ASCO Annual Meeting 2017: News on Breast Cancer, Prostate Cancer, TRK Fusion Protein Inhibition, Using Blood Tests to Screen for Cancer, and Genomic Testing

2017 ASCO Annual Meeting. #ASCO17
June 3, 2017
Greg Guthrie, ASCO staff

“Although we span many disciplines and professions,” says ASCO President Daniel F. Hayes, MD, FACP, FASCO, “we are a single community with a singular focus: to provide better care for patients at risk for or with cancer.” That is why the theme of this year’s American Society of Clinical Oncology (ASCO) Annual Meeting is Making a Difference in Cancer Care WITH YOU. Watch a patient education video with Dr. Hayes explaining why the ASCO Annual Meeting is so significant.

More than 38,000 oncology professionals from around the world are at the ASCO Annual Meeting, presenting and discussing the latest research in treatment and patient care. Learn about the research released today:

  • Pregnancy after breast cancer does not increase the risk of recurrence

  • Abiraterone is shown to help men with advanced prostate cancer live longer in 2 studies

  • New targeted therapy may treat many types of cancer in adults and children

  • New blood test technology shows promise as tool for finding cancer early

  • Routine genetic testing of cancer is possible, but only some patients benefit

Pregnancy after breast cancer does not increase the risk of recurrenceshare on twitter

A large study of breast cancer survivors has found that pregnancy does not increase the risk of recurrence. This includes women with estrogen receptor (ER)-positive breast cancer, which is the most common type of breast cancer. Of the 1,207 women in the study, about half had ER-positive cancer and more than 40% had a complicated diagnosis, including a large tumor or cancer that has spread to nearby lymph nodes.

Breast cancer is the most common cancer in women of reproductive age. Because many women are now choosing to have children at an older age than in the past, this means that many women with breast cancer are diagnosed before they plan to have children. Survivors have had serious concerns about whether pregnancy may shorten their lives. In particular, women with ER-positive breast cancer have worried about the role of estrogen in that cancer’s growth and the natural rise in estrogen levels during pregnancy. Of all cancer survivors, breast cancer survivors are the least likely to have a baby.  

In this study, the median follow-up was 10 years from the cancer diagnosis. The median is the midpoint, meaning that the health of half of the women was tracked by researchers for less than 10 years and the other half were followed for more than 10 years. After successful treatment for earlier stage breast cancer, 333 of them became pregnant and 874 did not. After that 10-year period, women who did or did not become pregnant had the same rates of survival. Further analysis showed that none of the following conditions affected how long these women lived: whether the pregnancy was completed, how much time had passed since the cancer diagnosis, and whether the women had breastfed their babies. In fact, survivors with ER-negative breast cancer who became pregnant had a 42% lower chance of dying than those who did not become pregnant.

This was a large study, but it had limited information about breastfeeding, using assisted reproductive technologies, such as in vitro fertilization, and human epidermal growth factor receptor 2 (HER2) status. Still, the results suggest that breastfeeding is possible, even after breast surgery. Other research is planned that further examines some of these topics, as well as whether these findings apply to women with BRCA-related breast cancer.

Read a full-text transcript of this animation. 

What does this mean? Survivors and doctors have worried for a long time that pregnancy could increase the chances of breast cancer coming back, especially for women with ER-positive cancer. This study shows that pregnancy does not increase the risk of a breast cancer recurrence.

“Our findings confirm that pregnancy after breast cancer should not be discouraged, even for women with ER-positive cancer. However, when deciding how long to wait before becoming pregnant, patients and doctors should consider each woman’s personal risk for recurrence, particularly for women who need adjuvant hormone therapy.”

— lead study author Matteo Lambertini, MD
Institut Jules Bordet
Brussels, Belgium


Abiraterone is shown to help men with advanced prostate cancer live longer in 2 studiesshare on twitter

Results from 2 different clinical trials show that adding abiraterone acetate (Zytiga) to the standard treatment of androgen-deprivation therapy (ADT) for advanced prostate cancer helps men live longer.

Treatments for earlier stage prostate cancer have high success rates, but current treatment options for metastatic prostate cancer are limited. ADT is a standard treatment because it stops a man’s testicles from making testosterone, a hormone that helps prostate cancer grow. However, the body’s adrenal glands and prostate cancer cells themselves can still make some testosterone. Abiraterone stops the body from producing any testosterone.

Abiraterone is already approved by the U.S. Food and Drug Administration (FDA) to treat prostate cancer that has worsened even after treatment with ADT. These 2 studies focused on using the drug for specific groups of patients in combination with ADT. In each study, participants were divided into 2 groups, where 1 group received ADT treatment alone and the other received ADT plus abiraterone and prednisone or prednisolone. Prednisone or prednisolone was given along with abiraterone in both studies, since they are known to manage certain side effects of abiraterone, such as high blood pressure.

LATITUDE Study: Abiraterone helps men with high-risk, metastatic prostate cancer

A phase III clinical trial called LATITUDE found that adding abiraterone to ADT slowed the time that advanced prostate cancer worsened, from nearly 15 months to 33 months. The 1,200 participants in this study were newly diagnosed with prostate cancer that had already spread beyond the prostate to other parts of the body, called metastatic cancer. There were also additional factors that classified the disease as “high risk.”

After a median follow-up period of about 30 months, men in the abiraterone group had a 38% lower risk of dying than those who received ADT alone. Median means the midpoint or the middle. More than half of the patients who received abiraterone were still alive at the time that the study results were being reviewed, while half of the men who received standard ADT had died within about 35 months. The group receiving abiraterone had a 53% lower risk of the cancer worsening, and cancer growth was delayed by a median of 18 months.

“We had been treating metastatic prostate cancer the same way for 70 years until docetaxel chemotherapy was shown to improve survival in 2015, and now in 2017 we show abiraterone is also helping patients live longer. The next step is to see if adding abiraterone on top of docetaxel offers further benefit.”

— lead study author Karim Fizazi MD, PhD
Gustave Roussy Cancer Institute, University Paris-Sud
Villejuif, France


STAMPEDE Study: Abiraterone helps men with locally advanced and metastatic prostate cancer

Results from an ongoing clinical trial called STAMPEDE compared standard ADT with ADT plus abiraterone and prednisolone in men with high-risk prostate cancer that had spread nearby, called locally advanced, or was metastatic at the time of diagnosis. The 3-year survival rate was 83% in the group receiving abiraterone, compared with 76% in the group that received ADT alone. Adding abiraterone to ADT lowered the chance of dying by 37%.

Conducted in the United Kingdom and Switzerland, the study included nearly 2,000 men who were all starting ADT for the first time. Men who had locally advanced cancer could also receive radiation therapy in addition to ADT.

“Abiraterone not only prolonged life, but also lowered the chance of relapse by 70% and reduced the chance of serious bone complications by 50%. Based on the magnitude of clinical benefit, we believe that the upfront care for patients newly diagnosed with advanced prostate cancer should change.”

— lead study author Nicholas James, BSc, MBBS, PhD
Queen Elizabeth Hospital
Birmingham, United Kingdom


In both prostate cancer studies, the researchers looked at side effects of adding abiraterone and prednisone or prednisolone to ADT. Both studies noted that some severe side effects were more common in the abiraterone-treated group, including high blood pressure, low potassium, and liver enzyme problems. Due to this, there could be a need for caution when using abiraterone in men who have an increased risk for heart problems, such as those with diabetes.

What does this mean? Adding abiraterone to standard ADT could help men with a diagnosis of advanced prostate cancer live longer.

New targeted therapy may treat many types of cancer in adults and childrenshare on twitter

Scientists may have developed the first targeted cancer medicine taken by mouth that is not specific to a certain cancer type but instead focuses on a specific genetic abnormality found in a range of tumor types.

Larotrectinib (LOXO-101) stops tropomyosin receptor kinase (TRK) fusion proteins. TRK fusion proteins are made when a TRK gene in a cancer cell fuses with 1 of many other genes. They signal the cancer cells to keep growing and dividing. These proteins are rare in many common cancers but appear in more than 90% of some rare cancers.

The patients in this study had locally advanced or metastatic cancer, including specific types of colon, lung, pancreatic, thyroid, salivary gland, and gastrointestinal cancers, as well as melanoma and sarcoma. Researchers reviewed data from 3 early clinical trials that involved 43 adults and 12 children. They found that larotrectinib worked in 38 (76%) of the first 50 patients who had been in the study long enough to have 2 scans to confirm results. This patient group included 17 different types of cancer. In 79% of the patients for whom larotrectinib worked, the medication was still effectively treating the cancer after 12 months. For some patients, the drug has been continuing to work for more than 2 years. In addition, 3 of the children were not able to have surgery for sarcoma at the time they joined the study, but treatment with larotrectinib shrank the tumors enough to make surgery possible.

The most common side effects of larotrectinib were fatigue and mild dizziness, which was expected because normal TRK protein plays a role in controlling the sense of balance. No one stopped treatment because of the side effects.

What does this mean? Larotrectinib may be a new treatment option in both adults and children for a variety of advanced cancers that have TRK fusion proteins.

“TRK fusions are rare, but occur in many different cancer types. In fact, at this point it is hard to find a cancer type where TRK fusions have not been reported. These findings embody the original promise of precision oncology: treating a patient based on the type of mutation, regardless of where the cancer originated. We believe that the dramatic response of tumors with TRK fusions to larotrectinib supports widespread genetic testing in patients with advanced cancer to see if they have this abnormality.”

— lead study author David Hyman, MD
Memorial Sloan Kettering Cancer Center
New York, New York


New blood test technology shows promise as a tool for finding cancer earlyshare on twitter

Results from a new study show a new high-intensity technology could be a step forward in the effort to create a blood testing method that can find cancer in a person before a tumor is discovered or tested.

All the DNA contained in a person’s cells makes up that person’s genome. A study of 124 patients with advanced breast, non-small cell lung, and prostate cancers used a new, high-intensity genomic sequencing approach to find circulating tumor DNA in the blood. “Circulating tumor DNA” is a phrase used to describe the tiny pieces of genetic material that dying cancer cells shed into the bloodstream. Tumor DNA comprises only a small portion of the DNA that is found in the blood; most of the DNA fragments are shed by normal cells.

To test the effectiveness of this new method, researchers compared the results of the blood test with the results of tissue biopsy. In 89% of the patients, at least 1 genetic change found in the tumor was also found by the blood test. Researchers found a total of 864 genetic changes in tissue samples, and 73% of those genetic changes were also found in the blood.

The high-intensity sequencing approach scans a very broad area of the genome and reads each area multiple times, yielding about 100 times more data than other sequencing methods. This technology is not available for use outside of research, and this study was done to test its effectiveness in the effort to eventually create a tool to find cancer early.

When a person is already known to have cancer, testing for circulating tumor DNA in the blood is called a “liquid biopsy.” Research continues on liquid biopsies for the purpose of helping monitor cancer growth or finding specific genetic mutations that can be matched to available drugs that target those mutations.

What does this mean? In the future, doctors may be able to use a blood test to find cancer before it causes signs or symptoms. This could help doctors diagnose cancer earlier.

“Our findings show that high-intensity circulating tumor DNA sequencing is possible and may provide invaluable information for clinical decision-making, potentially without any need for tumor tissue samples. This study is also an important step in the process of developing blood tests for early detection of cancer.”

lead study author Pedram Razavi, MD, PhD
Memorial Sloan Kettering Cancer Center
New York, New York

Routine genetic testing of cancer is possible, but only some patients benefitshare on twitter

Data from a French study called ProfiLER show that when genetic testing is available, some people with cancer may live longer when such testing discovers a molecular target in the tumor that can be treated with a drug that aims at that target, called targeted therapy. For patients who received targeted therapy as a result of genomic testing in this study, nearly 54% were still alive after 3 years, compared with 46% of patients who did not receive targeted therapy. The 5-year survival rate was also higher for patients who received targeted therapy (34.8% vs. 28.1%).

Genomic testing is being done in a growing number of people with advanced cancer, but comprehensive genomic testing is currently not a part of routine cancer care.

In the ProfiLER study, 1,944 tumors have been analyzed across a number of cancer types, including colorectal, gynecologic, breast, brain, and head and neck cancers, as well as sarcoma. Genetic changes that could be treated with current targeted therapies, called “actionable” mutations, were found in more than half of those tumor samples. A board of experts met weekly to review the results of genomic tests and to provide recommendations for targeted therapy when actionable mutations were found. The expert board recommended targeted therapy for 676 patients, and of those, 143 received treatment, mostly through clinical trials. The 533 patients who did not receive treatment could not because of their overall health, the eligibility criteria of the available clinical trials, or the difficulty of getting the medications.  

What does this mean? This study shows that routine genomic testing can identify more patients who may benefit from targeted therapy, although the actual number of people who may receive treatment is smaller. If a patient can receive a matched targeted therapy, then he or she has a better chance of living longer.

“This study confirms that comprehensive genomic profiling can be performed in routine practice to select patients for targeted cancer therapies. The technology is widely available and requires only a small amount of DNA. Theoretically, we could do this testing for every patient in France.”

—lead study author Olivier Tredan, MD, PhD
Centre Leon Berard
Lyon, France

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