Actual body weight for determining doses of chemotherapy in obese cancer patients: evaluation of treatment tolerability.

In our Department, doses of chemotherapy in obese cancer patients are routinely calculated according to actual body weight. As some physicians question this policy, we prospectively evaluated the safety of this approach. Of 606 consecutive patients, 178 (29%) were obese, defined as body mass index > or =27.3 kg/m2 for females and > or =27.8 kg/m2 for males; full-dose chemotherapy was initiated in 147 (24%). Severe chemotherapy- related toxicity (SCRT) (neutropenic fever, severe thrombocytopenia associated with significant bleeding and/or requiring platelet transfusion, or grade 3-4 nonhematologic toxicity other than alopecia, nausea, and vomiting) during the first three cycles was evaluated. SCRT was noted in 16/147 (11%) during the first cycle, 10/146 (7%) during the second cycle, and 6/142 (4%) during the third cycle. Drug doses were reduced due to toxicity in 15/146 (10%) during the second cycle and 11/142 (8%) during the third cycle. There were no treatment- related deaths. It was concluded that calculation of standard chemotherapy dose according to actual body weight in obese patients is relatively safe.