Males tend to be more often affected than females.
Clinical features:
(1) A colonic disorder that may be solitary, localized or diffuse.
(2) There may be a history of bacillary dysentery or other forms of colitis.
(3) The colonic mucosa may appear nodular due to cysts in the submucosa which may measure up to 2 cm in diameter.
(4) The submucosal cysts may be partially or completely lined by a cuboidal or columnar colonic epithelium. Older lesions may lose the epithelial lining and show a fibrous wall with chronic inflammation.
Features suggesting colloid carcinoma:
(1) dysplastic or overtly malignant epithelial cells
(2) desmoplasia
(3) irregular mucin pools
The differential diagnosis includes:
(1) diverticulosis (the cystic areas are beyond the muscularis propria)
(2) endometriosis (in a woman; shows endometrial glands and stroma)
