# Diagnostic Benefits and Surgical Implications of Methods for Tumor Localization in Sigmoid and Rectum Tumors

## TL;DR

This study compares the accuracy of imaging methods for locating tumors in the sigmoid and rectum, finding that retro CT is most accurate and suggesting improvements are needed.

## Contribution

The study provides a comparative analysis of diagnostic accuracy for tumor localization in specific colorectal regions using colonoscopy and CT scans.

## Key findings

- Retro CT showed the highest accuracy (87.5%) for tumor localization compared to colonoscopy (80.0%) and preoperative CT (65.0%).
- Sensitivity varied by tumor location, with retro CT showing higher sensitivity in rectosigmoid and rectal tumors.
- Incorrect tumor localization led to changes in treatment plans, emphasizing the need for improved diagnostic accuracy.

## Abstract

(1) Background: In our study, we aimed to determine the accuracy rates of imaging methods for sigmoid, rectosigmoid colon, and rectum cancer. (2) Methods: Patients with tumors located in the rectosigmoid colon, sigmoid colon, and rectum who were operated on were included. Upon admission, we examined the patients’ first diagnostic colonoscopies and their preoperative repeat control colonoscopies and computed tomography (CT) report. (3) Results: In this study, 23 patients (57.5%) were male. The overall accuracy rates were 80.0% (32/40) in colonoscopy, 65.0% (26/40) in preoperative CT, and 87.5% (35/40) in retro CT, and the differences among the examination methods were statistically significant (p = 0.049). The sensitivity levels decreased to 50.0% for colonoscopy and preoperative CT and 75.0% for retro CT in rectosigmoid colon tumors. In rectal tumors, the sensitivity levels were 75.0% in colonoscopy, 60.0% in preoperative CT, and 80.0% in retro CT. In two patients, the tumor location was given incorrectly, and postoperative pathological evaluations indicated T3N0 tumors; the initially planned treatment was thus changed to include radiotherapy in addition to chemotherapy in the postoperative period because the tumor was located in the middle rectum. (4) Conclusions: Accuracy in tumor localization in sigmoid, rectosigmoid, and rectum tumors still needs to be improved, which could be accomplished with prospective studies. CT evaluations for cancer localization in this patient group should be re-evaluated by a radiologist.