430PEmetic risk of carboplatin plus pemetrexed is higher than that of carboplatin plus paclitaxel in patients with lung cancer: A propensity score-matched analysis

Abstract Background The emetogenic classification of antineoplastic agents has provided a framework for defining antiemetic treatment recommendations in international guidelines. The most widely used classification schema identified four emetic risk levels. However, information on the emetogenicity of each chemotherapeutic regimen is insufficient. We previously reported that the emetic risk of pemetrexed was higher than that of taxans. Risk factors for chemotherapy-induced nausea and vomiting (CINV) were also assessed in patients with lung cancer receiving carboplatin plus pemetrexed (CBDCA+PTX) or carboplatin plus paclitaxel (CBDCA+PEM), and the CINV incidence was compared between these two regimens. Methods Data were pooled from two prospective studies, and propensity score matching was used to compare the CINV incidence between CBDCA+PTX and CBDCA+PEM groups. Risk factors for CINV were identified using logistic regression models. The pattern of CINV occurrence was evaluated by 7-day patient diary for recording CINV after the commencement of chemotherapy. Results Among 240 evaluable patients, the CINV incidence was higher in the CBDCA+PEM group than in the CBDCA+PTX group at the delayed phase (nausea: 51.1% vs. 36.2%, P = 0.040; vomiting: 23.4% vs. 14.9%, P = 0.138). The pattern of delayed CINV occurrence peaked on days 5 and 4 for CBDCA+PEM and CBDCA+PTX regimens, respectively. Logistic regression analysis identified younger age, female sex, no alcohol consumption, two antiemetics, and CBDCA+PEM regimen as independent risk factors associated with delayed nausea, and female sex and two antiemetics for delayed vomiting. Conclusions The emetic risk of CDBCA+PEM regimen was higher than that of CBDCA+PTX regimen. More aggressive antiemetic prophylaxis such as quadruple therapy, including olanzapine, may be considered in patients receiving CDBCA+PEM regimen. Legal entity responsible for the study The authors. Funding Has not received any funding. Disclosure All authors have declared no conflicts of interest.