Chronic Myelomonocytic Leukemia in the Southern Cone, Argentina’s Experience

IABSTEBNER, MARCELO; BELLI, CAROLINA; ARBELBIDE, JORGE; SANTOS, I; NUCIFORA, ELSA; ENRICO, ALICIA; PINTOS, L; CELEBRIN, F; SAKAMOTO, FRANCICO; BENGIÓ, RAQUEL

Edimburgo

Simposio; 11th International Symposium on Myelodysplastic Syndromes (MDS); 2011

Background: WHO classification considers Chronic Myelomonocytic Leukemia (CMML) as a myeloproliferative/myelodysplastic disorder, and defines CMML I and CMML II according to medullary and peripheral blast count. Little is known about the clinical features of this heterogeneous disease in this region. Material and Methods: Between January 1985 and January 2011, CMML patients, diagnosed at different institutions in Argentina, were reported and registered. Morphological diagnosis was made according to FAB and WHO classifications. Cytogenetic analyses, BCR/ABL and JAK 2 mutations studies were carried out. Co-morbidities, CMML treatment, survival and leukemic progression were assessed during follow-up.  Results: Through a 26-year period study, we evaluated 98 patients, 35 female and 63 male (gender ratio 1.8), median age 72 (R 17–95), and myeloproliferative-CMML 23 patients (MP-CMML - more than 13000/mm3 leucocytes). There were 74 CMML patients type I and 17 type II. We analyzed 80 cytogenetic studies: high (7), intermediate (15) and low risk (58). Median survival of high + intermediate and low risk was of 26 and 31 months respectively. BCR/ABL and JAK 2 mutations were negative. Autoimmune manifestations (AIMs) were described in 26% of evaluable patients, and 67% of them, died. Patients with Hemoglobin <10 g/dl and platelets < 100000/mm3 were associated with a median survival of 25 and 24 months respectively. Fifty-six percent of the patients showed abnormal LDH. CMML treatment was: growth factors (37%), hydroxiurea and others chemotherapy (25%), and hypomethylation (17%). During follow up (median 20, range 0 – 105 months), 20 patients underwent AML and 37 died, including those patients who had undergone AML. We registered the following causes of death: co-morbidities (22%), infections (47%), hemorrhage (9%) and AML or disease progression (22%). Conclusion: CMML was a disorder diagnosed in older population, with predominance of male, Type I CMML and non-proliferative disease. Intermediate and high risk cytogenetic findings, Hemoglobin <10 g/dl, and platelet <100000/mm3 showed a significant short survival.