ĐẶC ĐIỂM HÌNH ẢNH CỘNG HƯỞNG TỪ UNG THƯ TRỰC TRÀNG XÂM LẤN MẠC TREO TRỰC TRÀNG

Abstract

Objective: To describe the magnetic resonance imaging (MRI) characteristics of rectal cancer with mesorectal fascia invasion. Material and Methods: This was a retrospective descriptive case series. A total of 62 patients with pathologically confirmed rectal cancer (stage T3 or higher) who underwent preoperative MRI were included. All patients were treated at Binh Dan Hospital from March 2024 to October 2025. Results: The mean age of the study population was 61.9 ± 11.6 years; the proportions of patients aged 50–59, 60–69, and >69 years were similar (29% each). Males accounted for the majority (69.4%). Tumors located in the lower third of the rectum were most common (48.4%), whereas those in the upper third were least frequent (4.8%). The mean tumor thickness was 18.8 ± 8 mm and the mean length was 46.9 ± 14.3 mm. On T2-weighted images, most tumors showed intermediate signal intensity (91.9%), with no cases of high signal intensity. Type 3 enhancement curves (rapid enhancement and washout) were most frequent (64.5%). All tumors demonstrated diffusion restriction, with a mean ADC value of 832.5 ± 126.3 × 10⁻⁶ mm²/s. The mean distance from the outer tumor margin to the mesorectal fascia was 6.3 ± 7.9 mm in T3 tumors and 5.2 ± 5.5 mm in T4 tumors. Histopathology revealed that adenocarcinoma accounted for 91.9% of cases. Conclusion: MRI is a highly accurate imaging modality for assessing mesorectal invasion prior to total mesorectal excision (TME), aiding surgeons in patient stratification and treatment planning based on precise staging.