Successful planned piecemeal endoscopic resection using gel immersion and an over-the-scope clip for a lesion extensively extended into the colonic diverticulum

Abstract

Video 1Successfully planned piecemeal endoscopic resection using gel immersion and an over-the-scope clip for a lesion extensively extended into the colonic diverticulum.

Figure 1

Endoscopic views. A, 20-mm flat elevated lesion around and into the diverticulum near the ileocecal valve of the ascending colon. The size of the diverticulum was approximately 10 mm. B, The lesion extended considerably into the diverticulum, almost covering the orifice.

Figure 2

Preoperative endoscopic appearance of the lesion. A, Conventional endoscopic imaging. B, Magnification endoscopy with narrow-band imaging (NBI) for the green square in panel A. The image shows that the lesion had a variable caliber with irregular distribution and an irregular obscure surface pattern. These findings correspond with a type 2B lesion, according to the Japan NBI Expert Team classification. C, Magnifying chromoendoscopy with crystal violet staining for the purple square in panel A. The image shows that the lesion had pits of irregular arrangements. These findings correspond to a V_I-low grade type pit pattern classification.

Figure 3

Difference in endoscopic view between underwater and gel immersion. A, Underwater view. Injected water mixed with luminal residues; securing a clear view of the lesion was challenging. B, Gel immersion view. We injected gel (VISCOCLEAR; Otsuka Pharmaceutical Factory, Tokushima, Japan) through the accessory channel (BioShield irrigator; US Endoscopy, Mentor, Ohio, USA).

Figure 4

Gel immersion EMR (GIEMR). A, The accurate snaring of the lesion in clear gel immersion view. The lesion is resected with a snare (SnareMaster: 25-mm diameter; Olympus, Tokyo, Japan) without local injection. B, Resection defect after GIEMR. The lesion outside the diverticulum is completely resected, and only the lesion inside the diverticulum remains (yellow square).

Figure 5

Endoscopic resection using an over-the-scope clip (OTSC) for a lesion remaining inside the diverticulum. A, The OTSC (Ovesco Endoscopy GmbH, Tübingen, Germany) is deployed outside the diverticulum. The remaining lesion is resected above the OTSC with a snare. B, Resection defect without perforation. The small protrusion tissue (yellow arrow) may be a perforating branch vessel within the diverticulum.

Figure 6

Macroscopic images of the piecemeal resected specimens. A, Gross appearance of the tumor outside the diverticulum (22 × 21 mm). B, Gross appearance of the tumor inside the diverticulum (17 × 12 mm). C and D, Histopathologic mapping of the specimens. The laterally spreading adenoma lesion is shown in yellow, whereas the focal adenocarcinoma component is marked in red.

Figure 7

Histopathologic examination of specimens with a loupe (H&E, orig. mag. ×9.5 [A] and mag. ×17 [B]). A, Microscopic images of the tumor outside the diverticulum. B, Microscopic images of the tumor inside the diverticulum. In both specimens, the tumor is diagnosed as an intramucosal adenocarcinoma in high-grade adenoma with no lymphovascular invasion. The horizontal margin is diagnosed as inconclusive and the vertical margin is diagnosed as negative.

Figure 8

Follow-up endoscopic images. A, A conventional endoscopic image. The resection defect completely scarred within 2 months. B, Weak magnification endoscopic image with narrow-band imaging. No residual tumors were identified.