upper gastrointestinal lecture slide ppt

CI UGI Lecture

1. Surgical pathologies of the gastrointestinal tract 5/25/2024 By Dr.Diribe Bedasa, general surgeon 1 For C I medical students

2. Topics 1. Stomach peptic ulcer disease neoplasms of the stomach 2. Colorectal cancer 3. Benign conditions of the anorectum hemorrhoids anorectal abscesses fistula inano fissure inano 4. Acute abdomen small bowel obstruction large bowel obstruction Appendicitis 5/25/2024 2

3. Anatomy 5/25/2024 3

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10. Peptic ulcer disease(PUD) Peptic ulcer –defect on gastric or duodenal mucosa that may extend to sub mucosa or deeper Imbalance between mucosa defense and acid/pepsin injury One of the most common GI disorders Mortality increase in elderly –NSAIDS and Aspirin commonly used duodenum, stomach or jejunum of pt with ZES 5/25/2024 10

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12. PUD…  Etiology H.pylori infection NSAIDS use Alcohol Smoking Physiologic stress (head injury, burn) hypersecretory state 5/25/2024 12

13. PUD… H.Pylori Gram negative helical bacteria Colonizes approx. ½ of world population Causes PUD and may predispose to gastric cancer & MALT Identified in 95% of duodenal ulcer and 70% gastric ulcer 5/25/2024 13

14. H.Pylori & PUD H.Pyori can be identified in pts with antral gastritis Eradication of H.pylori with antimicrobial leads to ulcer healing Re-infection is associated with ulcer recurrence 5/25/2024 14

15. NSAIDS Accounts for many H.pylori negative ulcer Prevalence in chronic users 25% (15%GU & 10% DU) Higher complication rates Inhibit COX enzyme → ↓↓↓ prostaglandin production ↓↓ bicarbonate production ↓↓ mucus gel layer 5/25/2024 15

16. PUD…. Smoking Diminishes gastric mucosal defense mechanism Continued smoking attenuates ulcer healing and increased recurrence Alcohol Direct mucosal injury and acid hypersecretion 5/25/2024 16

17. Pathogenesis “ no acid no ulcer” is a misconception; **excessive acid production is one factor PUD, not the only cause Integrity of upper GI mucosa is dependent on the balance b/n hostile and protective factors. 5/25/2024 17

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19. Types of gastric ulcer 5/25/2024 19 Johnson’s classification Type I - lesser curve, incisura Type II - body of stomach and duodenal ulcer Type III - prepyloric Type IV - high on lesser curve, near GEJ Type V- NSAID related, anywhere in the stomach

20. Clinical assessment H/P Epigastric pain * Ingestion of NSAID & others Nausea / vomiting Mild hemorrhage – hematemesis, melena Acute complications no physical finding in uncomplicated PUD 5/25/2024 20

21.  Alarm signs Weight loss Dysphagia Bleeding Anemia jaundice 5/25/2024 21

22. Investigation CBC, blood group Electrolyte, RFT……especially in patients with bleeding Tests for H.pylori Endoscopy: demonstrates ulcer and permits biopsy 5/25/2024 22

23. Complications  Bleeding The most common and most lethal complication of PUD 27-46% of all cases of upper GIH 40% of ulcer associated deaths are due to hemorrhage Location:- DU  post. wall of duodenal bulb(from gastro duodenal & superior pancreatico duodenal arteries ) - GU along the lesser curvature(from branches of left gastric artery) 5/25/2024 23

24. Hematemesis & melena the most common clinical finding Hematochezia in massive UGIB Weakness, dizziness, syncope or postural hypotension 5/25/2024 24

25. Perforation; -second most common complication - usually presents as an acute abdomen with symptoms and signs of peritonitis 3 phases of peritonitis in perforated PUD chemical peritonitis Intermediate phase Bacterial peritonitis 5/25/2024 25

26. Compl .. Gastric outlet obstruction(GOO) occurs in 5% of patents with PUD. usually due to duodenal or pre pyloric ulcer disease -acute -chronic (from cicatrix). Pain or discomfort is common. non bilious vomiting Weight loss A succession splash hypokalemic hypochloremic metabolic alkalosis with paradoxical aciduria dehydration. 5/25/2024 26

27.  Risk of Gastric cancer Intractable pain 5/25/2024 27

28. Management of PUD: Medical Triple therapy: PPI, Amoxicillin, clarithromycin Sequential therapy: PPI plus Amoxicillin for 5 days followed by PPI, clarithromycin and Tinidazole for additional 5 days. Bismuth based quadruple therapy Levofloxacin based triple therapy Avoid aggressive factors 5/25/2024 28

29. Surgical management of PUD - done for complications -indications; - bleeding, - perforation, -obstruction, - intractability and -suspected malignancy 5/25/2024 29

30. Gastric tumors May arise from the tissues of the mucosa (adenocarcinoma), connective tissue of the stomach wall (gastrointestinal stromal tumors, GISTs) neuroendocrine tissue (carcinoid tumors) the lymphoid tissue (lymphomas) 5/25/2024 30

31. Gastric tumors… primary gastric tumors 5/25/2024 31

32. primary malignant neoplasms most common primary malignant neoplasm's are : Adenocarcinoma-95% Lymphoma-4% Malignant GIST-1% Rare primary malignant neoplasm's are: Carcinoid Angiosarcoma angiosarcoma , Carcinosarcoma squamous cell carcinoma 5/25/2024 32

33. Secondary malignant gastric neoplasms Hematologic spread e.g. melanoma, breast ca. direct extension of cancer from nearby structures: Colon Pancreas Peritoneal seeding e.g. ovary ca , appendiceal ca ). 5/25/2024 33

34. Gastric cancer, adenocarcinoma Epidemiology -Gastric cancer is the fourth most common cancer in the world. -Second most common cause of cancer death - Approximately 10% of cancer-related deaths worldwide - 870,000 new cases and 650,000 deaths per year - Over 70% occur in developing countries Geographic variation -Highest death rates in East Asia, South America, and Eastern Europe (Japan, korea , chilli …) 5/25/2024 34

35. Epidem… -Median age at diagnosis is 65 years (40-70) -Extremely rare below 30 years & increases rapidly thereafter -Male : Female= 2:1 - Blacks are affected twice as whites -High incidence in low socioeconomic status -The estimated 5-year survival rate is 27% -Over all decline in distal stomach cancer 5/25/2024 35

36. Etiologies It is complex and multifactorial, involving a combination of genetic environmental, and infectious risk factors. 5/25/2024 36

37. Risk factors 5/25/2024 37 Nutritional Low fruit and vegetable Salted meat/fish High nitrate High complex carbohydrate Environmental Poor food preparation Lack of refrigeration contaminated drinking water Smoking Medical H-pylori Gastric atrophy Pernicious anemia Polyps Menetrier disease…5-10% EBV Prior gastric surgery…10% Other Low socio-economic Male gender

38. Risk factors…… 5/25/2024 38 Diet High salted meat/fish and pickled foods Damage stomach mucosa and increases the susceptibility to carcinogenesis High nitrate, N-nitrosamine(carcinogen) Intake of green, leafy vegetables and citrus fruits, which contain antioxidants such as ascorbate and beta-carotene is protective Smoking Increases risk by 60% in men and 20%in women

39. 5/25/2024 39 Genetics Commonly affected genes are(deletion or suppression of P53), ( over expression of COX 2) and CDH1 gene Hereditary diffuse gastric cancer(CDH1 gene mutation) -inactivates e-cadherin (cell adhesion molecule) -2 of more gastric cancer cases in the 1 st /2 nd degree relatives with age<50 -80% increased risk Lynch syndrome(HNPCC) – intestinal type and 10% higher risk Familial adenomatous polyposis /FAP – APC mutation & 10% increased risk Li- fraumeni syndrome – P53 gene mutation

40. 5/25/2024 40 Helicobacter pylori Classified as definite carcinogen Associated with 3x increases risk in developing adenocarcinoma Triggers inflammation at the corpus mucosa that results in atrophy and intestinal metaplasia Alterations depend on both the presence of bacterial proteins and the host immune response The cagA strain causes more mucosal inflammation and thus a higher risk of gastric cancer than strains lacking these genes

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43. Pernicious anemia Destruction of parietal and chief cells by autoimmune reaction. Achlorhydria that accompanies this condition favors bacterial proliferation, which generates carcinogenic nitrosamines from nitrates Blood group A 20% incidence Mostly associated with diffuse gastric cancer 5/25/2024 43

44. Epstein–Barr virus (EBV) Detected in 2-16% of gastric adenocarcinoma Role in gastric carcinogenesis is not yet established Higher frequency in tumors of the proximal and Male predominance Previous gastric surgery Occur after ten years of surgery Overall risk is 3-10% Pathogenesis related to bile reflux , achlorhydria and atrophic gastritis, 5/25/2024 44 EBV-associated gastric cancers have distinct clinicopathologic characteristics, including male predominance, preferential location in the gastric cardia or postsurgical gastric stump, lymphocytic infiltration, a lower frequency of lymph node metastases, perhaps a more favorable prognosis [ 59,61,66-69 ], and a diffuse type of histology in most [ 59,61,62,69,70 ] but not all [ 65-67 ] series. (See  "Pathology and molecular pathogenesis of gastric cancer" .)

45. CONT… Increased risk : Familial polyposis Gastric adenomas Hereditary non polyposis Colorectal ca Atrophic gastritis, intestinal metaplasia and dysplasia Previous gastrectomy or GJ (>10 yrs ) Diet(high in nitrates ,salts, fat-high ) Tobacco use H-Pylori infection- definite carcinogen 3x risk of gastric ca 5/25/2024 45

46. Cont… patients with pernicious anemia Blood group A Family history of gastric ca Environmental factor intestinal form of gastric ca Mutation in p53 and cox-2 gene E-cadherin mutation Prophylactic total gastrectomy should be considered in patients with the mutations Decreased risk : Aspirin Diet (high in fresh fruit and vegetables) Vitamin C 5/25/2024 46

47. Premalignant conditions of the stomach Atrophic Gastritis Gastric polyps Intestinal Metaplasia Benign Gastric Ulcer Ménétrier’s Disease 5/25/2024 47

48. Premalignant conditions of the stomach Atrophic gastritis : -the most common precancerous lesion is -Inflammation with mucosal thinning, gland atrophy and metaplasia -Risk of developing adenocarcinoma is increased by 6 fold *H. pylori infection is incriminated Has three patterns: Autoimmune (acid secreting, proximal stomach) Hypersecretary (distal stomach) Environmental (junction of oxynitic and anthral mucosa) 5/25/2024 48

49. Gastric polyps: incidental finding  Neoplastic - adenomatous polyp- premalignant - fundic gland polyps- not premalignant, but ?FAP  Non neoplastic - Hyperplastic polyps- if >2cm may harber dysplasia - hamartomatous polyps - Inflammatory polyps - heterotrophic polys 5/25/2024 49 negligible malignant potential

50. cont’d Intestinal metaplasia- precursor Gastric cancer occurs in an area of intestinal metaplasia Treatment of H pylori is reasonable Benign gastric ulcer All gastric ulcers are cancer until proven otherwise Benign ulcers are resected for non-healing 5/25/2024 50

51. CONT… Gastric remnant cancer : Gastric ca can develop in the gastric remnant Usually years ( >10yrs )after gastrectomy for PUD Arise in the area of chronic gastritis, metaplasia and dysplasia Often near the stoma Its prognosis is similar to gastric ca 5/25/2024 51

52. Ménétrier’s Disease - The mucous cell hyperplasia …enlarged gastric folds -carry a 5% to 10% risk of adenocarcinoma. - Periodic surveillance EGD 5/25/2024 52 is a protein-losing enteropathy, along with giant hypertrophy of gastric mucosal folds. It is a precancerous condition.

53. Pathology Dysplasia(Intra-epithelial neoplasia) Is the universal precursor of gastric adenocarcinomas Severe widespread or multifocal dysplasia-consider gastric resection Localized severe dysplasia-consider EMR Patients with mild dysplasia should be followed with endoscopic biopsy surveillance and H.pylori eradication 5/25/2024 53

54. Classification No agreement on how gastric tumors should be classified. WHO-developed a universally accepted classification  Pathohistological classification is based on macroscopic growth pattern depth of invasion Early or advanced Bormann classification The Ming classification two types—expanding (67%) and infiltrative (33%). 2. Histologic classification WHO Lauren 5/25/2024 54

55. 1. Macroscopic growth pattern Early gastric ca : Defined as adenocarcinoma limited to the mucosa and submucosa Of the stomach. Common in gastric ca endemic areas where aggressive surveillance has been established 10% of cases have lymph node metastasis 70% are well differentiated and the rest are poorly differentiated 5/25/2024 55

56. Cont… Early gastric ca(types and subtypes): Type I- exophytic lesion extending in to the gastric lumen Type II-superficial variant IIA –elevated lesions with a height no more than the thickness of the adjacent mucosa IIB-flat lesions IIC-depressed lesions with an eroded but not deeply ulcerated appearance Type III-excavated lesions that may extend in to the muscularis propria without invasion of this layer by actual cancer cells 5/25/2024 56

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58. Macroscopic growth pattern ( Gross morphology) Advanced gastric ca Four gross forms of gastric ca ( Bormman ) Polypoid Fungating intraluminal Ulcerative Scirrhous in the wall of the stomach  Scirrhous tumor: - Linitis plastica poor prognosis technically resectable with total gastrectomy 5/25/2024 58 It refers to involvement of muscularis mucosa and/or serosa with or without involvement of lymph nodes

59. Histologic classification Lauren ( 1965 )….. Commonly used Intestinal types…53% Diffuse types…33% Unclassified…14% 5/25/2024 59

60. 5/25/2024 60 Intestinal Environmental Gastric atrophy M>F Older age Gland formation Hematogenous spread Better prognosis Diffuse Blood group A Familial F>M Younger age Poorly differentiating signet ring cells Trans mural, lymphatic spread

61. Histologic classification WHO (2010): most detailed, universally accepted Adenocarcinoma Tubular (most common) Papillary Mucinous Signet-ring Adenosquamous carcinoma Squamous cell carcinoma Small cell carcinoma Undifferentiated carcinoma others 5/25/2024 61

62. Cont… Location of the primary tumor is important in planning operation Currently, the distribution of primary ca is: Distal ….40% middle….30% Proximal…30% 5/25/2024 62

63. The most important prognostic indicators are: -Histology -Lymph node involvement -Depth of invasion -Tumor grade 5/25/2024 63

64. Pathological staging: The most widespread system for staging –TMN staging system Prognosis is related to pathological staging Developed by American joint committee on cancer and the international union against cancer

65. Cont’d Tis : Carcinoma in situ:intraepithelial tumor without invasion of lamina propria T1 : tumor invades lamina propria or sub mucosa T2 : tumor invades muscularis propria T3 : tumor penetrates serosa without invasion of adjacent structures T4 : tumor invades adjacent structures 5/25/2024 65

66. N:regional lymph node: N0-no regional LN metastasis N1-1-6 lymph nodes N2-7-15 lymph nodes N3->15 lymph nodes M:distant metastasis Mo-no distant metastasis M1-distant metastasis 5/25/2024 66

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68. Spread of Gastric Ca Distant spread is unusual before the disease spreads locally & distant metastasis is uncommon in the absence of LN metastasis Direct spread to adjacent structures (pancreas, transverse colon, esophagus, liver) Lymphatic spread may be extensive supra clavicular - Troisier`s sign(Virchow`s nodule) 5/25/2024 68

69. Spread … Blood stream :- liver, lung, bone & uncommon in the absence of nodal involvement Trans peritoneal spread Common mode of spread once tumor has reached serosa of stomach & indicates incurability Can give ascites 5/25/2024 69

70. Cont’d Tumor cells gravitate to pelvis ( Blummer`s shelf ) Ovary ( Krukenberg`s tumors) Umbilicus (Sister Joseph`s nodule) 5/25/2024 70

71. Gastric lymphoma 5/25/2024 71  4% of gastric ca -Stomach is the commonest site of primary GI lymphomas -Mainly non- Hodgkin lymphomas(>95%) -Most are B cells type -High grade(50%) or low grade(50%) -Normal stomach is devoid of lymphoid tissue— * H.pylori infection—chronic gastritis--MALT

72. GIST : Gastrointestinal stromal tumors 5/25/2024 72 Arise from ICC, interstitial cells of Cajal Are distinct from Leiomyoma and leiomyosarcoma Typically hematogenous route Prognosis depends on tumor size and mitotic count, and metastasis Any lesion >1cm-malignant fashion Tumor markers- CD117 and CD34

73. Evaluation History Clinical Examination Investigations The clinical features of gastric cancer may arise from - local disease, - its complications or - its metastases . 5/25/2024 73

74. HISTORY mostly with advanced stage weight loss decrease food intake due to anorexia and early satiety Abdominal pain (constant, non-radiating) Nausea, vomiting, bloating acute GI bleeding -5% Chronic occult blood loss Dysphagia-common in proximal tumor Paraneoplastic syndromes (thrombophlebitis, acanthosis nigricans , per neuro …)-rare 5/25/2024 74

75. Physical examination usually normal enlarged lymph nodes Metastasis- pleural effusion Aspiration pneumonitis Abdominal mass Liver metastasis Krukenberg‘s tumor of the ovary Sister Joseph's nodule- pathognomonic of advanced disease 5/25/2024 75

76. Laboratory Ix Assists in determining optimal therapy. CBC identifies anemia, which may be caused by bleeding, liver dysfunction, or poor nutrition. -30% have anemia. Electrolyte panels and LFTs are also essential to better characterize patients clinical state. 5/25/2024 76

77. IMAGING STUDIES Abdominal u/s PA-CXR Barium meal endoscopy with biopsy CT and MRI pet scanning 5/25/2024 77

78. Cont’d Indications for endoscopy with or without biopsy: >45years with new onset dyspepsia All patients with dyspepsia and alarm symptoms Family history of gastric ca 5/25/2024 78

79. CONT… endoscopy is gold standard Abd/pelvic CT-scanning with IV or oral contrast- pre op staging EUS - For local staging – 80% EUS- most important in early gastric ca Vs advanced ca PET- scanning- in the evaluation of distal metastasis and most useful with spiral CT( PET-CT) 5/25/2024 79  Endoscopic ultrasonography (EUS) is thought to be the most reliable nonsurgical method available for evaluating the depth of invasion of primary gastric cancers, particularly for early (T1) lesions  Serologic markers  — Serum levels of carcinoembryonic antigen (CEA), the glycoprotein CA 125 antigen (CA 125), CA 19-9 (carbohydrate antigen 19-9, also called cancer antigen 19-9), and cancer antigen 72-4 (CA72 4) may be elevated in patients with gastric cancer [ 65-69 ]. However, low rates of sensitivity and specificity prevent the use of any of these serologic markers as diagnostic tests for gastric cancer.

80. TREAMENT OF GASTRIC CA  surgery Surgical resection is the only curative Rx Goal of resection: Ro resection Proximal, distal and radial Adequate lymphadenectomy Extent of gastrectomy: Standard operation-radical subtotal gastrectomy 5/25/2024 80

81.  chemotherapy radiation therapy Marginal benefit Endoscopic resection: Early gastric ca <3cm-EMR Currently, tumor size <2cm-EMR 5/25/2024 81

82. The end. 5/25/2024 82

83. QUESTIONS? 5/25/2024 83