Nuclear morphometry and proliferative activity evaluation in the gastrointestinal stromal tumors

Twenty-two cases with gastrointestinal stromal tumors (GISTs) have been studied, sized from 2 cm to invasive gigantic tumors and also from low to high degree of malignancy. The altering of the form and the size of the nucleus is a reference point of malignancy, being used in the histological grading of many types of tumors and also as an appreciating parameter of the tumoral prognosis, with a high degree of accuracy in the colorectal, uterine, prostatic or ovarian cancers, as it was pointed in the previous researches. The aim of this study is to evaluate the dimensional characteristic of the nuclei and the mitosis in GIST with a cholic and gastric localization, attempting a quantitative differentiation of the two tumors, by studying the following aspects: nuclear dimensions, mitotic activity index and the mitotic density. The results of the proliferative activity quantification (mitotic activity index and mitotic density) have shown that this can be a decisive criterion for the precocious appreciation of the evolution. The most important morphological criterion with a predictive role is the mitotic activity index, but is recommended to be applied correlated with the size and the localization of the tumor. Although various nuclear morphometry studies in different types of malignant tumors have been performed, the data in gastrointestinal stromal tumors is scarce and only few similar studies have been reported in the specialty literature; from this point of view, the present study is new and original and is also trying to point out that even with GIST, such analysis and prognosis is as valuable as in any other malignant diseases.