Immunohistochemical expression of Ki-67 and p53 along with their digitalized evaluation in the discriminatory analysis of reactive atypia and dysplastic lesions in gastrointestinal biopsies of the stomach.

The differential diagnosis between reactive atypia and non-invasive neoplasia (or dysplasia) can be challenging in the case of small conventional forceps biopsy specimens of the stomach. Despite the existence of several classifications for neoplastic epithelial lesions of the stomach, there are few auxiliary tools for aiding in this decision besides standard stains. We studied the utility of Ki-67 and p53 immunohistochemistry in this setting and their clinico-pathological correlations, based on a set of 99 cases with cytological or architectural atypia reviewed by three pathologists. We also tested a digitalized method based on the ImageJ software for the evaluation of Ki-67 expression to determine whether this could be of an additional help. CONCLUSIONS: Ki-67 and p53 expression correlates well with microscopic and morphological modifications in biopsies and can be a useful tool in confirming or dismissing an impression of dysplasia in routine pathological work-up. Digital processing is cumbersome and of limited value and it could only be of additional help if more automated methods are developed.