Key Points
ÎReductions from an actual weight-based chemotherapy dose and/or reducing dose intensity may compromise disease-free and overall survival in the curative setting.
ÎConcerns about overdosing an adult obese patient with cancer and no comorbidities based on the use of actual body weight are unfounded.
ÎPractice pattern studies demonstrate that up to 40% of obese patients receive limited doses that are not based on actual body weight.
ÎMany oncologists continue to use either ideal body weight or adjusted ideal body weight or "cap" the body surface area (BSA) at, for example, 2.0 m2 rather than use actual body weight to calculate BSA.
ÎMany overweight and obese patients continue to receive limited chemotherapy doses.
ÎMyelosuppression is the same or less pronounced among the obese than the non-obese who are given full weight-based doses.
ÎPhysicians should respond to all treatment-related toxicities in obese patients in the same ways they do for non-obese patients.
ÎRecent pharmacokinetic studies have clearly demonstrated that actual rather than ideal body weight should be used in dose calculations for chemotherapeutic agents in patients with cancer who are obese.
Advice for Overweight or Obese Patients and Caregivers
ÎPhysicians will prescribe the right amount of chemotherapy based on a patient's actual weight and considering comorbidities. If obese patients or caregivers inquire about dosing, a discussion about the evidence supporting weight-based dosing is appropriate.
ÎPhysicians may have to explain to overweight or obese patients and caregivers that higher doses of chemotherapy are needed to be effective.
ÎSuboptimal treatment could result if chemotherapy dosing is not weight-based.
ÎIt is important to reassure obese patients that toxicity from the appropriate dose of chemotherapy is not expected to be greater.
ÎAdverse effects will be monitored closely. ÎPatients should be warned that costs may be higher.
