Adenoma of the ampulla of vater
There is exophytic tumor at the ampullary orificeJuvenile polyp Large intestine
A and B, Outer aspect and cut surface of juvenile (retention) polyp. Note the ulcerated, highly hyperemic surface (A), and the cystically dilated glands in an edematous stroma (B).Juvenile polyp Large intestine
Whole-mount view of a juvenile (retention) polyp.Mucocutaneous pigmentation with a predominant perioral disposition.
Oral pigmentation in Peutz-Jeghers syndromeHamartomatous polyp of small bowel in 12-year-old girl. Tumor, which had caused intussusception, was not associated with other features of Peutz-Jeghers syndrome. A, Gross appearance of tumor, showing distinct lobulation, short stalk, and multiple small cysts. B, Panoramic view of microscopic section. Ramifying central stalk containing numerous muscle bundles supports florid epithelial proliferation. Many of glands show cystic dilatation.
Peutz-Jeghers polyp large intestine
Pedunculated adenomatous polyps.
Adenomatous polyp (tubular adenoma), LPThe polyp is composed of neoplastic glandular structures that appear darker then the adjacent normal glandular elements.
Villous adenoma colon
Lt., surface view; Rt., cross section at the right. Note that this type of adenoma is sessile, rather than pedunculated, and larger than a tubular adenoma (adenomatous polyp). A villous adenoma averages several centimeters in diameter, and may be up to 10 cm.Villous adenoma
Low-power microscopic appearance: long villi are arranged in parallel, perpendicularly to the mucosa.Villoglandular polyp.
There is an admixture of villous and glandular structures.Gross appearance of familial polyposis. The entire large bowel was involved. Note the fact that practically all of the polyps are small and sessile.
Polyposis with numerous small polyps covering the colonic mucosa. 18-year-old woman. The mucosal surface is carpeted by innumerable polypoid adenomas.
Adenomatous Familial Polyposis (AFP)
Morphologic & molecular changes in the adenoma-carcinoma sequence
Carcinoma large intestineCarcinoma of the cecum. The fungating carcinoma projects into the lumen but has not caused obstruction.
Adenoca descending colon The encircling mass of firm adenocarcinoma in this colon at the left is typical for adenocarcinomas arising in the descending Colon.
MP: the glands are large and filled with necrotic debris.
Adenocarcinoma colonHP, the neoplastic glands of adenocarcinoma have crowded nuclei with hyperchromatism and pleomorphism. No normal goblet cells are seen.
Invasive adenocarcinoma of colon, showing malignant glands infiltrating the muscle wall.
TNM classification of colo-rectal carcinoma
Pathologic staging of colorectal cancer. Staging is based on the depth of tumor invasion.H
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