Toxicity and effectiveness of carboplatin in obese or overweight patients

To evaluate the efficiency and toxicity of carboplatin using actual body weight in obese/overweight patients using the Calvert formula with Cockcroft-Gault for CrCl estimation.

We evaluated the association of BMI in regards to efficiency and toxicity in a retrospective cohort study of patients who started treatment with carboplatin between 2012 and 2013. Cohorts included obese/overweight patients and normal-weight patients. Efficiency was measured by overall survival, progression-free survival and response rate. Toxicity was measured by the proportion of dose reductions and delays of chemotherapy cycles. We utilized a bivariate and multivariate analysis.

Eighty-six patients were included in the study (50% obese/overweight). There was not a statistically significant difference in effectiveness and toxicity between the two groups in BMI. In the multivariate analysis, BMI not was associated with overall survival (hazard ratio: 0.95, 95% CI: 0.54-1.66, p = 0.849), progression-free survival (hazard ratio: 0.91; 95% CI: 0.54-1.54; p = 0.732), cycle delays (odds ratio (OR): 1.47, 95% CI: 0.80-2.69, p = 0.218) or carboplatin dose reductions (OR: 0.87, 95% CI: 0.35-2.15, p = 0.760). Response rate was 53.5% in both groups.

In our study, obese and overweight cancer patients did not show a statistically significant difference in terms of effectiveness and toxicity compared to normal-weight cancer patients who were treated with carboplatin using their actual body weight with the Calvert formula and Cockcroft-Gault for CrCl estimation. Therefore, it was appropriate to use the actual body weight for our patients.