Treatment of chemotherapy-induced emesis in the 1990s: impact of the 5-HT3 receptor antagonists.

Considerable progress has been made in the development of means to limit nausea and vomiting arising from cancer chemotherapy. A number of key conceptual advances in the last decade have been critically important. these include recognition of the value of combination antiemetic therapy, identification of important patient- and treatment-related factors predictive of emesis, and appreciation of the importance of serotonin (5-HT) in the pathophysiology of emesis and the value of selective antagonists of the type-3 serotonin receptor. Comparative trials of the 5-HT3 receptor antagonists and classic antiemetic agents have helped define optimal antiemetic approaches in a number of settings. A combination of a 5-HT3 antagonist and dexamethasone is the treatment of choice for patients receiving single- and multiple-day cisplatin. The 5-HT3 antagonists are also effective agents with noncisplatin chemotherapy. Clear-cut superiority to classic antiemetics such as dexamethasone has not been consistently demonstrated, however. Results with the 5-HT3 antagonists in cisplatin-induced delayed emesis have been disappointing to date. The results of ongoing prospective trials should define their role more clearly. At present a combination of metoclopramide and dexamethasone is the treatment of choice in this setting. Results of trials comparing 5-HT3 antagonists are beginning to emerge. Available information suggests no clinically relevant differences in antiemetic efficacy between these agents. Many questions regarding the optimal use of the 5-HT3 antagonists and their integration into clinical practice remain unanswered and are the appropriate focus for additional study.