Development of a new equation to estimate creatinine clearance in cancer patients

Can body composition be used to optimize the dose of platinum chemotherapy in lung cancer? A feasibility study

PURPOSE

Current methods of dosing platinum-based chemotherapy are suboptimal. Potentially, taking lean body mass into account may help. To inform the design of a future study, we first examined the feasibility and acceptability of such an approach using dual-energy X-ray absorptiometry (DEXA) and explored aspects suggestive of over- and under-dosing.

METHODS

Patients with lung cancer offered platinum-based chemotherapy over 1 year were identified and, if eligible, invited to take part in a prospective feasibility study. Questionnaires examined acceptability of the DEXA scan and of a future study that randomized between traditional dosing and one adjusted according to body composition. Dose-limiting toxicity (DLT) and a lack of neutropenia explored potential over- and under-dosing, respectively.

RESULTS

Of the 173 patients offered chemotherapy, 123 (71%) were ineligible, mostly because of failing entry criteria (84, 49%). Of the 50 approached, 18 (36%) participated, most receiving carboplatin, with 17 providing data. All found a DEXA scan acceptable; other assessments were fully completed, except nadir and pre-chemotherapy blood counts. Most (94%) were prepared to take part in a future study, although the additional hospital visits for a nadir blood count were unpopular with some. Five (29%) patients experienced six episodes of DLT which resulted in discontinuation (3), dose reduction (2) or change to a less toxic regimen (1). Nine (60%) patients experienced either no (2) or inconsistent (7) neutropenia.

CONCLUSIONS

A randomized trial appears acceptable and feasible in patients receiving carboplatin. Adjustment of our entry criteria and avoiding a hospital visit for a nadir blood count should aid recruitment.

Impact of Body Weight and Body Composition on Ovarian Cancer Prognosis

Measures of body weight and anthropometrics such as body mass index (BMI) are commonly used to assess nutritional status in clinical conditions including cancer. Extensive research has evaluated associations between body weight and prognosis in ovarian cancer patients, yet little is known about the potential impact of body composition (fat mass (FM) and fat-free mass (FFM)) in these patients. Thus, the purpose of this publication was to review the literature (using PubMed and EMBASE) evaluating the impact of body weight and particularly body composition on surgical complications, morbidity, chemotherapy dosing and toxicity (as predictors of prognosis), and survival in ovarian cancer patients. Body weight is rarely associated with intra-operative complications, but obesity predicts higher rates of venous thromboembolism and wound complications post-operatively in ovarian cancer patients. Low levels of FM and FFM are superior predictors of length of hospital stay compared to measures of body weight alone, but the role of body composition on other surgical morbidities is unknown. Obesity complicates chemotherapy dosing due to altered pharmacokinetics, imprecise dosing strategies, and wide variability in FM and FFM. Measurement of body composition has the potential to reduce toxicity if the results are incorporated into chemotherapy dosing calculations. Some findings suggest that excess body weight adversely affects survival, while others find no such association. Limited studies indicate that FM is a better predictor of survival than body weight in ovarian cancer patients, but the direction of this relationship has not been determined. In conclusion, body composition as an indicator of nutritional status is a better prognostic tool than body weight or BMI alone in ovarian cancer patients.