GASTRIC-CANCER IN ASIA - PROGRESS AND CONTROVERSIES IN SURGICAL-MANAGEMENT

Considerable controversy surrounds the management of gastric cancer an d this has largely overshadowed recent progress in our understanding o f the epidemiology and molecular pathogenesis of the disease, and impr ovements in diagnostic and staging techniques. Differences identifiabl e in the molecular pathogenesis of the 'intestinal' and 'diffuse' type s of gastric cancer may help to unravel the biological behaviour of va riants and ultimately influence therapeutic strategies. Endoscopic ult rasound is well established as being accurate for T staging and the in troduction of laparoscopy, with or without ultrasound, is obviating un necessary laparotomy in nonbleeding, non-obstructed patients. Controve rsies in surgery encompass the role of laparoscopic surgery in early g astric cancer, the extent of lymphadenectomy including para-aortic nod al dissection, resection of en bloc contiguous organ involvement, panc reatosplenectomy, left upper abdominal evisceration, and modes of reco nstruction (pylorus-preserving gastrectomy, pouch formation) to enhanc e quality of life. Whereas adjuvant chemotherapy does not impact favou rably on survival, emphasis has now shifted to neoadjuvant (induction) chemotherapy to downstage the disease. Preoperative regional chemothe rapy and intra-operative hyperthermic chemotherapy or irradiation may prove to be of benefit in patients with resectable disease, but some s cepticism still exists as to the usefulness of biological response mod ifiers (e.g. OK432, PSK) for adjuvant treatment. Ethical issues relati ng to cultural differences in Asia sometimes mitigate against adequate trial design (e.g. a surgery-alone control group or a no adjuvant the rapy treatment group may be considered inappropriate) and this has und erstandably hindered acceptance in Western countries of the value of c urrent management practices in Asia. These issues and the need for ong oing well-conducted randomized trials with prospective subset analysis are now being addressed.