Ductal carcinoma in situ is a noninvasive form of breast cancer. Although the condition is not life-threatening in itself, it may increase the chances of developing an invasive form of breast cancer later in life. However, a new study suggests that women who have been treated for ductal carcinoma in situ continue to live as long as other women.
According to the American Cancer Society, ductal carcinoma in situ (DCIS) accounts for approximately 1 in 5 newly diagnosed breast cancers.
DCIS is found in the breast's milk ducts and is deemed "noninvasive" because it does not spread to the rest of the body.
However, there is a risk that DCIS evolves into an invasive form of breast cancer - currently estimated at under 30 percent - which is why the condition is typically treated with surgery or a combination of surgery and radiation therapy.
To eat soy or not: That's the question many U.S. women have been asking. Tofu, miso paste and other soybean-based foods are high-quality sources of protein that are low in calories and saturated fat. And studies have shown that they can help prevent cancer.
Yet many doctors recommend that women who have, or are at risk of developing, a common form of breast cancer called estrogen-receptor-positive breast cancer avoid eating soybean-based foods because they contain compounds called isoflavones. Some studies suggest that isoflavones can mimic the hormone estrogen and encourage tumor growth.
Now, in an animal study, researchers at the Georgetown Lombardi Comprehensive Cancer Center in Washington, D.C., have uncovered a possible reason for the apparent Jekyll-and-Hyde nature of soy — how it can both prevent cancer and fuel its spread.
The researchers found that rats that were given soybean isoflavones to eat throughout their lives — in particular, one type of soybean isoflavone called genistein — had improved immunity against cancer. But rats that weren't given the isoflavone until after developing breast cancer didn't have that same immune response to kill cancer cells. Instead, these rats had higher rates of cancer growth and higher rates of recurrence after their tumors were removed.
Mayo Clinic researchers have identified a potential treatment for breast cancer metastasis that, if corroborated, could prove beneficial in many other cancer treatments.
That groundbreaking announcement was made in a paper published Dec. 9 in Nature Communications, a medical journal. However, the study's senior author Dr. Zhenkun Lou cautioned that more research is necessary.
The new Mayo study identifies a possible way to prevent the spread of cancer, called metastasis, typically through the lymph system or bloodstream. Perhaps more significantly, the class of drugs tested by Dr. Lou and his team are already approved by the U.S. Food and Drug Administration.
The paper suggests that a key drug target, called CDK 4/6, regulates a cancer metastasis protein, dubbed SNAIL. Dr. Lou's research shows that drugs that inhibit CDK 4/6 could prevent the spread of triple-negative breast cancer.
"Metastasis is a hallmark of cancer and a leading cause of cancer death," Dr. Lou said. "Despite great progress in cancer therapy, the prevention of cancer metastasis is still an unfulfilled challenge."
2 millimeters is enough to guard against recurrences while reducing need for additional surgeries
New surgery guidelines for certain breast cancer patients could reduce both unnecessary surgeries and recurrence rates, three U.S. cancer groups say.
The guideline is for treatment of women with ductal carcinoma in situ (DCIS) who undergo breast-conserving surgery with whole breast radiation. DCIS is an early stage cancer
"The use of a 2-millimeter margin as the standard for an adequate margin in DCIS treated with whole breast radiation therapy is associated with low rates of recurrence of cancer in the breast and has the potential to decrease re-excision rates, improve cosmetic outcome and decrease health care costs," according to the guideline from the Society of Surgical Oncology, the American Society for Radiation Oncology and the American Society of Clinical Oncology.
"Margins more widely clear than 2 millimeters do not further reduce the rates of recurrence of cancer in the breast and their routine use is not supported by evidence," the guidelines stated.
Breast cancer is the most common form of cancer, affecting women worldwide. Although the survival rate is very high when the disease is discovered early, new research suggests that having a large social network might also affect a person's chances of survival.
Having more social ties may lead to higher survival rates, new study finds.
Breast cancer affects hundreds of thousands of women around the world each year. In the United States alone 246,660 women are estimated to receive a breast cancer diagnosis every year. That is 1 in every 8 women.
Around 40,000 American women die of breast cancer every year. However, breast cancer survival rates look encouraging, especially if the disease is detected early.
Since 1990, breast cancer survival rates have been increasing. Due to better screening practices, increased public awareness and early detection, and improved technology and treatments, mortality in women aged 50 and older has been declining significantly for the past 2 decades.
In the U.S. there are currently over 2.8 million breast cancer survivors.
The one-size-fits-all approach to early stage breast cancer creates a paradox: Millions of dollars are spent on unnecessary surgeries and radiation to treat women with low-risk 'in situ' lesions, an estimated 85% of which would never progress to invasive cancers. Meanwhile, the standard conservative treatment is insufficient for many early-stage tumors that have progressed past the in situ stage and fails to prevent their spread to distant sites in the body.
Now Whitehead Institute researchers have identified SMARCE1, a gene overexpressed in the subset of early-stage cancers that are likely to become aggressively invasive -- making it possible for the first time to distinguish poorly invasive tumors from those that will likely spread and metastasize. With such a biomarker, doctors could better tailor therapies designed to match the behavior of each patient's cancer.
The researchers found that 50 percent of the early-stage cancers with high SMARCE1 expression will metastasize at some point in the 10 to 15 years after their initial diagnosis. "Early-stage cancers are not all the same. Some are destined to go rogue and should be treated from the outset with this understanding in mind," says Whitehead Member Piyush Gupta, who is also an assistant professor of biology at MIT.
Breast cancer begins as anomalous cells that divide out of control, usually in the milk ducts. In almost all cases, a patient does not succumb to the initial cancer but to the secondary tumors after the cancer has spread.
A review of the latest scientific research on breast cancer shows that there is strong evidence that breast-feeding can reduce women's risk of premenopausal and postmenopausal breast cancers.
A report on the review, by the American Institute for Cancer Research (AICR) and the World Cancer Research Fund (WCRF), has been released this week to mark World Breastfeeding Week.
The report offers several possible explanations for how breast-feeding lowers breast cancer risk. One reason is that lactation delays when women start menstruating again after giving birth. This reduces lifetime exposure to hormones such as estrogen, which are linked to increased risk of breast cancer.
Another way in which breast-feeding may lower breast cancer risk is that, after lactation, the breast sheds a lot of tissue during which it may also get rid of cells with damaged DNA, which can give rise to cancer.
The report also suggests that lactation may change the expression of genes in breast cells in a way that exerts a "lasting impact" on the risk of cancer development.
'EXCLUSIVE BREAST-FEEDING FOR 6 MONTHS'
Breast cancer is a disease that develops when abnormal cells in the breast begin to multiply and form a tumor. Although men can also get breast cancer, the disease arises almost always in women.
In the United States, breast cancer is the most common cancer in women, not counting skin cancer.
In 2014, 236,968 women and 2,141 men living in the U.S. found out that they had breast cancer. In that year, 41,211 women and 465 men also died of the disease.
The new report reviewed 18 studies on lactation and breast-feeding. From the 13 that evaluated the effect of length of breast-feeding, the report finds that for every 5 months of breast-feeding duration, there is a 2 percent lower risk of breast cancer.
In line with other agencies such as the World Health Organization (WHO), the AICR recommend that babies are breast-fed exclusively for up to 6 months before introducing other foods. Not only does breast milk provide infants with essential nutrients, it also boosts their immune system and helps to protect them from infection and asthma.
A recent report from the Centers for Disease Prevention and Control (CDC) on U.S. breast-feeding practices suggests that while breast-feeding rates continue to rise, recommendations on how long to breast-feed for and when to introduce other foods are not being met.
The CDC report shows that among babies born in 2013, the vast majority (81.1 percent) started breast-feeding, suggesting that most mothers in the U.S. want to breast-feed and try to do so. But by the time they were 6 months old, only around half (51.8 percent) of the babies were still breast-feeding.
Obesity is a known risk factor for breast cancer, but precisely how does excess weight drive the disease? A new study has shed some light, revealing the process by which obesity increases the aggression of breast cancer cells.
By studying mouse and human breast cancer tissue, researchers discovered an increase in blood levels of specific cytokines — which are proteins secreted by immune cells — that reduce the activity of an enzyme called acetyl-CoA-carboxylase 1 (ACC1).
This process leads to a buildup of a fatty acid precursor called acetyl-CoA, which increases the metastatic ability of breast cancer cells — that is, their ability to spread to other parts of the body.
Obesity and breast cancer
Being overweight or obese is a well-established risk factor for breast cancer. In fact, after going through menopause, women who are obese are 20–40 percent more likely to develop breast cancer than women of a healthy weight.
Obesity has also been associated with an increased risk of breast cancer metastasis and reduced survival from the disease.
However, the exact mechanisms underling the link between between obesity and breast cancer have been unclear.
To find out more, Dr. Herzig and colleagues investigated the activity of the enzyme ACC1 in mouse-derived breast cancer cell lines, as well as in breast tissue taken from patients with metastatic breast cancer.
Previous studies have indicated that ACC1 — which plays a role in the synthesis of fatty acids — may be involved in cancer metastasis.
Obesity increases cytokine release
The analysis revealed that metastatic breast cancer cells have reduced ACC1 levels compared with healthy cells, especially among obese subjects.
The reduction in ACC1 leads to an accumulation of acetyl-CoA. The buildup of acetyl-CoA modifies transcription factors — or proteins that regulate gene expression — in a way that promotes breast cancer metastasis.
Further investigation revealed that obesity leads to an increase in the release of two cytokines, called leptin and transforming growth factor beta, into the bloodstream. These cytokines inhibit ACC1 in breast cancer cells.
The researchers then used an antibody to block a pathway associated with leptin release in human breast cancer cell lines, which, in turn, prevented ACC1 inhibition. They found that this prevented the cancer cells from metastasizing.
Based on their results, the researchers believe that they may have uncovered a potential new therapy for breast cancer.
In a recent study published in the Journal of Clinical Investigation, Mayo Clinic researchers identified that an FDA drug approved for myelodysplastic syndrome may be useful to treat triple-negative breast cancer, which is one of the most aggressive and lethal types of breast cancer.
In this study, Mayo investigators identified that the drug 5-aza-2'-deoxycytidine (decitabine) which is FDA approved for the treatment of certain hematological (blood) cancers, could significantly inhibit the growth of triple-negative breast cancers, and importantly this effect was also seen in tumors resistant to chemotherapy. This response was dependent on the presence of certain critical proteins called DNA methyl transferase proteins that are present in only a subset of triple negative breast cancers. This provides a way to identify which patients could benefit from this therapy.
"There is a great need to identify additional treatment options for triple-negative breast cancer, which is one of the most difficult to treat subtypes of breast cancer," says Mayo researcher Liewei Wang, M.D., Ph.D. "The study is a demonstration that we can take advantage of many existing FDA approved drugs to expand their usage by better understanding the mechanisms of how they work and applying them to other cancers."
This study was part of the ongoing work from the Breast Cancer Genome-Guided Therapy (BEAUTY) study, co-led by Matthew Goetz, M.D., a Mayo medical oncologist and Judy Boughey, M.D., a Mayo breast surgeon. The BEAUTY study generated patient derived xenografts (immortalizing breast tumor cells) from patients with breast cancer treated with chemotherapy.
"Patients whose tumor does not respond well to chemotherapy are known to be at significantly increased risk of recurrent breast cancer and death," says Dr. Boughey. "Therefore our focus is to identify new treatment options for these patients."
In the living xenografts from BEAUTY, Mayo investigators found that when DNA methyl transferase proteins were present, decitabine showed an effect in triple-negative breast cancer at a low therapeutic dose. The low doses would result in less toxicity and might allow the drug to be used for a longer time, all of which might help to achieve greater therapeutic efficacy.
According to Dr. Goetz, plans are underway to prospectively study the impact of decitabine in a prospective clinical trial, called BEAUTY2, which is focused on women with triple negative breast cancer that is resistant to chemotherapy.