pT1 Colorectal Cancer Detected in a Colorectal Cancer Mass Screening Program: Treatment and Factors Associated with Residual and Extraluminal Disease

Abstract

The aim of this study is to describe the treatment of pT1 colorectal cancer (CRC) in a mass screening program, the surgery-related complications and the factors associated with residual disease after endoscopic resection and extraluminal disease after surgery. We included in this retrospective analysis all the pT1 CRC detected in the Galician CRC screening program between May 2013 and June 2019. We determined which variables were independently associated with the outcomes of the study through a multivariable logistic regression analysis. We included 370–354 pT1 N0(X), 16 pT1N1- out of the 971 CRC detected; 277 (74.9%) were resected endoscopically and 162 (43.8%) were not referred to surgery. There were surgical complications in 30.7% and 16.3% of the patients during hospitalization and after discharge. Residual disease was detected in 12 (4.3%) after endoscopic resection and extraluminal disease in 18 (8.6%) patients after surgery. The variables independently associated with initial endoscopic resection were a pedunculated morphology (OR 33.1, 95% CI 4.3–254), a diameter ≥ 20 mm (OR 3.94, 95% CI 1.39–11.18) and a Site–Morphology–Size–Access score < 9 (OR 428, 95% CI 42–4263). The variables related with surgery rescue were a piecemeal resection (OR 4.48, 95% CI 1.48–13.6), an infiltrated/nonevaluable resection border (OR 7.44, 95% CI 2.12–26.0), a non-well-differentiated histology (OR 4.76, 95% CI 1.07–20.0), vascular infiltration (OR 8.24, 95% CI 2.72–25.0) and a Haggitt 4 infiltration of the submucosa (OR 5.68, 95% CI 2.62–12.3). Residual disease after endoscopic resection was associated with an infiltrated/nonevaluable resection border (OR 34.9, 95% CI 4.08–298), a non-well-differentiated histology (OR 6.67, 95% CI 1.05–50.0), and the vascular infiltration of the submucosa (OR 7.61, 95% CI 1.55–37.4). The variables related with extraluminal disease after surgical resection were no endoscopic resection (OR 4.34, 95% CI 1.26–14.28), a non-well-differentiated histology (OR 4.35, 95% CI 1.39–14.29) and the lymphatic infiltration of the submucosa (OR 4.8, 95% CI 1.32–17.8). In a CRC screening program, although most of pT1 CRC are candidates for endoscopic treatment, surgery is a safe procedure. We have defined some easy to evaluate variables that can be used in the decision-making process.

Endoscopic submucosal dissection for superficial gastrointestinal lesions: European Society of Gastrointestinal Endoscopy (ESGE) Guideline – Update 2022

“…In a recent study evaluating risk factors for an adverse prognosis after ER of T1 tumors, the variables related to surgical rescue were piecemeal resection (OR 4.48, 95 %CI 1.48–13.6), infiltrated/nonevaluable resection border (OR 7.44, 95 %CI 2.12–26.0), not well-differentiated histology (OR 4.76, 95 %CI 1.07–20.0), vascular infiltration (OR 8.24, 95 %CI 2.72–25.0), and Haggitt 4 infiltration of the submucosa (OR 5.68, 95 %CI 2.62–12.3). Residual disease after ER was associated with infiltrated/non-evaluable resection border (OR 34.9, 95 %CI 4.08–298), not well-differentiated histology (OR 6.67, 95 %CI 1.05–50.0), and vascular infiltration of the submucosa (OR 7.61, 95 %CI 1.55–37.4) 208 . So, clearly a positive vertical margin is a risk factor for residual disease and need for additional surgery and potential for LNM, as suggested by the study of Boenicke et al This showed that in patients who underwent ER of malignant polyps followed by surgery, even though 63 % of resection margins were positive (a free margin was not defined as a tumor-free extent of more than 1 mm), subsequent surgical specimens showed residual carcinoma in only 2.8 % but LNM in 7.6 % 209 .…”

“…In a recent study evaluating risk factors for an adverse prognosis after ER of T1 tumors, the variables related to surgical rescue were piecemeal resection (OR 4.48, 95 %CI 1. 48 [208]. So, clearly a positive vertical margin is a risk factor for residual disease and need for additional surgery and potential for LNM, as suggested by the study of Boenicke et al This showed that in patients who underwent ER of malignant polyps followed by surgery, even though 63 % of resection margins were positive (a free margin was not defined as a tumor-free extent of more than 1 mm), subsequent surgical specimens showed residual carcinoma in only 2.8 % but LNM in 7.6 % [209].…”

Real-time polyp detection model using convolutional neural networks

“…These images were annotated by a team of experienced endoscopists (JC, JH, MP, DR, LR, and ES) with the locations of the polyps (bounding boxes). All the endoscopists participated in the Galician CRC screening program [67]. The median number of colonoscopies performed annually by the endoscopists enrolled in the screening program (71 from 7 hospitals) was 278 (IQR 56-507) and the median adenoma detection rate was 65.3% (IQR 60.0-70.1%).…”

Overtreatment in nonmalignant lesions detected in a colorectal cancer screening program: a retrospective cohort study

“…Galician CRC mass screening and its implementation have been described elsewhere [13]. The CRC screening program includes the central coordination and management of patient follow-up after polyp resection depending on their risk according to EU guidelines for quality assurance on CRC screening recommendations [14].…”