PROPOSAL FOR CLASSIFYING THE ACUTE EMETOGENICITY OF CANCER-CHEMOTHERAPY

Purpose: To propose a classification of the acute emetogenicity of ant ineoplastic chemotherapy agents, and to develop an algorithm to define the emetogenicity of combination chemotherapy regimens. Methods: A Me dline search was conducted to identify (1) clinical trials that used c hemotherapy as single-agent therapy, and (2) major reviews of antiemet ic therapy, The search was limited to patients who received commonly u sed doses of chemotherapy agents, primarily by short(< 3 hours) intrav enous infusions. Based on review of this information and our collectiv e clinical experience, we assigned chemotherapy agents to one of five emetogenic levels by consensus. A preliminary algorithm to determine t he emetogenicity of combination chemotherapy regimens was then designe d by consensus. A final algorithm was developed after we analyzed a da ta base composed of patients treated on the placebo arms of four rando mized antiemetic trials. Results: Chemotherapy agents were divided int o five levels: level 1 (< 10% of patients experience acute [less than or equal to 24 hours after chemotherapy] emesis without antiemetic pro phylaxis); level 2 (10% to 30%); level 3 (30% to 60%); level 4 (60% to 90%); and level 5 (> 90%). For combinations, the emetogenic level was determined by identifying the most emetogenic agent in the combinatio n and then assessing the relative contribution of the other agents. Th e following rules apply: (1) level 1 agents do not contribute to the e metogenic level of a combination; (2) adding greater than or equal to one level 2 agent increases the emetogenicity of the combination by on e level greater than the most emetogenic agent in the combination; and (3) adding level 3 or 4 agents increases the emetogenicity of the com bination by one level per agent. Conclusion: The proposed classificati on schema provides a practical means to determine the emetogenic poten tial of individual chemotherapy agents and combination regimens during the 24 hours after administration. This system can serve as a framewo rk for the development of antiemetic guidelines. (C) 1997 by American Society of Clinical Oncology.