Presence of EBV antigens detected by a sensitive method in pediatric and adult Diffuse Large B-cell lymphomas.

In 2017, the World Health Organization (WHO) confirmed a new entity, Epstein Barr virus (EBV) + Diffuse large B cell lymphoma (DLBCL), not otherwise specified (NOS). Traces of EBV transcripts were described in lymphomas, including DLBCL, that were diagnosed as EBV negative by conventional methods. The aim of this study was to detect viral genome by qPCR, as well as LMP1 and EBNA2 transcripts, with a more sensitive method in DLBCL cases from Argentina. Fourteen cases originally considered as EBV negative expressed LMP1 and/or EBNA2 transcripts. In addition, LMP1 and/or EBNA2 transcripts were also observed in bystander cells. However, EBERs+ cells cases by conventional ISH showed higher numbers of cells with LMP1 transcripts and LMP1 protein. In the cases that were EBERS- in tumor cells but with expression of LMP1 and/or EBNA2 transcripts, the viral load was below the limit of detection. This study provides further evidence that EBV could be detected in tumor cells by more sensitive methods. However, higher expression of the most important oncogenic protein, LMP1, as well as increased viral load, are only observed in cases with EBERs+ cells by conventional ISH, suggesting that traces of EBV might not display a key role in DLBCL pathogenesis.

Guía de inmunohistoquímica para técnicos / inmunohistochemist ry guide for technicians

La inmunohistoquímica (IHQ) es una técnica esencial y de uso rutinario en anatomía patológica. Contribuye en el diagnostico especifico de las enfermedades, en particular las neoplásicas; permite una adecuada clasificación en función de linaje u origen (tales como carcinoma, melanoma, linfoma, etc.); brinda información pronóstica y sus resultados, evaluados en el contexto clínico, contribuyen a la elección del tratamiento de los pacientes. Basada en la alta especificidad y afinidad de la reacción antígeno-anticuerpo la IHQ permite, mediante el empleo de anticuerpos específicos y sistemas de detección, determinar la expresión de biomarcadores (proteínas). Se puede realizar sobre tejidos en fresco, fijados en formol y coágulos citológicos incluidos en parafina, permitiendo la evaluación simultánea de la morfología. Es una técnica compleja, en la cual el resultado final está influenciado por múltiples parámetros de las fases preanalítica, analítica y post-analítica. Dependiendo de la selección y el rendimiento de estos parámetros, el resultado final de la técnica utilizando el mismo anticuerpo primario puede mostrar un rango de negativo a positivo para el antígeno objetivo. Para que su empleo sea de máxima utilidad y los resultados obtenidos sean reproducibles y confiables es imprescindible la estandarización de cada uno de los pasos o fases desde la obtención de la muestra, con la adecuada fijación de los tejidos, hasta el ajuste de la técnica, lectura y valorización de los resultados obtenidos a los criterios establecidos mediante controles de calidad internos y externos.

[ASIA syndrome: breast implant and Still's disease]. / Síndrome ASIA: Prótesis mamarias y enfermedad de Still.

Connective tissue diseases associated with silicone breast implants have been widely discussed. In the last decade, siliconosis has been included in the autoimmune/inflammatory syndrome induced by adjuvants (ASIA) next to Gulf War syndrome, macrophage myofascitis and postvaccination phenomena. The ASIA syndrome may appear as lupus, rheumatoid arthritis, or more rarely, as adult Still's disease. We discuss the case of a patient with prolonged fever and clinical criteria for ASIA and Still's disease. The prostheses were resected and pathology showed absence of breast implant associated anaplastic lymphoma ALK (-). Physicians should be alert to these new entities linked to silicone breast implants.

[AIDS related lymphomas: Histopathological subtypes and association with Epstein Barr virus and Human Herpes virus type-8]. / Linfomas asociados con la infección por el virus de la inmunodeficiencia humana: subtipos histológicos y asociación con los virus de Epstein Barr y Herpes-8.

Non-Hodgkin lymphomas (NHL) of the B-cell type are the second most common neoplasm among patients with human immunodeficiency virus (HIV) infection and AIDS. Here, we evaluated 48 cases of AIDS-related lymphomas (ARL) diagnosed at the Histopathological Division of the Instituto de Investigaciones Hematológicas of the National Academy of Medicine. Five were females and 43 were males with a median of age of 37 years at the time of the diagnosis. Micrometer sections were prepared and stained with hematoxilin-eosin; immunohistochemical examination for the presence of Epstein-Barr virus (EBV) was carried out in 48/48 cases. Additionally, biotinilated oligonucleotides were used to determine the presence of DNA of the Human Herpes virus type-8 (HHV-8) in 14/14 biopsy smears corresponding to plasmablastic lymphomas (PL). All were fenotype B cell lymphomas with an aggressive course and advanced neoplasm disease at the time of diagnosis. Virological findings showed the strong association between EBV and AIDS-related NHL. According to the histopathological subtype, the EBV genome was detected in 16/21 (76%) diffuse large B cell lymphomas, 1/3 Burkitt lymphoma and 3/4 (75%) of primary central nervous system lymphomas. Globally, EBV genome was detected in 20/28 NHL of this series. Detection of HHV-8 was negative in all cases of PL. Hodgkin lymphoma were more frequent in males 18/20 (90%), with an aggressive clinical course and a significant predominance of the subtypes associated with worse prognosis (90% of cases). We detected a significant association between EBV and HL (90% of cases). We consider that all cases of AIDS related lymphomas should be assessed for the presence of EBV because its presence may play a role in the prognosis.

Linfomas asociados con la infección por el virus de la inmunodeficiencia humana: subtipos histológicos y asociación con los virus de Epstein Barr y Herpes-8 / AIDS related lymphomas: Histopathological subtypes and association with Epstein Barr virus and Human Herpes virus type-8

Los linfomas no Hodgkin (LNH) constituyen la segunda neoplasia definitoria de Sida más frecuente. En el presente trabajo se evaluaron 48 casos de linfomas asociados con la enfermedad debida al virus de la inmunodeficiencia humana (HIV) diagnosticados en la División Histopatología del Instituto de Investigaciones Hematológicas de la Academia Nacional de Medicina. Se incluyeron en la investigación 5 mujeres y 43 hombres con una mediana de edad al momento del diagnóstico de la neoplasia de 37 años. La evaluación morfológica se realizó en cortes coloreados con hematoxilina-eosina, estudio inmunohistoquímico para la detección del virus de Epstein Barr (VEB) en 48/48 casos, y mediante sonda oligonucleotídica biotinilada para la detección del ADN del Herpes virus humano tipo-8 (HHV-8) en 14/14 linfomas plasmoblásticos (LP). Todos fueron linfomas de fenotipo B, con un curso clínico agresivo y enfermedad neoplásica avanzada al momento del diagnóstico. Se pudo demostrar la fuerte asociación del VEB con los linfomas asociados al sida, con frecuencias que variaron según el subtipo histológico: 16/21 (76%) para los linfomas difusos de grandes células; 1/3 casos (33%) de linfomas de Burkitt y 3/4 (75%) en los linfomas primarios del sistema nervioso central. Globalmente, el genoma del VEB se detectó en 20/28 (71%) de las muestras de biopsias de LNH de esta serie. La detección del HHV-8 resultó negativa en los 14 LP. Los linfomas de Hodgkin fueron más frecuentes en varones,18/20 (90%), con un curso clínico agresivo y franco predominio de los subtipos histológicos de peor pronóstico (90% de casos). En estas neoplasias también se comprobó una frecuente asociación patogénica con el VEB (90% de casos).

Non-Hodgkin lymphomas (NHL) of the B-cell type are the second most common neoplasm among patients with human immunodeficiency virus (HIV) infection and AIDS. Here, we evaluated 48 cases of AIDS-related lymphomas (ARL) diagnosed at the Histopathological Division of the Instituto de Investigaciones Hematológicas of the National Academy of Medicine. Five were females and 43 were males with a median of age of 37 years at the time of the diagnosis. Micrometer sections were prepared and stained with hematoxilin-eosin; immunohistochemical examination for the presence of Epstein-Barr virus (EBV) was carried out in 48/48 cases. Additionally, biotinilated oligonucleotides were used to determine the presence of DNA of the Human Herpes virus type-8 (HHV-8) in 14/14 biopsy smears corresponding to plasmablastic lymphomas (PL). All were fenotype B cell lymphomas with an aggressive course and advanced neoplasm disease at the time of diagnosis. Virological findings showed the strong association between EBV and AIDS-related NHL. According to the histopathological subtype, the EBV genome was detected in 16/21 (76%) diffuse large B cell lymphomas, 1/3 Burkitt lymphoma and 3/4 (75%) of primary central nervous system lymphomas. Globally, EBV genome was detected in 20/28 NHL of this series. Detection of HHV-8 was negative in all cases of PL. Hodgkin lymphoma were more frequent in males 18/20 (90%), with an aggressive clinical course and a significant predominance of the subtypes associated with worse prognosis (90% of cases). We detected a significant association between EBV and HL (90% of cases). We consider that all cases of AIDS related lymphomas should be assessed for the presence of EBV because its presence may play a role in the prognosis.

Unusual case of plasmablastic non-Hodgkin's lymphoma located in the liver. First case reported in an AIDS patient.

Plasmablastic lymphoma is a rare and a relatively new entity that was first described in the jaws and the oral cavity of HIV-AIDS patients. We report a case of plasmablastic lymphoma involving the liver in an AIDS patient. Plasmablastic lymphoma is considered a diffuse large B-cell lymphoma with a unique phenotype and predilection for the oral cavity. The case presented had a unique hepatic lesion, localized in the left lobe of the liver. Diagnosis was confirmed by hepatic biopsy guided by Computerized Tomography scan and histopathology. The smears showed a dense infiltrate composed by atypical lymphocytes with numerous plasmocytes expressing the plasma cell markers MUM-1 and CD138 and negative for the B-cell markers CD3, CD20 and CD45. Immunohistochemical and in situ hybridization revealed the Epstein-Barr virus genome in the atypical cells. Polymerase chain reaction was negative for HHV-8 RNA.

Invaginación ileocecal como forma de presentación de linfoma no Hodgkin en un paciente con SIDA / Ileocolic intussusception due to a large B cell lymphoma in a patient with AIDS

La invaginación intestinal es poco frecuente en el adulto. Aquí se describe el caso de un paciente adulto con SIDA que desarrolló una invaginación ileocólica secundaria a un linfoma de células B localizado en el ciego. Los hallazgos quirúrgicos fueron: íleon libre de tumor, invaginado en el ciego infiltrado por la neoplasia. Se realizó la resección del hemicolon derecho debido a la tumoración localizada en el ciego, causante de la invaginación. Se revisó la literatura inglesa y española sobre este tema.

Adult intussusception is rare. Here, we describe a case of an AIDS adult patient who developed an ileocolic intussusception secondary to a large B cell lymphoma of the cecum. Surgical findings included the ileon free of the tumor and invaginated within the cecum with infiltrating neoplasm. Surgical treatment included the resection of the right hemicolon because of the tumor, located in the cecum, causing intussusception. The english and spanish literature is reviewed.

Burkitt's lymphoma of the duodenum in a patient with AIDS

Non-Hodgkin's lymphoma of B-cell type is the second most common neoplasm after Kaposi's sarcoma, among patients with human immunodeficiency virus infection. Most non-Hodgkin's lymphoma cases that are associated with acquired immunodeficiency syndrome involve extranodal sites, especially the digestive tract and the central nervous system. We report a case of primary lymphoma of the duodenum in a patient with AIDS. Upper gastrointestinal endoscopy revealed pseudopolypoid masses found in the second portion of the duodenum. A complete diagnostic study including histological, immunohistochemical and virological analyses showed high-grade B-cell Burkitt's lymphoma. The Epstein-Barr virus genome was detected in biopsies by immunohistochemical and in situ hybridization.

O linfoma não-Hodgkin de células B é a segunda neoplasia mais comum em pacientes com infecção pelo vírus da imunodeficiência humana depois do sarcoma de Kaposi. A maioria dos casos de linfoma não-Hodgkin associados com a síndrome da imunodeficiência adquirida envolve locais extraganglionares, especialmente o trato digestivo e o sistema nervoso central. Nós relatamos um caso de linfoma primário do duodeno em um paciente com AIDS. Uma endoscopia digestiva alta mostrou massas pseudopolipóides encontradas na segunda porção do duodeno. Um estudo diagnóstico completo incluindo exames histológicos, imunohistoquímicos e virológicos mostrou um linfoma de células B tipo Burkitt. Detectou-se genoma do vírus Epstein-Barr em biópsias por hibridização in situ e imuno-histoquímica.

Linfomas del tubo digestivo y glándulas anexas en pacientes con SIDA: serie de casos / Non-Hodgkin's lymphomas of the digestive tract and anexal glands in AIDS patients

Introducción: el linfoma no Hodgkin (LNH) es la segunda neoplasia más frecuente en pacientes con SIDA. Una de las principales características de los LNH asociados con el SIDA es la alta frecuencia de compromiso extranodal, incluyendo el tracto astrointestinal, como manifestación inicial de la neoplasia. Métodos: se analizaron de manera retrospectiva las características epidemiológicas, clínicas, virológicas, inmunológicas e histopatológicas de 8 pacientes con diagnóstico de linfomas del tracto gastrointestinal y glándulas anexas (hígado y parótida) asistidos en la División de VIH- /SIDA del Hospital de Enfermedades Infecciosas F J Muñiz de Buenos Aires, Argentina, entre enero de 1997 y diciembre de 2004. Todos los pacientes fueron evaluados por tomografía computarizada y examen de la médula ósea, además de los exámenes endoscópicosde diagnóstico. Resultados: todos los pacientes fueron varones; 4 eran heterosexuales, 2 homosexuales, uno hemofílico y uno adicto a drogas endovenosas. Tres pacientes presentaron coinfección por el virus de la hepatitis C. La mediana de edad fue de 42 años y la mediana de linfocitos T CD4 + fue de 87 células/uL al momento del diagnóstico de la neoplasia. Ningún paciente recibía TARGA al momento del diagnóstico del linfoma. La incidencia global de linfomas (primarios del sistema nervioso central, no Hodgkin sistémicos y de Hodgkin) durante el período de estudio fue de 2,9% (54 casos); 17 pacientes (32%) tuvieron diagnóstico de LNH sistémicos; 10 (58,8%) de ellos tuvieron presentación extranodal al momento del inicio de las mani manifestaciones clínicas y 8 (80%) comprometieron el tubo digestivo y las glándulas anexas (parótida, cavum, esófago, estómago, duodeno, colon derecho en 2 casos e hígado en el restante), como LNH primarios, de alto grado y de fenotipo "B". Todos los pacientes presentaronsíntomas "B" al momento del diagnóstico. De acuerdo con los criterios de estadificación de Lugano, 4 se encontraban en el estadio...

Background: Non-Hodgkin's lymphoma (NHL) is the second most common neoplasm among patients with AIDS. One of the major clinical characteristics of AIDS-associated NHL is the high frequency of extranodal involvement, including the gastrointestinaltract, at initial presentation. Methods: From January 1997 to December 2004, 8 cases of NHL of the digestive tract and anexal glands (liver and parotid gland) were observed at the HIV/AIDS division of the Infectious Diseases F J Muñiz Hospital from Buenos Aires,Argentina. All patients were staged by computed tomography scanning and bone marrow examination, in addition to the endoscopic evaluation. Results: All patients were males; 4 were heterosexual, 2 homosexual, and 1 were a hemophilic and an intravenous drug abuser. The median age was 42 years and the median CD4 T cell count was 87 cells/uL at the time of the diagnosis of neoplasm. No patient was receiving highly active antiretroviral therapy (HAART) at lymphoma diagnosis. The global incidence of AIDS-associated lymphomas (central nervous system lymphomas, non-Hodgkin lymphomas and Hodgkin lymphoma) during the time of study was 2,9% (54 cases); 17 patients(32%) had diagnosis of systemic NHL; 10 (58,8%) of them were extranodal at the onset of clinical symptoms and 8 (80%) involvement the digestive tract and anexal glands (parotid gland, cavum, esophagus, stomach, duodenum, the right colon in 2 patients and the liver), as primary NHL of high grade and "B" phenotype. All patients presented "B" symptoms at the time of diagnosis. Primary duodenal lymphoma was the only Burkittlymphoma of this serie and we detected the Epstein-Barr virus genome in the biopsy smears of this tumor and in the hepatic lymphoma. Four patients were treated with systemic chemotherapy with granulocytic growth factor support plus highly active antiretroviral therapy (HAART); 2 of them (cavum and one of the colon) had a prolonged survival with immune reconstitution during 5 and 6...

Linfomas del tubo digestivo y glándulas anexas en pacientes con SIDA: serie de casos / Non-Hodgkins lymphomas of the digestive tract and anexal glands in AIDS patients

Introducción: el linfoma no Hodgkin (LNH) es la segunda neoplasia más frecuente en pacientes con SIDA. Una de las principales características de los LNH asociados con el SIDA es la alta frecuencia de compromiso extranodal, incluyendo el tracto astrointestinal, como manifestación inicial de la neoplasia. Métodos: se analizaron de manera retrospectiva las características epidemiológicas, clínicas, virológicas, inmunológicas e histopatológicas de 8 pacientes con diagnóstico de linfomas del tracto gastrointestinal y glándulas anexas (hígado y parótida) asistidos en la División de VIH- /SIDA del Hospital de Enfermedades Infecciosas F J Muñiz de Buenos Aires, Argentina, entre enero de 1997 y diciembre de 2004. Todos los pacientes fueron evaluados por tomografía computarizada y examen de la médula ósea, además de los exámenes endoscópicosde diagnóstico. Resultados: todos los pacientes fueron varones; 4 eran heterosexuales, 2 homosexuales, uno hemofílico y uno adicto a drogas endovenosas. Tres pacientes presentaron coinfección por el virus de la hepatitis C. La mediana de edad fue de 42 años y la mediana de linfocitos T CD4 + fue de 87 células/uL al momento del diagnóstico de la neoplasia. Ningún paciente recibía TARGA al momento del diagnóstico del linfoma. La incidencia global de linfomas (primarios del sistema nervioso central, no Hodgkin sistémicos y de Hodgkin) durante el período de estudio fue de 2,9% (54 casos); 17 pacientes (32%) tuvieron diagnóstico de LNH sistémicos; 10 (58,8%) de ellos tuvieron presentación extranodal al momento del inicio de las mani manifestaciones clínicas y 8 (80%) comprometieron el tubo digestivo y las glándulas anexas (parótida, cavum, esófago, estómago, duodeno, colon derecho en 2 casos e hígado en el restante), como LNH primarios, de alto grado y de fenotipo "B". Todos los pacientes presentaronsíntomas "B" al momento del diagnóstico. De acuerdo con los criterios de estadificación de Lugano, 4 se encontraban en el estadio...(AU)

Background: Non-Hodgkins lymphoma (NHL) is the second most common neoplasm among patients with AIDS. One of the major clinical characteristics of AIDS-associated NHL is the high frequency of extranodal involvement, including the gastrointestinaltract, at initial presentation. Methods: From January 1997 to December 2004, 8 cases of NHL of the digestive tract and anexal glands (liver and parotid gland) were observed at the HIV/AIDS division of the Infectious Diseases F J Muñiz Hospital from Buenos Aires,Argentina. All patients were staged by computed tomography scanning and bone marrow examination, in addition to the endoscopic evaluation. Results: All patients were males; 4 were heterosexual, 2 homosexual, and 1 were a hemophilic and an intravenous drug abuser. The median age was 42 years and the median CD4 T cell count was 87 cells/uL at the time of the diagnosis of neoplasm. No patient was receiving highly active antiretroviral therapy (HAART) at lymphoma diagnosis. The global incidence of AIDS-associated lymphomas (central nervous system lymphomas, non-Hodgkin lymphomas and Hodgkin lymphoma) during the time of study was 2,9% (54 cases); 17 patients(32%) had diagnosis of systemic NHL; 10 (58,8%) of them were extranodal at the onset of clinical symptoms and 8 (80%) involvement the digestive tract and anexal glands (parotid gland, cavum, esophagus, stomach, duodenum, the right colon in 2 patients and the liver), as primary NHL of high grade and "B" phenotype. All patients presented "B" symptoms at the time of diagnosis. Primary duodenal lymphoma was the only Burkittlymphoma of this serie and we detected the Epstein-Barr virus genome in the biopsy smears of this tumor and in the hepatic lymphoma. Four patients were treated with systemic chemotherapy with granulocytic growth factor support plus highly active antiretroviral therapy (HAART); 2 of them (cavum and one of the colon) had a prolonged survival with immune reconstitution during 5 and 6... (AU)

[Non-Hodgkin's lymphomas of the digestive tract and anexal glands in AIDS patients]. / Linfomas del tubo digestivo y glándulas anexas en pacientes con SIDA. Serie de casos.

BACKGROUND: Non-Hodgkin's lymphoma (NHL) is the second most common neoplasm among patients with AIDS. One of the major clinical characteristics of AIDS-associated NHL is the high frequency of extra-nodal involvement, including the gastrointestinal tract, at initial presentation. METHODS: From January 1997 to December 2004, 8 cases of NHL of the digestive tract and anexal glands (liver and parotid gland) were observed at the HIV/AIDS division of the Infectious Diseases FJ Muñiz Hospital from Buenos Aires, Argentina. All patients were staged by computed tomography scanning and bone marrow examination, in addition to the endoscopic evaluation. RESULTS: All patients were males; 4 were heterosexual, 2 homosexual, and 1 were a hemophilic and an intravenous drug abuser. The median age was 42 years and the median CD4 T cell count was 87 cells/uL at the time of the diagnosis of neoplasm. No patient was receiving highly active antiretroviral therapy (HAART) at lymphoma diagnosis. The global incidence of AIDS-associated lymphomas (central nervous system lymphomas, non-Hodgkin lymphomas and Hodgkin lymphoma) during the time of study was 2,9% (54 cases); 17 patients (32%) had diagnosis of systemic NHL; 10 (58,8%) of them were extranodal at the onset of clinical symptoms and 8 (80%) involvement the digestive tract and anexal glands (parotid gland, cavum, esophagus, stomach, duodenum, the right colon in 2 patients and the liver), as primary NHL of high grade and "B" phenotype. All patients presented "B" symptoms at the time of diagnosis. Primary duodenal lymphoma was the only Burkitt lymphoma of this serie and we detected the Epstein-Barr virus genome in the biopsy smears of this tumor and in the hepatic lymphoma. Four patients were treated with systemic chemotherapy with granulocitic growth factor support plus highly active antiretroviral therapy (HAART); 2 of them (cavum and one of the colon) had a prolonged survival with immune reconstitution during 5 and 6 years, respectively, after the diagnosis. The median survival of the patients, which received HAART plus chemotherapy, was 33 months. The median survival of the others patients was 90 days. CONCLUSION: NHL of the gastrointestinal tract is a severe complication of advanced HIV/AIDS disease. Early diagnosis followed by chemotherapy plus HAART are necessary to improve the prognosis and the survival of these patients.

Structural aberrations of chromosomes 17 and 12 in chronic B-cell disorders.

OBJECTIVES: Genomic aberrations can now be identified in approximately 80% of chronic lymphocytic leukemia, small lymphocytic lymphoma (CLL/SLL) patients. In the present study, four new structural changes involving chromosomes 17 and 12 in CLL/SLL patients are described. METHODS: Five patients were selected for inclusion in the present report among a total of 92 cases with diagnosis of CLL/SLL. Cytogenetic studies and fluorescence in situ hybridization (FISH) analysis to detect some of the most frequent cryptic aberrations occurring in CLL/SLL patients were performed. Clinical studies are also described. RESULTS: Four cases showed structural rearrangements of chromosome 17. A psu dic(17;2)(p11.2;p21), leading to p53 deletion, was observed in a patient who developed a mixed cellularity Hodgkin's disease coexisting with the CLL/SLL in the same lymph node. Epstein Barr virus was detected in the Reed-Sternberg cells. Two cases had a balanced translocation t(2;17)(p21;q23). Both patients showed trisomy 12 and clonal evolution and one of them also had 11q deletion. In addition, a der(17)t(12;17)(q13;q25) as a part of a complex karyotype, and a complex translocation t(5;12;19) (q15;p11;q13) were also found. Four patients had an adverse clinical outcome and died because of disease progression. CONCLUSIONS: Four unreported nonrandom chromosome aberrations in CLL/SLL patients, one of them who might represent a new recurrent abnormality, are described. These uncommon abnormalities, mostly associated with evolving disease, may have implications for the understanding of genetic events associated with disease progression in this pathology.

Efectividad del Tamizaje Mamográfico en la Reducción de la mortalidad por cáncer de mama / Effectiveness of Mammographic Screening in Reducing Mortality from Breast Cancer

El cáncer de mama (CM) es el carcinoma más frecuente a nivel mundial y la primera causa de muerte por cáncer en mujeres en todo el mundo. El diagnóstico más temprano debería traducirse en una reducción de la mortalidad por la enfermedad, disminución en la agresividad de los tratamientos (cirugía, quimioterapia, etc.) y mejoras en la calidad de vida de las mujeres afectadas. La base racional de los procedimientos de tamizaje es la mayor tasa de curación en las mujeres con CM de pequeño volumen El objetivo de los programas de tamizaje es reducir la mortalidad por cáncer de mama. Hasta ahora, el único método de tamizaje que ha probado ser efectivo en el cumplimiento de este objetivo ha sido la mamografía. Los ensayos clínicos más relevantes han reportado que el tamizaje entre mujeres de 50 y 70 años ha reducido la mortalidad por cáncer de mama entre 20 y 30

. El Programa Nacional de Control de Cáncer de Mama (PNCM) se ha realizado un análisis de la evidencia científica disponible acerca del efecto de la mamografía como método de tamizaje para reducir la mortalidad por cáncer de mama.