Factors Associated With Rash in Elderly Patients Receiving Carboplatin Plus Pemetrexed With Dexamethasone Prophylaxis.

BACKGROUND/AIM: Rash is a frequently observed adverse event during therapy with carboplatin (CBDCA) plus pemetrexed (PEM) and may be attributable to PEM. Dexamethasone (4 mg twice daily for 3 days) attenuates PEM-induced rash and is also recommended for managing nausea and vomiting. As the incidence of thoracic cancer is markedly higher in elderly individuals, this study aimed to identify factors for rash development during CBDCA plus PEM treatment under dexamethasone prophylaxis in patients aged ≥65 years. PATIENTS AND METHODS: Patients aged ≥65 years with thoracic cancer receiving CBDCA plus PEM-based treatment with dexamethasone prophylaxis (n=109) were retrospectively assessed. The primary endpoint was factors for the incidence of any-grade rash during the first treatment cycle. Secondary endpoints were factors for any-grade rash during any treatment cycle and change in eosinophils between the baseline and closest evaluation after symptom onset. RESULTS: The incidence of any-grade rash was 18.3% (grade 1: 11.9%, grade 2: 3.7%, grade 3: 2.8%) in the first cycle and 20.2% (12.8%, 4.6%, and 2.8%, respectively) considering all cycles. Most symptoms appeared during the first cycle (90.9%). Multivariable logistic regression analyses identified a history of epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) as a factor preventive against rash development [adjusted odds ratio (95% confidence interval) of 0.18 (0.01-0.94), p=0.04; and 0.17 (0.01-0.94), p=0.04 for the first cycle and any treatment cycle, respectively]. The change in eosinophil level from baseline to the closest evaluation after rash development was not significant. CONCLUSION: Patients with a history of EGFR-TKI treatment are at low risk for rash development during CBDCA plus PEM chemotherapy with dexamethasone prophylaxis in patients aged ≥65 years.