Endoscopic features of submucosal deeply invasive colorectal cancer with NBI characteristics : S Saito et al. Endoscopic images of early colorectal cancer

First report from the International Evaluation of Endoscopic classification Japan NBI Expert Team: International multicenter web trial

OBJECTIVES

Narrow-band imaging (NBI) contributes to real-time optical diagnosis and classification of colorectal lesions. The Japan NBI Expert Team (JNET) was introduced in 2011. The aim of this study was to explore the diagnostic accuracy of JNET when applied by European and Japanese endoscopists not familiar with this classification.

METHODS

This study was conducted by 36 European Society of Gastrointestinal Endoscopy (ESGE) and 49 Japan Gastroenterological Endoscopy Society (JGES) non-JNET endoscopists using still images of 150 lesions. For each lesion, nonmagnified white-light, nonmagnified NBI, and magnified NBI images were presented. In the magnified NBI, the evaluation area was designated by region of interest (ROI). The endoscopists scored histological prediction for each lesion.

RESULTS

In ESGE members, the sensitivity, specificity, and accuracy were respectively 73.3%, 94.7%, and 93.0% for JNET Type 1; 53.0%, 64.9%, and 62.1% for Type 2A; 43.9%, 67.7%, and 55.1% for Type 2B; and 38.1%, 93.7%, and 85.1% for Type 3. When Type 2B and 3 were considered as one category of cancer, the sensitivity, specificity, and accuracy for differentiating high-grade dysplasia and cancer from the others were 59.9%, 72.5%, and 63.8%, respectively. These trends were the same for JGES endoscopists.

CONCLUSION

The diagnostic accuracy of the JNET classification was similar between ESGE and JGES and considered to be sufficient for JNET Type 1. On the other hand, the accuracy for Types 2 and 3 is not sufficient; however, JNET 2B lesions should be resected en bloc due to the risk of cancers and JNET 3 can be treated by surgery due to its high specificity.

Early Rectal Cancer and Local Excision: A Narrative Review

A rise in the incidence of early rectal cancer consequent to bowel-screening programs around the world and an increase in the incidence in young adults has led to a growing interest in organ-sparing treatment options. The rectum, being the most distal portion of the large intestine, is a fertile ground for local excision techniques performed with endoscopic or surgical techniques. Moreover, the advancement in endoscopic optical evaluation and the better definition of imaging techniques allow for a more precise local staging of early rectal cancer. Although the local treatment of early rectal cancer seems promising, in clinical practice, a significant number of patients who could benefit from local excision techniques undergo total mesorectal excision (TME) as the first approach. All relevant prospective clinical trials were identified through a computer-assisted search of the PubMed, EMBASE, and Medline databases until January 2024. This review is dedicated to endoscopic and surgical local excision in the treatment of early rectal cancer and highlights its possible role in current and future clinical practice, taking into account surgical completion techniques and chemoradiotherapy.

Dexmedetomidine is safe and effective for reducing intraprocedural pain in colorectal endoscopic submucosal dissection

Objectives

Endoscopic submucosal dissection (ESD) is effective for the resection of colorectal intramucosal lesions. This study was performed to examine the safety and effectiveness of using dexmedetomidine (DEX) in the anesthesia regimen of patients with colorectal lesions undergoing ESD.

Methods

We retrospectively examined 287 consecutive patients who underwent ESD for colorectal lesions in our institution from January 2015 to December 2021. Outcomes including the frequency of intraprocedural pain and adverse events were compared between the DEX and no DEX groups. Moreover, univariate and multivariate analyses were conducted for each clinical factor of intraprocedural pain. Intraprocedural pain was defined as patient-reported abdominal pain or body movement during the procedure.

Results

The incidence of intraprocedural pain was significantly lower in the DEX than in the no DEX group (7% vs. 17%, p = 0.02). The incidence of hypotension was also significantly higher in the DEX group (7% vs. 0%, p = 0.01), but no cerebrovascular or cardiac ischemic events occurred. In the univariate analyses, the diameter of the resected specimen, procedure time, no use of DEX, and total midazolam dose was associated with intraprocedural pain. The midazolam dose and DEX administration were significantly negatively correlated and the diameter of resected specimen and procedure time were significantly positively correlated. Multivariate logistic regression showed that no use of DEX was independently associated with intraprocedural pain (p = 0.02).

Conclusions

Adding DEX to the anesthesia regimen in patients undergoing colorectal ESD appears to be safe and effective for reducing intraprocedural pain.

Longly-attached cap can contribute to en bloc underwater endoscopic mucosal resection of 20-30 mm colorectal intramucosal lesions

Background and study aims  Underwater endoscopic mucosal resection (UEMR) is effective for colorectal intramucosal lesions. The aim of this study was to evaluate whether a longly-attached cap in UEMR improves the en bloc resection rate for 20-30 mm lesions. Patients and methods  We performed a retrospective study at a tertiary institute. Candidates for the study were systematically retrieved from an endoscopic and pathological database from October 2016 to December 2020. We assessed the procedural outcomes with UEMR for lesions ≥ 20 mm in size and the clinical factors contributing to en bloc resection. Results  A total of 52 colorectal lesions that underwent UEMR were included. The median procedure time was 271 (66-1264) seconds. The en bloc resection rate and R0 resection rate were 75 % and 73 %, respectively. Intraprocedural perforation occurred in one (1.9 %) case, but no bleeding occurred. Delayed bleeding occurred in one (1.9%) case, but no delayed perforation occurred. Regarding tumor size, macroscopic type, tumor location, and the presence or absence of a history of abdominal operation, there was no significant difference between the en bloc resection and piecemeal resection groups. The visibility of the whole lesion, a longly-attached cap, and sessile serrated lesions were more frequently observed in the en bloc resection group than in the piecemeal resection group ( P  < 0.001, P  = 0.01, and P  = 0.04, respectively). Multivariate analysis showed that a longly-attached cap was the only independent factor associated with en bloc resection ( P  = 0.02). Conclusions  A longly-attached cap might contribute to en bloc resection.

Is barium enema examination negligible for the management of colorectal cancer? Comparison with conventional colonoscopy and magnifying colonoscopy

PURPOSE

The aim of this investigation was to evaluate the clinical value of barium enema (BE) examination for the management of colorectal epithelial neoplasms.

METHODS

We reviewed the colonoscopy records at our institution from 2014 to 2019 and identified cases of endoscopically or surgically resected colorectal epithelial neoplasms evaluated by BE, conventional colonoscopy, magnifying narrow-band imaging colonoscopy (M-NBI), and magnifying chromoendoscopy (MCE). The yield of each modality for the diagnosis of massively submucosal invasive (mSM) colorectal cancer was evaluated by a receiver-operating characteristic analysis including the area under the curve (AUC).

RESULTS

We analyzed the records of 105 patients (17 adenomas, 53 high-grade dysplasias (HGDs), and 35 cancers). Smooth surface, irregularity in depression, and eccentric deformity on the profile view with BE were observed more frequently in mSM cancers than adenomas/HGDs/slightly submucosal invasive cancers (p < 0.01). The AUC of BE was 0.8355, the value of which was not different from the other three modalities (conventional colonoscopy 0.7678; M-NBI 0.7835; MCE 0.8376). Although the specificity, PPV, and accuracy of BE were lower than those of M-NBI and MCE, the sensitivity and NPV of BE were the highest among the four types of examinations.

CONCLUSION

BE is still available and may serve as a supplementary modality for the diagnosis of mSM cancers.

Estimation of invasion depth of early colorectal cancer using EUS and NBI-ME: a meta-analysis

BACKGROUND

Endoscopic ultrasonography (EUS) and narrow band imaging-magnifying endoscopy (NBI-ME) are often used as diagnostic tools to estimate the depth of invasion in early colorectal cancer (CRC). The aim of this study was to compare NBI-ME with EUS in distinguishing between slight submucosal invasion (invasion depth < 1000 μm) and massive submucosal invasion in patients with early CRC, since slight submucosal invasion is currently considered as an indication for endoscopic resection.

METHODS

For this meta-analysis, relevant studies were identified from PubMed, Embase, Web of Science, Scopus and the Cochrane Library databases between January 1997 and September 2016. Data on the yield of tumors were extracted, pooled, and analyzed by stata12.0 software. The sensitivity, specificity, positive likelihood ratio and negative likelihood ratio in differentiating slight submucosal invasion from massive submucosal invasion were calculated for both diagnostic modalities.

RESULTS

Sixteen studies involving 2197 lesions were included: nine were studies on EUS and 7 were studies on NBI-ME. The pooled sensitivity of EUS was 0.902 (95% CI 0.863-0.930), the specificity was 0.877 (95% CI 0.810-0.922), the positive likelihood ratio was 7.314 (95% CI 4.551-11.755) and the negative likelihood ratio was 0.112 (95% CI 0.076-0.164). The pooled sensitivity and specificity of NBI-ME were 0.981 (95% CI 0.949-0.993) and 0.651 (95% CI 0.600-0.699), respectively, the positive likelihood ratio was 2.815 (95% CI 2.432-3.258) and the negative likelihood ratio was 0.029 (95% CI 0.010-0.080).

CONCLUSIONS

The sensitivity tended to be higher in ME-NBI than EUS for early CRC with slight submucosal invasion, whereas the specificity was significantly lower in NBI-ME than in EUS.

Preoperative endoscopic predictors of severe submucosal fibrosis in colorectal tumors undergoing endoscopic submucosal dissection

Background and study aims  Endoscopic submucosal dissection (ESD) enables en bloc removal of colorectal neoplasms regardless of size. Submucosal fibrosis is a significant factor for technical difficulty and poor outcomes. We assessed the predictive factors for severe submucosal fibrosis and the ESD outcomes. Patients and methods  Patients undergoing ESD from January 2006 to September 2017 were retrospectively reviewed. The degree of submucosal fibrosis was classified into three types: no fibrosis (F0), mild fibrosis (F1), and severe fibrosis (F2). F0 and F1 cases were grouped as non-severe fibrosis for comparison with the severe fibrosis group. Predictors of severe submucosal fibrosis and ESD outcomes were evaluated. Results  ESD was performed in 524 lesions (60 % male; mean age, 67.8 years). Eighty lesions with severe fibrosis (15.3 %) were observed. The overall en bloc resection rate and curative resection rate were 94.3 % and 77.7 %, respectively. Rates of en bloc resection (91.2 % vs. 94.8 %, P  = 0.2) and perforation (7.5 % vs. 5.6 %, P  = 0.45) were no different between severe fibrosis and non-severe fibrosis groups. However, incidences of non-curative resection and low resection speed were significantly higher in the severe fibrosis group. Among protruding lesions, tumor height and volume were significantly greater in the severe counterparts. A diameter ≥ 40 mm, endoscopic finding of the tumor beyond fold, and fold convergence were independent risk factors for severe fibrosis. Conclusions  Severe submucosal fibrosis is a significant risk factor for non-curative resection and a long procedural time. Tumor size and morphology might help to predict the severity of fibrosis.

Prediction of colorectal tumor grade and invasion depth through narrow-band imaging scoring

AIM

To determine the usefulness of assigning narrow-band imaging (NBI) scores for predicting tumor grade and invasion depth in colorectal tumors.

METHODS

A total of 161 colorectal lesions were analyzed from 138 patients who underwent endoscopic or surgical resection after conventional colonoscopy and magnifying endoscopy with NBI. The relationships between the surface and vascular patterns of the lesions, as visualized with NBI, and the tumor grade and depth of submucosa (SM) invasion were determined histopathologically. Scores were assigned to distinct features of the surface microstructures of tubular and papillary-type lesions. Using a multivariate analysis, a model was developed for predicting the tumor grade and depth of invasion based on NBI-finding scores.

RESULTS

NBI findings that correlated with a high tumor grade were associated with the “regular/irregular” (P < 0.0001) surface patterns and the “avascular area” pattern (P = 0.0600). The vascular patterns of “disrupted vessels” (P = 0.0714) and “thick vessels” (P = 0.0133) but none of the surface patterns were associated with a depth of invasion of ≥ 1000 μm. In our model, a total NBI-finding score ≥ 1 was indicative of a high tumor grade (sensitivity: 0.97; specificity: 0.24), and a total NBI-finding score ≥ 9 (sensitivity: 0.56; specificity: 1.0) was predictive of a SM invasion depth ≥ 1000 μm. Scores less than these cutoff values signified adenomas and a SM invasion depth < 1000 μm, respectively. Associations were also noted between selected NBI findings and tumor tissue architecture and histopathology.

CONCLUSION

Our multivariate statistical model for predicting tumor grades and invasion depths from NBI-finding scores may help standardize the diagnosis of colorectal lesions and inform therapeutic strategies.