Compromiso ganglionar extracapsular en pacientes con cáncer gástrico: determinación del valor pronóstico / Prognostic value of extracapsular lymph node involvement among patients with gastric cancer

Background: Extracapsular lymph node involvement has a negative prognosis in malignant tumors. Aim: To assess the prognostic importance of extracapsular lymph node involvement in patients with gastric cancer with lymph node metastases. Material and Methods: Clinical and morphological features and survival of patients with gastric cancer and lymph node involvement operated between 1986 and 2003, were analyzed. Patients with and without extracapsular involvement were compared. Results: During the study period, 459 gastrectomies were performed, 312 patients (68 percent) had lymph node involvement and 144 (31 percent) had extracapsular involvement. Patients with and without extracapsular involvement were followed for a median of 10 (range 1 to 120) and 41 (range 1 to 193) months, respectively. Five years actuarial survival for patients with and without extracapsular involvement was 23 and 40 percent respectively. Extracapsular lymph node involvement and level of wall infiltration were identified as prognostic factors using a multivariate analysis. Conclusions: Extracapsular lymph node involvement is an independent risk factor for mortality among patients with gastric cancer.

Carcinoma epidermoide oral y orofaríngeo: estudio clínico-patológico / Oral and oropharingeal squamous cells carcinoma: clinico-pathological study

Introduction: Oral cancer is a common disease in many parts of the world, in Chile only accounts for 1.6 percent of all cancers. The majority is squamous cell carcinoma with important clinical, epidemiological and pathological differences between lip, oral and orofaringeal locations. Objective: To analyze clinical and pathological characteristics of oral and oropharingeal squamous cell carcinoma in Temuco, Chile. Materials and Methods: A descriptive, retrospective study of all diagnosed cases in 15 years (1994 and 2008). The patients were analyzed according to gender, age; and the tumors were classified based on anatomic location, size, macroscopical findings and degree of differentiation. Results: We found 93 carcinomas, with male to female ratio of 5:1, average age 67 years. Patients under 50 years accounted for only 8 percent of cases. The most common sites were lower lip, tongue and gingiva, with an average size of 28 mm, which increased towards orofarinx and more than half were moderately differentiated. Conclusions: In our region, this carcinoma most often affects the seventh decade of life and male population and has similar characteristics to those in other countries which is predominantly. The size at diagnosis is significant. The detection of some differences in the group with mapuche surnames warrants a study with a larger number of cases.

Introducción: El cáncer oral es una enfermedad frecuente en muchas partes del mundo, en Chile corresponde al 1,6 por ciento del total de cánceres. La gran mayoría corresponde a carcinoma epidermoide, con importantes diferencias clínicas, epidemiológicas y patológicas entre las localizaciones labial, intraoral y orofaríngea. Objetivo: Analizar las características clínicas y patológicas del carcinoma epidermoide oral y orofaríngeo en Temuco, Chile. Material y Método: Estudio descriptivo, retrospectivo de todos los casos diagnosticados en 15 años (1994 y 2008), en el Hospital Regional de Temuco. Los pacientes fueron analizados de acuerdo a género, edad, y los tumores fueron clasificados basados en su localización anatómica, tamaño, características macroscópicas y grado de diferenciación. Resultados: Se encontraron 93 carcinomas, con relación hombre:mujer de 5:1, edad promedio 67 años. Pacientes menores a 50 años correspondían sólo al 8 por ciento de los casos. Las localizaciones más frecuentes fueron labio inferior, lengua y encía, con un tamaño promedio de 28 mm, el que aumentó hacia la orofarinx, más de la mitad eran moderadamente diferenciados. Conclusiones: En nuestra región, este carcinoma afecta con mayor frecuencia a la séptima década de la vida y a población masculina y posee características similares a las descritas en otros países donde predomina la raza blanca. El tamaño al diagnóstico es considerable. La detección de algunas diferencias en el grupo con apellidos mapuches amerita un estudio con un mayor número de casos.

Cáncer gástrico sin compromiso ganglionar linfático (pN0): características demográfico-patológicas y factores pronósticos / Prognostic factors for gastric cancer without lymph node involvement

Background: The absence of lymph node involvement (N0) in gastric cancer is associated with a better survival. However some N0 gastric tumors still have a bad prognosis. Aim: To study demographic and morphological variables associated with prognosis in N0 gastric carcinoma. Material and Methods: Review of pathologica records of a regional general hospital, identifying patients with a N0 gastric cancer surgically excised between 1986 and 2003. Results: In the study period, 459 gastrectomies were performed for gastric cancer and in 32 percent, the tumor was devoid of lymph node involvement. These later patients were followed for a median of 64 months with a 71 percent fve years actuarial survival. Bivariate analysis identifed age, tumor size, gastric wallinfiltration, pathological type according to Lauren and Ming, lymphovascular involvement, number of lymph nodes excised and TNM stage as prognostic values Multivariate analysis disclosed the level of gastric wallinfiltration, the presence of a poorly differentiated tumor, lymphatic vascular involvement, number of excise lymph nodes and tumor size as independent prognostic factors. Conclusions: N0 gastric tumors are found in 32 percent of gastrectomies for gastric cancer and have a 71 percent fve years actuarial survival. Gastric wallinfiltration, pathological degree of differentiation tumor size and lymphovascular involvement are independent prognostic factors.

Factores asociados al pronóstico de pacientes operados por cáncer gástrico avanzado / Pathological factors associated with survival in advanced gastric cancer

Background: The degree of tumor infiltration and lymph node involvement are the most relevant pathological features to determine prognosis of advanced gastric cancer. Aim: To determine the association between clinical and pathological features of advanced gastric cancer and patient survival. Material and Methods: The pathological records of patients with advanced gastric cancer subjected to gastrectomy and lymph node excision between 1986 and 2007 were analyzed. Follow up was performed according to data in the clinical records and death certificates obtained at the Chilean National Death Registry. The main outcome analyzed was survival after surgery. Results: The records of 299 patients aged 62 +/- 11 years (68 percent males), were analyzed. Mean follow up ranged from 1 to 206 months. Five and 10 years actuarial survival was 39 and 34 percent, respectively. The pathological predictors of survival were microscopic tumor stage, tumor size and location, Bormann classification, infiltration level, degree of differentiation, pathological type of tumor according to Lauren, Ming y Nakamura, lymph node involvement and the absence of residual tumor after surgical excision. Conclusions: The pathological study of the surgical piece in advanced gastric cancer has important prognostic implications.

Introducción: El estudio de la pieza operatoria de pacientes resecados por cáncer gástrico (CG) ha permitido identificar variables anatomo-patológicas con valor pronóstico en la supervivencia (SV) y recurrencia de estos pacientes, siendo el compromiso ganglionar linfático y nivel de infiltración tumoral, los factores más relevantes identificados. El objetivo de este estudio es determinar asociación entre variables clínicas y morfológicas con la SV de pacientes resecados por CG avanzado (CGA). Material y Método: Estudio de cohorte retrospectiva. Se estudiaron variables clínicas y morfológicas de 299 pacientes operados por CGA entre enero de 1986-diciembre de 2001. Los datos fueron obtenidos desde la Unidad de Anatomía Patológica del Hospital Hernán Henríquez Aravena de Temuco. Se aplicó estadística descriptiva y analítica; confección de curvas de supervivencia, y finalmente se aplicaron modelos de regresión logística para realizar ajuste, calcular odds ratios y sus respectivos intervalos de confianza de 95 por ciento. Resultados: La cohorte tuvo una mediana de edad de 63 años y el 68 por ciento de ella correspondió al género masculino. Con una mediana de seguimiento de 21 meses (1 a 206), se observó una SV actuarial global a 5 y 10 años de 39 por ciento y 34 por ciento respectivamente. En el análisis bivariado, se verificó asociación con la SV en: etapa tumoral macroscópica, localization y tamaño tumoral, tipo según Bormann, nivel de infiltración, grado de diferenciación histológico, tipo histológico según Lauren, Ming y Nakamura, estado ganglionar linfático (N), estadio TNM y resultado de la resección realizada. Conclusiones: Las variables mencionadas deben ser cuidadosamente evaluadas al momento de decidir terapias en pacientes con CGA.

Factores morfológicos asociados al pronóstico de pacientes operados por cáncer gástrico incipiente / Pathological features associated with survival in early gastric cancer

Background: Early gastric cancer corresponds to those tumors that only involve mucosa and submuco-sa. It is associated with a high survival rate. Aim: To determine pathological factors associated with survival in early gastric cancer. Material and Methods: Analysis of pathological records of 106 patients, with a median age of 63 years (60 percent> males), subjected to a gastrectomy for early gastric cancer. Follow up was performed according to data in the clinical records and death certificates obtained at the Chilean National Death Registry. Results: Five years global survival of patients was 91 percento. Lymph node involvement was more common among tumors bigger than 35 mm, with a low degree of differentiation and among those tumors classified as diffuse according to Lauren. Survival was significantly lower for bigger tumors, those with of a low degree of differentiation, diffuse tumors according to Lauren and those with lymph node involvement. Conclusions: Early gastric cancer has a high five years survival. Bigger tumors, those with a low degree of differentiation and those with lymph node involvement are associated with lower survival rates.

Introducción: El cáncer gástrico incipiente (CGI) es aquel que compromete la mucosa o submucosa gástrica independientemente del compromiso ganglionar linfático, estimándose su prevalencia en Chile inferior al 20 por cientoo. El objetivo de este estudio es determinar prevalencia de CGI y asociación de variables biode-mográficas y morfológicas con la supervivencia (SV) de pacientes resecados por CGI. Material y Método: Estudio de cohorte retrospectiva. Se estudiaron variables biodemográficas y morfológicas de 106 pacientes resecados por CGI entre 1986-2007. Se aplicó estadística descriptiva y analítica; confección de curvas de SV, y finalmente se aplicaron modelos de regresión logística para realizar ajuste, calcular odds ratio y sus respectivos intervalos de confianza de 95 por ciento. Resultados: 15 por ciento correspondió a CGI. La mediana de edad fue 63 años y el 60 por ciento correspondió a género masculino con una SV global a 5 años de 91 por ciento. Se observaron diferencias estadísticas significativas entre tumores mucosos y submucosos en cuanto a la localización tumoral y compromiso linfonodal junto con presentarse el compromiso nodal más frecuentemente en tumores > 35mm poco diferenciados y difusos de Lauren. El análisis multivariado identificó como factores asociados a la SV: tamaño tumoral, grado de diferenciación histológica en su variedad poco diferenciado, tipo difuso de Lauren y compromiso ganglionar linfático. Conclusiones: Se verificó una prevalencia de CGI de 15 por ciento, los que resecados presentan SV de 91 por ciento a 5 años. El compromiso linfonodal es un factor asociado a la SV; y además, se relaciona con tamaño tumoral, tipo histológico según Lauren, grado de diferenciación histológico y nivel de infiltración.

Puntaje de Gleason en cáncer de próstata: Correlación de la biopsia por punción y prostatectomía radical / Concordance between Gleason scores of trans rectal biopsies and the surgical piece of radical prostatectomy

Background: Gleason pathological score in prostate cancer is an importantprognostic indicator. However, the concordance between the score of trans rectal needle biopsies and the final score of the surgical piece may be variable. Aim: To analyze the concordance between Gleason scores of trans rectal prostate biopsies and those of the surgical piece obtained after prostatectomy. Material and Methods: Retrospective analysis of 168 pathological records of radical prostatectomies, performed between 1993 and 2009. All these patients had also a trans rectal biopsy performed previously. Patients with less than 12 tissue cylinders obtained during the trans rectal biopsy or incomplete data were not included in this analysis. Results: Sixty eight percent of trans rectal biopsies had Gleason scores that were concordant with those of the surgical piece. The score was higher or lower in 27 and 10 percent of biopsies, respectively. Conclusions: Gleason scores of trans rectal biopsies and those of the surgical piece were concordant in 68 percent of cases in this series of pathological records.

Linfoadenitis criptococócica mesentérica: Una rara causa de abdomen agudo. Caso clínico / Mesenteric cryptococcal lymphadenitis: Report of one case

Cryptococcosis is an invasive mycotic infection caused by Cryptococcus neoformans, an encapsulated, yeast-like fungus. It is considered an opportunist infection, since it mainly affects immunocompromised subjects. However there are isolated reports of the infection in immunocompetent subjects. Cryptococcal infection of intra-abdominal organs or tissues is extremely rare. We report a 21-year-old HIV positive male that, during the treatment of a meningeal cryptococcosis, presented a clinical picture of an acute abdomen suggesting acute appendicitis. The patient was operated, finding enlarged mesenteric lymph nodes forming conglomerates and a macroscopically normal appendix. The conglomerated lymph nodes and the appendix were excised. The pathological study of the surgical piece revealed an intra abdominal cryptococcal lymphadenitis and a normal appendix.

Carcinoma de células en anillo de sello gástrico: descripción clínico-morfológica y valor pronóstico / Prognosis of signet ring cell carcinoma of the stomach

Background: Signet ring cell carcinoma of the stomach corresponds to 3 to 39 percent of all gastric malignant tumors, and its prognostic significance is not well known. Aim: To compare the prognosis of signet ring cell carcinoma of the stomach with other types of gastric cancer. Material and Methods: Review of 451 patients operated for gastric carcinoma. Signet ring cell carcinomas were compared with the rest of tumors. Results: One hundred twenty tumors (27 percent) were signet ring cell carcinoma, they were more commonly located in the lower third of the stomach, were less differentiated, bigger and had more lymph nodes involved. Patients with this variety of tumor were younger, more often women and their survival was lower, even when separating incipient and advanced tumors. Conclusions: Signet ring cell carcinoma of the stomach had a worst prognosis that other type of gastric tumors.

Introducción: La incidencia de carcinoma gástrico (CG) de células en anillo de sello (CAS) varía de 3 por ciento a 39 por ciento. Trabajos de supervivencia en pacientes con tumores gástricos reportan resultados contradictorios en cuanto a la importancia pronostica del tipo histológico CAS respecto a los otros tipos histológicos. El objetivo del estudio es describir y evaluar la importancia pronostica del tipo histológico CAS comparado con los carcinomas no anillo de sello (CNAS). Material y Método: Estudio de cohorte retrospectiva. Se estudiaron variables clínicas y morfológicas de 451 pacientes operados por CG en el Hospital Hernán Henríquez Aravena de Temuco entre Enero/1986-Diciembre/2001 agrupándose para el análisis según el diagnóstico histopatológico en CAS y CNAS. Se realizó un análisis exploratorio de los datos y posteriormente se aplicó estadística descriptiva con cálculo de medidas de tendencia central y extrema; y estadísticas analíticas, aplicando Chi cuadrado de Pearson y test exacto de Fisher para variables categóricas, T-Student para variables continuas, Kaplan-Meier y Log-rank test para análisis de supervivencia. Resultados: Un 27 por ciento (120) correspondió a CAS observándose diferencias estadísticamente significativas entre los grupos CAS y CNAS para las siguientes variables: género, edad, localización y tamaño tumoral, grado de diferenciación histológico y compromiso ganglionar linfático. El análisis de supervivencia demostró un peor pronóstico para el grupo de CAS (p = 0,02). En el análisis por separado de tumores incipientes y avanzados respecto del tipo histológico, no observamos diferencias significativas para lesiones incipientes (p = 0,07) mientras que para lesiones avanzadas el CAS se asocia a un pronóstico desfavorable (p < 0,0001). Conclusiones: Observamos en nuestra serie un peor pronóstico asociado al tipo histológico CAS respecto a los otros tipos histológicos (CNAS), información crucial que, aportada al clínico, deberá ser...

Hallazgos morfológicos en casos fatales de síndrome cardiopulmonar por hantavirus: Estudio de 7 autopsias / Morphological findings in fatal cases of hantavirus cardiopulmonary syndrome: Report of 7 autopsies

Introducción: El síndrome cardiopulmonar por hantavirus (SCPH) es una enfermedad infecciosa aguda, caracterizada por insuficiencia cardio-respiratoria súbita y alta mortalidad, causada por un virus ARN del género Hantavirus, familia Bunyaviridae. Un 15 por ciento de los casos chilenos ha sido pesquisado en la Araucanía. Objetivo: Conocer en casos fatales de SCPH, sus características clínicas y morfológicas. Material y Método: Estudio descriptivo-retrospectivo de siete casos fatales con examen postmortem, de SCPH, atendidos entre 1997 y 2009 en el Hospital Regional de Temuco. Resultados: Los casos fueron principalmente pacientes jóvenes, rurales, con un cuadro de compromiso respiratorio progresivo, con leucocitosis, trombopenia e infiltrado pulmonar intersticial bilateral. Los principales hallazgos histopatológicos fueron un acentuado edema pulmonar intra-alveolar e intersticial, con escaso daño epitelial e infiltrado mono-nuclear y leve edema miocárdico con infiltrado mononu-clear. Conclusiones: Los antecedentes epidemiológicos, clínicos y laboratorio permiten sospechar SCPH. En los casos fatales la autopsia permite diferenciar el SCPH de otras patologías similares y aporta tejidos para confirmar el diagnóstico.

Introduction: Hantavirus cardiopulmonary syndrome (HCPS) is an acute infectious disease characterized by sudden cardiorespiratory failure and high mortality, caused by a RNA virus of the genus Hantavirus, family Bunyaviridae, 15 percent of Chilean cases have been detected in the Araucania Region. Objective: To determine in fatal cases of HCPS, clinical and morphological characteristics. Materials and Methods: Descriptive-retrospective analysis of seven fatal cases with postmortem study of HCPS, attended between 1997 and 2009 at the Hospital of Temuco, Chile. Results: Cases were young patients from rural areas, and presented as an illness of progressive respiratory failure, with leukocytosis, thrombocytopenia and bilateral interstitial pulmonary infiltrates. Main morphological findings were marked intersticial and intraalveolar pulmonary edema, with minimal epithelial injury and mononuclear cell intersticial infiltrate and mild edematous intersticial inflamatory process. Conclusions: Epidemiological, clinical and laboratory background allow to suspect HCPS. In fatal cases, the autopsy makes possible to discard other similar pathologies and provide tissue for confirmation of the disease.

Descripción clínico-morfológica y factores pronósticos en carcinomas de apéndice cecal: estudio de cohorte / Appendiceal malignant tumors: review of 84 cases

Background: Malignant appendiceal tumors account for only 0.5 percent of all gastrointestinal tumors and there are usually diagnosed during the pathological study of excised appendices. Aim: To assess the factors influencing the survival of patients with appendiceal carcinomas. Material and Methods: Retrospective review of records of all primary appendiceal carcinomas diagnosed in the pathology unit of a regional hospital between 1993 and 2008. The surgical procedure, clinical history, morphological features of tumor and survival were recorded. Results: Eighty four patients aged 32 ± 15 years (44 women) with appendiceal carcinoma were identified. In 93 percent of patients, the clinical diagnosis was acute appendicitis. Sixty one patients (73 percent) had a carcinoid tumor, 20 (24 percent) an adenocarcinoma and three (3 percent), an adenocarcinoid tumor. Preoperative suspicion of a malignant tumor, level of tumor infiltration, pathological type, involvement of surgical borders, tumor size over 2 cm in the case of carcinoid tumors and the degree of differentiation of adenocarcinomas, had prognostic value. For adenocarcinomas, performing a right hemicolectomy significantly improved survival. Conclusions: Carcinoid tumors are the most common malignant tumor of the appendix. A right hemicolectomy may improve the survival of patients with appendiceal adenocarcinomas.

Introducción: Los tumores malignos del apéndice cecal representan tan sólo el 0,5 por ciento de todas las neoplasias gastrointestinales. Su diagnóstico generalmente no es sospechado por el clínico, siendo su diagnóstico un hallazgo durante el examen de la pieza operatoria. Algunos de estos tumores presentan buena supervivencia con la sola apendicetomía, aunque en ocasiones es necesario realizar tratamientos complementarios. El objetivo de este estudio es determinar la asociación entre variables clínicas y morfológicas con la supervivencia de pacientes con carcinomas del apéndice cecal y analizar el tratamiento quirúrgico realizado. Material y Método: Cohorte retrospectiva de 84 pacientes con carcinomas apendiculares diagnosticados en el Hospital Hernán Henríquez Aravena de Temuco entre los años 1993-2008. Se estudiaron variables clínico-morfológicas, el tratamiento quirúrgico realizado y la supervivencia para estos pacientes. Se utilizó estadística descriptiva y analítica, aplicando Chi-cuadrado y test exacto de Fisher para variables categóricas y T-Student para variables continuas; y prueba Log-rank (Mantel-Cox) para comparación de curvas de supervivencia con un IC de 95 por ciento. Resultados: Del total de apendicectomías (18.563) se verificaron 84 casos (0,45 por ciento); 48 por ciento hombres y 52 por ciento mujeres con una edad promedio de 31,9 +/- 15 años. En el 93 por ciento de los casos el diagnóstico clínico fue apendicitis aguda. Correspondieron a carcinoide, adenocarcinoma y adenocarcinoide en 61 (73 por ciento), 20 (24 por ciento) y 3 (3 por ciento) casos respectivamente. En el análisis bivariado las siguientes variables mostraron asociación pronóstica estadísticamente significativa: sospecha pre-operatoria (p = 0,009), nivel de infiltración tumoral (p = 0,04), tipo histológico (p = 0,009), compromiso de bordes quirúrgicos (p < 0,001), tamaño tumoral > 2 cm en tumores carcinoides (p = 0,001) y grado de diferenciación en adenocarcinomas...

Cáncer gástrico en una región de Chile: comparación de variables clínicas y morfológicas en dos períodos (1986-1995 y 1996-2005) / Changes in morphological an clinical characteristics of gastric cancer from 1986 to 2005

Background: In the last decade, changes in therapy and on the epidemiological and pathological behavior of gastric cancer have occurred in Chile. Aim: To compare the natural history of gastric cancer in two periods (1986-1995 and 1996-2005) in the ninth region of Chile. Material and Methods: Medical records of 563 gastrectomies for gastric cancer, performed between January 1986 and December 2005 and kept at a Pathology Unit of a public hospital, were reviewed. Clinical and morphological variables were analyzed (histological Lauren type, differentiation degree, location and macroscopic type, infiltration level, number of resected and involved lymph nodes). Results: A significant increase in the frequeney of the diffuse type of gastric cancer was observed in the seeond period in study, with a concomitant deerease of the intestinal type. A reduction in tumor size and number of excised lymph nodes was also observed. Conclusions: In the seeond study period, morphological changes in gastric cancer, were observed.

Introducción: El cáncer gástrico (CG) es la primera causa de muerte por cáncer en Chile (tasa de mortalidad general de 19,5 x 10(5) y 24,8 x 10(5) habitantes a nivel nacional y IX Región respectivamente). Se han descrito cambios epidemiológicos, histopatológicos y de tratamiento para CG. El objetivo de este estudio es describir la historia natural del CG en la IX región de Chile comparando dos periodos (1986-1995 y 1996-2005). Material y Método: Cohorte histórica. Se incluyeron todos los casos de gastrectomías por CG de la Unidad de Anatomía Patológica del Hospital Hernán Henríquez Aravena entre Enero de 1986 y Diciembre de 2005 (n = 563). Se estudiaron variables clínicas (edad, género y estadio TNM) y morfológicas (tipo histológico según Lauren, grado de diferenciación, localización y tipo macroscópico de la lesión, nivel de infiltración, número de ganglios resecados y comprometidos por el tumor). Se aplicó estadística descriptiva y analítica usando t-test y ANOVA para variables continuas, chi² y exacto de Fisher para variables categóricas. Resultados: De las características estudiadas, se evidenció un incremento estadísticamente significativo del tipo difuso en el segundo período en estudio a expensas de un decremento del tipo intestinal; así también una disminución en el tamaño tumoral y número de ganglios linfáticos resecados. Conclusiones: Se verificaron cambios morfológicos del CG experimentados a nivel regional en los períodos estudiados.

Validez diagnóstica de la biopsia intraoperatoria en cirugía de lesiones mamarias palpables / Diagnostic value of frozen section biopsy during surgery for breast lesions or neoplasms

Background: During the surgical treatment of breast neoplasms (benign or malignant), frozen section biopsy is frequently requested to assess the kind of lesion and determine the surgical margins. Aim: To assess the diagnostic yield of frozen section breast biopsy. Material and methods: AH the pathological reports of frozen section biopsies and definitive biopsies of 337 women aged 26 to 88 years, operated for suspected breast neoplasms between 2002 and 2006, were reviewed. The sensitivity, specificity and predictive value of frozen section biopsy, were calculated using the definitive biopsy as the gold standard. Results: The definitive biopsy confirmed the presence of cancer in 290 women (86 percent). There were two false negative (0.59 percent) and no false positive frozen section biopsies for cancer detection. The sensibility for cancer detection was 99.3 percent and the specificity 100 percent. The positive predictive value was 100 percent and the negative predictive value 96.1 percent. The diagnosis of phyllodes tumor was missed by frozen section biopsy in three cases. The margins were informed in the 258 frozen section biopsies (79 percent) and in 59 cases (18 percent), these were positive for cancer. Conclusions: Frozen section biopsy is useful and reliable for cancer detection and margin status assessment in breast cancer surgery (RevMéd Chile 2009; 137: 1173-8).

Adenocarcinoma gástrico primario concomitante con tumor estromal gastrointestinal: Reporte de un caso y revisión de literatura / Concomitant presence of a gastric adenocarcinoma and gastrointestinal stromal tumor: Report of one case

The concomitant presence of a primary gastric adenocarcinoma and a gastrointestinal stromal tumor in the stomach is uncommon. We report a 68-year-old male with an advanced gastric adenocarcinoma. During gastrectomy, a nodular intramural lesion was found. The pathological study, revealed a gastrointestinal stromal tumor, positive form CD117. After six months of follow up, there is no evidence of recurrence of either tumor.

Estudio de patrones de metilación génica en tumores del tubo digestivo / Gene methylation patterns in digestive tumors

Background: The loss of tumor suppresor gene function damages the defensive mechanisms that protect the indemnity of genetic material. Promoter gene methylation is one of the inactivation mechanisms of suppressor genes. Aim: To study the methylation pattern of a group of genes in biopsy samples of gastrointestinal tumors. Material and methods: Forty eight gastric, 25 gallbladder, 24 colon and 6 pancreas cancer biopsy samples were randomly selected. The methylation pattern of CDH1, FHIT, CDKN2A, APC and MLH1 genes, was studied using a specific polymerase chain reaction test for methylation. Demographic, morphological and follow up variables of patients bearing the tumors were also analyzed. Results: The general methylation frequency of CDH1, FHIT, CDKN2A, APC and MLH1 genes was 64.1, 56, 39.8, 18.1 and 34 percent respectively. In gastric cancer samples there was a correlation between APC gene methylation and well differentiated tumors; between CDH1 methylation and Lauren diffuse type and the presence of three or more metastasic lymph nodes; between FHIT, CDKN2A and CDH1 gene methylation and male gender. In ¡ess differentiated gallbladder tumors, the frequency of CDH1 methylation was higher. There was a tendency towards a lower survival in colon and gastric cancer when MLH1 (p =0.07) y CDKN2A (p= 0.06) were methylated, respectively. Conclusions: An abnormal methylation pattern was associated with morphological features in gastric and gallbladder cancer and with a tendency towards a lower survival in colon and gastric cancer.

Adenocarcinoma endometrial concomitante con tumor estromal benigno del endometrio / Endometrial carcinoma concomitant with endometrial stromal tumor benign

La asociación de tumor epitelial y estromal maligno es muy infrecuente, habiendo pocos casos reportados, más infrecuente aún es la asociación de tumor epitelial maligno y tumor estromal benigno. Se presenta el caso de mujer de 65 años con diagnóstico preoperatorio de carcinoma endometrial, que durante el procesamiento de la pieza quirúrgica se encontró además una lesión intramural nodular estromal benigna, sin continuidad entre ambas lesiones.

The association of epithelial and stromal malignant neoplasm is very rare, with few reported cases, rarer still is the prescence of malignant epithelial tumor and stromal benign tumor. We present the case of women aged 65 with preoperative diagnosis of endometrial carcinoma, which in the pathological examination was found an intramural benign endometrial stromal lesión, without continuity between both tumors.

Expresión inmunohistoquímica del complejo E-caderina-catenina en cáncer gástrico: Relación con variables clínico-morfológicas y sobrevida de pacientes / Immunohistochemical expression of the E-cadherin-catenin complex in gastric cancer

Background: The E-cadherin/catenin complex plays an essential role in the control of epithelial differentiation. Abnormal expression in tumors correlates with histological grade, advanced stage and poor prognosis. Aim: To evaluate the expression pattern of E-cadherin/catenin complex in gastric carcinoma and analyze their association with tumor clinicopathological features and patient survival. Material and Methods: Inmunohistochemical staining of E-cadherin, alpha and ß-catenin was performed from paraffin specimens of 65 gastric carcinomas. Results: Abnormal expression of E-cadherin, alpha and ß-catenin was demonstrated in 82 percent, 85 percent and 88 percent of gastric carcinomas, respectively. There was a significant correlation between abnormal expression and Lauren pathological classification and depth of infiltration, but not with tumor stage, positive lymph node metastases and survival. Conclusion: Abnormal expression of E-cadherin, alpha and ß-catenin occurs frequently in gastric carcinoma and correlates with histological grade.

Quiste aneurismático del maxilar superior. Reporte de un caso / Aneurysmal bone cyst of the maxilla. Report of one case

Aneurysmal bone cysts are benign fibro osseous lesions, rarely present in maxillary region. We report the CT and morphological findings of aneurysmal bone cyst of the maxilla in a 15 years old female. The patient was subjected to a maxillectomy, preserving the orbit floor. The postoperative evolution has been uneventful. The tumor mainly involved the maxillary sinus with extension to the orbit wall and osseous palate. Very few cases of aneurysmal bone cysts of the maxilla have been reported in the literature.

Estudio del patrón de metilación génico en el cáncer gástrico en Chile / Promoter methylation profile in gastric cancer

Background:Promoter genomic DNA methylation is an important inactivation mechanism of tumor suppressor genes. This genetic-molecular pathway for cancer may separate a subset of patients with different prognoses and eventually different responses to specific therapies. Aim: To analyze the methylation pattern of important genes related to different carcinogenic mechanisms in patients with gastric cancer (GC) and the relationship with its morphological features and biological behavior. Material and methods: Forty-seven fresh-frozen GC samples were selected. The methylation-specific PCR (MSP) test was used to analyze promoter methylation status for genes MLH1, CDKN2A (p16), APC, CDH1 (Cadherin E) and FHIT. Follow-up and complete morphological features were obtained for all cases. Results: We found methylation in at least one of the genes studied in 83% of the cases. The frequencies of promoter hypermethylation of MLH1, CDKN2A, APC, CDH1 and FHIT were 31%, 43%, 46%, 80% y 62%, respectively. We found a relationship between APC methylation and good histological differentiation (p=0.03); CDH1 methylation with diffuse type by Lauren and 3 or more metastasic lymph nodes (p <0.05); FHIT, CDKN2A and CDH1 methylation and female condition (p <0.04). We also found a non-significant relationship between CDKN2A methylation and better survival (p=0.07). Conclusions: The high frequency promoter methylation found confirms its importance in gastric carcinogenesis. The finding of alterations in the methylation pattern of genes studied and its association with prognostic factors is a helpful tool in the search for new criteria in clinical and therapeutic decision making.

Detección de micrometástasis en médula ósea de pacientes con cáncer de vesícula biliar / Detection of bone marrow micrometastases in patients with gallbladder cancer

Background: There is a very strong documented correlation between the appearance of cancer cells in blood and occurrence of metastasis in gastrointestinal cancer. Aim: To determine MUC1, CK19, CK20 and CEA mRNA expression in bone marrow of patients with gallbladder cancer and evaluate its clinical significance. Material and methods: Sixty eight samples were analyzed, 38 bone marrow samples of gallbladder cancer patients, 20 healthy donors, and 10 frozen samples of gallbladder cancer. Nested reverse transcriptase-polymerase chain reaction (nested RT-PCR) was used to analyze mRNA expression. Results: All frozen tumors were positive for CEA, CK19, and MUC1 mRNA and 70 percent were positive for CK20. Seventeen of 20 donor samples were positive for MUC1 and only one sample from donors was positive for both CK20 and CK19 mRNA. Among the 38 blood and bone marrow samples of gallbladder cancer patients, the expression of MUC1, CK19, CK20, and CEA, mRNA was 60.5 percent (23/38), 31.6 percent (12/38), 7.9 percent (3/38), and 7.9 percent (3/38), respectively. Disregarding the MUC1 results. 37 percent (14/38), 13 percent (5/38) and 5 percent (2/38) were positive for one, two and three markers respectively. Not significant differences were found in survival with a follow up to 12 months. Conclusion: Our results indicate that the molecular detection of tumor cells in bone marrow in patients with gallbladder carcinoma is technically possible, being CEA, CK19 and CK20 gene expression the best markers. The MUC1 gene expression marker was highly unspecific and it should not been considered. The detection of bone marrow micrometastasis might be helpful in prognosis and the selection of clinical treatment but a larger series with a longer follow-up should be studied.

Relación de la genotipificación de Helicobacter pylori con la forma e intensidad de la gastritis en población adulta portadora de patología gástrica benigna / Association between helicobacter pylori genotype and the severity of gastritis in infected adults

Background: The damaging capacity of Helicobacter pylori is variable and depends, in part, on its genetic polymorphism. Aim: To study H pylori genes vacA, cagA and iceA and the relationship of these genotypes with the features of acute damage in chronic gastritis. Material and methods: Gastric endoscopic biopsies were obtained in 75 adults for pathological study and genetic typification of H pylori by specific PCR. Results: In only 64 cases, complete information was available. In 53 of these, there was H pylori infection demonstrated by PCR. Twenty one percent had infection by two or more H pylori strains, vacA gene had genotypes s2/m2, s1/m1 and s1/m2 in 36, 25 and 8% of cases respectively, cagA gene was present in 49% of infected patients. iceA gene had genotypes iceA 1 ad iceA 2 in 15 and 60% of patients respectively. The presence of cagA or alleles s1/m1 and s1/m2 of vacA gene was directly correlated with polymorphonuclear infiltration and the severity of epithelial damage. The genotype s2/m2 of vacA gene was significantly associated with a milder or absent mucosal damage. No association was found between iceA alleles and the pathological features of gastritis. Conclusions: Alleles of vacA and cagA genes of H pilory are associated with the severity of gastric mucosal damage.