GASTRIC CA

1. GASTRIC CA Ruanto, M.T., Sabalvaro, D.K., Salac, C.N., Salazar, J. References: Harrison’s Principle of Internal Medicine 17th edition www.cancer.org

2. EPIDEMIOLOGY GASTRIC ADENOCARCINOMA • Decrease incidence and mortality rates for gastric CA during past 75 years (unclear reasons) • Risk: lower > higher socioeconomic classes • Development: • Environmental exposure beginning early in life • Dietary carcinogens

3. EPIDEMIOLOGY PRIMARY GASTRIC LYMPHOMA • Uncommon: <15% of gastric malignancies ~2% of all lymphomas • Stomach – most frequent extranodal site for lymphoma • Increased in frequency during the past 30 days • Detected during the 6th decade of life

4. EPIDEMIOLOGY GASTRIC (NONLYMPHOID) SARCOMA • Leiomyosarcomas & GIST: 1-3% of gastric neoplasms

5. CLINICAL FEATURES ADENOCARCINOMA • Asymptomatic - superficial & surgically curable • insidious upper abdominal discomfort (vague, postprandial fullness to severe steady pain) - extensive tumors • Anorexia with slight nausea • Weight loss, nausea & vomiting - tumors of the pylorus • dysphagia & early satiety - diffuse lesions originating in cardia • No early physical signs • Palpable abdominal mass – long-standing growth, regional extension

6. CLINICAL FEATURES ADENOCARCINOMA • Metastases: • intraabdominal lymph nodes • supraclavicular lymph nodes • Ovary (Krukenberg’s tumor) • Periumbilical region (“Sister Mary Joseph node”) • Peritoneal cul-de-sac (Blumer’s shelf): palpable on rectal or vaginal examination • Malignant ascites • Liver – most common site for hematogenous spread of tumor • Unusual clinical features: migratory thromboplebitis, microangiopathic hemolytic anemia & acanthosisnigrans

7. CLINICAL FEATURES PRIMARY GASTRIC LYMPHOMA • Epigastric pain, early satiety & generalized fatigue • Ulcerations with ragged, thickened mucosal pattern by contrast radiographs GASTRIC (NONLYMPHOID) SARCOMA • Anterior and posterior walls of gastric fundus • most frequently involved • Ulcerate and bleed • Rarely invade adjacent viscera • Do not metastasize to lymph nodes • May spread to liver and lungs

8. DIAGNOSIS • Double contrast radiographic examination • Simplest procedure – epigastric complaints • Helps detect small lesions by improving mucosal detail • Stomach should be distended  decreased distensibility may be the only indication of diffused infiltrative carcimoma • Gastroscopy • Not mandatory if: • Radiographic features are typically benign • Complete healing can be visualized by x-ray within 6 weeks • Follow-up contrast radiograph obtained several months later shows a normal appearance

9. DIAGNOSIS • Gastroscopic biopsy and brush cytology • Should be made as deeply as possible • Recommended in all patients with gastric ulcers  to exclude malignancy • Malignant ulcers must be recognized before they penetrate into surrounding tissues • Rate of cure of early lesions limited to mucosa and submucosa is >80%

10. Staging system for gastric ca

11. Risk factors

12. Reference: Harrison’s Principles of Internal Medicine, 17th ed. www.cancer.org

13. Reference: Harrison’s Principles of Internal Medicine, 17th ed. www.cancer.org

14. Reference: Harrison’s Principles of Internal Medicine, 17th ed. www.cancer.org

15. Reference: Harrison’s Principles of Internal Medicine, 17th ed. www.cancer.org

16. Reference: Harrison’s Principles of Internal Medicine, 17th ed. www.cancer.org

17. Reference: Harrison’s Principles of Internal Medicine, 17th ed. www.cancer.org

18. TREATMENT

19. SURGICAL TREATMENT • Complete surgical removal of the tumor with resection of adjacent lymph nodes • Only chance for cure • Possible in <1/3 of patients • Subtotal gastrectomy – distal carcinomas • Total or near-total gastrectomies – more proximal tumors • Extended lymph node dissection – an added risk for complications, do not enhance survival

20. SURGICAL TREATMENT • Prognosis depends on the degree of tumor penetration into the stomach wall. • Adversely influenced by regional lymph node involvement, vascular invasion, and abnormal DNA content • Probability of survival after 5 years • ~20% for distal tumors • <10% for proximal tumors • Recurrences continuing for at least 8 years after surgery • For patients whose disease is “incurable” by surgery with no ascites or extensive hepatic or peritoneal metastasis: • Resection of the primary lesion should still be offered. • Reduction of tumor bulk – best form of palliation; enhance probability of benefit from subsequent therapy

21. Radiation Therapy • Major role: palliation of pain • Gastric adenocarcinoma is a relatively radioresistanttumor. • Control of tumor requires doses of irradiation exceeding the tolerance of surrounding structures (eg., bowel mucosa and spinal cord). • Survival in the setting of surgically unresectable disease limited to the epigastrium was slightly prolonged when 5-FU was given in combination with radiation therapy. • 5-FU: radiosensitizer

22. Pharmacologic Therapy • Cisplatin + epirubicin & infusional 5-FU or + irinotecan • Complete remissions are uncommon. • Partial responses in 30-50% of cases are transient. • Overall influence on survival has been unclear. • Adjuvant chemotherapy alone following complete resection has only minimally improved survival. • Perioperativetreatment and postoperative chemotherapy + radiation therapy reduce the recurrence rate and prolongs survival.

23. Thank You!