Presencia de inestabilidad microsatélite en pacientes colombianos con adenocarcinoma colorrectal / Microsatellite instability in Colombian patients with colorectal adenocarcinoma

Resumen Introducción y objetivos: la vía de inestabilidad de microsatélites (IMS) está implicada en la carcinogénesis de un 15 % de carcinomas colorrectales (CCR). La detección de esta alteración tiene relevancia en el pronóstico y en el tratamiento de los pacientes con CCR. El objetivo del presente estudio es determinar la prevalencia de IMS en CCR en una cohorte de pacientes de Bogotá, Colombia. Materiales y métodos: se evaluó por inmunohistoquímica la presencia de homólogo MutL 1 (MLH1), segregación posmeiótica aumentada 2 (PMS2), homólogo mutS 2 (MSH2) y homólogo mutS 6 (MSH6) en muestras de CCR prevenientes de colectomías. Adicionalmente, se analizaron las variables clinicopatológicas. A los casos con pérdida de MLH1 y PMS2 se les evaluó la mutación del gen BRAF. Resultados: en total se incluyeron 86 casos. La mediana de edad de los pacientes con CCR fue de 69 años, 52,3 % fueron hombres. De los pacientes con CCR, 12 (13,9 %) presentaron IMS, de los cuales 10 (83,3 %) tenían ausencia de expresión MLH1/PMS2 y 2 (16,7 %), de MSH2/MSH6. La mediana de edad de los pacientes con CCR e IMS fue de 52 años (45-76,5), 9 eran hombres y el 66,7 % de estos casos se localizaron en el colon derecho. El tipo histológico más frecuente fue adenocarcinoma moderadamente diferenciado (67 %). Los linfocitos infiltrantes al tumor fueron observados en el 83 %, la presencia de infiltrado de tipo Crohn estaba presente en el 42 %. La mutación de BRAF se observó en el 30 % de los pacientes con pérdida de MLH1 y PMS2. Conclusión: la prevalencia de la IMS en nuestra población fue de 14 %, datos similares a los observados en la población norteamericana y europea. Sin embargo, se observa que el 83 % presentó pérdida de expresión del complejo MLH1/PMS2, una prevalencia mayor comparada con otras poblaciones.

Abstract Introduction: The microsatellite instability (MSI) pathway is involved in the carcinogenesis of 15% of colorectal carcinomas (CRC). The detection of this alteration is relevant for the prognosis and treatment of CRC patients. Objective: The aim of this study is to determine the prevalence of MSI in CRC in a cohort of patients in Bogotá, Colombia. Materials and methods: The presence of MLH1, PMS2, MSH2, and MSH6 was evaluated by immunohistochemistry in CRC samples collected during colectomy. Clinicopathological variables were analyzed as well. Cases with loss of MLH1 and PMS2 were evaluated for BRAF gene mutation. Results: A total of 86 cases were included. The median age was 69 years, 52.3% were male. 12 (13.9%) patients had IMS, 10 (83.3%) had absence of MLH1/PMS2 expression and 2 (16.7%) absence of MSH2/MSH6 expression. The median age of patients with IMS was 52 years (45-76.5), of which 9 were male. 66.7% of carcinomas were located in the right colon and the most frequent histological type was moderately differentiated adenocarcinoma (67%). Tumor infiltrating lymphocytes were observed in 83% of the cases, while the presence of Crohn's-like infiltrate was present in 42%. BRAF mutation was observed in 30% of patients with loss of MLH1 and PMS2. Conclusion: The prevalence of IMS in our population was 14%, similar to the data observed in the North American and European populations. However, we observed that 83% had loss of expression of the MLH1/PMS2 complex, a higher prevalence compared to other populations.

Fibrosis retroperitoneal como causa de uropatía obstructiva. Reporte de caso / Retroperitoneal fibrosis as a cause of obstructive uropathy. Case report

Resumen La fibrosis retroperitoneal es una patología rara, en la mayoría de los casos idiopática, aunque se ha asociado a medicamentos, neoplasias y otras enfermedades de tejido conectivo. Histopatológicamente se evidencia inflamación y depósito de tejido fibrótico en el retroperitoneo y se caracteriza por cubrir los uréteres provocando lesión renal aguda obstructiva siendo ésta, la manifestación más frecuente; el diagnóstico definitivo se obtiene únicamente con biopsia y la base del tratamiento es la corticoterapia, aunque en casos severos y en resistencia a los corticoides se han usado otras terapias como los inmunomuladores. En ocasiones son necesarias las intervenciones quirúrgicas para el manejo de las complicaciones. Se presenta el caso de un hombre de 50 años que ingresó al servicio de urgencias del Hospital San José por dolor abdominal, los paraclínicos demostraron elevación de los azoados y en las imágenes diagnósticas hidronefrosis izquierda con componente de tejido blando interaortocava y periaórtico, se realizó biopsia retroperitoneal y se hizo diagnóstico de fibrosis retroperitoneal idiopática, se instauraron nefrostomías bilaterales y se inició manejo con corticoide.

Abstract Retroperitoneal fibrosis is a rare, in most cases idiopathic, pathology, although it has been associated with medications, neoplasms and other connective tissue diseases. In terms of histopathology, inflammation and deposits of fibrotic tissue in the retroperitoneum are observed and, characteristically, this covers the urethra, provoking acute obstructive kidney damage, the most frequent manifestation of the disease. The definitive diagnosis is obtained solely via biopsy, and the basis of treatment is corticotherapy, although in severe cases, and where resistance to corticosteroids exists, other treatments have been used, such as immunomodulators. Occasionally, surgical interventions are necessary to manage complications. The case of a 50-year-old man who came to the Hospital emergency service due to abdominal pain is presented. Paraclinical studies showed azotemia, and diagnostic images showed left hydronephrosis with a component of interaortocaval and periaortic soft tissue. A retroperitoneal biopsy was conducted, and a diagnosis of idiopathic retroperitoneal fibrosis was made. Bilateral nephrostomies were put in place and treatment with corticosteroids was initiated.

Frequency of Defective Mismatch Repair System in a Series of Consecutive Cases of Colorectal Cancer in a National Cancer Center.

BACKGROUND: The frequency of colorectal cancer (CRC) with defective mismatch repair (dMMR) is estimated between 5 and 15%. In our population, the frequency of dMMR is unknown. Our objective was to show the frequency of dMMR. METHODS: Determination of dMMR with immunohistochemistry was performed prospectively for 202 patients who presented consecutively with CRC for the first time at our institution. RESULTS: The median age was 59 years (IQR 47 to 68), 119 (58.9%) were women, and 43 (21.3%) cases showed dMMR. The only clinicopathological characteristics associated with dMMR were the location in the right colon and the presence of a family history of cancer. In the multivariate analysis, only the presence of the tumor in the right colon was associated with dMMR (OR = 5.823, 95%-C.I. = 2.653-12.784, p < .001). CONCLUSION: The 21.3% of the cases demonstrated a dMMR and the only clinical-pathological characteristic associated with dMMR was location in the right colon.

Localized Castleman's Disease in the Breast in a Young Woman.

Castleman's disease (CD) is a rare lymphoproliferative disorder of unknown etiology. It typically occurs in adulthood but it may also develop in childhood. Clinically, this disease may be classified as localized (unicentric) or systemic (multicentric). Six cases of breast CD have been described in the literature, and all have been reported in adults. Herein we describe the case of a 15-year-old female who presented with a slow-growing tumor in the right breast. The tumor was excised and histopathological examination demonstrated hyaline vascular variant CD. After two years of follow-up, the patient was asymptomatic without evidence of cervical or axillary lymphadenopathy.

Tumor fibroso solitario de la mama: presentación de caso y revisión de la literatura / Solitary fibrous tumor of the breast: Case report and literature review

El tumor fibroso solitario, previamente denominado hemangiopericitoma, es un tumor mesenquimal benigno compuesto por células fusiformes con forma ovoide dentro de las fibras de colágeno. Su presentación en mama es poco frecuente; se han reportado alrededor de 50 casos en la literatura. Presentamos el caso de una mujer de 36 años con lesión en la mama derecha con características fenotípicas e inmunohistoquímicas de tumor fibroso solitario. Además, realizamos una revisión de la literatura de los casos publicados (AU)

Solitary fibrous tumor, previously called hemangiopericytoma, is a benign mesenchymal tumor composed of ovoid spindle cells within collagen fibers. Its presentation in the breast is rare, with around 50 cases reported in the medical literature. We present the case of a 36-year-old woman with a right breast mass with phenotypic and immunohistochemical features of solitary fibrous tumor. In addition, we provide a review of published cases in the literature (AU)

Carcinoma prostático: Factores prequirúrgicos asociados con extensión extraprostática y márgenes positivos Hospital de San José, Bogotá DC, Colombia / Prostate carcinoma: Preoperative factors related with extraprostatic extention and positive margins Hospital de San José, Bogotá DC. Colombia

El cáncer de próstata es causa importante de mortalidad y es invaluable la estadificación adecuada de los pacientes para minimizar las complicaciones del tratamiento quirúrgico. El objetivo es describir las características prequirúrgicas de los pacientes con extensión extraprostática y/o márgenes positivos en casos de adenocarcinomas de próstata tratados mediante prostatectomía radical abierta en el Hospital de San José de Bogotá DC, de enero 2001 a diciembre 2007. Se estudiaron 34 pacientes a quienes se les determinó el puntaje de Gleason del espécimen de prostatectomía, el TNM patológico, la presencia o no de extensión extraprostática y los márgenes quirúrgicos positivos, los cuales se relacionaron con factores prequirúrgicos como edad, niveles séricos de PSA, TNM clínico y puntaje de Gleason en biopsia. La media de edad fue 64.2 años (DE 6.7). La frecuencia de márgenes quirúrgicos positivos y extensión extraprostática fue 44 y 47%. Se observó mayor compromiso de márgenes quirúrgicos y extensión extraprostática cuando el puntaje de Gleason fue de 8 ó más.

Prostate cancer is a leading cause of mortality thus adequate staging is of incalculable value for minimizing surgical treatment complications. The objective of this study performed at Hospital de San José, Bogotá DC from January 2001 to December 2007 is to describe the preoperative data of patients with a prostate adenocarcinoma with extraprostatic extension and/or positive margins treated with an open radical prostatectomy. The Gleason score, pathologic TNM stage, presence or non presence of extraprostatic extension and positive surgical margins of the prostatectomy specimen were determined in 34 participants and related with preoperative factors such as age, PSA level, clinical TNM stage and biopsy Gleason score. The median age was 64.2 years (SD 6). The rate of positive surgical margins and extraprostatic extension was 44% and 47% respectively. A greater surgical margin compromise and extraprostatic extension was observed when the Gleason score was 8 or higher.