Introduction: Mesenchymal neoplasms of Gastrointestinal tract are a group of rare tumors with overlapping histological features. Characterization and accurate diagnosis of specific tumors is mandatory since many of these tumors have specific targeted therapy

Aim: Characterization of specific tumor types in mesenchymal tumors of GIT, based on morphology and immunohistochemistry

Materials and methods: 33 cases of mesenchymal tumors of GIT were included in the study presented in a period of 5 years (January 2010-December 2010). Immunohistochemistry was done in all the 33 cases with the markers CD 117, DOG-1, SMA, Vimentin, Desmin and S-100.

Results and Conclusion: Of the 33 cases, 24 (72.72%) were gastrointestinal stromal tumor. The cells were positive for CD 117 and DOG-1. Other markers were negative. Leiomyogenic tumors accounted for 21.21% (7 cases) which included leiomyoma and leiomyosarcoma. They were positive for SMA, Desmin and / or Vimentin. They were negative for other markers. 6.06% (2 cases) were neurogenic which were positive for only S-100.

The role of Immunohistochemistry in the specific diagnosis of mesenchymal tumors of GIT is much significant. The specific treatment and prognosis depends on accurate diagnosis.

Keywords: Mesenchymal tumors, Gastrointestinal stromal tumor, Immunohistochemistry.

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Dr Sunitha Balakrishnan

Associate Professor, Department of Pathology,

Government Medical College, Kottayam, Kerala

Phone: 9446425364, Email: This email address is being protected from spambots. You need JavaScript enabled to view it.