Endoscopic submucosal dissection of recurrent, circumferential, distal rectal tumor with severe submucosal fibrosis using multiple clip-line tractions

Video Video 1 Endoscopic submucosal dissection for a recurrent, circumferential, distal rectal tumor.


PROCEDURE
ESD was planned using the multiple tunnel technique. 2owever, since the lesion was just above the anal verge, and because of the SSF from the previous ESD and steroid injection (Fig. 3), neither mucosa nor adequate submucosa could be preserved.This led to the lesion falling proximally into the lumen, impairing submucosal visibility (Fig. 4).Thus, 3 clip-line tractions 3 were placed in a triangular manner over the lesion at the beginning of each tunnel (Fig. 5).En bloc resection was achieved, and tractions were removed from the specimen.Again, 40 mg of triamcinolone was injected equally into all 4 quadrants of the ulcer floor to prevent stricture formation.The procedure time was 300 minutes.No antibiotics were administered during or after the procedure.

OUTCOME
The specimen measured 110 Â 75 mm (Fig. 6).There were no adverse events during and immediately after the procedure.The patient was discharged on day 5. Pathology reported a tubular adenoma with high-grade dysplasia with negative margins (Fig. 7).A follow-up endoscopy after 45 days revealed no stricture with complete mucosal healing and no residual lesion (Fig. 8).

DISCUSSION AND CONCLUSION
The GI lumen has a limited size, making resection of a circumferential lesion difficult.To prevent the lesion falling into the lumen by gravity and obscuring the view, techniques such as the multiple tunneling technique, 2 pocket creation method, 4 and palisade technique 5 have been described.
The additional challenge in this case is SSF from the previous ESD and subsequent triamcinolone injection.The double tunnel method 6 had been previously reported to manage SSF.
We decided to use the multiple tunnel technique.Intraprocedure, it was not possible to preserve mucosa because of the distal extent of the lesion located just above the anal verge leading to a very narrow space.We modified our strategy to use the palisade technique.However, it was not possible to preserve adequate submucosal tissue because of the SSF and the angle of dissection at such a distal location being steeply downward.Therefore, the lesion collapsed into the lumen.Various reports have been published about traction techniques for ESD. 7We strategized to use multiple clip-line tractions 4 to draw the lesion outward and created space as required by adjusting the di-rection of external pull.It facilitated visibility and managed the SSF.
Recent reports have described novel methods of using a cell sheet 8 or a polyglycolic acid sheet with fibrin 9 glue for post-ESD stricture prevention in the esophagus.There is no standardization regarding management of strictures after colorectal ESD.We used a triamcinolone injection as per protocol. 10n conclusion, recurrent, circumferential lesions are rare and very challenging.Such large rectal tumors can be removed en bloc safely by applying adequate traction at multiple points, even when located distally.It is impor-tant to have the knowledge and experience to apply different ESD techniques to manage such complex cases.

DISCLOSURE
The authors did not disclose any financial relationships.

Figure 1 .
Figure 1.Past endoscopic submucosal dissection.A, Tumor in retroflexion view with white light.B, Tumor from retroflexion view with narrow-band imaging (NBI).C, Tumor from forward view with white light.D, Tumor from forward view with NBI.E, Ulcer from forward view.F, Ulcer in retroflexion.G, En bloc specimen.

Figure 2 .
Figure 2. Circumferential, laterally spreading Japan Narrow-Band Imaging Expert Team type 2A tumor.A, Retroflexion view with white light (previous endoscopic submucosal dissection [ESD] scar indicated by arrow).B, Retroflexion view from chromoendoscopy with indigo carmine (previous ESD scar indicated by arrow).C, Narrow-band imaging (NBI) showing proximal demarcation line around 5 cm from the anal verge.D, NBI showing the distal demarcation line just above the anal verge.

Figure 4 .
Figure 4. Lesion falling into lumen because of cutting of anchoring mucosa and submucosa.

Figure 5 .
Figure 5. A, Three clip-line tractions applied in a triangular manner.B, Schematic showing multiple tunnels and clip-line tractions.