TY - JOUR
T1 - The sigmoid take-off as a landmark to distinguish rectal from sigmoid tumours on MRI
T2 - Reproducibility, pitfalls and potential impact on treatment stratification
AU - Bogveradze, Nino
AU - Lambregts, Doenja M. J.
AU - el Khababi, Najim
AU - Dresen, Raphaëla C.
AU - Maas, Monique
AU - Kusters, Miranda
AU - Tanis, Pieter J.
AU - Beets-Tan, Regina G. H.
AU - Alberts, Femke
AU - Bakers, Frans C. H.
AU - Batiashvili, Nino
AU - Beets, Geerard L.
AU - de Bie, Shira
AU - Bosma, Gerlof
AU - Cappendijk, Vincent C.
AU - Castagnoli, Francesca
AU - Daushvili, Ana
AU - Doornebosch, Pascal
AU - Geenen, Remy
AU - Grotenhuis, Brechtje
AU - Jokharidze, Tedo
AU - Lahaye, Max J.
AU - Landolfi, Federica
AU - Leeuwenburgh, Marjolein
AU - Neijenhuis, Peter
AU - Peterson, Gerald
AU - Steller, Ernst J. A.
AU - Veeken, Cornelis J.
AU - de Vuysere, Sofie
AU - Vermaas, Maarten
AU - Vliegen, Roy F. A.
AU - MRI rectal study group
AU - Wolthuis, Albert
N1 - Publisher Copyright: © 2021 Elsevier Ltd, BASO ~ The Association for Cancer Surgery, and the European Society of Surgical Oncology
PY - 2021
Y1 - 2021
N2 - Purpose: The sigmoid take-off (STO) was recently introduced as a preferred landmark, agreed upon by expert consensus recommendation, to discern rectal from sigmoid cancer on imaging. Aim of this study was to assess the reproducibility of the STO, explore its potential treatment impact and identify its main interpretation pitfalls. Methods: Eleven international radiologists (with varying expertise) retrospectively assessed n = 155 patients with previously clinically staged upper rectal/rectosigmoid tumours and re-classified them using the STO as completely below (rectum), straddling the STO (rectosigmoid) or completely above (sigmoid), after which scores were dichotomized as rectum (below/straddling STO) and sigmoid (above STO), being the clinically most relevant distinction. A random subset of n = 48 was assessed likewise by 6 colorectal surgeons. Results: Interobserver agreement (IOA) for the 3-category score ranged from κ0.19–0.82 (radiologists) and κ0.32–0.72 (surgeons), with highest scores for the most experienced radiologists (κ0.69–0.76). Of the 155 cases, 44 (28%) were re-classified by ≥ 80% of radiologists as sigmoid cancers; 36 of these originally received neoadjuvant treatment which in retrospect might have been omitted if the STO had been applied. Main interpretation pitfalls were related to anatomical variations, borderline cases near the STO and angulation of axial imaging planes. Conclusions: Good agreement was reached for experienced radiologists. Despite considerable variation among less-expert readers, use of the STO could have changed treatment in ±1/4 of patients in our cohort. Identified interpretation pitfalls may serve as a basis for teaching and to further optimize MR protocols.
AB - Purpose: The sigmoid take-off (STO) was recently introduced as a preferred landmark, agreed upon by expert consensus recommendation, to discern rectal from sigmoid cancer on imaging. Aim of this study was to assess the reproducibility of the STO, explore its potential treatment impact and identify its main interpretation pitfalls. Methods: Eleven international radiologists (with varying expertise) retrospectively assessed n = 155 patients with previously clinically staged upper rectal/rectosigmoid tumours and re-classified them using the STO as completely below (rectum), straddling the STO (rectosigmoid) or completely above (sigmoid), after which scores were dichotomized as rectum (below/straddling STO) and sigmoid (above STO), being the clinically most relevant distinction. A random subset of n = 48 was assessed likewise by 6 colorectal surgeons. Results: Interobserver agreement (IOA) for the 3-category score ranged from κ0.19–0.82 (radiologists) and κ0.32–0.72 (surgeons), with highest scores for the most experienced radiologists (κ0.69–0.76). Of the 155 cases, 44 (28%) were re-classified by ≥ 80% of radiologists as sigmoid cancers; 36 of these originally received neoadjuvant treatment which in retrospect might have been omitted if the STO had been applied. Main interpretation pitfalls were related to anatomical variations, borderline cases near the STO and angulation of axial imaging planes. Conclusions: Good agreement was reached for experienced radiologists. Despite considerable variation among less-expert readers, use of the STO could have changed treatment in ±1/4 of patients in our cohort. Identified interpretation pitfalls may serve as a basis for teaching and to further optimize MR protocols.
KW - MRI
KW - Rectal cancer
KW - Sigmoid cancer
KW - Sigmoid take-off
UR - http://www.scopus.com/inward/record.url?scp=85115919497&partnerID=8YFLogxK
U2 - https://doi.org/10.1016/j.ejso.2021.09.009
DO - https://doi.org/10.1016/j.ejso.2021.09.009
M3 - Article
C2 - 34583878
SN - 0748-7983
JO - European Journal of Surgical Oncology
JF - European Journal of Surgical Oncology
ER -