Management of non-curative endoscopic resection of T1 colon cancer.

Endoscopic resection techniques enable en-bloc resection of T1 colon cancers. A complete removal of T1 colon cancer can be considered curative when histologic examination of the specimens shows none of the high-risk factors for lymph nodes metastases. Criteria predicting lymph nodes metastases include deep submucosal invasion, poor differentiation, lymphovascular invasion, and high-grade tumor budding. In these cases, complete (R0), local endoscopic resection is considered sufficient as negligible risk of lymph nodes metastases does not outweigh morbidity and mortality associated with surgical resection. Challenges arise when endoscopic resection is incomplete (RX/R1) or high-risk histological features are present. The risk of lymph node metastasis in T1 CRC ranges from 1% to 36.4%, depending on histologic risk factors. Presence of any risk factor labels the patient "high risk," warranting oncologic surgery with mesocolic lymphadenectomy. However, even if 70%-80% of T1-CRC patients are classified as high-risk, more than 90% are without lymph node involvement after oncological surgery. Surgical overtreatment in T1 CRC is a challenge, requiring a balance between oncologic safety and minimizing morbidity/mortality. This narrative review explores the landscape of managing non-curative T1 colon cancer, focusing on the choice between advanced endoscopic resection techniques and surgical interventions. We discuss surveillance strategies and shared decision-making, emphasizing the importance of a multidisciplinary approach.

Colonoscopy quality improvement after initial training: A cross-sectional study of intensive short-term training.

Background and study aims High-quality is crucial for the effectiveness of colonoscopy and can be achieved by high-quality training and verified with assessment of key performance indicators (KPIs) for colonoscopy such as cecum intubation rate (CIR), adenoma detection rate (ADR) and adequate polyp resection. Typically, trainees achieve adequate CIR after 275 procedures, but little is known about learning curves for KPIs after initial training. Methods This cross-sectional study includes work-up colonoscopies after a positive screening test with fecal occult blood testing (FIT) or sigmoidoscopy, performed by either trainees after 300 training colonoscopies or by consultants. Outcome measures were KPIs. We assessed inter-endoscopist variation in trainees and learning curves for trainees as a group. We also compared KPIs for trainees and consultants as a group.  Results Data from 6,655 colonoscopies performed by 21 trainees and 921 colonoscopies performed by 17 consultants were included. Most trainees achieved target standards for main KPIs. With time, trainees shortened cecum intubation time and withdrawal time without decreasing their ADR, reduced the proportion of painful colonoscopies, and increased the adequate polyp resection rate (all P  < 0.01). Compared to consultants, trainees had higher CIR (97.7 % vs. 96.3 %, P  = 0.02), ADR after positive FIT (57.6 % vs. 50.3 %, P  < 0.01), and proximal ADR after sigmoidoscopy screening (41.1 % vs. 29.8 %; P  < 0.01), higher adequate polyp resection rate (94.9 % vs. 93.1 %, P  = 0.01) and fewer serious adverse events (0.65 % vs. 1.41 %, P  = 0.02). Conclusions Trainees performed high-quality colonoscopies and achieved international target standards. Several KPIs continuously improved after initial training. Trainees outperformed consultants on several KPIs.

Impact of time between faecal immunochemical tests in colorectal cancer screening on screening results: A natural experiment.

Repeated rounds of faecal immunochemical testing (FIT) for occult blood is a common method for screening for colorectal cancer (CRC). However, the time interval between FIT rounds is not thoroughly investigated. In a CRC screening trial in South-Eastern Norway, individuals were invited for biennial FIT between 2012 and 2019. The positivity threshold was >15 mcg haemoglobin/g faeces (mcg/g). Due to organizational challenges, the interval between screening rounds randomly varied between 1.5 and 3.5 years, forming a natural experiment. We investigated the detection rate of CRC and advanced neoplasia (AN: CRC or advanced adenoma) at the subsequent round (FIT2 ), according to the faecal haemoglobin concentration (f-Hb) at the initial screening round (FIT1 ), and time between the two screening rounds. 18 522 individuals with negative FIT1 who attended FIT2 were included in this study. 245 AN were detected at FIT2 , of which 34 were CRC. The CRC detection rate at FIT2 for participants with FIT1  = 0 mcg/g was 0.09% while it was 0.28% for participant with 0 > FIT1 ≤ 15 mcg/g; odds ratio (OR) 3.22, 95% CI 1.49-6.95. For each 3 months' increment between FITs, the OR for detecting CRC was 1.33 (95% CI 0.98-1.79), while the OR was 1.13 (1.02-1.26) for AN. Individuals with FIT1 -value of 0 mcg/g, had a lower AN detection rate compared with participants with 0 > FIT1 ≤ 15 mcg/g, irrespective of time between tests. Although CRC and AN detection rates increase with increasing time interval between FITs, individuals with undetectable f-Hb at first screen have substantially lower risk of CRC at the next screening round compared with individuals with detectable f-Hb.

Real-Time Artificial Intelligence-Based Optical Diagnosis of Neoplastic Polyps during Colonoscopy.

BACKGROUND: Artificial intelligence using computer-aided diagnosis (CADx) in real time with images acquired during colonoscopy may help colonoscopists distinguish between neoplastic polyps requiring removal and nonneoplastic polyps not requiring removal. In this study, we tested whether CADx analyzed images helped in this decision-making process. METHODS: We performed a multicenter clinical study comparing a novel CADx-system that uses real-time ultra-magnifying polyp visualization during colonoscopy with standard visual inspection of small (≤5 mm in diameter) polyps in the sigmoid colon and the rectum for optical diagnosis of neoplastic histology. After committing to a diagnosis (i.e., neoplastic, uncertain, or nonneoplastic), all imaged polyps were removed. The primary end point was sensitivity for neoplastic polyps by CADx and visual inspection, compared with histopathology. Secondary end points were specificity and colonoscopist confidence level in unaided optical diagnosis. RESULTS: We assessed 1289 individuals for eligibility at colonoscopy centers in Norway, the United Kingdom, and Japan. We detected 892 eligible polyps in 518 patients and included them in analyses: 359 were neoplastic and 533 were nonneoplastic. Sensitivity for the diagnosis of neoplastic polyps with standard visual inspection was 88.4% (95% confidence interval [CI], 84.3 to 91.5) compared with 90.4% (95% CI, 86.8 to 93.1) with CADx (P=0.33). Specificity was 83.1% (95% CI, 79.2 to 86.4) with standard visual inspection and 85.9% (95% CI, 82.3 to 88.8) with CADx. The proportion of polyp assessment with high confidence was 74.2% (95% CI, 70.9 to 77.3) with standard visual inspection versus 92.6% (95% CI, 90.6 to 94.3) with CADx. CONCLUSIONS: Real-time polyp assessment with CADx did not significantly increase the diagnostic sensitivity of neoplastic polyps during a colonoscopy compared with optical evaluation without CADx. (Funded by the Research Council of Norway [Norges Forskningsråd], the Norwegian Cancer Society [Kreftforeningen], and the Japan Society for the Promotion of Science; UMIN number, UMIN000035213.)

Acceptability of two colorectal cancer screening tests: pain as a key determinant in sigmoidoscopy.

Background Participants' experience with a screening test can influence adherence, and therefore the efficacy of screening programs. We compared screening with unsedated flexible sigmoidoscopy and fecal immunochemical testing (FIT) for participants' satisfaction with the decision and for willingness to repeat colorectal cancer screening. Methods In a prospective, randomized trial 3257 individuals (50 - 74 years) were invited to either flexible sigmoidoscopy or FIT (1:1), of whom 1650 took up the offer (52.6 %). In total, 1497 screening participants completed at least one questionnaire, either before screening, and/or at three time points in the following year, that measured willingness to repeat screening, willingness to recommend screening, and satisfaction with decision to attend. There were 769 and 728 responders in the flexible sigmoidoscopy and FIT group, respectively. Additionally, 581 flexible sigmoidoscopy participants also completed a pain questionnaire. Results 1 year later, 10 % of the flexible sigmoidoscopy participants were not willing to repeat screening, compared to 5 % of FIT participants. A higher percentage of women compared to men would not repeat flexible sigmoidoscopy screening (adjusted odds ratio [OR] 2.52, 95 % confidence interval [95 %CI] 1.48 to 4.28). Notably, 22 % of women reported pain during flexible sigmoidoscopy compared to 5 % of men. When we added pain to the statistical model, pain was significantly associated with unwillingness to repeat flexible sigmoidoscopy (OR 3.15, 95 %CI 1.68 to 5.87), while gender was no longer associated (OR 1.53, 95 %CI 0.82 to 2.88). Conclusion Acceptability for flexible sigmoidoscopy and for FIT was high among Norwegian screening participants, though FIT participants were more willing to repeat screening. Women were less willing to repeat screening with flexible sigmoidoscopy compared to men. This gender difference seemed partly due to pain, and therefore preventable.This study is registered at ClinicalTrials.gov: NCT01538550.