The Best Breast Cancer Breakthroughs of 2020

Breast cancer is still one of the leading causes of disease and death in women, both in the United States and worldwide. Approximately 276,480 new cases of invasive breast cancer will be diagnosed in the US alone during 2020, along with 48,530 cases of non-invasive or in situ breast cancer. Around the world, more than 2 million cases of breast cancer are diagnosed each year.  Breast cancer is the second most common type of cancer affecting American women, only behind skin cancer. And let’s not forget that breast cancer can also affect men— approximately 2,260 men will have been diagnosed with male breast cancer by the end of 2020.

With the COVID-19 pandemic, 2020 has been an especially scary year for those affected by breast cancer. Thankfully, new discoveries are being made every single day. Newer treatments, and screening and prevention strategies have progressively improved the survival rates for patients with breast cancer. This year:

  • The FDA approved several promising drugs
  • Other medications showed great potential in clinical trials
  • New therapeutic alternatives were successfully tested and could revolutionize the standard of care for breast cancer.

Here are some of the most exciting breast cancer breakthroughs of 2020.

1. TTC-352 Shows Promise for Metastatic Breast Cancer

What is this breakthrough?

A new drug called TTC-352, developed by researchers at the University of Illinois Chicago shows promising antitumor activity in patients who have ER+ metastatic breast cancer which has previously stopped responding to at least two hormonal therapies. The drug is a selective human estrogen receptor partial agonist, which impedes the effects of estrogen on ER+ breast cancer, "starving" the tumor so it stops growing. The study on TTC-352 found that:

  • It was able to stabilize the disease and prevent progression in patients with metastatic breast cancer for several months.
  • No toxic side effects were recorded, even in patients who received high doses of the medication.  

"This is very encouraging because these participants were at an advanced stage of their disease, and we saw that their cancers stopped growing for a significant amount of time," said Debra Tonetti, one of the authors on the paper. Tonetti is also a professor at UCI and a member of the University of Illinois Cancer Center.


Who can this breakthrough help?

Approximately 80 percent of all cases of breast cancer are ER+, meaning that they have specific receptors for estrogen. These tumors grow in the presence of estrogen, which is one of the main hormones that naturally occur in women’s bodies. Patients who have this type of cancer are usually placed on hormone therapy to keep the tumor from growing.

But nearly half of all women treated with hormone therapy will stop responding to the treatment at some point, since cancer can become resistant to these drugs. The new drug could become an  alternative to tamoxifen, which is commonly used to treat breast cancer — but unlike tamoxifen, TTC-352 has been found to pose a lower risk of developing uterine cancer.


“While there are many treatments for breast cancer, about half of women with ER-positive cancers become resistant to hormone therapy, leaving them with few treatments other than chemotherapy, with its well-known toxic side effects,” said Tonetti.


The development and eventual approval of TTC-352 could provide patients and their medical team with a new weapon to combat advanced breast cancer and serve as an alternative to traditional chemotherapy in these cases.


2. Single Dose Radiotherapy During Surgery as Effective as Conventional Radiotherapy for Early Breast Cancer

What is this breakthrough?

A study published in the journal BMJ found evidence that a single dose of radiotherapy, administered during lumpectomy procedures can be just as effective as traditional whole-breast radiotherapy for patients with early-stage invasive ductal carcinoma.

The study followed more than 2,000 patients with early-stage breast cancer over the course of several years. Researchers found that:

  • Patients who were given a single dose of targeted intraoperative radiotherapy (IORT) had similar outcomes to patients who received whole-breast external beam radiotherapy after surgery.
  • Patients in both groups had comparable long-term rates of survival and mortality — however, patients who received IORT had significantly lower rates of non-breast cancer mortality


What does this breakthrough mean for the future?

Whole-breast radiotherapy is still the standard of care for early-stage breast cancer and additional research is still needed to confirm these findings. But in the future, these studies could lead to new treatment guidelines that are easier to tolerate for patients


Who can this breakthrough help?

This finding could be very beneficial for women with early-stage breast cancer, since they may not have to receive whole-breast radiotherapy after lumpectomy surgery. Whole-breast radiotherapy has been part of the traditional approach to treating early-stage breast cancer for many patients throughout the years.

As its name suggests, whole-breast radiation therapy requires exposing the entire breast to external beam radiation. This means that the technique also exposes healthy tissue and other organs — such as the heart and lungs — to significant amounts of radiation. Additionally, whole-breast radiotherapy is usually administered 5 days a week on a schedule that can last approximately 3 to 7 weeks. 

This breakthrough could:

  • Make treatment easier for patients after lumpectomy procedures, allowing them to have more time to recover from the procedure and requiring fewer trips to the hospital.
  • It could also mean that patients will be exposed to lower amounts of radiation during their treatment.


3. FDA Approves Combo Injection for HER2-Positive Breast Cancer

What is this breakthrough?

A fixed-dose combination of Herceptin (trastuzumab), Perjeta (pertuzumab), and hyaluronidase-zzxf received FDA approval in June, 2020. This combination is meant to be used to treat HER2-positive breast cancer in combination with chemotherapy. Phesgo can be used for both early-stage and metastatic breast cancer.

The combo injection is manufactured by Genentech and goes by the brand name Phesgo. It’s available as a single-dose vial, and it’s administered as a subcutaneous injection which only takes a few minutes. Traditional IV infusions of Herceptin and Perjeta, on the other hand, can take anywhere between 60 and 150 minutes. Phesgo can be administered in a clinical setting or at home— an option that can be much more comfortable and safe for patients, particularly considering the COVID-19 pandemic


How do these drugs work?

Herceptin and Perjeta are HER2 inhibitors that are commonly used to treat HER2-positive breast cancer. HER2 is a protein called human epidermal growth factor receptor 2 (HER2) which is expressed on the outer surface of human cells. This protein promotes tissue growth, and some tumors (including breast, stomach, ovarian, and pancreatic tumors, among others) can produce elevated levels of HER2.

  • Herceptin and Perjeta are antibodies that work by attaching themselves to the HER2 protein and blocking the chemical signals that lead to tumor growth.
  • Hyaluronidase-zzxf is an enzyme that helps the body absorb the other two drugs more effectively.


Who can this breakthrough help?

Phesgo can provide a shorter, more comfortable route of administration for patients with HER2-positive breast cancer — who make up approximately one fifth of all breast cancer patients. It can reduce the administration time of these medications from 1-2.5 hours to a mere 5 minutes.

This combo injection can also reduce patients’ need to go to the hospital for their treatments, which can help keep breast cancer patients safe at home during the current pandemic.

4. FDA-Approved Tukysa Can Prevent Progression of Brain Metastases

What is this breakthrough?

Tukysa (tucatinib) was approved by the FDA in April, 2020, to be used in combination with Herceptin (trastuzumab) and Xeloda (capecitabine) to treat HER2-positive breast cancer. This drug regime can be used to treat metastatic breast cancer, or locally advanced cases of breast cancer that can’t be entirely removed through surgery, also known as unresectable.

  • The HER2CLIMB trial showed that adding Tukysa to Herceptin and Xeloda reduced both the risk of tumor growth and breast cancer mortality by 46 percent, increasing overall survival rates.
  • For patients with brain metastases, the drug combination reduced the risk of death, and increased progression-free survival as the primary outcome. These results are very encouraging for patients with brain metastases, who often don’t have a lot of therapeutic options available.


How does this drug work?

Tukysa belongs to a class of drugs called tyrosine kinase inhibitors (TKIs). Tyrosine kinases are enzymes that normally help regulate many cell processes, such as cell growth, division, metabolism, and differentiation. When tyrosine kinases become dysregulated, they can lead to uncontrolled cell division, leading to different types of cancer cancer.

  • Tyrosine kinase inhibitors work by targeting these enzymes to inhibit the growth of cancerous cells.
  • Tukysa is a pill that’s taken orally, and it’s administered to patients who have previously received one or more anti-HER2 treatments for advanced breast cancer.


Who can this breakthrough help?

Tukysa can help patients with metastatic breast cancer which has spread to their brains by helping slow down or stop the progression of these lesions. In time,Tukysa could become a new standard of care for patients with advanced HER2-positive breast cancer, with or without brain metastases.


5. Researchers Find A Way to “Switch Off” Gene that Causes Aggressive Breast Cancer

What is this breakthrough?

A team of researchers at Tulane University School identified the gene TRAF3IP2, which plays an important role in the development of triple negative breast cancer (TNBC). The study compared the results of suppressing TRAF3IP2 versus another gene called Rab27a.

  • They found that suppressing either gene in mice slowed tumor growth. However, suppressing Rab27a still allowed a small number of cancer cells to spread. But when TRAF3IP2 was suppressed, they found no evidence of any type of micrometastases for up to a year after treatment.
  • Other studies found that silencing this gene could also benefit patients with glioblastoma, a fast-growing and very aggressive type of brain cancer.

 "Targeting TRAF3IP2 suppresses tumor growth and spread, and interfering with it both shrinks pre-formed tumors and prevents additional spread. This exciting discovery has revealed that TRAF3IP2 can play a role as a novel therapeutic target in breast cancer treatment, said team leader Dr. Reza Izadpanah.


What does this breakthrough mean for the future?

TNBC accounts for approximately 10 to 15 percent of all cases of breast cancer, and it’s considered to be the most aggressive type of breast cancer. TNBC is called “triple-negative” because it doesn’t have receptors for estrogen or progesterone, and it doesn’t produce high levels of HER2. This type of breast cancer can grow and spread very rapidly, and it usually has very limited therapeutic options. TNBC is also more likely to reoccur after treatment than other types of breast cancer.

The findings in this study have led to the research team working on obtaining FDA approval for future clinical trials.


Who can this breakthrough help?

Although further research is still needed, this discovery is incredibly exciting for the scientific community, especially considering that TNBC can be a devastating diagnosis. Hopefully, future trials will be successful and patients with TNBC and other types of cancer will be able to benefit from this breakthrough in the near future.


There’s still a long way to go in the battle against breast cancer, but it’s encouraging to realize that each year brings new innovative treatments of this disease, and a deeper understanding of what we can do to prevent and manage it. We can’t wait until it’s time to write about even more breakthroughs for next year’s article!


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