Early Gastrc Carcinoma- Dr. Sattwik Acharya.pptx

This academic presentation by Dr. Sattwik Acharya (PGY-1, Dept. of General Surgery, MKCG MCH, Berhampur) provides a detailed and visually structured overview of early gastric carcinoma (EGC) — its definition, classification, diagnosis, and management, with emphasis on modern endoscopic advances.
Key highlights include:
Epidemiology & Risk Factors: Global and regional distribution, dietary, infectious, and genetic factors influencing gastric cancer incidence.
Definition & Classification: Detailed explanation of early gastric cancer (T1a/T1b) with survival data, and review of Borrmann, Lauren, Vienna, Paris, and Japanese classifications.
Clinical Features & Diagnosis: Focused discussion on diagnostic modalities such as white-light endoscopy, chromoendoscopy, narrow-band imaging (NBI), endoscopic ultrasonography (EUS), and Systematic Alphanumeric Coded Endoscopy (SACE).
Therapeutic Approaches: Stepwise presentation of endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) techniques, indications, complications, and surveillance protocols.
Recent Advances: Overview of image-enhanced endoscopy (BLI, LCI), confocal and multiphoton microscopy, molecular subtyping, and AI-assisted diagnostic systems, as well as innovations in endoscopic dissection techniques.
Overall, this PDF serves as a comprehensive and updated teaching resource on the diagnosis and minimally invasive management of early gastric carcinoma, integrating classical knowledge with recent technological and molecular insights.

1. Early Gastric Carcinoma Dr. Sattwik Acharya PG Y-1 Resident (Unit VI) Department of General Surgery MKCG MCH, Berhampur

2. Management Gastric Carcinoma Clinical Features & Diagnosis Recent Advances 01 Early Gastric Carcinoma Classification 02 03 04 05 06 Contents

3. Fifth leading cause of cancer worldwide Fourth leading cause of cancer deaths worldwide Leading cause of infection related cancer mortality Predominantly affects older adults (over 70 years) Tumour site shifting from distal stomach to proximal (cardia), primarily linked to smoking and alcohol abuse Gastric Cancer Ref : Sung H, Ferlay J, Siegel RL, et al. Global cancer statistics 2020: GLOBOCAN estimates.  CA Cancer J Clin  2021;71:209. Sung H, Siegel RL, Rosenberg PS, Jemal A. Emerging cancer trends in young U.S. adults.  Lancet Public Health 2019;4:e137.

4. Highest incidence rates – Eastern Asia Andean regions of South America Eastern Europe A majority (over 70 percent) of gastric cancers occur in resource-limited countries Regional Distribution Ref : Global Cancer Observatory. IARC, WHO. He Y, Wang Y, Luan F, et al. Chinese and global gastric cancer burden, 1990–2019.  Cancer Med  2021;10:3461.

5. Risk Factors Nutritional Risk Factors: High salt and nitrate intake – damage mucosa Low vitamin A and C consumption – protective factors Poor food preparation methods (smoking, salt curing) Lack of refrigeration Contaminated drinking water (well water) Lifestyle Risk Factors: Cigarette smoking

6. Risk Factors Infectious agents : Helicobacter pylori, Epstein-Barr virus Exposure to radiation History of gastric surgery for benign ulcers (2-6% risk) Male sex (2:1) Genetic factors (1-3% risk), including: Type A Blood Family history of gastric cancer

7. Definition of Early Gastric Carcinoma Ref : Japanese Gastric Cancer Association, 1998, "Japanese classification of gastric carcinoma—2nd English edition" Early gastric cancer is defined as adeno-carcinoma limited to the mucosa (T1a) and submucosa (T1b) of the stomach, regardless of lymph node involvement . 5-year survival:  >90%  if detected early. 99% if confined to the mucosa 96% if the submucosa is invaded

8. EGC Incidence EGC accounts for  15–57%  of gastric cancers globally Regional Variations in EGC Japan : EGC rates increased from 15% to 57% with nationwide screening Korea : EGC comprises  25–30%  of gastric adenocarcinomas U.S. & Europe : EGC accounts for  15–21%  of gastric cancer cases Factors Behind Regional Differences Variability in  pathology practices  and histologic diagnosis Greater adoption of  screening programs  in East Asia

9. 1. Borrmann Classification  Focus:   Gross macroscopic appearance  of advanced gastric carcinoma Classification Types: Polypoid Fungating with raised margins Infiltrative ulcerative (with indistinct borders) Diffuse infiltrative ( Linitis plastica ) Unclassified

10. 2. Lauren Classification  Focus:   Histologic subtype Best for:  Prognosis and understanding pathogenesis Classification Types Intestinal type : Gland-forming, cohesive, often linked to environmental factors Diffuse type : Poorly cohesive/signet ring cells, infiltrative, worse prognosis

11. 3. Vienna Classification  Focus:   Histologic categorization of gastrointestinal epithelial neoplasia Aims to unify Western and Japanese pathology terms Best for:  Pathology reporting and biopsy interpretation Classification

12. 4. Paris Classification  Focus:   Endoscopic appearance  of superficial GI lesions (including EGC) Defines type 0 (superficial lesions): 0-I : Protruded (elevation > 3 mm) 0-IIa : Slightly elevated (elevation < 3 mm) 0-IIb : Flat 0-IIc : Slightly depressed 0-III : Excavated Best for:  Endoscopic diagnosis and treatment planning Classification

13. Paris Classification of EGC

14. Upper row: white light only Lower row: same lesions under chromoendoscopy Paris Classification of EGC

15. 5. Japanese Classification  Macroscopic EGC Types (Type 0): Type I : Protruded Type II : Superficial IIa : Elevated IIb: Flat IIc : Depressed Type III : Excavated Also includes: Histologic type (differentiated vs. undifferentiated) Depth of invasion (mucosa/submucosa) Lymphovascular invasion, nodal status Best for:  Surgical and oncologic planning in Japan and East Asia Classification

16. Japanese Classification of EGC Ref : Japanese Gastric Cancer Association. Japanese classification of gastric carcinoma: 3rd English edition. Gastric Cancer   14 , 101–112 (2011).

17. Type 0 - I Type 0 - II Type 0 - III a b c

18. Clinical Features Often asymptomatic Presentation : Dyspepsia Nausea Bloating Anorexia Alarm signs : Weight loss Anemia GI bleeding

19. Endoscopic Diagnosis White Light Endoscopy (WLE) Chromoendoscopy Narrow Band Imaging (NBI) Endoscopic Ultrasonography (EUS) Systematic Alphanumeric Coded Endoscopy (SACE)

20. White Light Endoscopy (WLE) Diagnostic accuracy for EGC: 68.9% Limitations: EGC lesions often missed by WLE Ref : J. Zhang et al., BMC Gastroenterology, 2011, Vol. 11, pp. 135-141

21. Chromoendoscopy Involves applying stains or dyes during endoscopy Highlights subtle mucosal surface elevation differences and color changes Dyes Used in Gastric Carcinomas: Methylene Blue, Indigo Carmine, Congo Red Magnifying chromoendoscopy (x100 – x150) reveals: Surface mucosal patterns Capillary structures

22. A : Combined flat and elevated lesion with an unclear border at the lower body of the stomach B : Endoscopic view after acetic acid was sprinkled. C : Endoscopic view after indigo carmine was additionally sprinkled. D : Endoscopic view after the lesion was washed with clean water. Borders are distinct. Differentiated Adenocarcinoma

23. A : A flat discoloured lesion with an unclear border at the lower body of the stomach. B : Endoscopic view after acetic acid was sprinkled. C : Endoscopic view after indigo carmine was additionally sprinkled. D : Endoscopic view after the lesion was washed with clean water. Borders are still indistinct. Undifferentiated Adenocarcinoma

24. Chromoendoscopy Advantages: Widely available technique Simple, inexpensive and safe method Limitations: Time-consuming Interpretation of findings are not always straight forward

25. Narrow Band Imaging (NBI) An equipment-based image-enhanced endoscopy technique Uses blue and green narrowband lights to highlight tissue features Detects irregular microvascular patterns (MV) Absence of microsurface patterns (MS) Purpose: Enhances contrast between the epithelial surface and underlying vascular patterns Helps differentiate small gastric cancers (<1 cm) from gastritis Enhances margin determination for endoscopic therapy

26. Narrow Band Imaging (NBI)

27. Narrow Band Imaging (NBI) A: White-light endoscopy image B: Conventional magnification method with narrow-band imaging (NBI) image C: Near-focus mode with NBI image.

28. Narrow Band Imaging (NBI) VS classification using NBI V  microvascular pattern: Regular/Irregular/Absent S   microsurface pattern: Regular/Irregular/Absent Diagnostic criteria for gastric cancer : Irregular microvascular pattern with a demarcation line Irregular microsurface pattern with a demarcation line Diagnosis : Cancer if either or both criteria are met Non-cancer if neither criterion is met 97% of early gastric cancers meet these criteria

29. NBI vs Chromoendoscopy vs WLE NBI is more effective than chromoendoscopy and conventional endoscopy Accuracy rates: WLE: 68.9% Chromoendoscopy: 91% NBI: 93.6% Ref : J. Zhang et al., BMC Gastroenterology, 2011

30. Endoscopic Ultrasonography (EUS) Uses 20 MHz catheter-based miniprobes - Higher frequency (instead of 12 MHz) Diagnoses depth of tissue invasion Assesses submucosal vasculature preoperatively to predict intraoperative bleeding risk

31. A : EUS showing normal layers of gastric wall, with the five-layered echo pattern being clearly visible (arrow). B : EUS of early gastric cancer (T1a), showing a focal thickening area confined to layers 1 and 2 (dotted line). C : EUS image of advanced gastric cancer (T3); the tumor involves all layers and extends beyond the the outermost layer of the gastric wall (arrow). D : EUS showing a metastatic lymph node (dotted line).

32. Systematic Alphanumeric Coded Endoscopy (SACE) Complete examination of the UGI tract Simple, sequential and systematic overlapping photo-documentation of 8 regions and 28 areas.

33. Endoscopic Therapy Lymph Node (LN) Metastasis Rates in EGC: 3% for intramucosal carcinoma 20% for submucosal carcinoma Indications for Endoscopic Therapy: Lesions with negligible risk of lymph node metastasis Ref : M. Sasako et al., 1993 (pages 139–146)

34. Endoscopic Therapy EMR (Endoscopic Mucosal Resection): Strip Biopsy Method Endoscopic Resection with a Cap-fitted Endoscope (EMR-C) Endoscopic Resection with Band Ligation (EMR-L) ESD (Endoscopic Submucosal Dissection)

35. Indications for EMR A differentiated elevated intramucosal cancer < 2 cm A differentiated depressed intramucosal cancer < 1 cm without ulceration Invasion limited to mucosa on the basis of EUS No lymphatic or vascular involvement Ref : Sabiston Textbook of Surgery, 21 st Ed, Page: 1226

36. Endoscopic Mucosal Resection (EMR) Initial: Inject saline under lesion to lift tissue for snaring Later improvements included: Use of various injection solutions like hypertonic saline with dilute epinephrine Addition of cap-fitted pan-endoscopes Use of variceal ligation devices to capture lesions

37. Endoscopic Mucosal Resection (EMR)

38. EMR by Strip Biopsy 1 : Saline is injected into the submucosal layer and the area is elevated. 2 & 3 : The top of the mound is pulled upward with forceps and the snare is placed at the base of the lesion. 4 : Electrosurgical current is applied through the snare to resect the mucosa and the lesion is removed. Ref : Sabiston Textbook of Surgery, 21 st Ed, Page: 1226

39. EMR-C vs EMR-L

40. EMR Disadvantages: Cannot resect large tumors (>1.5 cm) en bloc Piecemeal resection – difficult to assess completion/curability Residual tumor incidence ranges from 2.3% to 35% En Bloc Resection Piecemeal Resection

41. Endoscopic Submucosal Dissection (ESD) Involves dissecting directly along the submucosal layer using a high-frequency knife Indications for ESD include: Differentiated intramucosal cancers without ulcer, regardless of tumor size Differentiated intramucosal cancers under 3 cm with ulcer Differentiated minute invasive submucosal (SM1) cancers under 3 cm, with invasion less than 500 μ m below muscularis mucosa Undifferentiated intramucosal cancers under 2 cm without ulcer

42. A: Gastric cancer lesions. B: Injection of a mixture of sodium hyaluronate to highlight the submucosa, followed by circumferential marking made by needle knife. C: Circumferential mucosal incision by the Insulation-tipped (IT) knife. D: Complete dissection of the submucosal layer using IT knife. E: Postoperative wound after an en bloc resection. F: Specimen processing Ref : Zheng X, Zuo N, Lin H, et al. Margin diagnosis for ESD of early gastric cancer using multiphoton microscopy.  Surg Endosc  2020;34. doi:10.1007/s00464-019-06783-1. ESD

43. ESD Disadvantages: Increased risk of perforation Increased risk of bleeding Complications treatable via endoscopy

44. Surveillance Post EMR/ESD EMR: Annual endoscopic surveillance to ensure early detection of metachronous cancer (5.9% incidence) ESD: Annual endoscopic surveillance + Abdominal CT or EUS every 6 months for at least 3 years to detect lymph node or distant metastasis

45. Limited Surgical Resection Gastrotomy with full-thickness mural excision for accurate pathologic assessment of T status Aided by intraoperative gastroscopy to localize the tumor Formal lymph node dissection is not required for these patients.

46. Gastrectomy Lower, upper or total gastrectomy with D1 or D2 LN dissection. D1 dissection: Limited to perigastric lymph nodes. D2 dissection: Includes D1 plus nodes along hepatic, left gastric, celiac, splenic arteries and splenic hilum (stations 1-11).

47. Procedure Selection

48. Recent Advancements - Diagnosis Image-Enhanced Endoscopy (IEE) Blue Laser Imaging (BLI):  Provides brighter and sharper imaging than NBI, especially for distant views. Linked Color Imaging (LCI):  Enhances subtle color differences in mucosa, improving detection of flat or pale lesions often missed by WLE. Confocal Laser Endomicroscopy (CLE) In vivo histological examination using fluorescent dyes (e.g., fluorescein). Allows for real-time "optical biopsy", reducing unnecessary physical biopsies. Multiphoton Microscopy (MPM) A novel technique that utilizes nonlinear optics to image tissue at subcellular resolution. Provides  label-free imaging , distinguishing cancerous margins without dyes. Particularly promising for  margin assessment after ESD

49. Recent Advancements - Diagnosis Serological and Non-Invasive Markers Serum pepsinogen I/II ratio ,  Helicobacter pylori antibodies , and  gastrin-17  to stratify gastric cancer risk. MicroRNAs (e.g., miR-21, miR-196a)  are under study as potential early diagnostic markers in blood or gastric juice. Molecular Subtyping EBV-positive ,  microsatellite instability ,  chromosomal instability and  genomically stable subtypes  offer therapeutic targets and prognostic value.

50. Artificial Intelligence (AI) in Endoscopy AI-integrated CAD systems can: Detect subtle  EGC lesions  missed by human eyes. Classify lesions as  neoplastic or non-neoplastic  in real time. Predict  depth of invasion  and  histology subtype  with high accuracy.

51. Therapeutic Advancements Modern improvements in ESD: Traction methods : e.g., clip-with-line, rubber band methods Specialized knives : scissors-type knives for fibrotic lesions Haemostatic techniques : advanced coagulation forceps and haemostatic powders Hybrid ESD  combines mucosal incision with snaring in difficult locations. Underwater ESD  improves visualization and dissection in collapsed lumens or fibrotic tissue. Third Space Endoscopy: Techniques like  submucosal tunnelling dissection  used for subepithelial or technically challenging lesions.

52. THANK YOU