Evaluation of microsatellite instability in colon adenocarcinoma with IHC staining for (MLH1) in patients admitted to hospitals in Kerman during the years 89-93

Introduction: A group of genetic changes can ultimately lead to colorectal carcinoma. The adenoma-carcinoma sequence pattern suggests that there is a high incidence of carcinomain high-prevalence populations, and the risk of cancer is directly related to the number of adenomas, Therefore, definite cancer patients develop familial polyposis syndrome, but theemergence of colorectal cancer without evidence of polyps suggests that some lesions without polypoid stage go to malignancy This pathway is characterized by genetic lesionsin DNA repair mismatch genes and is involved in HNPCC (Non-Polypoid Hereditary Colorectal Cancer) syndrome in 10-15% of cases. Incomplete DNA repair is the mostlikely occurrence of the onset event, given that one of the pathways for the development of colorectal cancer in non-polypoid lesions is microcosmitis instability. In this study,inpatients with colorectal cancer who referred to Kerman hospitals between 1393-1953, we examined the incidence of this instability and its correlation, HNPCC and tumor STAGE.Methods: This descriptive-analytic cross-sectional study was performed on all patients with confirmed adenocarcinoma of the colon and recorded in the Afzalipour hospitals inKerman city by census method. In this research, the blocks of adenocarcinoma of the colon were collected from a state center with patient information (Cancer STAGE, age, sex,location of the lesion and histological type of cancer). The best block was a block of tumor that had tumoral and superficial surfaces and, if possible, had normal tissueof the intestinalwall, was cut again, and the slides were stained with hematoxylin and eosin (H & E) and staining of immunohistochemistry (IHC) were stained for MLH1.Results: Out of 51 subjects, 32 (62.7%) were male and 19 (37.3%) were female. 15 (29.4%) were in the age group of 49-29 years old and 36 (70.6%) were in the age group of82-50 years old. The results of this study showed that there was a significant relationship between MLH1 and tumor stage with pvalue = 112, lymph node involvement with pvalue= 0.318 and tumor location with pvalue = 0.08. Coloring panel with mesinous tumor and mussinose bread with pvalue = 0/001 had a significant relationship. Conclusion: There was a significant statistical relationship between the histological type of tumor and microsatellite instability (P <0.001). In the mucinous type (13 out of 15cases), non-mucosal instability (5 out of 36 Case) was higher. However, there was no significant relationship between the micro-seditol instability with the age and sex of thepatient, Stage and Grade of the tumor and the location of the lesions.

Keywords:

MLH1 , microsatellite instability , colon adenocarcinoma