Gastric Carcinoma and Extended Surgery

1. Gastric Carcinoma and Extended Surgery - Dr Steven Dubenec (Mentor: Dr Bryan Yeo)

2. Diffuse M:F 1:1 Onset Middle Age 5 yr surv overall <10% Aetiology Diet H. pylori Intestinal M:F 2:1 Onset Middle Age 5 yr surv overall 20% Aetiology Unknown Blood group A association H. pylori Gastric Carcinoma

3. Gastric Carcinoma • Japanese & Chinese mortality rates for Gastric Ca ~2x southern hemisphere • Disease of lower socioeconomic groups

4. Gastric Carcinoma Staging • JRSGC – PHNS System P- Grade of peritoneal spread H- Presence of Hepatic Mets N- Extent of lymph node involvement S- Extent serosal invasion • Internationally Unified TMN Staging

6. Gastric Carcinoma Surgery • Western societies when resecting stomach tend not to be as extensive as the Japanese • The extent of resection is described as • D1. Limited Lymphadenectomy. All N1 Nodes removed en bloc with the stomach • D2. Systematic Lymphadenectomy. N1 & N2 nodes en bloc with stomach • D3. Extended Lymphadenectomy. A more radical en bloc resection including N3 nodes

8. Gastric Carcinoma Surgery • The case for D2 systematic lymphadenectomy is controversial • Japan practices this routinely • Western medicine tends to take a more conservative approach

9. Indications for Splenectomy • If macroscopic disease can be resected & the operation is potentially curative then en bloc splenectomy or pancreaticosplenectomy is worthwhile. • If it is more palliative then this benefit must be weighed against the potential complications of splenectomy and more extensive operation

10. Distal Pancreatectomy • Associated with marked increase in morbidity & mortality with or without splenectomy • Indications for pancreatectomy: • Direct invasion of the tail of the pancreas • Likelihood of splenic artery nodal involvement

11. “No survival benefit from combined pancreaticosplenectomy and total gastrectomy for gastric cancer” Kitamura K, et al., Br J Surg 86:119-122; 1999

12. Introduction • Gastric Carcinoma is a common fatal malignancy • More common in Japan c/w rest of world • Japan reports better survival rates • Stage Migration • Thinner Population • Experience with Gastric Surgery

13. Introduction • Combined pancreaticosplenectomy does have increased morbidity & mortality† • †Cuschieri A, Fayers P, Fielding, etal. Postoperative morbidity and mortality after D1 & D2 resections for gastric cancer: preliminary results of the MRC randomised controlled surgical trial. The Surgical Cooperative Group. Lancet 1996; 347: 995-9

14. Question? • Does Extended Surgery for Gastric Carcinoma offer any survival benefit?

15. Methods • Retrospective Study • Data collected from 1969 – 1996 • Total number of patients undergoing gastric surgery 1844 • 190 – Total Gastrectomy + Pancreaticosplenectomy • 206 Total Gastrectomy + Splenectomy

16. Methods • Pathology based on Japanese Research Society for Gastric Surgery • Patients with direct invasion of pancreas or suspected lymph nodes along splenic artery had TG+PS • Patients with suspected splenic hilum nodes had TG+S

17. Statistical Analysis • c2 used to assess clinicopathological difference between groups • Kaplan-Meier used for cumulative survival rates • Wilcoxon test used for survival curves

18. Results • No differences in ages or sex between groups • TG+S groups had smaller tumours and were more superficial (p<0.005) • TG+PS groups had more frequent lymph node metastases & were more histologically advanced • No difference in histological type

19. Morbidity

20. Post-Op Survival • (9/190) 5% of TG+PS died within 30/7 of Post-Operatively • (12/206) 6% of TG+S died within 30/7 of Post-Operatively

21. Post-Op Survival • Survival rates only for stage 3&4 disease looked at because of numbers

22. Post-Op Survival • No Statistical Significance Between Survival of Stage 3&4 Disease for TG+S & TG+PS • 5 Year Survival

23. Post-Op Survival

24. Post-Op Survival

25. Pancreaticosplenectomy • 83 patients had TG+PS for direct invasion of pancreas • 104 patients had TG+PS when lymph node metastasis was evident or suspected • 46/83 had histological confirmation of direct invasion • 22/104 had confirmation of lymph node metastasis at histology • 6 of 46 lived for > 5 years • 2 of 22 lived > 5 years

26. Discussion • Assumption that TG+PS has improved survival rate • TG+PS routine in Japan >30 years • No direct evidence

27. Discussion • Of the TG+PS 6 long term survivors with direct invasion of pancreas • 2 patients with metastases along splenic artery survived > 5years after TG+PS • 20 of 22 Patients with splenic hilar nodes died before 5 years after TG+S

28. Discussion • TG+S does not appear to be beneficial in patients with splenic hilar nodes • Extended Surgery offers some advantages for patients with direct invasion of pancreas body or tail • TG+PS has most morbidity

29. Discussion • TG+PS mortality in Japan is about 10% c/w 1996 MRC trail in UK 16% • ? This due to • More surgical experience with this disease • Thinner patients • Case mix differences • Co-morbidities

30. Conclusion • Extended surgery for Gastric Ca not beneficial unless there is direct invasion of the pancreas body or tail • TG+PS not routine • TG+PS not useful for lymph node metastases along splenic artery

31. Pros • Purpose clearly stated • Good comprehensive collation of results which were well presented • Results collated support the conclusions derived • This study offer clinical significance for surgical treatment of Gastric Ca

32. Cons • Retrospective study • Surgical decision for TG+S or TG+PS was subjective ? • Anatomical position of tumour. Is it important? • ? Co-morbidities of the patients. Did they die of causes other than their Ca • No mention of the specific post-op complications that led to patients death within the 30/7