New skin gel fights breast cancer without blood clot risk

July 15, 2014

A gel form of tamoxifen applied to the breasts of women with noninvasive breast cancer reduced the growth of cancer cells to the same degree as the drug taken in oral form but with fewer side effects that deter some women from taking it, according to new Northwestern Medicine® research.

Tamoxifen is an oral drug that is used for prevention and as therapy for non-invasive breast cancer and invasive cancer.

Because the drug was absorbed through the skin directly into breast tissue, blood levels of the drug were much lower, thus, potentially minimizing dangerous side effects—blood clots and uterine cancer.

The was tested on women diagnosed with the non-invasive cancer ductal carcinoma in situ (DCIS) in which abnormal cells multiply and form a growth in a milk duct. Because of potential side effects, many women with DCIS are reluctant to take oral tamoxifen after being treated with breast-saving surgery and radiation even though the drug effectively prevents DCIS recurrence and reduces risk of future new breast cancer.

The paper was published July 15 in the journal Clinical Cancer Research.

"Delivering the drug though a gel, if proven effective in larger trials, could potentially replace oral tamoxifen for breast and DCIS and encourage many more women to take it," said lead author Seema Khan, M.D., a Northwestern Medicine® surgical oncologist. "For breast cancer prevention and DCIS therapy, effective drug concentrations are required in the breast. For these women, high circulating drug levels only cause collateral damage."

Khan is a professor of surgery and the Bluhm Family Professor of Cancer Research at Northwestern University Feinberg School of Medicine. She also is a surgeon at Northwestern Memorial Hospital and co-leader of the breast cancer program at the Robert H. Lurie Comprehensive Cancer Center of Northwestern University

"The gel minimized exposure to the rest of the body and concentrated the drug in the breast where it is needed," Khan said. "There was very little drug in the bloodstream which should avoid potential blood clots as well as an elevated risk for uterine cancer."

Women who have completed surgery and radiation are given oral tamoxifen for five years to reduce the risk of the DCIS recurring at the same place and of new breast cancer appearing elsewhere in the same breast or the other breast. Tamoxifen is an anti-estrogen therapy for a type of breast cancer that requires estrogen to grow.

Khan and colleagues conducted a phase II clinical trial to compare the effects of the gel, 4-OHT, with oral tamoxifen. They found after six to 10 weeks of gel application that the reduction in a marker for cancer cell growth, Ki-67, in breast tissue was similar to that of oral tamoxifen. The scientists also found equal amounts of 4-OHT present in the of patients who used the gel or took the oral , but the blood levels of 4-OHT were more than five times lower in those who used the gel.

The reduction in the levels of 4-OHT in the blood also was correlated with a reduction in proteins that cause blood clots.

The study involved 26 women, ages 45 to 86, who had been diagnosed with DCIS that was sensitive to estrogen (estrogen-receptor-positive DCIS). Half the women received the gel, which they applied daily, and half the , which they took daily.

The gel application may also be more effective for some women. Oral tamoxifen doesn't help all women who take it because it needs to be activated in the liver by specific enzymes and about a third of women lack these enzymes, Khan said. These may not receive full benefits from the pill.

Explore further: Can topical skin gel shrink some breast cancer tumors?

Related Stories

Can topical skin gel shrink some breast cancer tumors?

June 24, 2011
Can a gel applied to the skin of a woman's breast provide the same cancer-fighting benefits as a pill taken by mouth but reduce the side effects of the medicine?

Can gel shrink some cancer tumors?

July 8, 2011
(Medical Xpress) -- Can a gel applied to the skin of a woman's breast provide the same cancer-fighting benefits as a pill taken by mouth but reduce the side effects of the medicine?

New drug to prevent breast cancer recurrence shows promise

June 1, 2014
A new treatment option is more effective than tamoxifen at preventing a return of breast cancer in young women, according to the results of two international trials released Sunday.

Tamoxifen-resistant breast cancer reversed when drug paired with anti-malaria agent

June 13, 2014
The inexpensive anti-malarial drug hydroxychloroquine (HCQ) reverses resistance to tamoxifen, a widely used breast cancer drug, in mice.

Men develop breast cancer, too

July 8, 2014
(HealthDay)—While rare, breast cancer does occur in men and is often diagnosed at a later age and stage than in women, experts say.

Genes identify breast cancer risk and may aid prevention

March 19, 2013
A newly identified set of genes may predict which women are at high risk for getting breast cancer that is sensitive to estrogen and, therefore, would be helped by taking drugs to prevent it, reports a new Northwestern Medicine ...

Recommended for you

Cell cycle-blocking drugs can shrink tumors by enlisting immune system in attack on cancer

August 16, 2017
In the brief time that drugs known as CDK4/6 inhibitors have been approved for the treatment of metastatic breast cancer, doctors have made a startling observation: in certain patients, the drugs—designed to halt cancer ...

Toxic formaldehyde is produced inside our own cells, scientists discover

August 16, 2017
New research has revealed that some of the toxin formaldehyde in our bodies does not come from our environment - it is a by-product of an essential reaction inside our own cells. This could provide new targets for developing ...

Researchers find 'switch' that turns on immune cells' tumor-killing ability

August 16, 2017
Molecular biologists led by Leonid Pobezinsky and his wife and research collaborator Elena Pobezinskaya at the University of Massachusetts Amherst have published results that for the first time show how a microRNA molecule ...

Popular immunotherapy target turns out to have a surprising buddy

August 16, 2017
The majority of current cancer immunotherapies focus on PD-L1. This well studied protein turns out to be controlled by a partner, CMTM6, a previously unexplored molecule that is now suddenly also a potential therapeutic target. ...

A metabolic treatment for pancreatic cancer?

August 15, 2017
Pancreatic cancer is now the third leading cause of cancer mortality. Its incidence is increasing in parallel with the population increase in obesity, and its five-year survival rate still hovers at just 8 to 9 percent. Research ...

Skewing the aim of targeted cancer therapies

August 15, 2017
Headlines, of late, have touted the successes of targeted gene-based cancer therapies, such as immunotherapies, but, unfortunately, also their failures.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.