Novel Methods of Risk Stratifying Patients for Metachronous, Pre-Malignant Colorectal Polyps: A Systematic Review

INTRODUCTION

Despite conventional measures of future polyp risk (histology, dysplasia, size, number), surveillance places a burden on patients and colonoscopy services. We aimed to review novel risk stratification techniques.

METHODS

A systematic literature review was performed for studies using genomics, transcriptomics, IHC or microbiome as markers of metachronous polyp risk.

RESULTS

4165 papers underwent title, 303 abstract and 215 full paper review. 25 papers were included. 49 mutations/ SNPs/ haplotypes in 23 genes/ chromosomal regions (KRAS, APC, EGFR, COX1/2, IL23R, DRD2, CYP2C9/24A1/7A1, UGT1A6, ODC, ALOX12/15, PGDH, SRC, IGSF5, KCNS3, EPHB1/ KY, FAM188b, 3p24.1, 9q33.2, 13q33.2) correlated with metachronous adenoma / advanced adenoma risk. Expression levels of 6 proteins correlated with metachronous adenoma (p53, β-catenin, COX2, Adnab-9, ALDH1A1) or sessile serrated polyp (ANXA10) risk.

CONCLUSION

Although genomic and IHC markers correlated with metachronous polyp risk, it seems likely that a panel of novel markers will be required to refine this risk.

The Prognostic Significance of c-Met and p53 Immunohistochemical Expression in Gastric and Colorectal Carcinomas

BACKGROUND: Colorectal and gastric carcinomas are the most common and deadly gastrointestinal (GIT) malignancies. AIM: This study aimed to evaluate the expression of c-Met and p53 in gastric and colorectal carcinomas (CRCs) as well as colorectal adenomas using immunohistochemistry. MATERIALS AND METHODS: c-Met and p53 immunohistochemical expression was conducted on 66 cases of gastric adenocarcinomas and total of 60 colonic cases (36 CRCs and 24 colorectal adenomas). RESULTS: In this study, c-Met was positively expressed in 54.5% of gastric carcinomas and 50% of CRCs. In addition, p53 was positively expressed in 56.1% of gastric carcinomas and 72.2% of CRCs. Moreover, higher expression of both c-Met (p = 0.001) and p53 expression (p < 0.001) was reported in CRCs compared to colorectal adenomas. In the same context, c-Met and p53 expressions were positively correlated with intestinal type gastric adenocarcinoma (p < 0.001 and p = 0.03, respectively). Moreover, c-Met was correlated with non-mucinous adenocarcinomas (p = 0.008) and lower grades (p < 0.001) of gastric carcinomas. As regard survival analysis in gastric carcinomas, median overall survival (OS) was better in p53 positive patients (p = 0.05), patients with negative lymph node metastasis (p = 0.03), and patients with better response to neoadjuvant chemotherapy (p = 0.04). In contrast, c-Met did not exhibit significant correlation with OS (p > 0.05). Both c-Met and p53 did not reveal significant correlation with tumor stage and site in both CRCs and gastric carcinomas (p > 0.05). CONCLUSION: We concluded that c-Met and p53 are expressed in the most common GIT malignancies addressing them as potential biomarkers. In addition, c- Met and p53 may have a potential role in colorectal cancer development as they showed higher positivity in CRCs compared to adenomas.

Ki-67 and Bcl-2 antigen expression in adenomatous colorectal polyps from women with breast cancer

BACKGROUND

The aim of this study was to evaluate Ki-67 and Bcl-2 antigen expression in colorectal polyps from women with breast cancer.

METHODS

A randomized, controlled study was carried out in 35 women, either with or without breast cancer, who had adenomatous colorectal polyps. The patients were divided into two groups: group A (without breast cancer; control group; n = 17) and group B (with breast cancer; study group; n = 18). Immunohistochemistry was performed on the colorectal polyps to evaluate Ki-67 and Bcl-2 antigen expression. Student's t-test and the chi(2) test were used for the statistical analysis of Ki-67 and Bcl-2 expression, respectively. Statistical significance was established as P < 0.05.

RESULTS

The mean percentage of Ki-67-stained nuclei in groups A and B was 36.25 +/- 2.31 and 59.44 +/- 3.34 (+/- SEM), respectively (P < 0.0001), while the percentage of cases with cells expressing Bcl-2 in groups A and B was 23.5 and 77.8%, respectively (P < 0.001).

CONCLUSIONS

In the present study, there was greater proliferative activity and greater expression of the antiapoptotic protein Bcl-2 in the colorectal polyps of women with breast cancer.