Young-onset colon adenocarcinoma masquerading as acute appendicitis

This case report presents the findings of colon adenocarcinoma in a young adult male who presented with vague abdominal pain as his only complaint, suspicious of appendicitis. The patient underwent abdominal computed tomography (CT) imaging for further evaluation of his abdominal pain. CT findings showed pericecal fat stranding and prominent lymph nodes concerning for acute appendicitis, but the appendix could not be adequately visualized; due to the indeterminate CT findings, general surgery proceeded to perform an exploratory laparotomy on the patient and removed an appendiceal mass-like structure that was revealed to be invasive adenocarcinoma of the colon per pathology. This case report details the radiological and pathological findings of colorectal adenocarcinoma presenting similarly to acute appendicitis and demonstrates that colorectal adenocarcinoma must be considered on the list of differentials in young adults presenting with abdominal pain and unclear CT imaging.