Carcinoma colorrectal serrado. Descripción histopatológica, inmunohistoquímica y molecular de un caso
Resumen El adenocarcinoma serrado es una variante del carcinoma colorrectal recientemente tipificada, y es el punto final de una via molecular denominada «via serrada». La lesion precursora en esta via es la mutacion del gen BRAF, que origina lesiones serradas con predisposicion a la metilacion genica y a la inestabilidad de microsatelites. En el presente estudio describimos un caso de adenocarcinoma de colon ascendente, con criterios histologicos compatibles con adenocarcinoma serrado: epitelio serrado, citoplasma amplio, nucleo vesicular y ausencia de necrosis. En el estudio inmunohistoquimico se observo perdida de la expresion del gen MLH1. El estudio molecular revelo altos niveles de in…
Intrasinusoidal HHV8-EBV–Positive Large B-Cell Lymphoma With Features of Germinotropic Lymphoproliferative Disorder
Germinotropic lymphoproliferative disorder (GLPD) is a poorly characterized lymphoproliferative entity, recently included in the World Health Organization classification of hematolymphoid neoplasms. The histological pattern of this disease comprises monotypic plasmablasts that involve the germinal centers of the lymphoid follicles (germinotrophism), forming confluent aggregates positive for both human herpes virus type 8 (HHV8) and Epstein-Barr virus. Currently, after 17 years of its first description, only 18 cases have been reported. In this article, we describe a case of a GLPD presenting in an immunocompetent 79-year-old woman with localized axillary lymphadenopathy, showing a prominen…
The Amount of Melanin Influences p16 Loss in Spitzoid Melanocytic Lesions: Correlation With CDKN2A Status by FISH and MLPA.
AIMS The risk assessment of spitzoid lesions is one of the most difficult challenges in dermatopathology practice. In this regard, the loss of p16 expression and the homozygous deletion of CDKN2A, have been pointed in the literature as reliable indicators of high risk. However, these findings are poorly reproducible, and the molecular bases underlying the loss of p16 expression remain unclear. We aimed to identify the underlying events causing loss of CDKN2A/p16 in spitzoid tumors. MATERIALS AND METHODS We evaluated the immunohistochemical expression of p16, and the presence of CDKN2A genetic alterations detected through fluorescence in situ hybridization (FISH) and multiplex ligation-depen…
Desmoplastic primitive nonneural granular cell tumor of the skin.
Abstract Primitive nonneural granular cell tumor of the skin was first described by LeBoit et al in 1991 as "primitive polypoid granular cell tumor." Few cases have been reported to date, all being polypoid or deep well-delimited lesions and formed by large spindle or polygonal granular cells with moderate nuclear atypia and increased mitotic activity. This granular cell population does not have a Schwannian, myogenic, melanocytic, fibroblastic, histiocytic, or epithelial differentiation. We report a case that fully satisfies the criteria for primitive nonneural granular cell tumor of the skin and, in addition, shows an extensive desmoplastic stroma. This desmoplastic variant of primitive n…
Anatomía Patológica para el estudiante de Medicina: videotutoriales con integración de Patología digital como una valiosa herramienta para hacer la asignatura más práctica y atractiva
Resumen Introduccion y objetivo La asignatura de Anatomia Patologica es fundamental en la formacion del estudiante de Medicina. Sin embargo, para muchos estudiantes la asignatura presenta un excesivo contenido teorico, poco trasladable a la practica clinica. Presentamos los resultados de un proyecto de innovacion docente dirigido a facilitar la transmision del conocimiento a distancia y hacer de la Anatomia Patologica una asignatura mas practica y atractiva para el estudiante de Medicina. Materiales y metodos Elaboramos material didactico integrando imagenes de enfermedad digital con videotutoriales para la exposicion de casos clinicos donde los alumnos debian llegar al diagnostico final. C…