Review Question

Should postsurgical chemotherapy be used routinely in resectable gastric cancer?

Type of Review

This is a Cochrane systematic review of 34 randomized controlled trials (RCTs) comparing surgery and postsurgical chemotherapy to surgery alone for the treatment of stomach cancer.

Relevance for Nursing

Its high incidence and mortality rates make gastric cancer one of the most important cancers of the digestive tract. Surgical resection, the primary treatment for this malignancy, is the sole curative option today. Complete tumor resection is the target of treatment, and every surgical resection typically includes some degree of lymphadenectomy. Once an adequate surgical procedure and lymphadenectomy have been performed, postsurgical chemotherapy is usually the next step. But although chemotherapy seems to improve survival results, it is not a complication-free therapy and several clinical trials have questioned its role. Thus there is a need to evaluate the effectiveness of postsurgical chemotherapy to determine whether it promotes overall and disease-free survival in people with resectable gastric cancer.

Characteristics of the Evidence

This review contained 34 RCTs involving 7,824 patients. Participants were eligible if they were undergoing partial or total gastrectomy for gastric cancer irrespective of the location of the cancer (distal, proximal, or esophagogastric junction). The mean age of patients in the trials was 54 to 65 years and the mean proportion of women was between 19% and 47%. There was no difference in the characteristics of patients in any of the intervention or control groups. Treatment was postsurgical chemotherapy (irrespective of treatment duration and whether a single drug or a combination of drugs was used) versus surgery alone (irrespective of whether pancreatosplenectomy was performed or the presence of microscopic involvement of the resection margins).

There was marked variation between the interventions across trials, and included differences in drugs, doses, and duration of treatment, as well as in study design. The majority of trials based their intervention on 5-fluorouracil or platinum-based chemotherapy, considered for separate analysis by subgroup. The primary outcomes were overall survival and disease-free survival. Most of the trials had a high risk of bias, and in many, allocation was unclear. Blinding was also not performed in the majority of trials. Meta-analysis was undertaken where possible.

Thirty-four trials (7,523 participants) provided data on overall survival with homogenous results. Postsurgical chemotherapy had a significantly beneficial effect on overall survival. Fifteen of these trials (4,133 participants) also reported on disease-free survival; postsurgical chemotherapy showed a beneficial effect here as well.

The group that received chemotherapy had a survival benefit and an improvement in disease-free survival of 15% and 21%, respectively, although all the trials had a high risk of bias. There was no significant difference due to the stage of disease or the chemotherapy agent used.

Best Practice Recommendations

There is evidence to support the use of postsurgical chemotherapy where possible in patients with resectable gastric cancer.

Research Recommendations

Further trials at low risk of bias are needed to determine if postsurgical chemotherapy should be used routinely in every stage of gastric cancer. Additional clarification is required on the chemotherapy agent, standard treatment regimen, and duration of treatment. Quality of life and cost-effectiveness would also benefit consideration.

Source Document