COMPARISON OF THE VALUE BETWEEN COMPUTED TOMOGRAPHY AND MAGNETIC RESONANCE IMAGING IN REASSESSMENT OF THE T-STAGE OF RECTAL CANCER AFTER NEOADJUVANT THERAPY
Main Article Content
Abstract
Background: Staging assessment plays an important role in choosing the optimal treatment method for patients with rectal cancer. Especially in the case of neoadjuvant chemoradiation, this affects the surgical method, for example local or total rectal resection
Objective: Comparing the value of computed tomography and magnetic resonance imaging in predicting local tumor stage (yT), regional lymph node metastasis and Circumferential resection margin (yCRM) after neoadjuvant chemoradiation.
Methods: Cross-sectional study on 62 rectal cancer patients who underwent CT and MRI before and after neoadjuvant chemoradiation with a long course, surgery and pathology results at Ho Chi Minh City University of Medicine and Pharmacy Hospital. The disease stage was reassessment before surgery on CT and MRI, compared with pathology results with a complete description of ypT stage, lymph node metastasis, and ypCRM.
Results: The value of CT and MRI to evaluate non-T0 stages is not different. Both diagnostic tools have high sensitivity, positive predictive value, and accuracy in assessing non-T0 stages. CT and MRI both have high specificity, accuracy and negative predictive value in assessing stage T4 (82 - 94.5%). Regarding overall accuracy, CT is lower than MRI in assessing T stage (38.7 vs. 54.8%). In assessing lymph nodes metastasis, CT and MRI do not have a clear difference in value. Both have quite good negative predictive values, approximately 80%. CT and MRI both have high negative predictive value in assessing mesorectal fascia invasion, approximately 95% and MRI has 11-13% higher specificity and accuracy than CT.
Conclusions: After neoadjuvant therapy, CT and MRI both show good reliability in detecting remaining tumor, so a "watch and wait" strategy can be considered for cases where the tumor is no longer visible. Both have good reliability to exclude stage yT4, regional lymph node metastasis and mesorectal fascia invasion.
Keywords
Rectal cancer, computed tomography and magnetic resonance imaging, neoadjuvant chemoradiation, stage reassessment.
Article Details
References
2. Fernandez LM, São Julião GP, Figueiredo NL. Conditional recurrence-free survival of clinical complete responders managed by watch and wait after neoadjuvant chemoradiotherapy for rectal cancer in the International Watch & Wait Database: a retrospective, international, multicentre registry study. Lancet Oncol. Jan 2021;22(1):43-50. doi:10.1016/s1470-2045(20)30557-x
3. Kalisz KR, Enzerra MD, Paspulati RM. MRI Evaluation of the Response of Rectal Cancer to Neoadjuvant Chemoradiation Therapy. Radiographics. Mar-Apr 2019;39(2):538-556. doi:10.1148/rg.2019180075
4. Glynne-Jones R, Wyrwicz L, Tiret Eea. Rectal cancer: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up. Ann Oncol. Jul 1 2017;28(suppl_4):iv22-iv40. doi:10.1093/annonc/mdx224
5. Weiser MR. AJCC 8th Edition: Colorectal Cancer. Ann Surg Oncol. Jun 2018;25(6):1454-1455. doi:10.1245/ s10434-018-6462-1
6. Burton S, Brown G, Bees N, et al. Accuracy of CT prediction of poor prognostic features in colonic cancer. Br J Radiol. Jan 2008;81(961):10-9. doi:10.1259/bjr/19492531
7. Bogveradze N, Snaebjornsson P, Grotenhuis BAea. MRI anatomy of the rectum: key concepts important for rectal cancer staging and treatment planning. Insights Imaging. Jan 18 2023;14(1):13. doi:10.1186/s13244-022-01348-8
8. Lee S, Kassam Z, Baheti ADea. Rectal cancer lexicon 2023 revised and updated consensus statement from the Society of Abdominal Radiology Colorectal and Anal Cancer Disease-Focused Panel. Abdom Radiol (NY). May 5 2023;doi:10.1007/s00261-023-03893-2
9. Group MS. Diagnostic accuracy of preoperative magnetic resonance imaging in predicting curative resection of rectal cancer: prospective observational study. Bmj. Oct 14 2006;333(7572):779. doi:10.1136/bmj.38937.646400.55
10. Santiago I, Figueiredo N, Parés Oea. MRI of rectal cancer-relevant anatomy and staging key points. Insights Imaging. Sep 3 2020;11(1):100. doi:10.1186/s13244-020-00890-7
11. Ramanan, Munikrishnan, al. Ve. Accuracy of High Resolution Multidetector Computed Tomography in the Local Staging of Rectal Cancer. Journal of Gastrointestinal and Abdominal Radiology. 04/30 2021;05:001-015. doi:10.1055/s-0041-1726662
12. G CMWAaB. Evaluation of Mesorectal Lymph Nodes with High-Resolution MRI. Austin J Cancer Clin Re. 2014;1(4)
13. Park JH, Kim YH, al. SMLe. Diagnostic Accuracy of Computed Tomography and Magnetic Resonance Imaging Obtained after Neoadjuvant Chemoradiotherapy in Predicting the Local Tumor Stage and Circumferential Resection Margin Status of Rectal Cancer. Journal of The Korean Society of Radiology. 2014;70(2):123-132. doi:https://doi. org/10.3348/jksr.2014.70.2.123 14. Pomerri F, Pucciarelli S, Maretto Iea. Prospective assessment of imaging after preoperative chemoradiotherapy for rectal cancer. Surgery. Jan 2011;149(1):56-64. doi:10.1016/j.surg.2010.03.025
15. Liu W, Li Y, Zhang Xea. Preoperative T and N Restaging of Rectal Cancer After Neoadjuvant Chemoradiotherapy: An Accuracy Comparison Between MSCT and MRI. Front Oncol. 2021;11:806749. doi:10.3389/fonc.2021.806749