Single Dose of Trastuzumab Kick Starts Immune Response in Certain Breast Cancers

“A tumor’s immune response to a single dose of the HER2 inhibitor trastuzumab predicted which patients with HER2-positive breast cancer would respond to the drug on a more long-term basis, according to the results of a study published recently in Clinical Cancer Research.

“In addition, Vinay Varadan, PhD, assistant professor at Case Western Reserve University School of Medicine and member of the Case Comprehensive Cancer Center, and his colleagues found that women with the HER2-enriched subtype of HER2-positive breast cancer—a subtype that is estrogen and progesterone receptor negative—had the highest rate of immune response to treatment with trastuzumab, with significant increases in immune response after a single dose of the drug.

“ ‘Our study showed, for the first time, that the immune-cell–activating properties of trastuzumab are likely related to the subtypes of breast cancer,’ Varadan said. ‘Knowing this can inform future trials studying the usefulness of adding immunotherapy drugs to trastuzumab.’ “

Higher Folate Intake Associated With Reduced Risk of Hormone Receptor–Negative Breast Cancer in Premenopausal Women

The gist: New research shows that premenopausal women who have more folate in their diet may be less likely to develop estrogen receptor (ER)–negative and progesterone receptor (PR)–negative breast cancer. This doesn’t necessarily mean that folate supplements can prevent cancer. It just shows a correlation between folate and cancer risk.

“In an analysis from the European Prospective Investigation Into Cancer and Nutrition (EPIC) reported in the Journal of the National Cancer Institute, de Batlle and colleagues found reduced risks of estrogen receptor–negative and progesterone receptor–negative breast cancer for highest vs lowest dietary folate intake among premenopausal women.

“The study involved EPIC data from 367,993 women aged 35 to 70 years in 10 European countries. During median follow-up of 11.5 years, 11,575 women developed breast cancer. Folate intake was estimated from country-specific questionnaires…

“The investigators concluded: ‘Higher dietary folate intake may be associated with a lower risk of sex hormone receptor–negative breast cancer in premenopausal women.’ ”

Hormone-Unrelated Breast Cancer Death Rate Lowered by Reducing Dietary Fat

“Reducing dietary fat intake for at least 5 years after diagnosis could help improve survival rates for early-stage breast cancer patients with hormone-unrelated breast cancer, according to a new study.

“The findings of the study were presented at the 2014 San Antonio Breast Cancer Symposium – a 5-day conference aiming to provide state-of-the-art information on breast cancer research to an audience of researchers and physicians from over 90 countries.

” ‘The current findings with respect to long-term influence of dietary lifestyle intervention on overall survival are mixed, but of potential importance,’ reports Dr. Rowan Chlebowski, a medical oncologist from the Harbor-UCLA Medical Center in Torrance, CA.

“The study utilized data taken from the Women’s Intervention Nutrition Study (WINS), a randomized trial that had previously been used to test whether dietary intervention can improve the clinical outcome of women with breast cancer, and assessed death rates after 15 years of follow-up.”

Study Strengthens Evidence that Breastfeeding Can Help Prevent Aggressive Breast Cancer in African-Americans

“A large collaborative study provides new evidence that African-American women may be able to significantly reduce their risk of developing aggressive forms of breast cancer by breastfeeding. The study, published online ahead of print in the Journal of the National Cancer Institute, is based on a collaborative research effort led by researchers at Roswell Park Cancer Institute (RPCI), Boston University’s Slone Epidemiology Center and the University of North Carolina Lineberger Cancer Center.

“African-American women have a disproportionately high incidence of two aggressive forms of the disease: estrogen-receptor-negative (ER-negative) and triple-negative breast cancer, in which tumor cells test negative for three key hormone receptors. Earlier studies have shown a connection between the number of times a woman has given birth, or parity, and increased risk of ER-negative tumors, and that breastfeeding reduced risk of these aggressive breast cancers, but this large new study provides the most conclusive evidence to date of these connections.

“Researchers from the three institutions formed the AMBER Consortium, or African American Breast Cancer Epidemiology and Risk Consortium, by combining four epidemiologic studies with large numbers of African-American participants: the Black Women’s Health Study (BWHS), Multiethnic Cohort Study (MEC), Carolina Breast Cancer Study (CBCS) and Women’s Circle of Health Study (WCHS).”

Lactation Linked to Reduced Estrogen Receptor-Negative, Triple-Negative Breast Cancer Risk

“Women who have had children (parous women) appear to have an increased risk of developing estrogen receptor-negative breast cancer, the subtype that carries a higher mortality rate and is more common in women of African ancestry. A similar relationship was found for triple-negative breast cancer. However, the association between childbearing and increased risk of estrogen receptor-negative and triple-negative breast cancer was largely confined to the women who had never breastfed. These findings, published in the Journal of the National Cancer Institute, suggest that low rates of breastfeeding in African American women may contribute to their higher incidence of the more aggressive and difficult-to-treat subtypes of breast cancer.

“Researchers from Boston University’s Slone Epidemiology Center (SEC) collaborated with the Roswell Park Cancer Institute of Buffalo, NY and the University of North Carolina Lineberger Cancer Center to form a consortium to study the determinants of breast cancer subtypes in African American women. They combined data on breast cancer cases and controls from four large studies, including the Boston University Black Women’s Health Study. The combined analyses included 3,698 African American women with breast cancer, including 1,252 with the estrogen receptor-negative subtype.

“They found that parous women had a 33 percent higher chance of developing estrogen receptor negative breast cancer than women who had never given birth. Women who had four or more births and had never breastfed any of their babies had a 68 percent higher chance of developing this type of cancer compared with women who had only one birth and had breastfed that baby. By contrast, parous women who had four or more births had a slightly decreased risk of estrogen receptor-positive breast cancer, regardless of whether or not they had breastfed.”

BRCA Mutation Incidence Comparable Between ER-Negative, ER-Low–Positive Breast Tumors

The gist: Researchers say that breast cancer patients younger than 60 who have ER-low-positive tumors should be “referred for genetic counseling and BRCA testing.” This is because a BRCA1 or BRCA2 mutation may affect treatment choices.

“The rate of deleterious BRCA1 or BRCA2 germline mutations detected in patients with ER-low–positive breast cancer is similar to that observed in patients with ER-negative breast cancer, according to study results presented at the Breast Cancer Symposium.

“The findings suggest the potential for underutilization of BRCA testing among appropriate patients, researchers wrote.

“ ‘In light of the life-saving interventions that may be offered to a patient once he or she has been identified to carry a deleterious BRCA mutation, we strongly recommend patients younger than age 60 with ER-low–positive tumors be referred for genetic counseling and consideration of BRCA testing,’ Rachel A. Sanford, MD, a fellow in cancer medicine at The University of Texas MD Anderson Cancer Center, said during a presentation.”