Body mass index as a risk factor for toxicities in patients with advanced soft-tissue sarcoma treated with trabectedin

Objectives: Low body mass index (BMI) and/or low lean body mass have been shown to be risk factors for chemotherapy-related toxicities in a number of different cancers. However, no data are available regarding the role of BMI as a risk factor for developing toxicities related to the novel anticancer agent, trabectedin, in patients with soft-tissue sarcoma (STS). We evaluated the role of BMI as a risk factor for trabectedin-related toxicity in patients with STS. Methods: Data from 51 patients with metastatic/advanced STS treated with trabectedin after progression on ≥1 anthracycline ± ifosfamide regimen were retrospectively reviewed. Results: Eighteen patients (35.3%) were underweight, and the remainder were of normal bodyweight (45.1%) or overweight (19.6%). Neutropenia of any grade (77.8 vs. 33.3%) and grade 3-4 neutropenia (50.0 vs. 18.2%) occurred more frequently in the underweight versus normal/overweight patients (p = 0.025). Febrile neutropenia also occurred more frequently in underweight patients. Differences remained statistically significant after adjusting for other predictors of toxicity. There were no significant differences in other hematological and nonhematological toxicities between the groups. Conclusions: The data suggest for the first time that BMI should be considered a risk factor for neutropenia in patients with STS treated with trabectedin.