Inflammatory fibroid polyp: an immunohistochemical study

• Autor(a) principal: Santos, Gilda Da Cunha [UNIFESP]
• Data de Publicação: 2004
• Outros Autores: Alves, Venâncio A.f., Wakamatsu, Alda, Zucoloto, Sérgio
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UNIFESP
• Texto Completo: http://dx.doi.org/10.1590/S0004-28032004000200007; http://repositorio.unifesp.br/handle/11600/2144
• topic: Polyps; Immunohistochemistry; Gastric mucosa; Gastrointestinal diseases; Pólipos; Imunoistoquímica; Mucosa gástrica; Gastroenteropatias

BACKGROUND: Inflammatory fibroid polyp is a localized lesion, which arises in the submucosa of the gastrointestinal tract, most often in the stomach.Although it is generally believed to represent a reactive, nonneoplastic condition, its histogenesis remains controversial. AIM: To study inflammatory fibroid polyp by immunohistochemistry in an attempt to further clarify their histogenesis. MATERIAL AND METHODS: Nine cases were studied by immunohistochemistry using a panel of antibodies against smooth-muscle actin, vimentin, S-100 protein, factor VIII- R.Ag and macrophage (HAM-56). RESULTS: There was a strong diffuse positive staining pattern in the spindle cells with vimentin antibody. A patchy staining for smooth-muscle actin was observed in these cells. Immunophenotyping revealed a heterogeneous reaction with HAM-56. In edematous areas, HAM-56-positive cells show voluminous cytoplasm and reniform nuclei. In cell-rich areas, the HAM-56-positive cells had fusiform cytoplasm. Stains for S-100 and factor VIII RAg were negative in the proliferating elements. CONCLUSIONS: The present immunohistochemical study refutes the suggested neural or vascular nature of the lesion. The strong positivity for vimentin in all cases suggests a major component of spindle cells best recognizable as fibroblasts. These results would favor the existence of a span of morphological and immunohistochemical patterns possibly indicating evolutive phases of an inflammatory reaction.