Impacto do estudo imuno-histoquímico no estadiamento das neoplasias precoces do trato gastrointestinal submetidas à Dissecção Endoscópica da Submucosa (DES)

Abstract

Introduction: Recently, it has been proposed the study of prognostic factors in malignant neoplasms of the gastrointestinal tract (GIT) submitted to endoscopic submucosal dissection (ESD) investigated by immunohistochemical studies, such as lymphatic (D2-40) and blood vascular invasion (CD 34), overexpression of Her-2/neu protein and measurement of proliferative activity by immunohistochemical staining of Ki 67. Objective: Our objective was to determine the role of immunohistochemical study in the staging of specimens of endoscopic submucosal dissection: analysis comparing the detection of BVI and LVI , the HE and immunohistochemistry (IHC) with dialing D2-40 and CD34 in a series of DES products, with cell proliferation by Ki 67 labeling and Her-2/neu protein overexpression, and correlate them with other prognostic factors. Material and Methods: The study was performed IHC in serial sections, using markers D2-40 (lymphatic endothelium) and CD34 (pan-endothelial) in 30 consecutive cases of DES products with histological diagnosis of carcinoma to assess the presence of LVI and BVI . We also used markers Ki 67 (cell proliferation) and Her-2/neu. The results obtained by the analysis were compared with IHC detection of LVI and BVI by HE, and correlated with other prognostic factors, as well as the rate of cell proliferation and overexpression of Her-2/neu. Results: Detection of LVI was considerably higher than that of IVS. The presence of IVL was detected in 6/30 cases (20%) and by HE in 9/30 cases (30%) by IHC. Of the 6 cases with LVI HE, 3 were false positives at IHC. The LVI IHC detected 6 cases that were considered negative for HE. The BVI was observed in 5/30 cases (16.7%) by HE and IHC in only 1 case (3.3%). Were identified by analyzing the IHC, 5 false-positive and 1 false-negative for IVS. The comparison between the detection of LVI and BVI by both methods showed no significant difference. The diagnostic agreement between methods was weak for LVI (Kappa = 0.211) and poor for BVI (Kappa = 0.167). The clinicopathological factors related to the presence of LVI was the depth of tumor layers m1 (p = 0.031) and m3 (p = 0.047). In contrast, all other variables showed no correlation with the presence of IVS. When analyzing the rate of cell proliferation detected by immunohistochemical examination (Ki 67), we did not identify a statistically significant relationship with the variables analyzed. All cases proved negative for overexpression of Her-2/neu protein. Conclusion: Our results indicated that the histopathological analysis of DES products exclusively performing routine HE staining, as usually happens, does not allow the proper evaluation of the presence of LVI or BVI. This study helped to extend and refine the established protocol as proposing the inclusion of immunohistochemical studies researching for BVI and LVI (CD34 and D2-40), cell proliferation (Ki 67) and Her-2/neu overexpression of the protein. This way is submitted, all information currently possible that could be extracted from the product DES improving the staging of the neoplasm.