[Clinical experience of using brentuximab-vedotin as therapy in relapsed/refractory Hodgkin's lymphoma at Hospital Guillermo Grant Benavente, Concepción, Chile]. / Experiencia clínica de uso de Brentuximab-vedotin como terapia de linfoma de Hodgkin recaído o refractario en Hospital Guillermo Grant Benavente, Concepción, Chile.

INTRODUCTION: Hodgkin's lymphoma is a B-cell neoplasm with a good prognosis but a poor response to chemotherapy in refractory or relapsed cases. Brentuximab-vedotin is an anti-CD30 monoclonal antibody approved for use in these cases. This study aims to describe the clinical experience of patients treated with brentuximab-vedotin through expanded access modality. MATERIALS AND METHODS: A retrospective study on clinical information of patients diagnosed with refractory or relapsed Hodgkin's lymphoma treated with brentuximab-vedotin at the Regional Hospital of Concepción in the period 2015-2021. RESULTS: 7 patients were identified, 5/7 male, with a median age of 35 years (21-50). Five cases were mixed cellularity, and two were nodular sclerosis. Four were in stage II, 1/7 in stage III, and 3/7 in stage IV. The median number of previous treatment lines was 4 (3-5), and the relapse was post-transplantation in two cases. In 6/7 cases, brentuximab-vedotin was used as induction, and in one case, it was used as post-autologous bone marrow transplant maintenance. The administration was outpatient via a peripheral route with a median dose of 150 mg and ten cycles. In one case, dose adjustment was required due to toxicity. Three out of 6 patients achieved complete remission and underwent autologous stem cell transplantation. CONCLUSION: brentuximab-vedotin is an outpatient medication with low toxicity that can optimize the treatment of patients with relapsed-refractory Hodgkin's lymphoma.

[Clinical features of blastic plasmacytoid dendritic neoplasm in Chile: report of 10 cases]. / Características clínicas de neoplasia de células dendríticas plasmocitoides blásticas en Chile: reporte de 10 casos.

BACKGROUND: Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare malignant tumor with a dismal prognosis, with isolated case reports in Chile. The BPDCN can present skin and bone marrow compromise, and its diagnosis is frequently confused with other pathologies. This study aimed to evaluate the clinical and immunophenotypical features of BPDCN in the Chilean population. METHODS: We performed a retrospective study from 2013 to 2021 in clinical records of 2 public Chilean referral hospitals, including ten patients, 80% male, with a median age of 66 years (15-81). RESULTS: The most frequent initial referral diagnoses were T-cell lymphoma (4/10) and acute myeloblastic leukemia (3/10). Seven patients presented skin and bone marrow involvement; we found a lower frequency of adenopathies (5/10), splenomegaly (2/10), and hepatomegaly (2/10). The complete blood count revealed anemia and leukopenia, with blasts in 5/10. Nine patients received induction therapy. CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) was indicated in 8/10 cases with remission in 5/8, and 1 patient received HyerCVAD (cyclophosphamide, vincristine, doxorubicin and dexamethasone, methotrexate, cytarabine) and an allogeneic bone marrow transplant. The median survival was 10 months (95% CI 4.2-15.8 months) with 9/10 deaths. Relapse in the central nervous system was documented in 2 cases. CONCLUSIONS: Our study found that BPDCN, a rare pathology in the Chilean population, shows a similar clinical presentation compared to previous studies. It is susceptible to respond to initial systemic and intrathecal chemotherapy.

Flow cytometry-detected changes in megaloblastic anemia secondary to cobalamin deficiency.

Introduction: Megaloblastic anemias secondary to Vitamin B12 deficiency are a group of pathologies produced by defective nuclear DNA synthesis. Objective: To describe the maturation alterations found in hematopoietic precursors of the bone marrow in a series of patients with megaloblastic anemia. Methods: Were included patients attended at the Regional Hospital of Concepción with bone marrow samples sent for the study of cytopenia by flow cytometry whose final diagnosis was megaloblastic anemia. The immunophenotype was performed with CD45, CD34, CD117, HLA-DR, markers of neutrophil (CD13, CD11b, CD10, CD16) and/or erythroblast (CD105, CD71, CD36) maturation. Results: From the flow cytometry laboratory database, 8 patients with megaloblastic anemia were identified, and myelodysplastic syndromes (n=9) and normal or reactive bone marrow (n=10) were used as controls. 44% were men, with a median age of 58 years. Megaloblastic anemia was associated with a higher proportion of size and complexity of erythroid and myeloid progenitors compared to lymphocytes compared to controls. The total percentage of erythroblasts and the proportion of CD34+ myeloid cells associated with erythroid lineage was higher in megaloblastic anemia, associated with a maturation arrest in the CD105+ precursor stage (69% vs 19% and 23%, p<0.001). The heterogeneity of CD36 and CD71 in megaloblastic anemia was similar to myelodysplastic syndromes. Conclusions: Megaloblastic anemia produces a heterogeneous involvement of hematopoiesis, characterized by a greater size and cellular complexity of precursors of the neutrophil and erythroid series and a maturation arrest of the erythroblasts.

Introducción: Anemias megaloblásticas secundarias a la deficiencia de vitamina B12 son patologías producidas por una síntesis defectuosa del ADN nuclear. Objetivo: Describir las alteraciones madurativas encontradas en precursores hematopoyéticos de la médula ósea de una serie de pacientes con anemia megaloblástica. Métodos: Se incluyeron pacientes atendidos en el Hospital Regional de Concepción con muestras de médula ósea enviadas para estudio de citopenias por citometría de flujo cuyo diagnóstico fue anemia megaloblástica. El inmunofenotipo se realizó con CD45, CD34, CD117, HLA-DR, marcadores de maduración de serie de neutrófilo (CD13, CD11b, CD10, CD16) y/o eritroblasto (CD105, CD71, CD36). Resultados: Se identificaron 8 pacientes con anemia megaloblástica y como controles se utilizaron síndromes mielodisplásicos (n=9) y médula ósea normal o reactiva (n=10). El 44% eran hombres, con una mediana de edad de 58 años. La anemia megaloblástica se asoció con una mayor proporción de tamaño y complejidad de progenitores eritroides y mieloides con respecto de los linfocitos en comparación a los controles. El porcentaje total de eritroblastos y la proporción de células mieloides CD34+ comprometidas con el linaje eritroide fue mayor en anemia megaloblástica, asociado a una parada madurativa en la etapa de precursor CD105+ (69% vs 19% y 23%, p <0.001). La heterogeneidad de CD36 y CD71 en anemia megaloblástica fue similar a los síndromes mielodisplásicos. Conclusiones: la anemia megaloblástica produce una afectación heterogénea de la hematopoyesis, caracterizada por un mayor tamaño y complejidad celulares de precursores de la serie neutrófilo y eritroide y una detención madurativa de los eritroblastos.

Flow cytometry-detected changes in megaloblastic anemia secondary to cobalamin deficiency

Introduction: Megaloblastic anemias secondary to Vitamin B12 deficiency are a group of pathologies produced by defective nuclear DNA synthesis. Objective: To describe the maturation alterations found in hematopoietic precursors of the bone marrow in a series of patients with megaloblastic anemia. Methods: Were included patients attended at the Regional Hospital of Concepción with bone marrow samples sent for the study of cytopenia by flow cytometry whose final diagnosis was megaloblastic anemia. The immunophenotype was performed with CD45, CD34, CD117, HLA-DR, markers of neutrophil (CD13, CD11b, CD10, CD16) and/or erythroblast (CD105, CD71, CD36) maturation. Results: From the flow cytometry laboratory database, 8 patients with megaloblastic anemia were identified, and myelodysplastic syndromes (n=9) and normal or reactive bone marrow (n=10) were used as controls. 44% were men, with a median age of 58 years. Megaloblastic anemia was associated with a higher proportion of size and complexity of erythroid and myeloid progenitors compared to lymphocytes compared to controls. The total percentage of erythroblasts and the proportion of CD34+ myeloid cells associated with erythroid lineage was higher in megaloblastic anemia, associated with a maturation arrest in the CD105+ precursor stage (69% vs 19% and 23%, p<0.001). The heterogeneity of CD36 and CD71 in megaloblastic anemia was similar to myelodysplastic syndromes. Conclusions: Megaloblastic anemia produces a heterogeneous involvement of hematopoiesis, characterized by a greater size and cellular complexity of precursors of the neutrophil and erythroid series and a maturation arrest of the erythroblasts.

Introducción: Anemias megaloblásticas secundarias a la deficiencia de vitamina B12 son patologías producidas por una síntesis defectuosa del ADN nuclear. Objetivo: Describir las alteraciones madurativas encontradas en precursores hematopoyéticos de la médula ósea de una serie de pacientes con anemia megaloblástica. Métodos: Se incluyeron pacientes atendidos en el Hospital Regional de Concepción con muestras de médula ósea enviadas para estudio de citopenias por citometría de flujo cuyo diagnóstico fue anemia megaloblástica. El inmunofenotipo se realizó con CD45, CD34, CD117, HLA-DR, marcadores de maduración de serie de neutrófilo (CD13, CD11b, CD10, CD16) y/o eritroblasto (CD105, CD71, CD36). Resultados: Se identificaron 8 pacientes con anemia megaloblástica y como controles se utilizaron síndromes mielodisplásicos (n=9) y médula ósea normal o reactiva (n=10). El 44% eran hombres, con una mediana de edad de 58 años. La anemia megaloblástica se asoció con una mayor proporción de tamaño y complejidad de progenitores eritroides y mieloides con respecto de los linfocitos en comparación a los controles. El porcentaje total de eritroblastos y la proporción de células mieloides CD34+ comprometidas con el linaje eritroide fue mayor en anemia megaloblástica, asociado a una parada madurativa en la etapa de precursor CD105+ (69% vs 19% y 23%, p <0.001). La heterogeneidad de CD36 y CD71 en anemia megaloblástica fue similar a los síndromes mielodisplásicos. Conclusiones: la anemia megaloblástica produce una afectación heterogénea de la hematopoyesis, caracterizada por un mayor tamaño y complejidad celulares de precursores de la serie neutrófilo y eritroide y una detención madurativa de los eritroblastos.

Experiencia clínica de uso de Brentuximab-vedotin como terapia de linfoma de Hodgkin recaído o refractario en Hospital Guillermo Grant Benavente, Concepción, Chile / Clinical experience of using brentuximab-vedotin as therapy in relapsed/refractory Hodgkin's lymphoma at Hospital Guillermo Grant Benavente, Concepción, Chile

INTRODUCCIÓN: El linfoma de Hodgkin es una neoplasia de células B de buen pronóstico, pero con mala respuesta a quimioterapia en casos refractarios o recaídas. Brentuximab vedotin es un anticuerpo monoclonal antiCD30 aprobado para su uso en estos casos. El presente trabajo tiene como objetivo describir la experiencia clínica de los pacientes tratados con brentuximab vedotin bajo la modalidad de acceso expandido. MATERIAL Y MÉTODOS: Estudio retrospectivo sobre información clínica de pacientes diagnosticados de linfoma de Hodgkin refractario o en recaída y tratados con brentuximab-vedotin en el Hospital Regional de Concepción en el período 2015-2021. RESULTADOS: Se identificaron 7 pacientes, 5/7 de sexo masculino, con una mediana de edad de 35 años (21-50). Cinco casos fueron celularidad mixta y 2 esclerosis nodular. Cuatro estaban en etapa II, 1/7 en etapa III y 3/7 en etapa IV. La mediana de líneas de tratamiento previas fue 4 (3-5) y en 2 casos la recaída fue postrasplante. En 6/7 casos se empleó como inducción y en un caso se empleó como mantención postransplante autólogo de médula ósea. La administración fue ambulatoria por vía periférica con una mediana de dosis 150 mg y 10 ciclos. En un caso se necesitó ajuste de dosis por toxicidad. Tres de 6 pacientes lograron remisión completa y fueron a trasplante autólogo de médula ósea. CONCLUSIONES: brentuximab vedotin es un medicamento ambulatorio de baja toxicidad que puede optimizar el tratamiento de pacientes con linfoma de Hodgkin recaído-refractario.

INTRODUCTION: Hodgkin's lymphoma is a B-cell neoplasm with a good prognosis but a poor response to chemotherapy in refractory or relapsed cases. Brentuximab-vedotin is an anti-CD30 monoclonal antibody approved for use in these cases. This study aims to describe the clinical experience of patients treated with brentuximab-vedotin through expanded access modality. MATERIALS AND METHODS: A retrospective study on clinical information of patients diagnosed with refractory or relapsed Hodgkin's lymphoma treated with brentuximab-vedotin at the Regional Hospital of Concepción in the period 2015-2021. RESULTS: 7 patients were identified, 5/7 male, with a median age of 35 years (21-50). Five cases were mixed cellularity, and two were nodular sclerosis. Four were in stage II, 1/7 in stage III, and 3/7 in stage IV. The median number of previous treatment lines was 4 (3-5), and the relapse was post-transplantation in two cases. In 6/7 cases, brentuximab-vedotin was used as induction, and in one case, it was used as post-autologous bone marrow transplant maintenance. The administration was outpatient via a peripheral route with a median dose of 150 mg and ten cycles. In one case, dose adjustment was required due to toxicity. Three out of 6 patients achieved complete remission and underwent autologous stem cell transplantation. CONCLUSION: brentuximab-vedotin is an outpatient medication with low toxicity that can optimize the treatment of patients with relapsed-refractory Hodgkin's lymphoma.

Características clínicas de neoplasia de células dendríticas plasmocitoides blásticas en Chile: reporte de 10 casos

Introducción: La neoplasia de células dendríticas plasmocitoides blásticas (NCDPB) es una hemopatía maligna poco frecuente y de mal pronóstico, con reportes de casos aislados en la realidad nacional. Produce compromiso cutáneo y de médula ósea y frecuentemente es confundida con otras patologías al diagnóstico. El presente trabajo tiene como objetivo describir las características clínicas de 10 pacientes diagnosticados en centros asistenciales chilenos. Material y Métodos: Se obtuvo en forma retrospectiva información clínica e inmunofenotípica de pacientes diagnosticados de NCDPB en los centros participantes en el periodo 2013-2021. Resultados: Se identificaron 10 pacientes, el 80% de sexo masculino, con una mediana de edad de 66 años (15-81). Los diagnósticos iniciales de derivación más frecuentes fueron linfoma T (4/10) y leucemia aguda mieloblástica (3/10). La mayoría presentó afección cutánea (7/10) y compromiso de médula (7/10) y en menor frecuencia adenopatías, esplenomegalia y hepatomegalia. En el hemograma se observó anemia y leucopenia, con blastos en frotis en 5/10. Se indicó CHOP en 8/10 casos con remisión en 5/8 y en un caso HyperCVAD seguido de trasplante alogénico de médula ósea. La mediana de sobrevida fue de 10 meses (IC 95% 4,2-15,8 meses) con 9/10 fallecidos. Se documentó recaída en sistema nervioso central en 2 casos. Conclusiones: La NCDPB es una patología poco frecuente que se presenta en la realidad nacional de forma similar a lo descrito en la literatura. Es susceptible de responder a quimioterapia inicial asociada a terapia intratecal.

Background: Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare malignant tumor with a dismal prognosis, with isolated case reports in Chile. The BPDCN can present skin and bone marrow compromise, and its diagnosis is frequently confused with other pathologies. This study aimed to evaluate the clinical and immunophenotypical features of BPDCN in the Chilean population. Methods: We performed a retrospective study from 2013 to 2021 in clinical records of 2 public Chilean referral hospitals, including ten patients, 80% male, with a median age of 66 years (15-81). Results: The most frequent initial referral diagnoses were T-cell lymphoma (4/10) and acute myeloblastic leukemia (3/10). Seven patients presented skin and bone marrow involvement; we found a lower frequency of adenopathies (5/10), splenomegaly (2/10), and hepatomegaly (2/10). The complete blood count revealed anemia and leukopenia, with blasts in 5/10. Nine patients received induction therapy. CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) was indicated in 8/10 cases with remission in 5/8, and 1 patient received HyerCVAD (cyclophosphamide, vincristine, doxorubicin and dexamethasone, methotrexate, cytarabine) and an allogeneic bone marrow transplant. The median survival was 10 months (95% CI 4.2-15.8 months) with 9/10 deaths. Relapse in the central nervous system was documented in 2 cases. Conclusions: Our study found that BPDCN, a rare pathology in the Chilean population, shows a similar clinical presentation compared to previous studies. It is susceptible to respond to initial systemic and intrathecal chemotherapy.