Significado clínico y frecuencia de la alteración genético/molecular 11q23/MLL en lactantes con leucemia aguda en Chile / Clinical significance and frequency of the 11q23/MLL genetic/molecular alteration in chilean infants with acute leukemia

Background: Acute leukemia (AL) in infants generally shows distinctive biologic features and has a poor prognosis. Aim: To study the frequency of the cytogenetic alteration of11q23 chromosome or the recombination of MLL gene in infants less than 18 months old, with acute leukemia. Patients and methods: We analyzed 37 cases of AL in infants less than 18 months of age diagnosed in Chile from 1989 to 1999. The clinical features and cytogenetic/molecular defects of 11q23MLL gene rearrangement and their influence in prognosis were determined. Results: There were 18 cases of acute Lymphoblastic leukemia (ALL) characterized by female sex (67 per cent) high presenting leukocyte count (median 99 x109/L), blast cells with a CD10 negative phenotype (50 per cent) and 11q23/MLL rearrangement (39 per cent). Molecular abnormalities of 11q23 were significantly associated with adverse prognosis, with an event free survival (EFS) of only 14 ñ 12 per cent. Interestingly, infants with germ line 11q23 had a very good outcome with an EFS of 73 ñ 11 per cent (p<0.025). There were 19 cases of acute myeloblastic leukemia (AML) characterized by male sex (63 per cent) high leukocyte count (median 93 x 109/L), FAB-MS morphology (53 per cent) and 11q23/MLL rearrangement (53 per cent). EFS was very poor, 20 ñ 9 per cent and 33ñ4 per cent for rearranged and germinal group respectively (p=NS), due to a high mortality rate during the first month of diagnosis. Conclusions: These findings demonstrate that Chilean ALL infants with 11q23 abnormalities have a very poor prognosis. However those with germinal state can enjoy a prolonged disease free survival with the current treatment protocols

Leucemia mieloide aguda del adulto: resultado del protocolo nacional de drogas antineoplásica: Hospital del Salvador 1990-1998 / Acute myeloid leukemia in the adult: results of the national antineoplastic drug protocol (Panda) at Hospital del Salvador, Chile

Background: The incidence of acute myeloid leukemia is 3 cases per 100.000 inhabitants/year and its five years event free survival is 15 to 20 percent. Since the incorporation of trans retinoic acid, event free survival of M3 acute myeloid leukemia is 80 percent. Aim: To report the results of acute myeloid leukemia treatment at the Hospital del Salvador, between 1990 and 1998. Patients and methods: The medical records of 117 patients (66 female, mean age 48.2 years), treated between 1990 and 1998 using PANDA protocol, were retrospectively reviewed. Immunophenotyping was done in 69 patients and cytogenetic studies were done in 65. Results: Sixteen percent of patients had M3 acute myeloid leukemia. The most frequent phenotype was the association of DR, CD34 plus a panmyeloid marker. DR and CD34 were negative in seven of nine patients with M3 acute myeloid leukemia. Cariotype was abnormal in 78 percent of patients. Complete remission was achieved in 65 percent of cases with a 13 percent of failures. Early mortality was 21.3 percent and decreased to 6.1 percent in the last three years. Infections and coagulation disorders were the main causes of death. Mean survival was 10.5 months. Five years event free survival was 11 percent. In M3 acute myeloid leukemia, the figure is 50 percent. Conclusions: Treatment results are less effective than protocols that consider more aggressive chemotherapeutic protocols or bone marrow transplantation. The reduction in early mortality is due to a better management of febrile neutropenia