Trends and controversies in the management of carcinoma of the stomach.

The marked decrease in the incidence of carcinoma of the stomach during the past four decades has been worldwide, with a few exceptions. Dietary deficiencies or carcinogenic substances appear to be the most important environmental factor in the genesis of carcinoma of the stomach. The risk of carcinoma of the stomach appears to be determined early in life. Based on the histologic features and the distinct differences in clinical behavior, adenocarcinoma of the stomach can be divided into the intestinal and diffuse types of lesions. In high risk populations, such as the Japanese, the intestinal type is found more frequently, while white Americans tend to have diffuse carcinomas. Premalignant gastric lesions, such as adenomatous polyps, are uncommon causes of carcinoma. The symptoms of carcinoma of the stomach are not specific and there is no satisfactory noninvasive diagnostic test to detect the carcinoma early. In Japan, mass screening, using air contrast radiography and endoscopy of the upper part of the gastrointestinal tract with biopsies and cytologic sampling, leads to detection of early stages of carcinoma of the stomach in 40 per cent of patients. The postsurgical survival rate of these patients is significantly higher, compared with those who have advanced disease. Mass screening for carcinoma of the stomach would not be cost effective in North America. The only curative treatment for carcinoma of the stomach is resection, which is most successful in early stages of carcinomas of the stomach. Radical subtotal gastrectomy is the operation of choice for curative treatment of carcinomas of the body and antrum of the stomach. In Japan, a more extensive lymphadenectomy has improved the five year survival rate. Operations for carcinoma of the cardia are invariably palliative. Palliative resection of an incurable carcinoma of the stomach has been shown to be more worthwhile than a bypass procedure. Adjuvant chemotherapy seems to have improved the unsatisfactory results of radical resection in the treatment of locally advanced carcinoma in Japan, a finding that has not been confirmed in the United States or Europe. The use of intraoperative electron beam radiation to improve the surgical outcome of carcinoma of the stomach is being investigated.