Changes in weight, body composition, and factors influencing energy balance among premenopausal breast cancer patients receiving adjuvant chemotherapy

Purpose: Weight gain is a common problem among breast cancer patients who r eceive adjuvant chemotherapy (CT). We undertook a study to determine the ca uses of this energy imbalance. Patients and Methods: Factors related to energy balance were assessed at ba seline (within 3 weeks of diagnosis) and throughout 1 year postdiagnosis am ong 53 premenopausal women with operable breast carcinoma, Thirty-six patie nts received CT and 17 received only localized treatment (LT). Measures inc luded body composition (dual energy x-ray absorptiometry), resting energy e xpenditure (REE; indirect calorimetry), dietary intake (2-day dietary recal ls and food frequency questionnaires) and physical activity (physical activ ity records). Results: Mean weight gain in the LT patients was 1.0 kg versus 2.1 kg in th e CT group (P = .02), No significant differences between groups in trend ov er time were observed for REE and energy intake; however, a significant dif ference was noted for physical activity (P = .01). Several differences betw een groups in 1-year change scores were detected. The mean change (+/- SE) in LT versus CT groups and P values for uncontrolled/ controlled (age, race , radiation therapy, baseline body mass index, and end point under consider ation) analysis are as follows: percentage of body fat (-0.1 +/- 0.4 v +2.2 +/- 0.6%; P = .001/0.04); fat mass (+0.1 +/- 9.3 v +2.3 +/- 0.7 kg; P = .0 02/0.04); lean body mass (+0.8 +/- 0.2 v +/- 0.4 +/- 0.3 kg; P = .02/0.30); and leg lean mass (+/- 0.5 +/- 0.1 v -0.2 +/- 0. 1 kg; P = .01/0.11). Conclusion: These data do not support overeating as a cause of weight gain among breast cancer patients who receive CT. The data suggest, however, tha t CT-induced weigh, gain is distinctive and indicative of sarcopenic obesit y (weight gain in the presence of lean tissue loss or absence of lean tissu e gain). The development of sarcopenic obesity with evidence of reduced phy sical activity supports the need for interventions focused on exercise, esp ecially resistance training in the lower body, to prevent weight gain. J Cl in Oncol 19:2381-2389. (C) 2001 by American Society of Clinical Oncology.