Colon cancer CT staging according to mismatch repair status: Comparison and suggestion of imaging features for high-risk colon cancer. (October 2022)

• Record Type: Journal Article
• Authors: Hong, Eun Kyoung; Chalabi, Myriam; Landolfi, Federica; Castagnoli, Francesca; Park, Sae Jin; Sikorska, Karolina; Aalbers, Arend; van den Berg, Jose; van Leerdam, Monique; Lee, Jeong Min; Beets-Tan, Regina
• Is Part Of: European journal of cancer. Volume 174(2022)
• Page Start: 165
• Page End: 175
• Publication Date: 2022-10
• Subjects: Microsatellite instability -- Colorectal cancer -- Radiologic staging -- Pathologic assessment; Cancer -- Periodicals; Neoplasms -- Periodicals; Cancer -- Périodiques; Cancer; Tumors; Electronic journals; Periodicals; Electronic journals; 616.994
• DOI: 10.1016/j.ejca.2022.06.060
• Languages: English
• ISSNs: 0959-8049

Abstract

Abstract: Background: Neoadjuvant treatment with either chemotherapy or immunotherapy is gaining momentum in colon cancers (CC). To reduce over-treatment, increasing staging accuracy using computed tomography (CT) is of high importance. Purpose: To assess and compare CT imaging features of CC between mismatch repair-proficient (pMMR) and MMR-deficient (dMMR) tumours and identify CT features that can distinguish high-risk (pT3-4, N+) CC according to MMR status. Methods: Primary staging CTs of 266 patients who underwent primary surgical resection of a colon tumour were retrospectively and independently evaluated by two radiologists. Logistic regression analysis was performed to identify significant associations between imaging features and positive lymph node status. Receiver operating characteristic (ROC) curves of significantly associated features were assessed and validated in an external cohort of 104 patients. Results: Among pT3 tumours only, dMMR CC were significantly larger than pMMR CC in both length and thickness (length 59.39 ± 26.28 mm versus 48.70 ± 23.72, respectively, p = 0.031; thickness 20.54 mm ± 11.17 versus 16.34 ± 8.73, respectively, p = 0.027). For pMMR tumours, nodal internal heterogeneity on CT was significantly associated with a positive lymph node status (odds ratio (OR) = 2.66, p = 0.027), while for dMMR tumours, the largest short diameter of the nodes was associated with lymph node status (OR = 2.01, p = 0.049). The best cut-off value of the largest short diameter of involved nodes was 10.4 mm for dMMR and 7.95 mm for pMMR. In the external validation cohort, AUCs for predicting involved nodes based on the largest short diameter was 0.764 for dMMR tumours using 10 mm size cut-off and 0.624 for pMMR tumours using 7 mm cut-off. Conclusion: These data show that CT imaging features of primary CC differ between dMMR and pMMR tumours, suggesting that the assessment of CT-based CC staging should take MMR status into consideration, especially for lymph node status, and thus may help in selecting patients for neoadjuvant treatment. Highlights: Radiologic assessment of colon cancer stage differs between dMMR and pMMR tumours. pMMR tumours: nodal internal heterogeneity is associated with positive lymph nodes. dMMR tumours: diameter of lymph nodes is associated with positive lymph nodes.