An interventional study of WLE followed by NBI or NBI followed by WLE (crossover design) in Colorectal Cancer and Recurrence, Local Neoplasm, sponsored by Portuguese Oncology Institute, Coimbra. Completed at 1 site in Portugal. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2022-10-05.
Sponsored by Portuguese Oncology Institute, Coimbra · Not applicable, Interventional, and Diagnostic
Nowadays endoscopic mucosal resection (EMR) is the gold standard for the removal of large laterally spreading and sessile colorectal lesions ≥ 20 mm. However, recurrence rate after successful EMR (defined by the absence of neoplastic tissue at the completion of the procedure after careful inspection of the post-EMR mucosal defect and margin) is about 15-20%. Consequently, current guidelines recommend a surveillance colonoscopy between 4 and 6 months after resection for detection of residual or recurrent polyp.
There are few studies that have examined the accuracy of advanced endoscopic imaging for the prediction of histological recurrence but none of these imaging modalities have been validated for surveillance after EMR. Therefore, current guidelines strongly recommend systematic biopsy of EMR scar.
The main aim of this study is to assess the incremental benefit of narrow band imaging (NBI) and white light endoscopy (WLE) randomizing the initial technique for the endoscopic detection of post-EMR recurrence and to asses if this advanced imaging method achieve sufficient diagnostic accuracy to exclude recurrence without the need for biopsy.
a. Study type: multicenter randomized crossover trial: i. prospective inclusion of consecutive patients undergoing first follow-up surveillance colonoscopy after successful EMR of colorectal lesion; ii. crossover randomization by computer generated tables; iii. allocation concealment by sealed, opaque envelopes; iv. pathologist-blinded - pathologists are blinded to the study protocol and samples are received as 'EMR scar for assessment' .
b. Selection patient method: inclusion by invitation of patients undergoing the first follow-up surveillance colonoscopy after successful EMR of colorectal lesion.
c. Sample size: 210 (two groups of 105 patients). To improve accuracy from 85% (value obtained by a study that did not show significant differences in the accuracy of NBI followed by WLE vs. WLE followed by NBI) to 95% and assuming a normal distribution and a power of 80% (α=0.05), the calculated sample size of each of the 2 groups was 96; allowing for a 10% dropout rate, the sample size is 105 per group (210 patients overall).
d. Procedures and data collection methods: i. Each procedure is performed by the same endoscopist. ii. All patients receive split dose bowel preparation. iii. All colonoscopies are performed using high definition colonoscopes with NBI ( EVIS EXERA III CV 185 and CV 190; Olympus Inc., Tokyo, Japan). iv. Colon inspection is done with WLE during withdrawal. v. At the proximity of the scar WLE and NBI were used randomly one after the other (WLE>NBI or NBI>WLE). If NBI is the first technique used, it is switched prior to scar detection, avoiding, as far as possible, a glance with WLE. The edges of the scar are interrogated followed by the centre of the scar and finding are recorded. vi. After both evaluations, if there is no suspicion of recurrence, the site is sampled by at least 2 biopsies of the scar edge. If there is any suspicion of recurrence, tissue sample is obtained and then treated by endoscopic resection using standard methods. At least 2 biopsies specimens from normal appearing scar are also obtained.
e. Analysed variables: i. patient characteristics; ii. data from baseline colonoscopy; iii. data from first surveillance colonoscopy (see outcome measures).
f. Statistical analysis: i. Performed using statistical software IBM SPSS Statistics, Version 25.0. Armonk, NY: IBM Corp. ii. Continuous variables are reported as mean and standard deviation or median and interquartile range, if they have normal or not normal distribution, respectively; categorical variables as absolute and relative frequency. iii. Continuous variables are compared between two groups using Student's T test if they have a normal distribution and homogeneity of variance or Mann-Whitney U if these conditions are not met. Categorical variables are compared using Pearson's X2 test or Fisher test. iv. Sensitivity, specificity, negative and positive predictive values and accuracy are calculated using 2x2 contingency tables. v. All hypotheses are two-tailed and a P-value\<0.05 is considered statistically significant.
36 studies on the registry are indexed under Neoplasm Recurrence, Local; 13 are open to participants now.
This study's enrollment of 210 is below the median of 237 across 26 interventional studies indexed under Neoplasm Recurrence, Local.
Browse Neoplasm Recurrence, Local studies →Portuguese Oncology Institute, Coimbra is the lead sponsor of 7 studies on the registry; 2 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
EMR scar is interrogated using WLE followed by NBI
Diagnostic Test: WLE followed by NBI or NBI followed by WLE (crossover design)
EMR scar is interrogated using NBI followed by WLE
Diagnostic Test: WLE followed by NBI or NBI followed by WLE (crossover design)
EMR scar is inspected using WLE followed by NBI or vice versa
Also known as: WLE followed by NBI or NBI followed by WLE
Diagnostic performance of WLE and NBI for each group
Sensitivity, specificity, negative predictive value, positive predictive value and accuracy of NBI and WLE for each group calculated using 2x2 contingency tables
Time frame: 1 day (at the time of data analysis)
Recurrent adenoma - WLE
WLE recurrent adenoma identification for each group
Time frame: 1 day (during colonoscopy)
Recurrent adenoma - NBI
NBI recurrent adenoma identification for each group
Time frame: 1 day (during colonoscopy)
Recurrent adenoma - histology
Adenoma recurrence confirmed by histology
Time frame: 1 day (within 30 days from colonoscopy)
Lesion characterization at the baseline colonoscopy
Lesion size and location, Paris classification, NICE classification, number of pieces, use of adjunctive ablative techniques and those identification and histology. Data collected by endoscopic reports consultation
Time frame: 1 day (at the time of patient inclusion)
Scar characterization at the first surveillance colonoscopy
Scar size, presence or absence of recurrence, in case of recurrence: number of sites, location (edge of the scar, within the scar or both), morphology of recurrence, NICE classification (for NBI evaluation)
Time frame: 1 day (immediately after first surveillance colonoscopy)
This study is completed, as verified in Oct 2022. You cannot join it, but the record below documents what was studied.
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Portuguese Oncology Institute, Coimbra