Abstract

Introduction: Colorectal cancer (CRC) is the third most common cancer diagnosis in men and women in the United States. The sigmoid colon is the most common location for colon cancer, while cancer of the appendix is relatively rare. Although 95% of colorectal carcinomas are adenocarcinomas, the majority of appendiceal cancers are neuroendocrine tumors. The most commonly encountered disease of the appendix is acute inflammation. Appendicitis accounts for nearly 300,000 hospital visits in the United States annually.  Acute appendicitis classically presents as periumbilical pain that subsequently localizes to the right lower quadrant. Here we describe a case that presented as textbook appendicitis, but was found to be metastatic adenocarcinoma of the appendix and right colon.

Case description:  A 61-year-old Hispanic male with a past medical history of diabetes, hypertension, hyperlipidemia, gout and obesity presented to the emergency room with worsening abdominal pain over two days. He initially had periumbilical pain that later intensified and localized to the right lower quadrant. computed tomography (CT) abdomen showed signs of appendicitis including an engorged, fluid filled appendix with wall thickening and associated fat stranding. The patient denied any fevers, chills, headache, chest pain, changes in bowel or bladder habits, or numbness or tingling in extremities.  The patient went for a routine laparoscopic appendectomy. During the procedure, the appendix was noted to be significantly firm and attempts were made to grasp it to allow for better visualization of the appendiceal base. After multiple attempts had failed to mobilize the appendix laparoscopically, the surgeon elected to proceed with an open conversion. The appendix was noted to be larger than initially anticipated as seen during laparoscopy. The firmness and woodiness of the tissue was noted to extend well into the base of the cecum. There was also diffuse mesenteric lymphadenopathy concerning for malignancy. Given these findings, a right hemicolectomy was performed.  The pathology report revealed moderately differentiated metastatic adenocarcinoma. Oncology was brought on board and the carcinoembryonic antigen (CEA) was determined to be 6.8. Patient was discharged with plans for PET scan and portacath for chemotherapy.

Discussion: This case illustrates a rare occurrence of appendiceal adenocarcinoma with metastasis. While colon cancer is very common, only 0.4% of gastrointestinal cancers are of the appendix.  Moreover, only 10 percent of appendiceal tumors are adenocarcinomas. This case demonstrates the importance of having a high index of suspicion for malignancy even given a textbook presentation of a common complaint.