September 1st, 2009 
The number of women diagnosed with breast cancer during pregnancy or soon after giving birth has more than doubled since the 1960s, and researchers say cases will continue to rise as women have children later in life.
The incidence of pregnancy-associated breast cancer rose from 16 in every 100,000 deliveries to 37.4 per 100,000 deliveries between 1963 and 2002, a study has found.
Breast cancer was under-diagnosed in pregnant and breastfeeding women because they and their doctors assumed breast firmness or lumps were a normal part of childbearing, said the chief executive of the National Breast and Ovarian Cancer Centre, Helen Zorbas.
She urged health professionals to assess all women the same way, regardless of pregnancy. ”While most breast changes won’t be cancer, early detection is vital for improving survival.”
Although pregnancy does not cause breast cancer, hormonal changes can accelerate its growth and tumours in pregnant women are often larger and more advanced by the time they are detected than those in women who are not pregnant.
The disease poses a dilemma for patients and their doctors. Pregnant women can have surgery but not radiotherapy. And chemotherapy is allowed only after the first trimester.
The study, published in the journal Obstetrics & Gynecology, reviewed more than 4.1 million deliveries in Sweden between 1963 and 2002.
The Karolinska Institute in Stockholm found the largest proportion of pregnancy-related breast cancers was among 25- to 29-year-olds.
But because the breast cancer risk rose with age and the average age of mothers had increased to about 30, its incidence during pregnancy was likely to increase, the institute said.
Related
- Pregnant women with breast cancer face good odds of recovery
Pregnant women who develop breast cancer do not have worse odds of death or of cancer returning than other young breast cancer patients, a recent study has found.
The study is one of the largest to look at whether breast cancer hits pregnant and recently pregnant women harder than other women. It contradicts some smaller, earlier studies that suggested maternity made things worse.
“If we can get them early, we can treat them aggressively and have good and promising outcomes for both woman and child,” said the study’s lead author, Dr. Beth Beadle of the University of Texas M.D. Anderson Cancer Center.
Frightening for any woman, a breast cancer diagnosis is particularly terrifying for a pregnant woman. It presents complicated decisions about how to treat the mother and not harm the fetus. Some doctors recommend abortion so they can focus on treating the mother.
In the new study, published earlier this year in the journal Cancer, researchers analyzed data from 652 women ages 35 and younger who were treated for breast cancer at M.D. Anderson from 1973 through 2006.
The study group included 104 women with pregnancy-associated cancers —- 51 who had breast cancer during pregnancy, and 53 who developed the illness within a year after.
The rates of cancer recurrence, cancer spread and survival were about the same for the women with pregnancy-associated breast cancers as they were for the other women, the researchers found. The researchers calculated the rates for 10 years after the cancer diagnosis.
The women who were pregnant had tumors at a more advanced stage, probably because women and their doctors may have discounted breast changes, attributing them to breast feeding or pregnancy, the researchers believe.
Generally, breast cancers are more aggressive in younger women, and survival rates are significantly lower. While age may be a factor, it’s not clear that pregnancy is: There was no evidence in the new study that tumors were faster growing in the pregnant women, said Beadle, a radiation oncologist.
Radiation —- dangerous to a fetus —- is commonly used in mammography and breast cancer treatment. But ultrasound can be used to look for breast tumors instead. And surgery and certain kinds of chemotherapy can treat the cancer without poisoning the womb.
However, it remains a complicated medical situation that can depend on the severity of the cancer and how far into the pregnancy the mother is, said Dr. Ruth O’Regan, an associate professor at Emory University’s Winship Cancer Institute in Atlanta.
- Pregnancy Safe For Breast Cancer Survivors
Women who survive breast cancer and have children afterwards don’t appear to be at any higher risk of dying from cancer, a new study says.
Doctors have long worried pregnancy might spark hormonal changes in breast cancer survivors that could spur the disease’s return, and many breast cancer patients are counseled against getting pregnant after they recover.
In research presented Friday at a European breast cancer conference in Barcelona, experts said pregnancy in women who have been treated for breast cancer is safe and does not seem to be linked with the disease’s recurrence.
Among women in the general population, those who have early and multiple pregnancies have a lower risk of getting breast cancer than women who don’t.
Dr. Hatem Azim of the Institute Jules Bordet in Belgium and colleagues analyzed results from 14 previous trials that followed more than 1,400 pregnant women with a history of breast cancer. Those women became pregnant several months to several years after finishing treatment. Azim and colleagues compared those women to more than 18,000 women who had had breast cancer and were not pregnant.
Azim and colleagues found that the women who got pregnant had a 42 percent lower risk of dying compared with breast cancer survivors who did not get pregnant. He said part of that benefit might be due to the fact that women who were naturally healthier were those that later had children.
But in some studies, women with breast cancer who became pregnant were compared to women who remained free of the disease, i.e. the healthiest of the breast cancer survivors.
“For many years, pregnancy was considered a risk for women who had breast cancer,” said Maria Leadbeater, a cancer expert at Breast Cancer Care, a British charity. “But this study seems to show the risk is not an issue once you’ve been treated,” she said. Leadbeater was not connected to Azim’s study.
Leadbeater said the advice for patients might vary depending on the type of breast cancer they’ve had and how they responded to treatment. Women who need hormone therapy for breast cancer typically need to be on it for five years — during which time doctors recommend against getting pregnant.
Leadbeater and others said women should try to wait until two years after their diagnosis to try for a baby, since that is thought to be the riskiest time for a relapse.
Azim, who led the study, hypothesized that the relationship between hormones and breast cancer might be more complicated than doctors initially thought. Estrogen is known to trigger breast cancer and women typically have more estrogen when they’re pregnant. But very high doses of the hormone can also kill cancer cells, Azim said.
Other hormones that are elevated in pregnancy, like the one for breast-feeding, have been proven to protect against breast cancer. “What we are seeing is only the tip of the iceberg,” Azim said. “It’s too simple to say that pregnancy stimulates hormones and that’s bad for breast cancer.”
- Pregnant Mother’s Cancer Can Pass to Fetus
Over the past century doctors have suspected that cancers can spread from a pregnant woman to her fetus, but a genetically confirmed case reported this week from Japan suggests the phenomenon is real.
Mother-to-fetus transmission still likely rare, experts say, since the placenta acts as a barrier to cells from the mother, and the fetal immune system would reject and destroy cancer cells.
“Some 30 times reported in the past, mother and infant have appeared to share the same cancer, usually leukemia or melanoma,” noted lead researcher Dr. Shuki Mizutani of the department of pediatrics at Tokyo Medical and Dental University.
“The suspicion has been that the cancer may have developed in the pregnant woman but then spread to the baby in the womb. There has however been no clear genetic evidence to support this interpretation, which was shown unambiguously by our study for the first time,” Mizutani said.
The report is published in the Oct. 12 online edition of the Proceedings of the National Academy of Sciences.
For the report, Mizutani’s team studied the case of a 28 year-old Japanese woman who developed leukemia after giving birth. At 11 months, her baby girl developed the same type of leukemia.
A genetic analysis found that both mother and daughter had an identical match for a mutated cancer gene called BCR-ABL1. However, this mutation had not been inherited in the child’s DNA, which suggested that the cancer cells had developed independently in both the mother and her fetus.
Using genetic “fingerprinting,” the researchers found that the cancer cells had developed in the mother and were transmitted to her baby in utero.
In addition, Mizutani’s team found that these cancer cells had destroyed an area of the infant’s DNA that is normally able to distinguish between the infant’s and mother’s cells.
Based on this finding, the researchers believe cancer cells from the mother crossed the placenta and succeeded in implanting themselves into the fetus, unrecognized by the developing immune system.
The finding isn’t all that surprising, one expert said.
“People have believed that this has been the case for some time. This is really crossing the Ts dotting the Is and showing that that’s really the case,” said William H. Chambers, scientific program director at the American Cancer Society.
He stressed that this type of transmission remains a rare occurrence. “I don’t think people are going to decide that there are a whole lot more of these cancers,” he said. “It’s pretty rare that someone is going to find out they have a disease like this during or after pregnancy.”
Mizutani agreed, but said precautions can still be taken.
“Malignant tumors are estimated to develop in one case of 1,000 pregnancies,” Mizutani said. “The frequency of developing leukemia is estimated to be 1 in 75,000 to 100,000 pregnancies. Thus, although it might be rare, babies born in pregnant women who develop cancer during pregnancy should be placed under careful observation.”
- Prompt treatment beneficial for pregnant and postpartum women with H1N1
Delayed treatment of suspected influenza A (H1N1) illness among pregnant women may result in a four-fold risk of intensive care admission or death, according to results of a recent study.
Regardless of rapid antigen test results, prompt evaluation and antiviral treatment should be considered for pregnant or postpartum women displaying influenza A (H1N1)-like symptoms, according to researchers from the California Department of Public Health.
The study was a review of records for women of reproductive age who had been hospitalized or died from influenza A (H1N1) between April 23 and August 11, 2009.
The study involved 94 pregnant women, 137 non-pregnant women and 8 postpartum women who had delivered <2 weeks prior. False negative results for rapid antigen tests were observed in 38% of patients.
Among 94 pregnant women, 95% were in the second or third trimester. Risk factors for complications from influenza other than pregnancy were observed in 32 of 93 (34%) of those pregnant women.
Early antiviral treatment was defined as treatment <2 days after the onset of symptoms. Pregnant women treated later than this had an RR of 4.3 for admission to an ICU or death.
Intensive care was required for 18 pregnant women and four postpartum women (total, 22 of 102 [22%]). There were eight deaths (8%).
Of six deliveries which took place in the ICU, four were emergency cesarean deliveries.
The specific mortality ratio associated with influenza A (H1N1), which the researchers defined as the number of maternal deaths per 100,000, was 4.3.
- Pregnant Women With MS Have Good Outcomes
Good news for women with multiple sclerosis (MS) who are pregnant or thinking about becoming pregnant. A study published Wednesday shows that while women with MS have a somewhat heightened risk of certain pregnancy complications, by and large, their pregnancies are as healthy as other women’s.
Using a national database on nearly 19 million deliveries in the U.S., researchers found that women with MS had marginally higher risks of cesarean delivery and intrauterine growth restriction — where a newborn’s weight is below the 10th percentile for his or her gestational age.
Among more than 10,000 women with MS who gave birth between 2003 and 2006, 42 percent had a C-section, compared with roughly 33 percent of women overall. Meanwhile, intrauterine growth restriction was seen in almost 3 percent, versus 2 percent of other women. Still, the overall findings, published in the medical journal Neurology, are being seen as good news for women with MS — a disorder that is more prevalent among women of childbearing age than any other group.
MS is believed to arise from an abnormal immune system attack on the body’s own myelin, a protective sheath surrounding nerve fibers in the brain and spine. This leads to symptoms such as muscle weakness, numbness, vision problems and difficulty with coordination and balance.
Years ago, women with MS were advised to avoid pregnancy, out of concern that it could exacerbate the disease. But studies in recent decades have shown that the opposite is true; many women see a remission in their symptoms during pregnancy — possibly because immune system activity naturally declines and levels of anti-inflammatory corticosteroids naturally rise during pregnancy.
The current study included information on 10,055 pregnant women with MS, as well as 4,730 with epilepsy and 187,239 with diabetes — two disorders already associated with higher risks of certain pregnancy complications.
Overall, women with either MS or epilepsy had elevated risks of C-section delivery and intrauterine growth restriction compared with U.S. women overall. They did, however, generally fare better than women with diabetes, who had higher rates of additional complications, like high blood pressure and premature rupture of the sac surrounding the fetus.
Women who are planning on becoming pregnant also need to talk with their doctors about whether they should stop taking any of their MS medications. It is not known whether the so-called disease-modifying drugs often used for MS are safe during pregnancy, and research suggests that at least one — beta-interferon — may be associated with miscarriage.
Chakravarty noted that the drug methotrexate, sometimes used for MS, is known to cause birth defects.
