Update From the Medical Journals: March 2012
March 30, 2012
By Mary Pickett, M.D.
What's the latest news in the medical journals this month? Find out what your doctor is reading.
With new recommendations, many women can now stretch the time between Pap tests to every five years. In an incredible show of unity, the American Cancer Society (ACS), the U.S. Preventative Services Task Force (USPSTF), the American Society for Colposcopy and Cervical Pathology (ACCP) and the American Society for Clinical Pathology (ASCP) have all agreed on new screening recommendations. Each group published the guidelines separately (with minor differences in wording or emphasis) but they generally agree.
These groups represent four out of five of the expert groups that advise women about Pap tests. (The other expert group, the American College of Obstetrics and Gynecology (ACOG), is reviewing this new guideline. It is likely that the ACOG will accept the same recommendations. Members of ACOG were present at the committee meetings, and ACOG has made a statement about how helpful it can be for patients if expert groups all agree.)
The best timing and frequency for cancer screening tests balances the benefits, hassles and risks of testing. Our goal should be to use screening tests often enough to catch every or almost every cancer, but not so often that we put women through false alarms, extra exams, biopsies that are not necessary and unnecessary treatments. Treatments for abnormalities that are found on a Pap test can result in a slightly higher risk for pregnancy complications, such as pre-term labor and early (premature) delivery.
In the case of Pap tests, we can safely change to less frequent testing. We have more than a half century of data on the use of the test. We also have modernized techniques that improve the ability of the Pap test to screen for cancer. Now we can check for HPV particles in a Pap test. Changes on the cervix usually occur after infection with the human papillomavirus (HPV).
The new recommendations tell doctors when they should only check your Pap for abnormal cells (a microscope test called "cytology") and when they should also check for virus particles (a chemical test called "HPV testing"). When Pap tests are checked for both cytology and HPV, this is called "co-testing."
Women younger than age 21: You do not need a Pap test.
Women 21-29: Have a Pap test every 3 years. Your doctor should check cytology only and should not do HPV testing as long as the cells are normal. Women up to age 26 should receive the HPV vaccine series for added protection.
Women 30-65: Have a Pap test every 5 years. Your doctor should do "co-testing." If your most recent test was done without HPV testing, have a Pap test in 3 years.
Women older than 65: Stop having Pap tests if you have had either 3 normal Pap tests or 2 normal Paps with "co-testing" between age 55 and your current age.
Here are some special situations:
The initial findings from a study about organ transplants were released March 7, before the study was fully completed. The journal Science Translational Medicine1 published this research early because the study might end the need for anti-rejection drugs in the years after transplant surgery.
These strong medicines suppress the immune system. But you need a healthy immune system to fight infection and cancer. It would be ideal if immune-suppressant drugs weren't needed after transplants. People who have received their donated organ from a twin or very close relative don't need the drugs. The immune system does not see the organ as foreign.
An exciting technique called "chimerism" might prevent the need for taking immune-suppressant drugs forever after a transplant. Cells from the kidney donor's immune system are transplanted along with the organ. Before the transplant, doctors give the patient mild doses of radiation and chemotherapy. This makes the patient's immune system less active. The new immune cells along with the transplanted organ must be introduced while the immune system is not at its most active.
Because the donor's immune cells are mixed with the patient's own immune cells, the body seems to accept the transplanted tissue as if it had always been there.
People in the study received organs donated by strangers. There was a high chance the organs would be rejected without use of this new technique.
Five of the eight kidney transplant patients from the study now do not need any immune system drugs. Two more patients are able to take only one drug. These are extraordinarily successful results for such a new technique.
More than 25,000 transplants are done each year. Transplants with chimerism may be a way to provide what doctors are calling "transplant tolerance." If this technique seems safe and successful after more experience, it is likely to become the standard of care for transplant surgery.
Mary Pickett, M.D. is an Associate professor at Oregon Health & Science University where she is a primary care doctor for adults. She supervises and educates residents in the field of Internal Medicine, for outpatient and hospital care. She is a Lecturer for Harvard Medical School and a Senior Medical Editor for Harvard Health Publications.
1. J. Leventhal, et al. "Chimerism and tolerance without GVHD or engraftment syndrome in HLA-mismatched combined kidney and hematopoietic stem cell transplantation." Science Translational Medicine. 2012; Vol 4: 124-128.