Abstract
Background Large (≥ 20 mm) nonpedunculated colorectal lesions have high rates of synchronous
neoplasia and advanced neoplasia. Synchronous neoplasia prevalence in patients with
large pedunculated lesions is uncertain. We describe synchronous neoplasia in patients
with large pedunculated colorectal polyps, using a cohort of patients with large nonpedunculated
lesions as controls.
Methods This study was a retrospective assessment of a prospectively recorded database listing
synchronous findings in patients with ≥ 20 mm colorectal lesions referred to a tertiary
center for endoscopic resection.
Results At least one synchronous precancerous lesion was identified in 66/78 patients with
large pedunculated index lesions (84.6 %, 95 %CI 74.9–91.1) and 726/814 patients with
large nonpedunculated index lesions (89.2 %, 95 %CI 87.1–91.3). Patients with a large
pedunculated index lesion had mean of 4.8 synchronous conventional adenomas, 56.4 %
had ≥ 1 synchronous high risk lesion (advanced adenoma or advanced serrated lesion),
48.7 % had ≥ 1 synchronous advanced conventional adenoma, and 19.2 % had a synchronous
neoplastic lesion ≥ 20 mm. Compared with patients with nonpedunculated index lesions,
patients with large pedunculated index lesions had comparable rates of synchronous
polyps, adenomas, and sessile serrated lesions, and higher rates of synchronous adenomas
with villous elements (15.6 % [95 %CI 13.3–18.3] vs. 26.9 % [95 %CI 18.3–37.7]; P = 0.01) and synchronous pedunculated polyps (9.5 % [95 %CI 7.6–11.7] vs. 33.3 % [95 %CI
23.8–44.4]; P < 0.001).
Conclusion In patients with large (≥ 20 mm) pedunculated colorectal lesions, rates of synchronous
neoplasia and advanced synchronous neoplasia were high and comparable to or higher
than rates of synchronous neoplasia in patients with large nonpedunculated colorectal
lesions.
