P-196 - New perspective for detecting advanced colorectal neoplastic lesions by cytogenetic biomarkers in average risk patients

Date 04 July 2015
Event WorldGI 2015
Session Posters
Topics Colon Cancer
Rectal Cancer
Translational Research
Presenter E.M. Ionescu
Citation Annals of Oncology (2015) 26 (suppl_4): 1-100. 10.1093/annonc/mdv233
Authors E.M. Ionescu, T. Nicolaie, A. Ionescu, M. Diculescu, M. Ciocirlan
  • “Carol Davila” University of Medicine and Pharmacy, Bucharest/RO

Abstract

Introduction

Loss of genetic stability seems to be one of the main pathogenic key processes appearing early in carcinogenesis of colorectal carcinomas (CRC). We used the Cytokinesis-Bloked Micronucleus Assay (CBMN) technique for detecting DNA damages. The aim of our study was to predict the presence of significant colorectal lesions by specific biomarkers detected by this method in average risk persons.

Methods

We designed a prospective study including patients undergoing diagnostic or opportunistic screening colonoscopy. A blood sample was obtained from each patient to be analyzed by CBMN technique for specific biomarkers: presence of micronuclei (MN), nucleoplasmic bridges (NPB) and the Nuclear Division Index (NDI).

Results

98 patients met the inclusion criteria, 57 of them assimilated to average-risk persons (age between 50-75 years, with no personal or familial CRC history). The mean age of our group was 55.36. The advanced neoplasia rate was 34.68% for the entire group. In the average-risk group 21.05% had advanced adenoma and 26.31% adenocarcinomas. MN frequency and NPB presence were not significantly different in patients with neoplastic lesions compared to normal population or non-neoplastic colorectal lesions. NDI was significant lower in patients with adenoma or adenocarcinoma versus individuals with normal colonoscopy or non-neoplastic lesions, in the whole group but also in average-risk group (AUC ROC = 0.668, p = 0.005 and AUC ROC = 0.715, p = 0.006 respectively). For a cut-off value of NDI =1.8, the sensitivity in detecting any neoplasia was 97.7% for all patients and 97% for medium-risk patients. NDI was significantly lower in patients with advanced neoplasia compared with individuals with normal colonoscopy or with non significant colorectal lesions (AUC ROC = 0.636, p = 0.029 for all patients, AUC ROC = 0.672, p = 0.029 for average-risk group). For the same cut-off value of NDI of 1.8, the sensitivity in detecting advanced neoplasia was 97% for all patients and 96% for average-risk group. When predicting only carcinomas, an NDI value of < 1.8 will predict it with a sensitivity of 94.4% for all patients and 93.3% for average-risk group.

Conclusion

We found a significantly low Nuclear Division Index in patients with advanced colorectal neoplasia in average risk individuals. NDI score may have a certain value in colorectal cancer screening.