POTENTIALLY RESECTABLE GASTRIC-CARCINOMA - CURRENT APPROACHES TO STAGING AND PREOPERATIVE THERAPY

The incidence of gastric carcinoma has declined worldwide during the past several decades, and yet this cancer remains the most common malignancy in several countries around the world, particularly Japan, Chile, and Costa Rica. Gastric carcinoma, although not as common in the United States as it was in the past, is still the eighth most frequent cause of cancer death. For patients with localized gastric carcinoma, surgery remains the most effective therapy, resulting in a consistent but low rate of cure. Unresectable gastric carcinoma is an incurable disease with the exception of a small fraction of patients who are salvaged with chemoradiotherapy. In Western countries curative resection rates have been dismal because of the lack of early diagnosis. Additionally, postoperative adjuvant strategies in the United States and Europe have been ineffective. Even patients with curative resection frequently develop intraperitoneal and systemic carcinoma in addition to locoregional relapses. Many investigators have therefore embarked on the therapeutic strategies of preoperative chemotherapy and postoperative intraperitoneal chemotherapy. The preoperative chemotherapy strategy has particular appeal because of its potential to reduce the size of the primary tumor, thereby allowing a higher rate of curative resection; early systemic therapy of micrometastates might prove biologically more effective. To date, several studies using preoperative chemotherapy have demonstrated its feasibility. The effectiveness of repeated courses of postoperative intraperitoneal chemotherapy remains unsettled mainly owing to the inadequacy of peritoneal drug distribution and the associated toxic effects. Additional investigations are necessary to improve preoperative staging with the use of endoscopic ultrasonography and laparoscopy (peritoneal staging). More effective preoperative chemotherapy combinations that might lead to 5% to 10% complete pathologic response in the presence of modest toxicity must be established prior to launching large-scale trials. The impact of these novel strategies on resection rates, failure sites, and patients' survival can be determined only by carefully designed, controlled clinical trials.