Published online Dec 27, 2022. doi: 10.4240/wjgs.v14.i12.1375
Peer-review started: July 16, 2022
First decision: October 30, 2022
Revised: November 13, 2022
Accepted: December 6, 2022
Article in press: December 6, 2022
Published online: December 27, 2022
Processing time: 164 Days and 1.4 Hours
Transanal total mesorectal excision (TaTME) allows patients with ultralow rectal cancer to be treated with sphincter-saving surgery. However, accurate delineation of the distal resection margin (DRM), which is essential to achieve R0 resection for low rectal cancer in TaTME, is technically demanding.
To assess the feasibility of optical biopsy using probe-based confocal laser end
A total of 43 consecutive patients who were diagnosed with low rectal cancer and scheduled for TaTME were prospectively enrolled from January 2019 to January 2021. pCLE was used to determine the distal edge of the tumor as well as the DRM during surgery. The final pathological report was used as the gold standard. The diagnostic accuracy of pCLE examination was calculated.
A total of 86 pCLE videos of 43 patients were included in the analyses. The sensitivity, specificity and accuracy of real-time pCLE examination were 90.00% [95% confidence interval (CI): 76.34%-97.21%], 86.96% (95%CI: 73.74%-95.06%) and 88.37% (95%CI: 79.65%-94.28%), respectively. The accuracy of blinded pCLE reinterpretation was 86.05% (95%CI: 76.89%-92.58%). Furthermore, our results show satisfactory interobserver agreement (κ = 0.767, standard error = 0.069) for the detection of cancer tissue by pCLE. There were no positive DRMs (≤ 1 mm) in this study. The median DRM was 7 mm [interquartile range (IQR) = 5-10 mm]. The median Wexner score was 5 (IQR = 3-6) at 6 mo after stoma closure.
Real-time in vivo pCLE examination is feasible and safe for selecting the DRM during TaTME for low rectal cancer (clinical trial registration number: NCT04016948).
Core Tip: Transanal total mesorectal excision (TaTME) allows patients even with ultra-low rectal cancer to be treated with sphincter-saving surgery. However, low rectal cancer resection with sphincter preservation may lead to a positive distal resection margin (DRM), with a high risk for local recurrence. Confocal laser endomicroscopy (CLE) enables the real-time, in vivo optical biopsy of living tissue. Real-time in vivo probe-based CLE examination can provide optical biopsy and is feasible and safe for selecting the DRM during TaTME for low rectal cancer.