Background and study aims: Endoscopic mucosal resection and submucosal dissection can provide curative endoscopic
therapy for Paris type I/II adenomas and node-negative early cancer. No studies have
addressed the technical feasibility of retroflexion endoscopic dissection methods
for luminal “salvage” therapy in patients considered unresectable using conventional
forward-viewing resection.Patients and methods: Colonoscopy using an Olympus GIF-XQ240 gastroscope was carried out in 76 patients
with Paris type I/II adenomas, early colorectal cancer (CRC), or laterally spreading
tumors (LSTs) when the index endoscopist considered the lesion to be unresectable
due to retrograde fold involvement. Endoscopic mucosal resection (EMR) and submucosal
dissection were carried out using a complete retroflexion technique. Endoscopic and
miniprobe 20-MHz or 12.5-MHz ultrasound follow-up data were collected prospectively
up to 24 months after the index resection.Results: Cecal intubation or cannulation to the neoterminal ileum was achieved in 76 (100
%) cases. Forty lesions (53 %) were classified in accordance with the Paris criteria
as Is; 16 (21 %) as type II; 10 (13.5 %) as LST-G; and 10 (13.5 %) as LST-NG. Eight
lesions (10 %) were excluded from EMR on the basis of endoscopic ultrasound criteria,
with 68 of the 76 lesions (89 %) meeting the criteria for endoluminal resection. The
median intubation time was 16 min (range 3 - 32 min). The median resection times were
98 min (range 30 - 242 min), 36 min (range 10 - 60 min), 172 min (range 20 - 240 min),
and 60 min (range 10 - 116 min) for Paris Is, II, LST-G, and LST-NG lesions, respectively.
LST-G morphology was associated with a high median submucosal injection volume in
comparison with all other Paris types (P < 0.05) and with a prolonged resection time (P < 0.01). Sixty-one patients (94 %) completed the surveillance protocol. Higaki recurrence
criteria were met in seven patients (11 %), with six undergoing successful adjunctive
endoluminal resection. After 24 months of follow-up, the “cure” rate with endoscopic
resection was 60 out of 61 (98 %).Conclusions: This is the first prospective study to address the safety and medium-term efficacy
of retroflexion endoscopic resection in the colon. When appropriate exclusion criteria
are applied, selected patients can receive curative resection using the retroflexion
technique. “Salvage” endoluminal therapy may therefore be possible in such cases when
surgical resection would otherwise have been required.
References
p.hurlstone@shef.ac.uk
