Weight Loss in Public Hospital Breast Cancer Patients

Institution: LA Biomedical Research Institute at Harbor-UCLA Medical Center
Investigator(s): Rowan Chlebowski, M.D., Ph.D. -
Award Cycle: 2002 (Cycle VIII) Grant #: 8IB-0071 Award: $140,541
Award Type: IDEA
Research Priorities
Community Impact of Breast Cancer>Sociocultural, Behavioral, and Psychological Issues: the human side
Community Impact of Breast Cancer>Disparities: eliminating the unequal burden of breast cancer

Initial Award Abstract (2002)
Women who are obese or who gain weight after a breast cancer diagnosis are much more likely to have a recurrence of disease or die, compared to lighter women. Obesity results in increases in hormones (like insulin and estrogen), which can stimulate breast cancer growth. Obesity is an even greater problem in ethnic/racial minority women commonly seen in public hospital settings. As obesity is becoming much more common in the U.S., this issue will represent an increasing problem in the future.

Our hypothesis is that weight loss in overweight breast cancer patients will favorably change hormone levels and reduce their risk of breast cancer recurrence. In addition, weight loss should increase their quality of life. We propose a feasibility study to demonstrate that weight loss can be achieved by racially and ethnically diverse breast cancer patients seen in public hospitals and that a reduction in fasting insulin levels will result.

We will randomize overweight breast cancer patients seen at our public hospital to either a weight loss program or a control condition. The weight loss program will include dietary instruction, an exercise program, behavioral intervention, and ongoing medical supervision. This strategy is endorsed by National Health agencies as being effective in achieving weight loss. At the end, we will measure weight and hormones to see if weight loss, favorable change in hormones, and improvement in fatigue and quality of life has occurred.

While obesity is strongly related to a bad outlook for breast cancer patients, no prior studies have shown that weight loss and improvement in hormones can be achieved in obese women with early stage breast cancer. We believe that our proposed therapeutic lifestyle intervention can be successful in a public hospital population and will generate the information needed to provide support for a much larger future trial, which will test whether breast cancer patient survival is improved by weight loss.

Final Report (2006)
This study was designed to test the effects of a low calorie diet and a moderate intensity exercise program compared to a control condition on body weight and insulin resistance in overweight postmenopausal women with early stage breast cancer seen in a public hospital setting. Although considerable effect was expended, as described below, to meet the study objectives and recruit the target population, the required intensity of the intervention proved an insurmountable barrier to successfully recruit and retain women with breast cancer seen in this public hospital setting.

Our initial efforts to recruit breast cancer patients began in the medical oncology clinic. Screening activities indicated perhaps one third of the stage eligible patients met other entry criteria. Based on the initial problems in recruitment we expanded our efforts to include the surgical oncology clinic feeling that support of the primary surgeon would aid recruitment. This effort and a change in entry criteria to allow women up to ten years from diagnosis to be eligible for entry resulted in a modest improvement. Next, to further enhance the recruitment pool we had a series of four face to face meetings with investigators at the nearby Martin Luther King / Charles R. Drew General Clinical Research Center to gain their approval to implement the program at their General Clinical Research Center facility. However, various organizational issues beyond our control meant that despite our considerable efforts the inclusion of the King Drew Medical Center could not go forward.

Over the study course, 48 breast cancer patients meeting eligibility requirements were identified and 16 of these were consented to the protocol. Nine completed the visits required to enter the study and were randomized, four to the control condition and five to the intervention. The date of the first randomization was 10/27/03. Of the five intervention women none were able to successfully complete the full 16 session intervention. After this experience, participants on the intervention group described the required 16 sessions as being to difficult to manage given transportation issues and other life priorities.

The personnel time involved in the development of the protocol and intervention materials, submission for human subjects approval, development of revisions in the protocol designed to enhance recruitment and the efforts to involve other institutions in this project required more then the supported personnel time.

Despite this lack of recruitment, our efforts on this project have ongoing value to the state of California and the scientific community. During this period, as the Principal Investigator of the Women's Intervention Nutrition Study (WINS), I reported the results of a 39 institution randomized perspective trial at a plenary session of the major cancer meeting of the American Society of Clinical Oncology in June of 2005 (Chlebowski 2005). In that trial a lifestyle intervention targeting dietary fat intake (but not weight loss) results in a 24% reduction in breast cancer recurrence in women on the intervention group. For women with estrogen receptor negative cancers, the reduction in recurrence risk was 42% (Chlebowski 2005).

In 2006 I was a co-author of the Women's Health Initiative (WHI) report describing the effects of a lifestyle intervention targeting dietary fat intake reduction and increase in fruits and vegetable intake in over 48,000 otherwise healthy postmenopausal women. In that trial there were nine percent fewer new breast cancers seen in the intervention group (P=0.07) and the reduction was statistically significant in women with the highest dietary fat intake at baseline (Prentice 2006).

These two multi-center trials were successfully completed but required enormous resources to achieve recruitment and retention to these interventions requiring multiple personnel contacts to implement. For example, the Women's Health Initiative trial had an estimated total cost of $415 million dollars. Therefore, a more cost-effective approach was needed. In recognition in the effort and resources required to achieve these changes and based on our negative experience with recruitment of women in a public hospital setting it was decided that a less intensive approach in terms of requirement for face to face visits and travel would be needed if a lifestyle intervention targeting breast cancer could have implications for public health particularly in women with modest economic means.

These concepts have lead to the development of a centralized intervention strategy to be performed largely by telephone contact from central interveners. This strategy is in the final stages of development and will go forward with support from the National Cancer Institute of Canada as a full scale outcome study where women with early stage breast cancer will receive not only a dietary fat intake reduction program but reduced caloric intake and increased physical activity targets as well. This full scale outcome study will attempt to implement the intervention we described in the Weight Loss in Public Hospital breast cancer patient study but in a fashion where feasibility without high cost and with a lessened barrier for women of modest economic means will be possible. Thus, our efforts and experience in the Weight Loss in Public Hospital Breast Cancer patient study supported by the University of California will have a direct legacy in this full scale outcome study.

Aromatase inhibitors, tamoxifen, and endometrial cancer in breast cancer survivors