Gastrointestinal mesenchymal tumors - immunophenotypic classification and survival analysis.

摘要: The current definition of gastrointestinal tumors (GIST) as CD117-positive mesenchymal uncertain malignant potential fails to include a number cases with similar histology. In an attempt improve the classification these neoplasms, we conducted immunohistochemical analysis 244 histological features GIST. According their immunophenotype, were classified GISTs, which are characterized by CD117 (c-kit) expression; CD117-negative CD34 positive stromal (GINST); α-smooth muscle actin and/or desmin leiomyogenic (GILT); S-100 and glial fibrillary acidic protein glial/schwannian (GIGT); neuronal/glial (GINT), for S-100/glial plus markers; fibrous (GIFT), only vimentin positive. most common type GIST, followed in order frequency GINST, GILT, GIGT, GIFT, GINT. GISTs did not show any preferential location, whereas GINSTs occurred almost exclusively stomach duodenum, GILTs preferentially large intestine. Over median follow-up period 71 months, behavior, i.e., metastatic spread, was observed all tumor types except GINTs. Malignancy associated distal gut high mitotic activity, size, nuclear pleomorphism, though none criteria alone discriminated between benign malignant. Kaplan-Meier disease-specific survival showed significant differences long-term outcome newly defined subgroups. We conclude that, despite strong morphological similarities, heterogeneous immunophenotype biology.