMENT FOR OLIGODENDROGLIOMA: CASE REPORT

INTRODUCTION: Temozolomide is an alkylating agent used in the treatment of high grade gliomas. The drug acts blocking cell division so tumor growth is slowed. TMZ has been reported to cause secondary myelodysplastic syndrome and acute myeloid leukemia while TMZ related acute lymphoblastic leukemia (ALL) is rare. We describe a man affected by a oligodendroglioma, who developed a T-cell acute lymphoblastic leukemia 12 months after stopping TMZ. CASE REPORT: A 41-years-old male presented a new-onset generalized seizure. A CT brain scan showed a bilateral frontal lesion and calcifications within. MRI documented a small contrast-enhancement in the left frontal region. The patient underwent surgical treatment. Histological examination revealed a oligodendroglioma (WHO grade II, 13% proliferation index). The molecular study identified a 1p/19q codeletion. The patient was treated with adiuvant chemotherapy (TMZ 200 mg/m2/day for 5 days in a 28- day-cycle). He was given a total of 36 cycles, ended in October 2012. Antiepileptic therapy was associated, then stopped after about three years, because he was seizures-free. During the three years of chemotherapy the disease remain stable. In conjunction with the 36th cycle the MRI perfusion and spettroscopy demonstrated a small tumor's recurrence in the left frontal region that was treated with gamma-knife radio surgery (total dose 20 Gy). The procedure was well tolerated and after three months the brain MRI was improved. The following neuroradiological examinations showed a stable disease. 12 months from the last TMZ-cycle submandibular and inguinal lymphadenopathy were discovered and the presence of a small ulcerated lesion with blood contours in the left peritonsillar side was observed. The patient underwent to Haematologist and after additional blood tests, T-cell acute lymphoblastic leukemia was diagnosed. The immunocytometric analysis on bone marrow cells showed the following phenotype: CD7++; CD8++, CD10 high, TdT++, CD38++. Cytogenetics analysis resulted in a normal karyotype. CT thoracic-abdominal scan showed diffuse lymphoadenophaties. The patients was treated with the protocol for lymphoblastic leukaemia running in out institution, with idarubicin, vincristine, cyclophosphamide, l-asparaginase and steroids. He obtained complete remission and he is now under treatment with cycles of consolidation chemotherapy. CONCLUSION: This is the first case described of T-cell acute lymphoblastic leukemia following TMZ therapy. TMZ is largely used for treatment of gliomas. The possibility that a therapy-related leukemia may develop must be taken in account in patients with haematological signs. Although the phenotype of this T-cell leukaemia is different from the other reported cases (until now only B-cell), the temporal relation between TMZ therapy and the diagnosis of leukaemia strongly suggests the causality between these two events.