Fig. 2

Colonic segment with attached pericolonic fat measuring 12 cm in length and 6 cm in diameter. The serosa is tan–pink and smooth. Upon opening, the mucosa is tan–pink, soft with normal bowel folds. Attached to the folds, multiple large nodules are identified ranging from 0.5 to 3.0 cm. The entire nodular area measures 8.4 × 3.5 × 2 cm. Upon sectioning, the nodules deflate and are consistent with air bubbles (a, b). Microscopically, the section of the colon showed multiple air-filled cystic structures located in the submucosa. The cysts were lined by macrophages and multinucleated giant cells with bland nuclei. No atypia, pleomorphism, or mitoses were identified. The overlying colonic mucosa exhibited mild reactive changes but did not show significant inflammation or adenomatous change (c)