Past Cancer Therapy Could Pose Risk to Expectant Moms
Physicians should carefully monitor the pregnancies and babies of women who undergo egg retrieval and in vitro fertilization after cancer therapy, says an international team of fertility experts.
Their concern arises from studies in mice, reported in the April issue of the journal Human Reproduction, showing that female mice treated with the cancer drug cyclophosphamide have fewer successful pregnancies, a higher spontaneous-abortion rate and a higher incidence of malformation among their fetuses. The risk is greatest immediately after exposure to the drug and declines to normal after 12 weeks.
The team--including Dr. Dror Meirow at the Rabin Medical Centre in Israel, Dr. David Nugent at the University of Leeds in England and Dr. Roger Gosden at the Royal Victoria Hospital in Montreal--emphasized that there is not yet any evidence of a similar effect in humans but cautioned women not to get pregnant soon after chemotherapy with cyclophosphamide and other so-called alkylating agents. They also urged doctors to be alert to the potential for harm and to monitor patients closely.
20-Year-Old Drug May Treat Batten Disease
A drug that has been around for more than two decades may provide the first effective treatment for Batten disease, a rare genetic disorder that robs its victims of their eyesight and mental abilities before claiming their lives in their teens.
Batten disease strikes one in every 12,500 children worldwide and is caused by the buildup of lipopigments in the body, killing cells and impairing the function of various organs. Victims lack the enzyme necessary to break the lipopigments down into lipids and proteins, allowing them to accumulate and kill tissues.
Researchers from the National Institute of Child Health and Human Development report in the April issue of Nature Medicine that the drug phosphocysteamine breaks down the lipopigments, in effect taking the place of the naturally occurring enzyme. Phosphocysteamine has been approved by the Food and Drug Administration and used for at least 20 years in treating another rare genetic disorder called cystinosis, which causes blindness, kidney failure and death by age 9. The team is now seeking patients for testing.
Norplant Does Well in Safety Study
The implantable contraceptive Norplant is as safe and effective as sterilization and intrauterine devices, according to a major new study conducted by the World Health Organization and the Population Council. The implant contains the hormone levonorgestrel, which is released slowly over five years, preventing pregnancy.
The study monitored 7,977 Norplant users, 6,625 IUD users and 1,419 sterilized women in eight developing countries. The women were enrolled between 1987 and 1991 and followed for five years.
The team reported in the April issue of Obstetrics & Gynecology that there was no increased risk of cancer, cardiovascular disease or other serious illnesses among women who used Norplant. The incidence of hypertension was slightly higher in those who used Norplant, and there was a slight increase in gallbladder disease among women in Chile and China who used it. But the risk of acute pelvic infection, low abdominal pain and dysmenorrhea were lower in Norplant users than in those using IUDs or who were sterilized. Overall, about one in every 100 women in the study became pregnant, most of them after stopping use of contraceptives.
Cancer Treatment Also a Cancer Risk
The powerful drugs and radiation that have been so successful in treating childhood cancer have the unfortunate disadvantage of increasing cancer risk later in life, according to the largest follow-up study yet undertaken.
Dr. Joseph Neglia reported last week at a New Orleans meeting of the American Assn. for Cancer Research on a study of 13,581 children and adolescents who had survived at least five years after treatment for leukemia and other malignancies.
In all, 298 of the patients got new cancers an average of 12 years after their first tumors. The most common new malignancies were breast cancer, thyroid cancer and brain cancer. Overall, the survivors had a 3% risk of developing a new cancer over the 20 years following their successful therapy, six times the rate for those who had not suffered childhood cancer. Both chemotherapy and radiation damage DNA, which can lead to tumor formation.
Between 8,000 and 10,000 new cases of childhood cancer are diagnosed in the United States each year, with about 70% of them being cured. About one in every 1,000 Americans in their 20s is a cancer survivor.
Antidepresssant and Interferon a Good Team
Interferon is an effective drug for treating patients with certain cancers and hepatitis, but it causes severe depression in some, interfering with treatment. A new study indicates that pre-treating patients with the antidepressant paroxetine can sharply reduce that side effect.
Dr. Dominique Musselman and his colleagues at Emory University School of Medicine in Atlanta studied 40 patients with malignant skin cancer who were treated with interferon alpha-2b. Half began taking paroxetine (trade name Paxil) two weeks before the interferon treatment, and half received a placebo.
The team reported in the March 29 issue of the New England Journal of Medicine https://(www.nejm.com) that 11% of the paroxetine patients were diagnosed with severe depression, compared with 45% of the placebo group. The depression became so severe that 35% of the placebo group had to stop taking interferon, compared with only 5% of those receiving the antidepressant.
Fat-Burner Might Be More Than Just a Dream
Food supplements that purport to burn off fat and calories while you sleep do not work, but new research out of Baylor College of Medicine suggests that such a drug could be on the horizon.
Dr. Salih Wakil and his colleagues reported in the March 30 issue of Science that they had identified an enzyme that regulates the body’s ability to burn fat and that could lead to new ways to treat obesity and diabetes.
Wakil produced genetically engineered mice that were deficient in an enzyme called acetyl-CoA carboxylase 2. The mice were able to eat as much as 40% more than normal mice but still weighed 10% to 15% less. The genetically engineered mice “seem very happy, live and breed well,” Wakil said. The difference is that they ate more, weighed less and accumulated less fat than normal animals. The team speculated that drugs that interfere with activity of the enzyme could be used to stimulate weight loss.
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Medical writer Thomas H. Maugh II can be reached at thomas.maugh@latimes.com. Capsules runs every Monday.
