The association between Good's syndrome (hypogammaglobulinemia and thymoma) l timoma suele asociarse a otras entidades, comúnmente llamadas síndromes paratími-cos. La más frecuente es la asociación con miastenia gravis (15%). La asociación con aplasia pura de la serie roja (APSR) es 5-10% y con inmunodeficiencia, denominada síndrome de Good (SG), alrededor de 5%. Por otro lado, 50% de las APSR se relacionan con timoma y el SG representa sólo 0,2% de todas las inmunodeficiencias 1-3 .El SG fue descrito por primera vez por el Dr. Robert Good en 1954, y se caracteriza por hipogammaglobulinemia y linfocitos B muy disminuidos en pacientes con timoma. También existe una relación de linfocitos T, CD4/CD8 invertida. Estos pacientes tienen una elevada susceptibilidad a infecciones bacterianas, virales, micóticas e infecciones oportunistas, y la resección del tumor en general no mejora la inmunodeficiencia 4 . No se conoce la causa de esta asociación 5 .La APSR también es extremadamente infrecuente. Se caracteriza por anemia severa normocítica, normocrómica, arregenerativa y ausencia absoluta de eritroblastos en la médula ósea, con normalidad de las otras series hematopoyéticas.La forma adquirida en adultos frecuentemente es de evolución crónica. La etiología es autoinmune y se han descrito varios mecanismos, como anticuerpos contra eritroblastos o contra eritropoyetina. También se ha propuesto la inhibición de las colonias eritroides de la médula ósea, mediada por linfocitos T o natural killer [6][7][8][9] . La APSR se ha asociado a infecciones virales, desórdenes autoinmune y neoplasias, siendo lo más frecuente la asociación con timoma.Sin embargo, la asociación de SG y APSR es extremadamente rara, y sólo existen alrededor de 16 casos publicados en la literatura.Se describe el caso de un varón que presentó la asociación de estas dos raras enfermedades: síndrome de Good y aplasia pura de la serie roja. Caso clínicoVarón de 70 años, con antecedentes de extirpación de timoma tipo linfocítico (tipo B1), el año 2000. Posteriormente, cursó con múltiples infecciones respiratorias altas y bajas, manejadas

PURPOSE Diffuse large B-cell lymphoma (DLBCL) is the most common lymphoma subtype. The purpose of this study was to evaluate the clinical features, prognostic factors, and results of DLBCL that was treated in the cancer centers of the public health system in Chile and compare cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) with rituximab with cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP). PATIENTS AND METHODS Patients age > 15 years who were treated in 18 cancer centers in the country between 2001 and 2017 were included. The Kaplan-Meier method was used to calculate overall survival (OS), and Cox proportional hazard regression modeling was used to evaluate the effect of the addition of rituximab to CHOP on OS. RESULTS A total of 1,807 patients were evaluated. The median age at diagnosis was 62 (range, 15-95) years, with a female predominance (53%). Half of the patients were age ≥ 60 years. Serology for HIV infection was positive in 5% of cases (96 cases). International Prognostic Index scores were available for 90% of patients, of which 45% had low-risk, 25% low-intermediate-risk, 18% high-intermediate-risk, and 11% high-risk scores. CHOP was administered to 986 patients (55%; median follow-up, 13.2 years) and R-CHOP to 821 patients (45%; median follow-up, 8.4 years). R-CHOP was associated with superior OS compared with CHOP (5-year 66% v 48%, and 10-year 53% v 35%; P < .001). CONCLUSION Rituximab improved the survival of patients with DLBCL diagnosed and treated in Chile. The benefit was sustained over time, with curative rates of > 50%. This intervention shows that the inclusion of this biological drug justified the expenses incurred by the Ministry of Health in the National Lymphoma Protocols in 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 Myelofibrosis (MF). The diagnosis includes clinical, histological and molecular features. There are not data from Chile. The aim of this study is to determinate epidemiological, clinical, diagnostic and therapeutic characteristics of Ph-MPN in our country. Methods: Descriptive and retrospective study. We reviewed the database of the Molecular Biology Laboratory at the Hospital del Salvador, a national reference laboratory, from 2012 to 2017. All patients referred as Ph-MPN were included. We reviewed the clinical records to obtain clinical information. Results: Clinical data was obtained from 468 cases from 12 public hospitals in Chile. Median age at diagnosis was 70 years. Female to Male ratio= 1,15:1, without significant differences between Ph-MPNs. ET was the most frequently Ph-MNP found, accounting for 49,4% of all Ph-MPN, followed by PV (37%) and MF (10,4%). A 66,2% of ET was JAK2 V617F+. Bone marrow biopsy was performed in 35% of ET cases. Only 7,8% had cytogenetic study. Splenomegaly was found in 8%. Thrombosis was observed in 23,8%. The median platelet count was 842x109/L. All patients received hydrea +/- aspirin or oral anticoagulation. Of the total of PV, 86,6% was JAK2+. Bone marrow biopsy was performed in a quarter of the cases. Thrombosis frequency was 14,5%. A 29% had splenomegaly. Median hemoglobin level was 18 gr/dl. All patients were treated with aspirin +/- phlebotomy and about half of them required cytoreduction. Two patients were refractory to hydrea and used ruxolitinib as second line treatment. A 63,3% of the MF were JAK-2+. Bone marrow biopsy was performed in 59% and 20% had a cytogenetic study. Only one fifth of patients had LDH measurement at diagnosis. Splenomegaly was observed in 75,5% of cases. Thrombosis frequency was 13%. Anemia was the most frequent finding in complete blood count. The treatments were heterogeneous, including hydrea, EPO, thalidomide/prednisone, danazol and ruxolitinib. Discussion: TE was the most common Ph-MPN. The epidemiological and blood count findings were similar to the data reported in the literature. It is important to note that with the 2016 WHO classification new criteria, some of patients diagnosed with ET, now will be in PV cathegory (21 patients in our serie). The distribution of JAK2V617F+ in Ph-MPN was similar to the published data, except for PV, in which we found a lower percentage of JAK2+. Thrombosis were lower than the data reported for PV. It is worrisome that bone marrow biopsy and cytogenetic study were performed only in a low percentage of the patients. The treatment strategies were heterogeneous and not standardized among the participating centers. These findings reveal a lack in the use of the diagnostic tools for Ph-MPN. It is important to improve clinical and molecular characterization of these patients in order to guide available therapeutic alternatives in our country. Disclosures No relevant conflicts of interest to declare.

Clinical and epidemiological characteristics of the Philadelphia negative myeloproliferative neoplasms in ChileBackground: 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.