News in brief - Nov. 28, 2005

Ovarian cancer screening tests not recommended for widespread use - Syphilis up, gonorrhea down - Narrow-band antibiotic may be effective for some forms of IBS - Children can outgrow tree nut allergy

Ovarian cancer screening tests not recommended for widespread use

Currently available screening methods for ovarian cancer, such as transvaginal ultrasound or TVU, and testing for the protein biomarker CA-125, can detect the cancer either alone or in combination. But the tests also produce many false-positive results causing needless surgery, according to a new National Cancer Institute study.

Of the 28,816 healthy women who underwent the initial screening, 1,338 had an abnormal ultrasound exam and 402 had an abnormal blood test. Thirty-four women had abnormal results in both screening tests. Among the nearly 1,400 women with abnormal test results, 29 tumors were detected, 20 of which were invasive cancers.

Women who had an abnormal test result underwent a variety of diagnostic procedures to determine whether cancer was present. Of the 570 who had a surgical procedure, 541 were found not to have cancer.

The findings are the first published ovarian cancer screening results from NCI's ongoing multicenter Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial. They appear in the November American Journal of Obstetrics and Gynecology.

"Ovarian cancer is a disease that is often fatal, and both patients and physicians are anxious to find ways to detect it at an earlier, more curable stage," said lead author Saundra Buys, MD, an oncologist at the University of Utah's Huntsman Cancer Institute. "However, the results from the initial year of screening show that TVU and CA-125 cannot currently be recommended for widespread use in the general population."

Syphilis up, gonorrhea down

The rate of syphilis increased for the fourth year in a row, but gonorrhea rates hit a new low last year. The chlamydial infection rate also inched upward, but this is most likely due to increased testing, according to the report, "Sexually Transmitted Disease Surveillance 2004," issued this month by the Centers for Disease Control and Prevention.

According to the CDC's data, syphilis went up 8% from 2003 to 2004, being primarily driven by a nearly 12% bump in the rate in men. The rate among women was unchanged.

Chlamydia has also increased by nearly 6%.

"Reported cases are just the tip of the iceberg," said John Douglas Jr., MD, director of the CDC's STD prevention programs. "Health care providers urgently need to step up screening."

Gonorrhea rates fell 1.5%, but public health officials are concerned because the bacteria are increasingly resistant to first-line antibiotics.

Narrow-band antibiotic may be effective for some forms of IBS

An antibiotic that only affects bacteria in the gut may be beneficial for some patients with irritable bowel syndrome, according to a study presented at the American College of Gastroenterology's annual meeting in November.

Patients were randomized to receive either the antibiotic rifaximin or a placebo pill every day for a week. Approximately 37% of those who received the drug had significant improvement, while only 16% of those who received placebo did. The most significant impact was on bloating and diarrhea, although no impact was found on constipation.

Researchers suggest that this drug may be able to address the small intestine bacterial overgrowth believed to play a part in the condition.

"These results clearly show that antibiotics offer a new treatment approach," said Mark Pimentel, MD, lead author and director of the gastrointestinal motility program at Cedars-Sinai Medical Center in Los Angeles.

Children can outgrow tree nut allergy

Nine percent of children allergic to almonds, pecans, cashews and other tree nuts outgrow their allergies over time, even if they have had a severe reaction, according to researchers at Johns Hopkins Children's Center in Baltimore, Md.

The study, published in the November Journal of Allergy and Clinical Immunology, also found that clinicians can use blood levels of tree nut antibody as an accurate guideline in estimating the likelihood a child has outgrown the allergy.

"What's crystal clear is that children with these allergies should be regularly re-evaluated," said lead author Robert Wood, MD, director of the Division of Allergy and Immunology at Johns Hopkins Children's Center.

In the United States, an estimated 1% to 2% of the population is allergic to tree nuts, peanuts or both. The researchers had previously reported that as many as 20% of children outgrow peanut allergy and recommended that allergists periodically retest their patients. The current study explored whether the same held true for tree nuts.

Dr. Wood and colleagues evaluated 278 children ages 3 to 21 years old with a known allergy to tree nuts.