From Mark Levine, the Doc with the Pink Tights
Progress in the Fight against Cancer

I am frequently asked the questions “Doc, is there any progress being made in the fight against breast cancer?” and “when will it be cured?” Wow! These are difficult questions to answer. I usually choose my words carefully and respond:

  1. Cancer is many diseases and what you hear on the radio about a particular cancer or read about it in the newspaper may not apply to your own cancer.
  2. I often use an analogy from baseball to explain progress in cancer research, which then leads to changes in clinical practice. There are very few homeruns but the goal is to hit singles and doubles and move the players around the bases. For those of you who are not into baseball, this means slow steady progress which is incremental.
  3. Finally, I explain that 35 years ago when I started practicing as a medical oncologist, I had very few options to offer my patients with breast cancer that had metastasized. Over the years, many new agents have become available to fight and control the cancer.

These days there is much hype about “precision medicine.” It is a hot area for research. It means that drugs can be targeted specifically to a genetic or molecular abnormality in a cancer and the drugs will work against that cancer. In other words, the drug is being tailored to a patient’s cancer and a patient can be spared side effects if it is known that the drug will not work ahead of time.

It is interesting that in the treatment of breast cancer, we have been using precision medicine for many years. It is standard to test breast cancer tissue for estrogen receptor (ER) and Her2.
Hormone therapy, such as tamoxifen or an aromatase inhibitor, is only given if the cancer is ER positive. Similarly, Herceptin is only given if the cancer tests positive for Her2.

However, there are many situations in breast cancer treatment where we use broad coverage treatment because we cannot predict whether the treatment will work. Hence, we treat many patients to benefit a few.

You may have heard about sequencing the breast cancer. This means examining all the genes in a breast cancer and identifying those that are changed (the medical word is mutated). Unfortunately, at this juncture, there are too many mutations that differ between each patient, and we do not have drugs to target most mutations.

I want to mention a class of new drugs that in the last year or so has had a major impact on the treatment of breast cancer and is a game changer.

We usually treat metastatic ER positive breast cancer with endocrine (hormone) therapy. A new class of drugs called CDK4/6 inhibitors, which are given orally, have become available. They help block the movement of cancer cells into active growth, referred to as the cell cycle. Endocrine therapy also works best on cancer cells that are not growing in the cell cycle.

One of the drugs is called Palbociclib (Pfizer) and another is Ribociclib (Novartis). Clinical trials have shown that adding these drugs to usual endocrine treatment can control the cancer better than endocrine treatment alone and delay its growth substantially.

Clearly, research has had a significant impact on the lives of patients with breast cancer. It has resulted in many more options for oncologists to use in treatment. I am left with a sense of optimism and hope for the future. But there is still much work to be done.