Características clínicas y epidemiológicas de las neoplasias mieloproliferativas Philadelphia negativas en el sistema público de salud de Chile

Background: Philadelphia-negative myeloproliferative neoplasms (Ph-MPN) are chronic hematological disorders characterized by the overproduction of one or more mature myeloid blood cell lineages. Classical Ph-MPN are polycythemia vera (PV), essential thrombocytopenia (ET) and primary myelofibrosis (PMF). Aim: To assess the epidemiological, clinical and diagnostic characteristics of Ph-MPN in Chile. Material and Methods: Retrospective review of medical records of all patients referred as MPN from 2012 to 2017. Patients with (9;21) translocation were excluded. Results: Data of 462 cases with a median age of 69 years from 10 public hospitals was reviewed. ET was the most frequently Ph-MNP found. The incidence of Ph-MPN was 1.5 x 100.000 cases. The JAK2 V617F mutation study was performed in 96% of patients and only 30% had a bone marrow biopsy. Thrombotic events were observed in 29% of patients. Bleeding events were observed in 7%. Five-year overall survival was 87%. Conclusions: ET is the most frequent Ph-MPN. The mean incidence was lower than reported in the literature, in part because of a sub diagnosis.

Mieloma múltiple en Chile: Respuesta a tratamiento en pacientes con mieloma múltiple elegibles para trasplante autólogo de progenitores hematopoyéticos / Response rates to first-line treatment in eligible patients to autologous stem transplantation in Chile

Background The treatment of choice of newly diagnosed multiple myeloma (NDMM) is an induction with proteasome inhibitors followed autologous stem cell transplantation (HSCT). Since 2013, the treatment of these patients in the public system is based on CTD (cyclophosphamide, thalidomide, and dexamethasone). Aim To evaluate the response rates achieved with CTD, and the results of HSCT in patients with NDMM in the public setting. Material and Methods Data from patients considered as candidates for HSCT from different centers of the National Adult Antineoplastic Drug Program (PANDA, for its acronym in Spanish), diagnosed between 2013 and 2017, was analyzed. The response to treatment of first and second lines of treatment was evaluated, in addition to the results of HSCT. An optimal Response was defined as the sum of strict complete remission, complete remission and very good partial response (sCR, CR and VGPR). Results One hundred and seventy-seven patients were analyzed, 54% women, and 53% with IgG multiple myeloma. Information about the international staging system was retrieved in 127 patients (71%). Seventeen percent were ISS I, 22% in ISS II and 32% ISS III. CTD was used as first treatment in 106 patients (60%), and cyclophosphamide, bortezomib and dexamethasone (CyBorD) in 13 (7%). As first line, CTD had an overall response of 50.9%, and CyBorD of 76.9%. Thirty patients were treated with bortezomib as second line treatment. Forty patients (22%) underwent HSCT. The 5-year Overall Survival (OS) in transplanted patients and non-transplanted patients was 100 and 62% respectively (p < 0.01). Conclusions The response rate achieved by CTD in these patients is suboptimal. The response to CyBorD was better.

Leucemia de células plasmáticas primaria: experiencia en un hospital público chileno / Primary plasma cell leukemia: report of five cases

Background: Primary plasma cell leukemia (pPCL) is uncommon, aggressive and has a different biology than multiple myeloma (MM). Aim: To report the features of patients with pPCL. Material and Methods: Review of databases of the Hematology Department and the Hematology laboratory. Results: Of 178 patients with monoclonal gammopathies, five (2.8%) patients aged 33 to 64 years (three females) had a pPCL. The mean hemoglobin was 7.3 g/dL, the mean white blood cell count was 52,500/mm3, with 58% plasma cells, and the mean platelet count was 83,600/mm3. The mean bone marrow infiltration was 89%, LDH was 2,003 IU/L, serum calcium was 13 mg/dL, and creatinine 1.5 mg/dL. Two patients had bone lesions. Three were IgG, one IgA lambda and one lambda light chain. CD20 was positive in one, CD56 was negative in all and CD117 was negative in 3 cases. By conventional cytogenetic analysis, two had a complex karyotype. By Fluorescence in situ Hybridization, one was positive for TP53 and another for t (11; 14). One patient did not receive any treatment, three patients received VTD PACE and one CTD. None underwent transplant. Three patients are alive. The mean survival was 14 months. Conclusions: These patients with pPCL were younger and had a more aggressive clinical outcome than in multiple myeloma.

Aplasia medular adquirida, experiencia en un hospital público de referencia / Acquired aplastic anemia: experience in a public hospital

Background: The first line treatment for patients < 40 years old with aplastic anemia (AA) is allogeneic HLA-identical sibling donor transplantation (SCT). Immunosuppressive therapy (IST) with a combination of Thymoglobuline (ATG) and cyclosporine is used for older patients or those without a donor. Five year overall survival (OS) for both therapies is > 70%. Aim: To report the experience with SCT and ATG for AA in a public hospital. Patients and Methods: AA was diagnosed in 42 patients between 1998 and 2016, according to Camitta criteria. Thirty eight (90%) received treatment, 7 (18%) under 40 years old received SCT, and 31 (82%) IST. The rest were not treated. OS was calculated from date of diagnosis until last control, death or loss from follow up. Results: Complete or partial hematologic response, was obtained in 71% and 58% of cases with SCT and IS, respectively. Five year OS was 71% and 55% with SCT and IST, respectively. No difference in response was observed between horse and rabbit ATG. Conclusions: SCT from an HLA-identical sibling donor had a high response rate and survival. IST instead, had a lower response and survival, due to an initial high mortality rate.

Síndrome neuroléptico maligno en relación al uso de clozapina / Neuroleptic malignant syndrome in relation to the use of clozapine

Se presenta el caso de un varón de 37 años, esquizofrénico en tratamiento con Clozapina. Es hospitalizado por neurotropenia severa y brusca, evolucionando rápidamente con compromiso de conciencia, agitación psicomotora, temperatura alta e hipotensión refractaria a aporte de volumen. Manejado en la Unidad de Cuidados Intensivos, se asiste a complicaciones renales y respiratorias, destacando la gran hipertonía muscular generalizada. Finalmente, el paciente fallece por paro cardio-respiratorio en asistolía. Se analiza el cuadro de hipertermia y se le relaciona con el uso de neurolépticos, describiéndose la toxicidad por clozapina, que produce neutropenia. Se plantea el diagnóstico diferencial entre el síndrome neuroléptico maligno, la hipertermia maligna y el síndrome serotoninérgico. Por último, se describe el manejo médico de la hipertermia.