Monday, August 31, 2009

PSA - Oncotype DX Test for Breast Cancer


Living with breast cancer is challenging for millions of women today. Some new ways of evaluating the likelihood that breast cancer will recur may allow doctors to determine who might benefit most from chemotherapy and other treatments.

With any cancer, the tumor cells divide uncontrollably. Cancer cells can then invade nearby tissues and spread through the bloodstream and lymphatic system to other parts of the body (called metastasizing). To kill cancer cells, doctors have routinely given patients with breast cancer the standard prescription: tumor removal via mastectomy or sometimes lumpectomy, usually followed by radiation and chemotherapy.

Until now, doctors have not been able to tell which women are at higher risk for breast cancer recurrence. Rather than take chances, every patient received the standard course of chemotherapy, which often has toxic side effects for many patients.

As we've learned more about cancer, researchers now realize that not all women with early breast cancer, including stage I and II, lymph node-negative breast cancer, actually benefit from adjuvant systemic therapy, which refers to chemotherapy, hormone therapy, and/or the drug trastuzumab (Herceptin).

Not All Breast Cancer Is the Same

More researchers are now thinking that not all breast cancers should be treated the same. Through findings from breast cancer clinical trials, scientists are discovering they can do a risk analysis of each woman's particular cancer and then base the outcome of breast cancer therapy (and specific type of therapy) upon the estimated risk of breast cancer recurrence.

Using a tool called the Recurrence Score, scientists are learning to quantify the likelihood of breast cancer recurrence in women with node-negative, estrogen receptor-positive (ER+) breast cancer and also predict the extent of chemotherapy benefit. While chemotherapy is necessary for some types of breast cancer, it may not be necessary for other types. And that's where the Oncotype DX test comes into play.

Breast Cancer and Oncotype DX

Oncotype DX is a diagnostic test that assesses the tumor tissue and estimates the likelihood that invasive breast cancer will return, or recur after treatment. By analyzing the expression pattern of certain genes in breast tumors, the Oncotype DX test can more precisely estimate a woman's risk of cancer recurrence when compared with the standard assessments doctors normally use to evaluate the risk of cancer returning.

The Oncotype DX screening test is performed on each tumor sample to get the Recurrence Score. The Oncotype DX test scores the breast tumor on 21 different genes involved in breast cancer and gives a Recurrence Score, or a number between 0 and 100 that shows a the chance of the breast cancer returning within 10 years of the original diagnosis.

The Recurrence Score is then categorized into one of three groups: low, intermediate, or high risk. For example, if a tumor has a Recurrence Score over 31, a high-risk score, this means there's a greater chance that the breast cancer will return. If a tumor gets a Recurrence Score of 18 or less, a low-risk score, this signals a lower chance that the breast cancer will return.
Using the Recurrence Score as a measure of risk, researchers now acknowledge a correlation between the score and the type of cancer treatment that is required. For example, with a low Recurrence Score, hormone therapy alone may successfully treat the woman's cancer. Alternately, a high Recurrence Score indicates a greater chance of the breast cancer returning, so the patient may benefit from adjuvant systemic therapy, including chemotherapy.

Who Might Benefit From the Oncotype DX Test?

The Oncotype DX test is recommended for breast cancer patients who are newly diagnosed, node-negative, estrogen receptor-positive, stage I or II, and who will be treated with tamoxifen, a selective estrogen-receptor modulator (SERM). Early findings from prospective trials indicate that a low Recurrence Score may determine which patients with ER+, node-negative breast cancer do not need chemotherapy.

The TAILORx TRIAL for Breast Cancer

More clinical trials are ongoing testing the Oncotype DX test. A groundbreaking clinical trial known as TAILORx is using the Oncotype DX test to see if some of the genes involved in breast cancer recurrence can also determine the need for chemotherapy -- and, more importantly, who will do better without it.The eventual results will help doctors recommend therapy that's based on the unique characteristics of each breast cancer tumor so they can maximize both effectiveness and safety in breast cancer treatment.

Use of the Oncotype DX test is limited to women with estrogen receptor-positive, node-negative breast cancer to help doctors determine if they can avoid the toxicity of chemotherapy if they have a low Recurrence Score. If women still want to undergo chemotherapy, that's a choice they can make with their oncologists.

Future Trends in Breast Cancer Treatment

In the near future, scientists predict the Recurrence Score may be used on other types of cancer, thus aiding doctors in prescribing individualized treatment that is safe and effective for cancer patients. A web-based tool called Adjuvant! Online allows doctors to incorporate the Recurrence Score from an Oncotype DX test to determine the benefit of chemotherapy in women with node-negative, ER-positive breast cancer. Using data from the Surveillance, Epidemiology and End Results (SEER) program of the National Cancer Institute, and from the year 2000 analysis of the Early Breast Cancer Trialists Collaborative Group (EBCTCG) findings, along with a proprietary formula, Adjuvant! Online can assist doctors in estimating each patient's prognosis and the benefit of adjuvant systemic treatment.

Reprinted from Web


  1. This is great info. You are like a walking WebMD. Seriously, I think a lot of women will benefit from this info. Is your Dr sharing it with you or are you finding it out on your own?

  2. TOTALLY finding it out on my own -- which is the UNBELIEVABLE aspect. I had to call my med-onc and request that he ask for this test to be done on my tumor. To which he agreed. Regardless of his answer I would have had it done by someone.

    What floors me, is that in my research my tumor and diagnosis are a text-book fit to run this test. I would have never known about it, however, but for my ongoing research to find answers to my questions outside of the med-pro squad. And, my med-onc is not only fully aware of my perspective on cookie-cutter treatment, but one of the top recommended med-oncs in our metropolitan area.

  3. Hey, Tamera - I just heard the news from Larry, who linked me here. It's hard news, and I hope you & your family are all managing this OK. Sure sounds so, from what you write here.

    I'm not surprised you're having to research this all yourself; it continually disappoints me how little MDs know (or is it, that they're willing to disclose?) about their own specialties. I always wonder, though, whenever I have to confront an MD or a health insurance carrier: what happens to the patients out there, who don't have graduate educations, health insurance, a support structure, and the ability to act as their own advocate? Don't answer that.

    Good on you for taking the approach you are, and putting it out here on the Interwebs. I'll be lurking as connectivity permits.

    All the best, Tamera -
    Marianne Smith
    s/v Gallant Fox
    Mazatlan, Mexico

  4. You are definitely taking the right approach, TC. The one key lesson my family learned after my dad's abrupt departure from this world due to lung cancer, is that YOU MUST MANAGE your own healthcare. No one else will, and certainly not the medical profession. Both my bio-mum and my husband's mum were nurses, and have some stories about med care which are mind blowingly scary. Not to paint all in the profession with a black brush, but enough goes on (or rather doesn't go on) that is in the best interests of the patient.

    So much so that when I was having surgery back in the US a few years ago, my bio-mum took a leave of absence to come up to Virginia to take on all my nursing care. You may think this is lovely example of maternal instinct, but if you knew my mother, you know that she considered it an absolute necessity to be in the hospital 24/7 as she trusted no one on the med staff.

    Managing your treatment and care as you are TC will no doubt increase your survival odds. Of that, I'm absolutely convinced.