1. Faculty of Allied Medical Sciences Histopathology and Cytology MLHC-201

2. THE PATHOLOGY OF THE GASTRO INTESTINAL TRACT Supervision Prof.Dr.Noha Ragab

3. outcomes By the end of this lecture, the student will be able to understand the pathology of gastrointestinal tract and oral cavity

4. THE PATHOLOGY OF THE ORAL CAVITY

5. Benign Neoplasms: PAPILLOMA: Squamous papilloma is a benign, exophytic epithelial neoplasm composed of branching fronds of squamous epithelium with fibrovascular cores.

7. Squamous Cell Carcinoma (SCC) SCC is the most common malignant tumor of the oral mucosa. Pathology: SCC of the oral cavity is similar to the same tumor in other sites.

8. ULCERS OF THE ORAL CAVITY 1.Dental ulcer: traumatic ulcer by a sharp tooth 2.Aphthous ulcer: very common Painful, recurrent, solitary or multiple, small ulcers. The lesion consists of a shallow ulcer covered by a fibrinopurulent exudate and inflammatory infiltrate. 3.Tuberculous ulcer: an ulcer with undermined edges and caseous floor. It most commonly develops at the tip of the tongue. Coughed sputum containing bacilli leads to infection of the tongue 4.Malignant ulcer: the ulcer edges are raised and everted, the floor of ulcer is rough, necrotic and the base of the ulcer is indurated.

9. Salivary Glands

10. ENLARGEMENT: Unilateral enlargement of major salivary glands is usually caused by cysts, stones, inflammation, or neoplasms. Bilateral enlargement is due to inflammation (mumps, Sjögren syndrome), granulomatous disease (Saroidosis), or diffuse neoplastic involvement (leukemia or malignant lymphoma).

11. SIALOLITHIASIS: Stones occur in salivary gland ducts, mostly in the sub-mandibular gland. The most important consequence of stone formation is duct obstruction, often followed by inflammation distal to the occlusion.

12. MUMPS Acute viral parotitis. Mainly affecting children, rare in adults Eitiology: Mumps virus, transimitted by droplet infection. Incubation period: 2-4 weeks

14. Benign Salivary Gland Neoplasms

15. A- Pleomorphic Adenoma (Mixed Tumor) Pathology: Pleomorphic adenoma is a slowly growing, painless, movable, firm mass that has a smooth surface. Microscopically: the tumors show epithelial tissue intermingled with myxoid or chondroid areas, reflecting a mixture of epithelial and mesenchymal components.

17. Malignant Salivary Gland Tumors

18. Mucoepidermoid Carcinoma: Mucoepidermoid carcinoma is a malignant salivary gland tumor composed of a mixture of neoplastic epidermoid cells, mucus-secreting cells, and epithelial cells of an intermediate type. Grossly: Mucoepidermoid carcinoma grows slowly and presents as a firm painless mass. Microscopically: Tumors form irregular solid, duct-like and cystic spaces, which include squamous cells, mucus- secreting cells, and intermediate cells.

20. Adenoid Cystic Carcinoma: Adenoid cystic carcinoma is a slowly growing salivary gland malignancy with a tendency to invade locally and recur after surgical resection.

21. Pathology: The tumor cells are small, have scant cytoplasm, and grow in solid sheets or as small groups, strands, or columns. Within these structures, the tumor cells interconnect to enclose cystic spaces, resulting in a solid, tubular or cribriform (sieve-like) arrangement.

23. ESOPHAGUS

24. Congenital disorders: Tracheosophageal fistula: congenital connection between the esophagus and trachea Esophageal webs: web-like protrusions of the esophageal mucosa into the lumen Achalasia: failure of the lower esophageal spincter (LES) to relax with swallowing

26. Esophageal varices: Diltated submucosal veins in the lower third of the esophagus, usually secondry to portal hypertension. Cause: liver cirrhosis Clinically: massive hematemesis when ruptured Complication: potentially fatal hemorrhage

28. Esophagitis

29. Gasteroesophageal reflux disease (reflux esophagitis) Esophageal irritation and inflammation due to reflux of gastric secretion into the esophagus. Clinically: heart burn and regurgitation Complications: Bleeding Stricture Barrette esophagus

30. ESOPHAGEAL CARCINOMA

31. Squamous cell carcinoma (SCC) of esophagus SCC is the most common type of esophageal cancer Risk factors: Heavy smoking Alcohols Achalasia Clinical presentation: At the beginning it may be asymptomatic Then progressive dysphagia Weight loss & anorexia Bleeding

32. Adenocarcinoma (AC) of esophagus: Arise in the distal part of the esophagus Associated with Barrett esophagus (Metaplasia of the squamous esophageal mucosa to columnar type because of chronic exposure to gastric secretions)

34. Questions: Complete: 1-Adenoid Cystic Carcinoma is……………… 2- Clinical presentation of scc is……….. 3- Bilateral enlargement is due to………….. 4- Adenoid cystic carcinoma is ………….with a tendency to………………….

35. Assignments Causes of Epistaxis محمد فوزى خضر بشاره محمود محمد رمضان على العربى مروة أشرف محمد أحمد مروة حسن صقر مروة يونس رمضان ميرنا ابراهيم على نادية محمد سعد

36. Thank You