The place of adjuvant and neoadjuvant chemotherapy in the treatment of gastric cancer

The incidence of gastric adenocarcinoma has decreased dramatically in most Western countries over the past five decades. However, the five-year survival rate remains poor and late diagnosis is one of the main reasons for the lack of marked improvement in outcome. More than 50% of the patients found to have advanced local (stage T III), or systemic (stage T IV) gastric cancer at the time of diagnosis. This review article examines the current state of chemotherapeutic regimens additive to surgery, based on a computer-supported literature search (MED-LINE and CANCERLIT). Since 1980 15 randomized studies have been performed to evaluate the efficacy of systemic adjuvant chemotherapy. Of these, 13 were published in the Western English Literature and 2 were Japanese studies, encompassing a total of over 2000 patients. In 3 studies adjuvant chemotherapy was administered intraperitoneally. An evaluation of these studies failed to demonstrate any advantage for the outcome of chemotherapy on-patients with curative resected gastric carcinoma. Thus, according to present knowledge, this form of adjuvant treatment cannot be recommended for routine clinical management. In order to evaluate the effect of neoadjuvant chemotherapy, 17 randomized studies have been reviewed. In 6 studies (3 Western studies, 3 Japanese studies) neoadjuvant chemotherapy was investigated in patients with potentially curative resectable gastric carcinoma. 11 Western studies reported the results of neoadjuvant chemotherapy in cases of locally advanced disease. It appears that neoadjuvant chemotherapy of locally advanced non-resectable gastric cancer in patients who do not have distant metastases and/or ''carcinosis peritonei'' reduces tumor size in 30-40% of the patients, thus enabling radical resection in a second look operation. The efficacy of neoadjuvant chemotherapy in potentially resectable gastric carcinoma cannot be definitely assessed at the present time since only scant, preliminary findings are available. Future goals for the treatment of gastric carcinoma should include studies evaluating preoperative chemotherapy using effective, but less toxic substances, based on exact tumor-staging by means of endoluminal sonography. Furthermore, research projects investigating the value of intraperitoneal therapeutic regimens such as hyperthermic chemoperfusion or intraperitoneal instillation of the requisite substances in the prevention of intraperitoneal carcinomatosis and local recurrence will be of great importance.