SABCS: Breast Cancer Breakthroughs
A roundup of news from the annual San Antonio Breast Cancer Symposium (SABCS), the premier scientific symposium in the world for breast oncologists, breast cancer researchers, and associated healthcare professionals, held Dec. 5-8.
What do you call nearly 8,000 doctors, researchers, and other medical personnel, from over 100 countries, gathered in San Antonio for 4 days to hear 1200+ presentations centered around breast cancer?
SABCS – the San Antonio Breast Cancer Symposium, whose mission is to “encompass the full spectrum of breast cancer research and facilitate the rapid transition of new knowledge into improved care for breast cancer patients.”
Most of the information coming out of SABCS is highly technical, and represents research that, in time, might produce significant advances in breast cancer treatment. But for the moment, much of the “news” at SABCS, while critically important to researchers, isn’t actionable for the typical breast cancer survivor.
I’ve culled through the various papers and press releases coming out of SABCS, which can be quite daunting. For instance, “Mechanism-based insights into prognosis and treatment of breast cancer derived from high resolution multiphoton imaging” isn’t something that the typical layperson would find instantly engaging.
Many presentations involved new drugs in clinical trials (often obvious PR pieces launched by the drug companies themselves). And many more covered ongoing research that’s interesting (e.g., DNA repair), but years away from becoming useful to the average oncologist and his/her patient.
The following represent topics from the 2012 SABCS that I think you’ll find interesting, and in some cases actionable as well.
HER2+ – a new method of identification
This sub-type of breast cancer, which affects about 20% of women diagnosed, is effectively treated with a combination of chemotherapy and Herceptin, a targeted therapy. Currently, patients are identified as being HER2+ via one of two tests, both of which measure “gene amplification” – the presence of too many of a certain set of genes.
Now it appears that not just gene amplification, but gene mutation may signal the presence of HER2+ breast cancer. Researchers used DNA sequencing to identify women who had HER2+ breast cancer that hadn’t been detected by standard tests. Had these women and their doctors known their cancer was HER2+, they would have received Herceptin, and thus lessened their risk of recurrence.
What will this new information mean to women currently being diagnosed with breast cancer?
Nothing, at the moment; more study is needed before researchers can identify the exact pattern of gene mutations that signal a woman will respond well to Herceptin. But it’s another step in the direction of ultra-personalized treatment – where your individual DNA will be used to identify the cancer treatment that’s best for YOU, rather than what’s best for the average woman with a similar diagnosis.
Extra tamoxifen helps; extra Herceptin doesn’t
Many of us taking long-term hormone drugs or targeted therapies wonder, when the prescribed regimen is up – “Was that enough? Shouldn’t I continue to take this drug that’s supposedly working to keep my cancer at bay?”
For those of you taking tamoxifen, a new study shows that taking it for 10 years, rather than the currently accepted protocol of 5 years, does indeed lower your risk of recurrence, and improve your chance of long-term survival. Women who took the extra 5 years of tamoxifen had a 25% lower rate of recurrence, and lowered their mortality rate by 29%.
Interestingly, the most benefit was seen 10 to 14 years after diagnosis. According to Dr. Mothaffar Fahed Rimawi of the Baylor College of Medicine in Houston, “…Almost half of breast cancer recurrences in this group occur beyond year 5, so it makes sense that longer treatment would be better.” (Azvolinsky, 2012)
Studies are currently underway to determine if continuing tamoxifen after 10 years offers an even greater benefit. In addition, researchers are studying whether 10 years of tamoxifen for post-menopausal women might trump the 5 years of aromatase inhibitors (AIs) this group currently takes – an option that would be very tempting to those women who suffer serious AI side effects.
And how about Herceptin – are two years of this targeted therapy better than the currently recommended 1 year?
No, say researchers. Analysis of data from an international study out of Belgium determined that 2 years of Herceptin offers the same benefit – in lowered recurrence risk and mortality – as 1 year.
Gene pathways may lead to new treatment
Triple negative breast cancer (TNBC), so-called because it’s neither estrogen/progesterone-receptive, nor HER2+, is particularly difficult to treat. Beyond chemotherapy, there’s no known long-term treatment to lower risk of recurrence and improve mortality.
But a new study from researchers at Vanderbilt University in Nashville identifies mutations in five well-known genetic pathways, mutations shared by 90% of TNBC patients in the study. And these five pathways “already have drugs either on the market or in development and could be targeted in clinical trials,” according to presenter Justin Balko, PharmD, PhD. (Smith, 2012)
What does this mean to you, as a survivor with TNBC? Nothing, at the moment. But the stage is being set for a future breakthrough in TNBC treatment.
According to Erica Mayer of Boston’s Dana-Farber Cancer Institute, commenting on the study, “In the future, women with triple-negative cancer will not be lumped together in clinical trials but will be differentiated – and treatments tested – on the basis of some of the genetic variations identified by Balko and colleagues.” (Smith, 2012)
TNBC more prevalent in younger women
A study out of Frankfurt, Germany revealed that 32% of women diagnosed with breast cancer under the age of 35 are dealing with TNBC. The number drops to 25% between ages 36 and 50; and 21% aged 51 and older.
The study presenter, Dr. Sibylle Loibl of the University of Frankfurt, noted that younger women are more likely to respond favorably to neoadjuvant chemotherapy – chemo delivered prior to surgery, to shrink the tumor – than older women.
Your takeaway, if you’re diagnosed with TNBC? The younger you are, the more insistent you should be on neoadjuvant chemotherapy.
Chemo brain – chemo not fully to blame?
A study from the University of Michigan School of Nursing in Ann Arbor found that women suffering from “chemo brain” – the forgetfulness, “fog,” and other cognitive issues so many survivors suffer during and after chemo – may have been building the groundwork for those issues before chemo even started.
Bernadine Cimprich, Ph.D, R.N., noted that fatigue-induced worry seems to be a major contributor to poor performances on cognitive tests. And that “the mental demand and stress of a breast cancer diagnosis could play a role in these early cognitive problems,” which in the study were identified in some patients prior to their starting chemo. Post-chemo, those same patients exhibited more severe symptoms than those who hadn’t shown any deficit prior to chemo. (Moore, 2012)
Bottom line: A breast cancer diagnosis can induce worry and fatigue, both of which contribute to future chemo brain. “It might be possible to diminish worry and fatigue and maintain strong brain function during the course of treatment using these interventions,” said Cimprich, listing mindfulness intervention, psychological support, cognitive behavior interventions, and exercise as possible chemo-brain preventives.
Good news for women facing a recurrence or metastasis
•For women with a local or regional recurrence of their hormone-receptive breast cancer (i.e., a recurrence confined to the breast or axillary lymph nodes), adding a new drug, “PD 0332991,” to one of the common aromatase inhibitors – Femara – showed an approximate 50% increase in benefit. PD 0332991 is still being tested in clinical trials, and not available to the public.
•Continuing tests show that for women with metastatic HER2+ breast cancer, cancer that hasn’t yet been treated, adding the drug Perjeta (pertuzumab) to the current regimen of Herceptin and chemotherapy reduces the risk of death by 34%. Perjeta received FDA approval last June.
Azvolinsky, A. (2012, December 05). SABCS: Extending tamoxifen therapy for breast cancer improves survival. Retrieved from http://www.cancernetwork.com/conference-reports/sabcs2012/content/article/10165/2118110
Koltrowitz, S. (2012, December 08). Roche breast cancer drug extends overall survival . Retrieved from http://www.reuters.com/article/2012/12/08/us-roche-perjeta-idUSBRE8B704T20121208
Moore, J. (2012, December 07). Cognitive problems may be present before chemotherapy in women with breast cancer. Retrieved from http://www.aacr.org/home/public--media/aacr-press-releases.aspx?d=2998
Smith, M. (2012, December 07). Gene study in triple-negative breast cancer is positive. Retrieved from http://www.medpagetoday.com/MeetingCoverage/SABCS/36331
Strait, J. (2012, December 07). Existing drugs may help more breast cancer patients. Retrieved from http://www.sciencedaily.com/releases/2012/12/121207085545.htm
Susman, E. (2012, December 07). Breast cancer 'different' in younger women. Retrieved from http://www.medpagetoday.com/MeetingCoverage/SABCS/36324
New breast cancer therapies improved survival. (2012, December 09). Retrieved from http://www.upi.com/Health_News/2012/12/09/New-breast-cancer-therapies-improved-survival/UPI-79171355031593/