Abstract
PurposeThe gastrointestinal tract is home to a wide variety of neoplasms. Gastrointestinal adenocarcinomas display distinct prognostic patterns. With the advent of next generation sequencing, attempts are being made to delineate distinct molecular characteristics of these adenocarcinomas from adjoining anatomical sites. MethodsThirty-seven cases of upper gastrointestinal adenocarcinomas including those of the esophagus, gastroesophageal junction, stomach, small intestine and gallbladder were retrieved. Next generation sequencing data consisting of base substitutions, copy number variations, indels and rearrangements, in 324 genes, were analyzed for recurrent genetic abnormalities. Statistical analysis was performed using IBM SPSS25 and SAS software. ResultsGenetic alterations were found in 181 genes. APC mutations were found in 50% of the esophageal adenocarcinomas, 5% of the gastric adenocarcinomas and 33.3% of the small intestinal adenocarcinomas (p = 0.04). PIK3 gene family mutations were found in 10% of the gastric adenocarcinomas, 66% of the gall bladder adenocarcinomas and 66% of the small intestinal adenocarcinomas (p = 0.002). The mutations were found exclusively in the PIK3 class 1 family. TP53 mutations were more common in tumors with intact DNA mismatch repair protein expression as assessed by immunohistochemistry (p = 0.042). ConclusionIn this study, APC gene mutations were found to be more frequent in esophageal and small intestinal adenocarcinomas than previously reported. PIK3 class 1 gene family mutations were found to be more frequent in gallbladder and small intestinal adenocarcinomas. An inverse relationship was found between TP53 mutations and loss of DNA mismatch repair protein expression.
Highlights
The gastrointestinal tract is home to a wide variety of vastly different, diagnostically challenging neoplasms.[1]
adenomatous polyposis coli (APC) mutations were found in 50% of the esophageal adenocarcinomas, 5% of the gastric adenocarcinomas and 33.3% of the small intestinal adenocarcinomas (p=0.04)
PIK3 gene family mutations were found in 10% of the gastric adenocarcinomas, 66% of the gall bladder adenocarcinomas and 66% of the small intestinal adenocarcinomas (p=0.002).The mutations were found exclusively in the PIK3 class 1 family
Summary
The gastrointestinal tract is home to a wide variety of vastly different, diagnostically challenging neoplasms.[1]. When taken as a whole, adenocarcinomas of the gastrointestinal tract are one of the most common malignancies in the world.[2]. Though they share morphological similarities, these gastrointestinal adenocarcinomas display distinct clinical characteristics in terms of different risk factors and discrete prognostic patterns.[3–5]. Owing to their morphological heterogeneity, the adenocarcinomas of the gastrointestinal tract are difficult to profile based on location.[5,6]. Over the past two decades, immunohistochemistry has evolved and has been routinely incorporated into the workup and assessment of adenocarcinomas of the gastrointestinal tract.[5]. Attempts have been made to utilize immunohistochemical profiles for determining various tumor characteristics including the origin of a malignancy in the setting of widely metastatic disease.[5,6]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
