1. Large Bowel

2. Amoebic Colitis
Multiple ulcers
Trophozoites with erythrophagocytosis

3. Amoebic Colitis Complications
Perforation
Hemorrhage
Liver abscess

4. Ulcerative Colitis After fixation in formalin Gross features of UC
Pseudopolyps

5. Ulcerative Colitis Mucosal acute inflammation (non-specific)
Crypt abscess

6. Ulcerative Colitis : complications
Lower GI hemorrhage
Toxic megacolon

7. Diverticular Disease
Diverticulitis
Diverticulosis

8. Colonic Polyps Adenomatous Hyperplastic Hamartomatous
Retention (juvenile)
Inflammatory (pseudo)

9. Rectal Polyps
Hyperplastic polyp
Retention polyp
(Juvenile polyp)

11. Colonic polyp
Adenomatous polyp

12. Adenomatous Polyp Tubular adenoma
H & E
H & E
Tubular adenoma

13. Dysplasia in adenoma

14. Villous Adenoma

15. Villous = Hairy
Under-water view

16. Histopathology of villous adenoma
H&E
tumor VS normal mucosa

17. Polyposis Coli
Early lesions in a case of FAP

18. Dukes classification of
CA rectum

19. Staging of CA colon
Astler-Coller system

20. Carcinoma of Rectum
A-P resection specimen

21. Carcinoma of Colon
H & E
Adenocarcinoma
Invasive tumor

22. Tumor necrosis

23. Tumor infiltration

24. Lymphatic invasion

25. Vascular invasion
Venous permeation

26. Nodal metastasis

27. Metastatic Carcinoma to the Liver