Genomic Profiling of Small-Bowel Adenocarcinoma.

ABSTRACT:

Importance

Small-bowel adenocarcinomas (SBAs) are rare cancers with a significantly lower incidence, later stage at diagnosis, and worse overall survival than other intestinal-derived cancers. To date, comprehensive genomic analysis of SBA is lacking.

Objective

To perform in-depth genomic characterization of a large series of SBAs and other gastrointestinal tumors to draw comparisons and identify potentially clinically actionable alterations.

Design, setting, and participants

Prospective analysis was performed of clinical samples from patients with SBA (n?=?317), colorectal cancer (n?=?6353), and gastric carcinoma (n?=?889) collected between August 24, 2012, and February 3, 2016, using hybrid-capture-based genomic profiling, at the request of the individual treating physicians in the course of clinical care for the purpose of making therapy decisions.

Results

Of the 7559 patients included in analysis, 4138 (54.7%) were male; the median age was 56 (range, 12-101) years. The frequency of genomic alterations seen in SBA demonstrated distinct differences in comparison with either colorectal cancer (APC: 26.8% [85 of 317] vs 75.9% [4823 of 6353], P?Conclusions and relevanceThis study presents to our knowledge the first large-scale genomic comparison of SBA with colorectal cancer and gastric carcinoma. The distinct genomic differences establish SBA as a molecularly unique intestinal cancer. In addition, genomic profiling can identify potentially targetable genomic alterations in the majority of SBA cases (91%), and the higher incidence of microsatellite instability and tumor mutational burden in SBA suggests a potential role for immunotherapy.

SUBMITTER: Schrock AB 

PROVIDER: S-EPMC5710195 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature