Comparative prognostic value of ultrasound and CT scan in postoperative follow-up of colorectal cancer

This retrospective comparative study aimed to evaluate and compare the prognostic assessment value of ultrasound and CT scans in post-operative follow-up of colorectal cancer patients. A retrospective analysis of colorectal cancer patients who underwent radical surgery between January 2022 and December 2023. The ultrasound follow-up group included 103 patients, while the CT scan follow-up group comprised 95 patients. Imaging follow-up was performed at 6, 12, and 24 months post-surgery. Primary outcomes included local recurrence rates, distant metastasis detection rates, prognostic prediction accuracy, and the sensitivity and specificity of both imaging methods. Among 198 patients, local recurrence rates were 14.6% (29/198) in the ultrasound group and 16.2% (32/198) in the CT scan group, with no statistically significant difference (P=0.62). Distant metastasis detection rates were 10.1% (20/198) for ultrasound and 13.1% (26/198) for CT scans, also showing no significant statistical difference (P=0.34). The positive predictive value for prognosis was 78.3% for ultrasound and 82.5% for CT scans. Ultrasound showed lower sensitivity (65.4%) for lesions smaller than 2cm, while CT scans demonstrated significantly higher detection rates for small lesions (82.7%, P<0.01). CT scans showed slightly superior performance in post-operative prognostic assessment of colorectal cancer, particularly in detecting small lesions.