Comparative study of the different degrees of risk of gastrointestinal stromal tumor

Abstract

ABSTRACT ABSTRACT ABSTRACTObjective Objective Objective Objective Objective: To evaluate the applicability of the main categories of risk and morphological factors in the prognosis of gastrointestinal stromal tumors. MethodsMethods Methods Methods Methods: we retrospectively studied fifty-four cases of GIST, assessing the main prognostic factors of this neoplasis: risk levels, topography, size, mitotic index, necrosis, histological subtype and immunophenotype. We also verified their association and the reduction of overall survival. Results Results ResultsResults Results: Univariate analysis showed that tumors with mitoses number greater than 5 per 50CGA (high-power fields), the presence of necrosis and a high risk for both the systems proposed by Fletcher and Miettinen had a significant association with reduced survival (p = 0.00001, 0.0056, 0.03 and 0.009, respectively). The remaining analyzed factors (size, histological subtype, topography and immunophenotype) had no such association. Multivariate analysis (Jacard index) showed that the Miettinen degree of risk was the one that best correlated with prognosis. Conclusion Conclusion Conclusion Conclusion Conclusion: the risk criteria of Fletcher and Miettinen are important in assessing the prognosis of patients with gastrointestinal stromal tumors, especially the latter, which adds to the mitotic index and the presence of tumor necrosis. G astrointestinal stromal tumors (GIST) are the most common mesenchymal neoplasms of the gastrointestinal tract 1 , their incidence being estimated at 14 to 20 cases per million population 2 ; they are more frequent in male patients older than 50 years old 3 . The pathogenesis is related to mutational changes in two tyrosine kinase receptors: KIT and PDGFR-alpha (plateletderived growth factor receptor alpha) on the surface of the interstitial cells of Cajal, the former being the most common (85% of cases) 4,5 . Gastrointestinal stromal tumors can develop in any topography, from the esophagus to the rectum. However, they are more common in the stomach (50% to 60%), followed by small intestine (20% to 30%), colon (10%), rectum or esophagus (5%) 6 . Macroscopically, the tumor lesions often have a nodular form, transmural involvement and submucosal growth, with ulceration of the mucosa or not. In light microscopy, histology reveals three types: the most common spindle (70%), epidermoid (20%) and the mixed type (10%), when there is combination of epithelioid and spindle ones 7 . Key wordsThe diagnosis of stromal neoplasms is based on immunohistochemical study with CD117 marker, expressed in most such neoplasias 1 . Noteworthy are also other markers: DOG 1, nestin, theta protein kinase C and carbonic anhydrase II 8 . The differential diagnosis includes: desmoid tumor, inflammatory myofibroblastomas, leiomyoma, inflammatory fibroid polyp, neuroma, neurossarcoma, sarcomatoid mesothelioma and metastatic melanoma 7,9,10 GIST prognosis is still matter of discussion. Currently there are different classifications 7,[11][12...

Preoperative prediction of gastrointestinal stromal tumors with high Ki-67 proliferation index based on CT features

“…Even if necrosis and its related parameters were not significant indicators for ruptured GISTs according to previous studies (26), they were demonstrated to be significant predictors in high-risk stratification GISTs (24,33,39). Previous studies have also shown that necrosis is one of the pathological predictors of malignant behavior of GISTs and is more important for evaluating the prognosis of GISTs (17,36,(40)(41)(42). It is considered that necrosis is directly related to the severe proliferation of tumor portion; that is, necrosis will occur in the most invasive and aggressive area (42).…”

Tissue microarray technology and collagen evaluation to analyze surgical trauma performed with usual blade or ultrasonic harmonic scalpels in rats

“…It was here applied because less energy is transduced to tissue compared to other devices, and do not pass electricity through the body 5,9 . Another benefit is reduction in analgesics administration in the postoperative period [10][11][12][13][14][15] .…”

Laparoscopic Resection of Gastrointestinal Stromal Tumors (Gist)

“…Among prognostic criteria, mitosis index is the most related to recurrence 2 , 22 . In these authors experience, patient with higher number of mitosis per 50 HPF analysis suffered early disease recurrence.…”