Some breast cancer patients may not need chemotherapy

Posted at 5:21 AM, Jun 25, 2018
and last updated 2018-06-25 06:21:51-04

Breast cancer doctors are excited about the results of a study involving 10,000 women.

Its findings?  Many breast cancer patients may be able to skip the chemotherapy process.

The study affects many women who have the most common type of early-stage breast cancer.

The study is the largest ever done of breast cancer treatment, and the results are expected to spare up to 70,000 patients a year in the United States, and many more elsewhere, the ordeal and expense of these drugs. 

“It is a 21-gene breast cancer assay test. They look at 21 genes that have been identified to be associated with an increased risk of a woman developing recurrence of her breast cancer,”said radiation oncology specialist Dr. Gerard Voorhees.

The results of the trial suggest that up to 85 percent of women with early breast cancer can be spared chemotherapy especially those over 50 years of age.

"That’s why it is always good to think of some of the warning signs. A woman notices a change in her breast, either increased redness or induration of the skin, dimpling of the skin, obviously a lump, or if the nipple becomes inverted, breast red and swollen, then they should see their physician right away” said Dr. Voorhees.

Dr. Gerard Voorhees, with the Corpus Christi Medical Center Radiation Oncology, says he has seen the impact chemotherapy has on cancer patients physically, emotionally and economically.

“This is great news. Women with early stage breast cancer who are estrogen receptor positive, who have no lymph nodes spread, who are negative for a protein called a human epidermal growth factor 2 protein, and who are at low to intermediate risk for recurrence, do not need chemotherapy, ”said Dr. Voorhees.

For patients, this means taking pills every day for about five years, instead of going through time consuming and painful treatments at the hospital.

Women concerned about their own risk of breast cancer recurrence should speak to their personal physician.

Genetic tests can help determine treatment for breast cancer patients with smaller-sized tumors that have not spread to the lymph nodes.

Of the more than 250,000 women in the U.S. expected to be diagnosed with breast cancer, the new findings could benefit more than 63,000 with non-invasive, or early stage, disease.

Women with cancer are given scores that come from genetic tests that analyze the tumors and look for the presence of 21 genes that have been associated with a high likelihood of recurrence. Until now, doctors didn’t know for sure whether to offer chemotherapy to a large percentage of patients with early stage cancer.

Earlier this month, a new study presented at the American Society of Clinical Oncology (ASCO) meeting found that a large amount of women with breast cancer do not actually benefit from chemotherapy.

Many women with early-stage breast cancer who would receive chemotherapy under current standards do not actually need it, according to a major international study that is expected to quickly change medical treatment.

The study found that gene tests on tumor samples were able to identify women who could safely skip chemotherapy and take only a drug that blocks the hormone estrogen or stops the body from making it. 

The hormone-blocking drug tamoxifen and related medicines, called endocrine therapy, have become an essential part of treatment for most women because they lower the risks of recurrence, new breast tumors and death from the disease.

The results indicate that now we can spare chemotherapy in about 70 percent of patients who would be potential candidates for it based on clinical features. The study, called TAILORx, is being published by The New England Journal of Medicine and was to be presented at a meeting of the American Society of Clinical Oncology in Chicago. 

The study began in 2006 and was paid for by the United States and Canadian governments and philanthropic groups. Genomic Health, the company that makes the gene test, helped pay after 2016.

Patients affected by the new findings include women who, like most in the study, have early-stage breast tumors measuring one to five centimeters that have not spread to lymph nodes; are sensitive to estrogen; test negative for a protein called HER2; and have a score of 11 to 25 on a widely used test that gauges the activity of a panel of genes involved in cancer recurrence.

The test, available since 2004, gives scores from 0 to 100. It costs about $3,000, and insurance usually covers it.

Breast Cancer Signs and Symptoms

  • Swelling of all or part of a breast (even if no distinct lump is felt)
  • Skin irritation or dimpling (sometimes looking like an orange peel)
  • Breast or nipple pain.
  • Nipple retraction (turning inward)
  • Redness, scaliness, or thickening of the nipple or breast skin.
  • Nipple discharge (other than breast milk)

Doctors highly encourage anyone with symptoms to see their physician right away. The USPSTF recommends that women who are 50 to 74 years old and are at average risk for breast cancer get a mammogram every two years. Women who are 40 to 49 years old should talk to their doctor or other health care professional about when to start and how often to get a mammogram.

The recurrence score based on the 21-gene breast cancer assay predicts chemotherapy benefit if it is high and a low risk of recurrence in the absence of chemotherapy if it is low; however, there is uncertainty about the benefit of chemotherapy for most patients, who have a midrange score.

Doctors performed a prospective trial involving 10,273 women with hormone-receptor–positive, human epidermal growth factor receptor 2 (HER2)–negative, axillary node–negative breast cancer. Of the 9719 eligible patients with follow-up information, 6711 (69%) had a midrange recurrence score of 11 to 25 and were randomly assigned to receive either chemoendocrine therapy or endocrine therapy alone. 

The trial was designed to show non-inferiority of endocrine therapy alone for invasive disease–free survival (defined as freedom from invasive disease recurrence, second primary cancer, or death).

Endocrine therapy was non-inferior to chemoendocrine therapy in the analysis of invasive disease–free survival (hazard ratio for invasive disease recurrence, second primary cancer, or death [endocrine vs. chemoendocrine therapy], 1.08; 95% confidence interval, 0.94 to 1.24; P=0.26). At 9 years, the two treatment groups had similar rates of invasive disease–free survival (83.3% in the endocrine-therapy group and 84.3% in the chemoendocrine-therapy group), freedom from disease recurrence at a distant site (94.5% and 95.0%) or at a distant or local–regional site (92.2% and 92.9%), and overall survival (93.9% and 93.8%). 

The chemotherapy benefit for invasive disease–free survival varied with the combination of recurrence score and age (P=0.004), with some benefit of chemotherapy found in women 50 years of age or younger with a recurrence score of 16 to 25.

Adjuvant endocrine therapy and chemoendocrine therapy had similar efficacy in women with hormone-receptor–positive, HER2-negative, axillary node–negative breast cancer who had a midrange 21-gene recurrence score, although some benefit of chemotherapy was found in some women 50 years of age or younger.