Recurrence rate of lateral margin-positive cases after en bloc endoscopic submucosal dissection of colorectal neoplasia

Predictors of residual neoplasia after noncurative (R1) endoscopic submucosal dissection of lesions in the gastrointestinal tract

BACKGROUND

Endoscopic submucosal dissection (ESD) is a minimally invasive resection technique that enables the en bloc resection of gastrointestinal lesions. Despite en bloc resection, pathological evaluation of lesions can reveal positive vertical or horizontal margins, which is referred to as R1 resection. Not all R1 lesions referred for surgical resection or endoscopic surveillance show evidence of residual tumor. We aimed to identify the predictors of residual neoplasia in patients with an R1 resection following ESD.

PATIENTS AND METHODS

All lesions resected via ESD between June 2016 and September 2021 at a tertiary referral center were retrospectively identified. Lesions with an R1 resection and adequate follow-up were eligible for inclusion. Patient, lesion, and procedural characteristics were analyzed to identify predictors of residual neoplasia.

RESULTS

Of 614 lesions, 163 (28%) had R1 resection. Of these, 56 lesions in 51 patients had complete follow-up and were included. Thirteen patients (25.5%) underwent surgical resection and the remainder underwent endoscopic surveillance. Seven (12.5%) patients had residual disease. All patients with residual disease had esophageal carcinoma. Positive deep and lateral margins, severe submucosal fibrosis, and moderate/poorly differentiated tumors were identified as significant predictors of residual neoplasia.

CONCLUSION

Most R1 lesions (87.5%) resected by ESD did not have residual disease on follow-up. Those without identified risk factors for residual disease, such as esophageal carcinoma, severe submucosal fibrosis, or both histological margin positivity, may benefit from a strategy of close endoscopic surveillance rather than referral for surgical resection.

Clinical outcomes of colorectal neoplasm with positive resection margin after endoscopic submucosal dissection

A positive resection margin after colorectal endoscopic submucosal dissection (ESD) is associated with an increased risk of recurrence. We aimed to identify the clinical significance of positive resection margins in colorectal neoplasms after ESD. We reviewed 632 patients who had en bloc colorectal ESD at two hospitals between 2015 and 2020. The recurrence rates and presence of residual tumor after surgery were evaluated. The rate of additional surgery after ESD and recurrence rate were significantly higher in patients with incomplete resection (n = 75) compared to patients with complete resection (n = 557). When focusing solely on non-invasive lesions, no significant differences in recurrence rates were observed between the groups with complete and incomplete resection (0.2% vs. 1.9%, p = 0.057). Among 84 patients with submucosal invasive carcinoma, 39 patients underwent additional surgery due to non-curative resection. Positive vertical margin and lymphovascular invasion were associated with residual tumor. Lymphovascular invasion was associated with lymph node metastasis. However, no residual tumor nor lymph node metastases were found in patients with only one unfavorable histological factor. In conclusion, a positive resection margin in non-invasive colorectal lesions, did not significantly impact the recurrence rate. Also, in T1 colorectal cancer with a positive vertical resection margin, salvage surgery can be considered in selected patients with additional risk factors.

Characteristics of positive horizontal margins in patients who underwent colorectal endoscopic submucosal dissection

Objectives

Endoscopic submucosal dissection (ESD) enables en bloc resection of colorectal neoplasms, but occasionally results in positive horizontal margins (HMs). However, the site of the resected specimen that tends to be positive for HM has not been investigated. We aimed to clarify the characteristics associated with HMs in lesions resected en bloc with ESD.

Methods

Patients with colorectal neoplasms who underwent en bloc resection with ESD were included in this study. The patients were divided into negative HMs (HM0) and positive or indeterminate HMs (HM1) groups. The characteristics associated with HM1 resection were investigated. In addition, the local recurrence rate during endoscopic follow-up for >6 months after ESD was observed.

Results

In total, 201 lesions were analyzed in 189 patients (HM0, 189 lesions; HM1, 12 lesions). The HM1 group had a significantly larger median lesion diameter (25 vs. 55 mm; p < 0.001) and more lesions with >50% circumference than did the HM0 group (p < 0.001). Furthermore, the prevalence of severe fibrosis was significantly higher in the HM1 group than in the HM0 group (p < 0.001). Positive horizontal sites of the resected specimens were more frequent at the oral and anal sites than at the lateral sites. No local recurrences were observed in either group.

Conclusions

The characteristics associated with HM1 depended on lesion size, particularly lesions with >50% circumference, and submucosal fibrosis.

Comparison of two pathological processing methods for large endoscopic submucosal dissection (ESD) specimens

AIMS

Accurate histopathological evaluation of the endoscopic submucosal dissection (ESD) specimens is essential for clinicians to guide further triage and management. This study aimed to report a novel processing technique for large ESD (≥4 cm) specimens.

METHODS

92 patients with colorectal neoplasms who had undergone ESD were included. 46 ESD specimens were treated with conventional handling process, while the rest 46 cases were given the optimised method. Macrobiocassettes and L-shaped embedding moulds were applied in the optimised method. We evaluated the efficacy of this improved procedure in terms of the number of paraffin blocks, storage space and time consumption of pathological assessment.

RESULTS

The average diameter of ESD specimens was 4.5±0.4 cm and 4.7±0.5 cm in the control and test group (p=0.023), respectively. In control group, 398 paraffin blocks of 46 cases were obtained. With the same cases number and larger lesion size, only 276 blocks were achieved in test group (p<0.001). As for the storage space, the total volume of paraffin blocks and slides (4554.0 cm3 and 1207.5 cm3) of optimised method was significantly reduced compared with the control group (6208.8 cm3 and 1741.3 cm3) (p=0.001, p<0.001). In addition, the optimised method was superior to the conventional one in shortening time consumption of pathological assessment (164.5 min and 269.0 min, p<0.001).

CONCLUSIONS

The optimised technique not only reduced the workload and storage space, but also facilitated accurate pathological assessment.

Low risk of local recurrence after a successful en bloc endoscopic submucosal dissection for noninvasive colorectal lesions with positive horizontal resection margins (R-ESD study)

BACKGROUND : During endoscopic submucosal dissection (ESD), the normal mucosa is cut under constant optical control. We studied whether a positive horizontal resection margin after a complete en bloc ESD predicts local recurrence.

METHODS

 In this European multicenter cohort study, patients with a complete en bloc colorectal ESD were selected from prospective registries. Cases were defined by a horizontal resection margin that was positive or indeterminate for dysplasia (HM1), whereas controls had a free resection margin (HM0). Low risk lesions with submucosal invasion (T1) and margins free of carcinoma were analyzed separately. The main outcome was local recurrence.

RESULTS

 From 928 consecutive ESDs (2011-2020), 354 patients (40 % female; mean age 67 years, median follow-up 23.6 months), with 308 noninvasive lesions and 46 T1 lesions, were included. The recurrence rate for noninvasive lesions was 1/212 (0.5 %; 95 %CI 0.02 %-2.6 %) for HM0 vs. 2/96 (2.1 %; 95 %CI 0.57 %-7.3 %) for HM1. The recurrence rate for T1 lesions was 1/38 (2.6 %; 95 %CI 0.14 %-13.5 %) for HM0 vs. 2/8 (25 %; 95 %CI 7.2 %-59.1 %) for HM1.

CONCLUSION

 A positive horizontal resection margin after an en bloc ESD for noninvasive lesions is associated with a marginal nonsignificant increase in the local recurrence rate, equal to an ESD with clear horizontal margins. This could not be confirmed for T1 lesions.

Endoscopic submucosal dissection for colorectal polyps: outcome determining factors

BACKGROUND

Endoscopic submucosal dissection (ESD) has gained increasing popularity in the management of complicated colorectal polyps. However, clinical outcomes for ESD have remained highly inconsistent worldwide. This study investigated and analysed factors that significantly affect ESD outcomes.

METHODS

We conducted a single-centred retrospective study on 220 colorectal polyps removed by ESD from 1st January 2016 to 31st December 2020. Data were collected and retrieved from clinical records. Variables studied included patient demographics, ESD technicalities and polyp characteristics. The primary outcome was completeness of resection based on en bloc and R0 resection rates. The secondary outcomes were recurrence, complications and hospital stay. Further analysis was performed for significant outcome determining factors.

RESULTS

The en bloc resection and R0 resection rates were 97.3% and 65% respectively. Intraprocedural and delayed perforation rates were 3.2% and 0.5% respectively. Intraprocedural and delayed bleeding rates were both 1.8%. Post-polypectomy syndrome rate was 2.7%. The median hospital stay was 4 days. Submucosal fibrosis was a significant determining factor for lower en bloc resection (p = 0.004), lower R0 resection (p = 0.002), intraprocedural perforation (p = 0.001), intraprocedural bleeding (p = 0.025) and post-polypectomy syndrome (p = 0.039). Hybrid snaring was associated with lower en bloc resection (p < 0.001), while longer ESD time was associated with lower R0 resection (p = 0.003) and post-polypectomy syndrome (p = 0.025). Other significant factors for post-polypectomy syndrome included young age (p = 0.021) and large polyp size (p = 0.018). Secondary analysis showed that submucosal fibrosis was significantly associated with non-granular lesions (p < 0.001) and prior biopsy (p = 0.003).

CONCLUSION

Submucosal fibrosis, hybrid snaring, ESD time, age and polyp size were significant outcome determining factors for ESD. By identifying these factors, strategies may be formulated to improve ESD outcomes.

Two histologic compartments in nonpolypoid conventional colon adenomas

Two intertwined compartments coexisting in nonpolypoid conventional (i.e. tubular or villous) adenomas are highlighted in this review: one built of dysplastic tissue on top and the other portraying crypts with irregular, corrupted shapes, albeit lined with normal epithelium, below. The latter compartment has remained unattended in the literature. Recently, however, the histologic characteristics of the nondysplastic compartment in nonpolypoid conventional adenomas were closely examined, and some of its biological attributes were unveiled. Studies with the proliferation marker ki67 showed that the crypts with irregular, corrupted shapes in the nondysplastic compartment displayed haphazardly distributed proliferating cell-domains. Given that the proliferating cells are generated by stem cells, the relocation of proliferating cell-domains in those crypts seems to be the result of a reorganization of the stem cells within the crypts. The abnormal distribution of proliferating cells, the finding of p53-upregulated cells, and of crypts in asymmetric fission suggest that the crypts in that compartment are histo-biologically altered, probably somatically mutated. This new information might contribute to unravel the riddle of crypto-histogenesis of nonpolypoid conventional adenomas of the colon. More research along these lines is necessary, before the biology of the crypts in the nondysplastic compartment can be fully translated into molecular terms.

Efficacy of early clip-with-line method for colorectal endoscopic submucosal dissection

BACKGROUND

Colorectal endoscopic submucosal dissection (ESD) remains demanding due to technical difficulties and high risk of perforation. Most of the reported traction methods are initiated after creating a mucosal flap, which is time consuming. To obtain a good visualization at the mucosal incision stage, we developed the early clip-with-line (ECL) method. This method was started immediately after injection of sodium hyaluronate solution into the submucosal layer. In this study, we evaluated the efficacy and the safety of the ECL method for colorectal ESD.

METHODS

We retrospectively analyzed all cases of colorectal ESDs (41 cases in total) performed from January 2017 to February 2019 in our institution. From January 2017 to August 2018, 27 of these cases were performed using conventional (non-ECL) ESDs, while from September 2018 onwards, the remaining 14 cases were performed using the ECL method. Retrospective comparison between the ECL group and the non-ECL group was conducted in terms of clinical characteristics, treatment outcomes, and adverse events.

RESULTS

There were no significant differences in clinical characteristics between two groups. Procedure time (median [range]) was significantly shorter in the ECL group than in the non-ECL group (66 [29-131] min vs 90 [30-410] min; P = 0.03). As for adverse events, no case of perforation occurred in the ECL group, whereas perforation was observed in 7.4% (2/27) cases in the non-ECL group (no significant difference).

CONCLUSION

Early clip-with-line method for colorectal endoscopic submucosal dissection reduced procedure time.

The effect of non-curative endoscopic resection on cT1N0M0 colorectal carcinoma patients who underwent additional surgery

BACKGROUND AND AIM

Radical surgery is recommended for T1 colorectal cancer with non-curative endoscopic resection. However, there is still insufficient evidence about whether the non-curative endoscopic resection prior to surgical resection affects the short-term and long-term outcomes of patients. The purpose of this study was to investigate the effect of non-curative endoscopic resection before surgical resection on short-term and long-term outcomes in patients with T1 colorectal cancer.

PATIENTS AND METHODS

Patients with clinical T1N0M0 (cT1N0M0) colorectal cancer who underwent direct surgery or additional radical surgery after non-curative endoscopic resection were collected. We evaluated postoperative complications and long-term prognosis between the two groups.

RESULTS

From 2011 to 2017, 779 patients were clinically diagnosed with T1N0M0 colorectal cancer at Zhongshan Hospital. We assessed patients who underwent additional surgery following the prior non-curative endoscopic resection (n = 145) and patients who underwent radical surgery directly (n = 336). There was no significant difference in 5-year OS (99.3% vs. 99.4%, P = 0.866) and 5-year DFS (97.2% vs. 97.3%, P = 0.909) between the two groups. The total complication rate was slightly higher in prior endoscopic resection group (15.2% vs. 9.5%, P = 0.111). The 5-year OS and 5-year DFS of patients who refused additional surgery (n = 95) were significantly lower than ER prior to surgery group (For OS, 92.6% vs. 99.3%, P = 0.017; for DFS, 91.2% vs. 97.2%, P = 0.021).

CONCLUSION

In patients who underwent additional surgery, non-curative endoscopic resection of cT1 colorectal carcinoma did not have adverse effect on short-term and long-term outcomes. Additional surgery should be recommended in patients who received non-curative ER.

Long-term outcomes of endoscopically resected laterally spreading tumors with a positive histological lateral margin

BACKGROUND

With advances in diagnostic endoscopy, the incidence of superficial colorectal tumors, including laterally spreading tumors (LSTs), has increased. However, little is known about the long-term results of LSTs with positive lateral margin after endoscopic treatment. This study aimed to evaluate the long-term clinical outcomes and risk factors for local recurrence of LSTs with positive lateral margin after initial endoscopic resection.

METHODS

We performed a retrospective analysis of the medical records of 324 patients who had 363 LSTs with positive lateral margin after endoscopic resection at a tertiary academic medical center. The medical records from 2011 to 2015 were analyzed. Local recurrence was confirmed through endoscopic finding and subsequent biopsy analysis. We assessed the local recurrence rate and performed multivariate analyses to identify the factors associated with local recurrence.

RESULTS

Follow-up colonoscopy was performed in 176 of 363 LSTs. The local recurrence rate was 6.3% (11/176), with a median (interquartile range [IQR]) follow-up period of 19.8 (12.4-46.5) months. In multivariate analysis, local recurrence was associated with piecemeal resection (odds ratio [OR] 6.62, 95% confidence interval [CI] 1.28-34.33; p = 0.024) and inversely associated with thermal ablation (OR 0.033, 95% CI 0.00-0.45; p = 0.011). At surveillance colonoscopy, histology of the recurrent tumor was adenoma in 10 (90.9%) of 11; these were treated endoscopically.

CONCLUSIONS

In this retrospective study, we found that endoscopically resected LSTs with positive lateral margin have a low recurrence rate. Piecemeal resection was associated with higher local recurrence, and thermal ablation was inversely associated with local recurrence. Endoscopic resection with positive lateral margin combined with thermal ablation leads to a low recurrence rate.

Effect of horizontal margin status and risk of local recurrence after endoscopic submucosal dissection for superficial esophageal cancer

Background and Aim

Endoscopic submucosal dissection (ESD) sometimes results in en bloc resection with a positive or inconclusive horizontal margin (HM1 or HMX, respectively) on histological evaluation. The specific risk for such situations is unclear. We therefore investigated the outcome of ESD with HM1 or HMX.

Methods

This single‐center retrospective study was performed at Osaka International Cancer Institute. A total of 886 esophageal squamous cell carcinoma lesions in 749 patients treated from April 2005 to June 2015 were evaluated according to the following inclusion criteria: en bloc resection with no residual lesion, HM1 or HMX status, no prior treatment, and no additional treatment. We classified HM1 and HMX into type A, in which cancer was exposed on the HM, and type B, in which the HM status was unclear because of mechanical or thermal damage. We further classified type B according to the distance between the cancer and the edge of the specimen: type B1, <1 mm and type B2, ≥1 mm.

Results

The resection margin was judged as HM1 or HMX in 5.0% (39/767; 95% confidence interval, 3.5–6.6%) of the en bloc resected specimens. Of 39 lesions, 30 fulfilled the inclusion criteria. Local recurrence developed in 8 of 30 lesions (26.7%). The local recurrence rates for types A, B1, and B2 were 40% (6/15 lesions), 28.5% (2/7 lesions), and 0.0% (0/8 lesions), respectively.

Conclusions

Although a statistical analysis was not conducted because of the limited events, the pathological HM status may be a useful predictor of local recurrence.