Breast Cancer: Carboplatin Yields Fabulous Results for Triple Negative Type

cancer management

The results of several studies reported at the 2013 San Antonio (USA) Breast Cancer Symposium are potentially practice-changing. Let’s look at one of those reports: Carboplatin as a neoadjuvant therapy for triple negative (estrogen receptor negative, progesterone receptor negative, HER2 overexpression negative) breast cancer. Those with this subtype of breast cancer received a regimen that included the chemotherapy drug carboplatin. The odds of a pathologic complete response (disappearance of all signs of cancer (under the microscope) in the breast were 60% (compared to 46% for those not receiving this drug as a part of chemotherapy).

My Take: The role of the so-called platinum drug carboplatin as chemotherapy for “triple negative” breast cancer has been debated for many years. We finally have a randomized trial showing that carboplatin clearly increases the pathologic complete response. I think that this study will likely change how patients with this breast cancer subtype are managed, at least when chemotherapy is given before surgery. Still, we do not have long-term data to prove that this improved pathologic complete response rate translates into higher relapse-free numbers, or improved survival. Great study, and good news for those with this particularly risky type of breast cancer. I’m Dr. Michael Hunter.

The small print: The material presented herein is informational only, and is not designed to provide specific guidance for an individual. Please check with a valued health care provider with any questions or concerns. As for me, I am a Harvard- , Yale- and UPenn-educated radiation oncologist, and I practice in the Seattle, WA (USA) area. I feel genuinely privileged to be able to share with you. If you enjoyed today’s offering, please consider clicking the follow button at the bottom of this page.

Available now: Understand Colon Cancer in 60 Minutes; Understand Brain Glioma in 60 Minutes. Both can be found at the Apple Ibooks store. Coming Soon for iPad:  Understand Breast Cancer in 60 Minutes; Understand Colon Cancer in 60 Minute; Understand Colon Cancer in 60 Minutes; Understand Brain Glioma in 60 Minutes. Thank you.

Reference: Sikov WM, et al. Impact of the addition of carboplatin and/or bevacizumab to neoadjuvant weekly paclitaxel followed by dose-dense AC on pathologic complete response rates in triple-negative breast cancer: CALGB 40603. Abstract S5-01. Presented December 13, 2013.

Body Fat Distribution and ER-negative Breast Cancer

What scientists call "Overweight" ch...
Photo credit: Wikipedia

Body fat distribution does not play an important role in the incidence of every subtype of premenopausal breast cancer, but is associated with an increased risk for estrogen receptor (ER)-negative breast cancer, according to a study published December 15 in The Journal of the National Cancer Institute. abdominal adiposity, or waist circumference and the waist to hip ratio, was more strongly associated with risk of ER-negative breast cancer than with the risk of ER-positive breast cancer. The researchers found no statistically significant associations between waist circumference, hip circumference, or the waist to hip ratio and overall risk of breast cancer.

“These findings may suggest that an insulin-related pathway of abdominal adiposity is involved in the etiology of premenopausal breast cancer,” the authors write.

Study Details: Previous studies have shown that the association between body mass index (BMI) and the risk of breast cancer varies with menopausal status: a higher BMI is positively associated with risk of postmenopausal breast cancer but inversely associated with risk of premenopausal breast cancer. Intra-abdominal fat that surrounds organs has been associated with metabolic and hormonal changes that have been associated with premenopausal breast cancer risk, although prospective studies have produced conflicting results, and none have examined the role of hormone receptor status.

To determine the relation between body fat distribution and premenopausal breast cancer risk, Holly R. Harris, Sc.D., of Brigham and Women’s Hospital and Harvard Medical School in Boston, and colleagues, conducted a prospective analysis among women in the Nurses’ Health Study II, a cohort of 116,430 women who have been followed up since 1989. In 1993 the researchers sent women in that study a questionnaire in which the women were asked to measure and report their waist and hip circumference.

I’m Dr. Michael Hunter.

The small print: The material presented herein is informational only, and is not designed to provide specific guidance for an individual. Please check with a valued health care provider with any questions or concerns. As for me, I am a Harvard- , Yale- and UPenn-educated radiation oncologist, and I practice in the Seattle, WA (USA) area. I feel genuinely privileged to be able to share with you. If you enjoyed today’s offering, please consider clicking the follow button at the bottom of this page.

Available now: Understand Colon Cancer in 60 Minutes; Understand Brain Glioma in 60 Minutes. Both can be found at the Apple Ibooks store. Coming Soon for iPad:  Understand Breast Cancer in 60 Minutes; Understand Colon Cancer in 60 Minute; Understand Colon Cancer in 60 Minutes; Understand Brain Glioma in 60 Minutes. Thank you.

Reference: Journal of the National Cancer Institute (2010, December 15). Body fat distribution associated with a higher risk of ER-negative breast cancer. ScienceDaily. Retrieved November 28, 2013, from http://www.sciencedaily.com­/releases/2010/12/101215163742.htm

Triple-Negative Breast Cancer: Risk Factors

breast cancer in female body diagram

Breast cancer growth may be driven by the so-called female hormones, estrogen and progesterone, or by HER2. But some breast cancers are not driven by any of these; the ER/PR/HER2 negative cancers are sometimes referred to as “triple negative,” and represent among the most aggressive breast cancers. So why do these cancers occur? What are the risk factors for triple negative breast cancer?

Two of the largest studies to date look at triple-negative breast cancer, and have found some reproductive factors (pregnancy and multiple childbirth), obesity, and lack of physical activity to increase risk.

The Research: Both studies used data from more than 155000 women enrolled in the Women’s Health Initiative. Of the group, 307 developed triple-negative breast cancer after a follow-up of 8 years, and 2610 were found to have estrogen-receptor-positive (ER+) breast cancer.  Let’s look at each of these studies:

  1. In the first study, investigators found that obese women had a 35% higher risk (they were 1.35x more likely) for triple-negative breast cancer, as compared to women with the lowest body mass index (BMI).
  2. In the second study, the number of births affected risk for triple negative breast cancer: Women who had given birth to 3 or more children were at higher risk than women who had given birth to one child (hazard ratio 1.46).

My Take: Triple negative breast cancer appears to be a very different disease, compared to the other breast caner subtypes. While the hormonal changes of pregnancy makes the breast less susceptible to ER-positive breasy cancer, these mechanisms do not reduce the risk for triple-negative disease. The link between pregnancy and increased risk for triple-negative breast cancer may be due to an abnormal response of the breast to pregnancy. Obesity and physical inactivity, on the other hand, might increase risk bu affecting insulin-like growth factors or inflammatory changes in the breast. I’m Dr. Michael Hunter.

The small print: The material presented herein is informational only, and is not designed to provide specific guidance for an individual. Please check with a valued health care provider with any questions or concerns. As for me, I am a Harvard- , Yale- and UPenn-educated radiation oncologist, and I practice in the Seattle, WA (USA) area. I feel genuinely privileged to be able to share with you. If you enjoyed today’s offering, please consider clicking the follow button at the bottom of this page.

Available now: Understand Colon Cancer in 60 Minutes; Understand Brain Glioma in 60 Minutes. Both can be found at the Apple Ibooks store. Coming Soon for iPad:  Understand Breast Cancer in 60 Minutes; Understand Colon Cancer in 60 Minute; Understand Colon Cancer in 60 Minutes; Understand Brain Glioma in 60 Minutes. Thank you.

Reference: Cancer Epidemiol Biomarkers Prev. Published online March 1, 2011. Abstract; J Natl Cancer Inst. Published online February 23, 2011. Abstract; Medscape Medical News, 2011 WbeMD LLC.

ER, PR, and HER2: Why Re-check for Metastases?

Background: Estrogen receptor status, progesterone receptor status, and HER 2 status are essential to classifying breast cancer into major subtypes requiring varying treatments: HER2-enriched; hormone receptor positive; and triple negative breast cancers. The status or ER, PR, and HER2 are checked for the primary (original cancer in the breast), but should we re-check the metastasis? Do ER, PR, and HER2 change?

Metastatic breast carcinoma; pleura-Estrogen r...
Metastatic breast carcinoma; pleura-Estrogen receptor (Photo credit: Pulmonary Pathology)

What the researchers did: Receptor statuses wre assed by immunohistochemistry with a cutoof of ER or PR 10% positive. HER2 was considered positive if IHC was 3+ or FISH amplification ratio >2.

Results: Discordance (the status changed) in one or more receptors between primary breast cancer and metastatic disease was found in 42% of patients. A switch in receptor status was found for ER in 17% of tumors, PR in 29% of tumors, and HER2 in 4%. Exposure to anthracycline chemotherapy (e.g. doxorubicin or Adriamycin) was statistically associated with switches in ER status. Discordance for ER was almost statistically significant for metastases to the liver, and PR discordance was statistically significant for liver spread.

My take: This study confirms that discordance in ER and PR expression between the primary breast tumor and the corresponding metastatic lesion is high, whereas HER2 remains relatively constant. These results were obtained in a selected group of patients, so additional studies are needed. Still, it is probably wise to biopsy the first site of metastasis to re-check the receptors. I’m Dr. Michael Hunter.

The small print: The material presented herein is informational only, and is not designed to provide specific guidance for an individual. Please check with a valued health care provider with any questions or concerns. As for me, I am a Harvard- , Yale- and UPenn-educated radiation oncologist, and I practice in the Seattle, WA (USA) area. I feel genuinely privileged to be able to share with you. If you enjoyed today’s offering, please consider clicking the follow button at the bottom of this page.

Available now: Understand Colon Cancer in 60 Minutes; Understand Brain Glioma in 60 Minutes. Both can be found at the Apple Ibooks store. Coming Soon for iPad:  Understand Breast Cancer in 60 Minutes; Understand Colon Cancer in 60 Minuteable now: Understand Colon Cancer in 60 Minutes; Understand Brain Glioma in 60 Minutes. Thank you.

Reference: The Oncologist 2013:18:667-674 (www.TheOncologist.com)