Complete appendiceal intussusception and appendiceal mucinous tumor: A case report and review of literature.

Background: Complete appendiceal intussusception (CAI) coexisting with appendiceal tumor represents an exceptionally rare clinical tumor. This study presented a retrospective analysis of a case involving CAI complicated by appendiceal mucinous tumor, supplemented by a review of 10 previously reported cases to distill diagnostic and therapeutic insights.

Case summary: A 74-year-old male patient presented with abdominal pain. Abdominal contrast-enhanced computed tomography (CECT) initially suggested a colonic tumor with intussusception. Colonoscopy identified a mass in the colon 60 cm from the anus. Intraoperative exploration confirmed CAI secondary to an appendiceal neoplasm. The patient underwent laparoscopic right hemicolectomy with regional lymphadenectomy under general anesthesia. Postoperative recovery was uneventful, and the patient was discharged 9 days post-surgery. Twelve-month follow-up revealed no evidence of recurrence or metastasis.

Conclusion: Plain abdominal computed tomography may underestimate the presence of CAI and appendiceal mucinous tumor, whereas CECT significantly improves diagnostic accuracy. Preoperative suspicion of appendiceal malignancy should be entertained in cases of CAI. In the absence of definitive biopsy results, intraoperative frozen section analysis is recommended to guide radical resection.