1. Digestive pathology I

2. Chronic peptic ulcer From: Stevens A. J Lowe J. Pathology. Mosby 1995 Fig. 21.1. Deep loss of substance, often single, round or oval, with a diameter of 1-2 cm or more (giant ulcer), lined by prominent edges (normal mucosa) with mucous folds that radiate around ulcer; the ulcer base is clean, smooth and firm (fine granular).

3. From cases of the Pathology Department - U.M.F. “Gr. T. Popa” Iasi Fig. 21.2. CPU: (1) Deep loss of substance involving mucosa, muscular mucosa, submucosa, and muscle layer; (2) Ulcer edges contain normal gastric mucosa or with inflammatory lesions; (3) Ulcer base - 4 overlapping layers, from surface to depth.

4. Chronic peptic ulcer From cases of the Pathology Department - U.M.F. “Gr. T. Popa” Iasi Fig. 21. 3

5. Fig. 21.4. Ulcer base presents four overlapping layers, from surface to depth: (a) fibrino-leucocytic exudate; (b) fibrinoid necrosis; (c) granulation tissue; (d) fibrous tissue. Deep layer of mature fibrous tissue contains thick-walled vessels (non- specific obliterative endarteritis).

6. Advanced gastric carcinoma From: Stevens A. J Lowe J. Pathology. Mosby 1995 Fig. 21. 5. - 3 types of growth: (1) vegetative or polypoid mass that protrudes into the lumen; (2) malignant ulcer with raised edges; or (3) diffusely infiltrative lesion that causes thickening and contraction of the stomach wall with narrowing of the lumen.

7. Fig.6 Fig. 21.6. Difusse infiltrative carcinoma (linitis plastica): entire stomach is involved with preserving the shape; the gastric wall is thick and rigid; the gastric mucosa is smooth, without folds, and the gastric lumen, is reduced considerably.

8. Gastric carcinoma of intestinal type From cases of the Pathology Department - U.M.F. “Gr. T. Popa” Iasi Fig. 21.7

9. Fig. 21.7-8.Malignant tumor cells are arranged in irregular tubular structures and infiltrate gastric wall. Stroma between tumoral glands is reduced (appearance of "back in back“ glands).

10. Gastric carcinoma of diffuse type with “signet ring cells” From cases of the Pathology Department - U.M.F. “Gr. T. Popa” Iasi Fig. 21.9

11. Fig. 21.10 Fig.9-10.Infiltrated tumor composed from tumor cells produce intracellular mucus. The nucleus of tumor cells is displaced to the periphery by mucus “signet ring cells“.

12. Gastric carcinoma of diffuse type colloid carcinoma From cases of the Pathology Department - U.M.F. “Gr. T. Popa” Iasi Fig. 21.11

13. Fig.11-12.Tumor cells produce mucus which is accumulated extracellulary. The sheets of mucus contains tumor cells, disposed in various patterns (tubes, cords, nests), dissect the layers of the gastric wall. Fig. 21.12

14. Meckel diverticulum From: Stevens A. J Lowe J. Pathology. Mosby 1995 Fig. 21.13 Fig.13. It results by involution of the omphalomesenteric (vitelline) duct. It appears as a sac or glove finger structure, with a length of 5-6 cm. It contains all layers of intestinal wall and thus is a true diverticulum.

15. Colonic diverticulosis From: Stevens A. J Lowe J. Pathology. Mosby 1995 Fig.14. Pseudodiverticuli are herniations of the mucosa and submucosa of large intestine, into the pericolonic fat by parietal defects of the muscle layer. Fig. 21.14

16. Crohn disease From: Stevens A. J Lowe J. Pathology. Mosby 1995 Fig. 15. In the affected segment, the mucosa has a cablestone appearance (paving stones), which is determined by mucosal or submucosal edema (inflammatory edema), separated by deep, linear, interconnected fissures or ulcers. Fig. 21.15

17. Ulcerative colitis From: Stevens A. J Lowe J. Pathology. Mosby 1995 Fig.16. In active phase, mucosa is edematous, hyperaemic, with microhemorrages and small suppurative foci (microabscesses); ulcers result by elimination of the necrotic mucosal areas. The uninvolved mucosa has a pseudopolypoid appearance (inflammatory pseudo-polyps). Fig. 21.16

18. Tubular Adenoma From: Stevens A. J Lowe J. Pathology. Mosby 1995 Fig. 21.17. Adenomatous tubular polyps are pedunculated nodules, with short and thin pedicle, a short base of implantation and nodular or globular extremity. Fig. 21.17

19. Colonic adenoma From: Stevens A. J Lowe J. Pathology. Mosby 1995 Fig. 21.18. Villous adenoma: sesile tumors with broad base of implantation, with or papillary or villous appearance. Tubulo-villous adenoma presents intermediate features between tubular adenoma and villous adenoma. Fig. 21.18

20. Colonic carcinoma From: Stevens A. J Lowe J. Pathology. Mosby 1995 Fig. 21.19. Vegetative carcinoma: tumor presents a large, broad base of implantation, an irregular, friable surface; it shows areas of necrosis and hemorrhage. Fig. 21.19

21. Fig. 21.20. Colonic adenocarcinoma is an infiltrative tumor composed from tumoral glands. Fig. 21.20

22. Acute diffuse purulent apendicitis From cases of the Pathology Department - U.M.F. “Gr. T. Popa” Iasi Fig. 21. 21. Diffuse acute purulent inflammation of the appendix is caused by apendicular lumen obstruction, ischemia and mucosal ulceration. In acute purulent apendicitis: (1) purulent exudate in the lumen; (2) mucosa is ulcerated; (3) purulent exudate involves the entire apendicular wall up to mesothelial tissue and serosa; (4) serosa is covered by fibrino-purulent exudate (localized peritonitis).