Lexicillin QD

WIN study shows effect of dietary fat on breast cancer

This is from the "Mature analysis from the women’s intervention nutrition study
(WINS) evaluating dietary fat reduction and breast cancer outcome, " Chlebowski, et al. abstract presented at the last San Antonio Breast Cancer Symposium.

This is a randomized, prospective, multi-center study looking at the relationship of dietary fat with breast cancer outcomes. This graph shows the relapse-free survival of women with triple negative disease. It appears to be the most significant result (P=.001), for all the subgroups.

If this were a study testing a new drug, it would certainly be noteworthy.

One confounding factor could be that women who were on the low-fat diet did experience significant weight loss which might be the causal factor in this result. Also, in the next study, it might be useful to look at the type of fat included in the diet as opposed to amount. Mono- and polyunsaturated oils as constituents of fat in the diet should probably be distinguished from saturated fats.

From the SABCS Web site:

[32] Mature analysis from the womens intervention nutrition study (WINS) evaluating dietary fat reduction and breast cancer outcome.

Chlebowski RT, Blackburn GL, Elashoff RM, Hoy KM, Thomson CA, Nixon DW, Giuliano AE, McAndrew P, Hudis C, Butler J, Merkel D, Shapiro A.. LABioMed, Torrance, CA; Beth Israel Deaconess Hospital, Boston, MA; University of California, Los Angeles, CA; Cancer Prevention Institute, New York, NY; University of Arizona, Tucson, AZ; St Johns Hospital and Health Center, Santa Monica, CA; Cedars Sinai Hospital, Beverly Hills, CA; Memorial Sloan-Kettering Cancer Center, New York, NY; University of California at Irvine, City of Orange, CA; Evanston Hospital, Kellogg Cancer Care Center, Evanston, IL; Park Nicollet Institute, Minneapolis, MN

Background: We have previously initiated a randomized clinical trial evaluating the relationship between dietary fat intake and breast cancer outcomes.
Material and Methods: A randomized, prospective, multi-center clinical trial was conducted to test whether dietary intervention designed to reduce fat intake was more effective than a control condition in women with resected early stage breast cancer receiving conventional cancer management. The primary endpoint was relapse-free survival.
Results: A total of 2,437 women were randomized 40:60 to dietary intervention or control groups between 1997 and 2001. Dietary fat intake was lower in the intervention compared to the control group (fat grams/day at 12 months, 33.3 + 17.0 mean + standard deviation (SD) versus 51.3 + 24.4, respectively, P<0.001) corresponding with a significantly lower (P=0.005) mean body weight in the intervention group as well. After a median of 60 months (data through October 2003) an interim efficacy analysis was reported in May, 2005 (Chlebowski et al, Proc Amer Soc Clin Onc 2005;24:10). A total of 277 events (local, regional, distant, or ipsilateral breast cancer recurrence or new contralateral breast cancer) were reported: 96 of 975 in the dietary group and 181 of 1462 in the control group. The hazard ratio in the intervention compared with the control group was 0.76 (95% confidence interval 0.60- 0.98, P=0.077 for stratified log rank and P=0.034 for adjusted Cox model analysis). Exploratory analyses suggested a differential dietary effect based on hormonal receptor status. The dietary intervention was ended in May 2004. Non-intervention follow-up has continued and the database will be closed at the end of September 2006, resulting in an estimated median follow-up of 95 months in surviving patients.
Discussion: A mature analysis of WINS will meet original protocol design plans and provide a more definitive assessment of the relationship between dietary fat intake and breast cancer patient outcome.

Saturday, December 16, 2006 11:15 AM

General Session 5 (9:30 AM-11:30 AM)

Elizabeth Edwards' recurrent breast cancer: estrogen/progesterone positive

This is certainly good news as far as treatment options are concerned. Of the 3 hormonal markers (receptors) breast cancer may express, estrogen, progesterone, and HER2, Elizabeth's recurrence tested positive for the first two.

From a story on CNN:

Mrs. Edwards had her first post-diagnosis doctor's visit Friday and emerged encouraged. She said her doctor expected she had the most aggressive "triple-negative" cancer, but testing found that she had two of the three key hormonal receptors -- estrogen and progesterone. She said her the original diagnosis was "slightly estrogen heavy," but this time it's a strong marker and she also has the second marker.

This means that Edwards is eligible for treatment by an aromatase inhibitor. The CNN story says that she is being treated with letrozole as well as a medication to prevent bone loss, such as a bisphosphonate.

John Edwards' wife has recurrence of breast cancer

From what I've seen so far in the news, Mrs. Edwards was experiencing left-sided rib pain. Radiologic studies show that she may have had a fracture on the left side, but further studies (possibly a PET scan) showed evidence of recurrence in a rib on the right side.

According to the latest recommendations from the National Comprehensive Cancer Network's recently updated Practice Guidelines in Oncology (link to the pdf), for diease that is estrogen receptor/progesterone receptor (ER/PR) positive or bone/soft tissue only or asymptomatic visceral spread, hormonal therapy is indicated. These include the antiestrogens (tamoxifen) or an aromatase inhibitor (exemestane, letrozole or anastrozole). If a prior antiestrogen was given within 1 year, second-line hormonal therapy is indicated. This is assuming the patient is postmenopausal. A premenopausal woman would be considered for ovarian ablation in additional to the hormonal therapy.

In the case of ER/PR status being negative or there is symptomatic visceral or hormone refractory disease, chemotherapy is indicated, and trastuzumab considered depending upon the patient's HER2 positivity.

For chemotherapy, the Guideline lists preferred single agents, and preferred combinations.

As always, I'm hoping for the best outcome for her, and other patients with this disease.