“Cancer Screening: The Clash of Medical Science and Intuition” leads off 2008 “Medicine for the Public” Series at NIH Clinical Center

EPISODE #6
Uploaded:  November 17, 2008
Running Time:  4:28

SCHMALFELDT: From the National Institutes of Health in Bethesda, Maryland, this is CLINICAL CENTER RADIO.

The notion that early detection of cancer saves lives seems like a simple and obvious truth.  However, many generally-accepted cancer-screening procedures have yet to be proven effective.  And all have associated risks that are often overlooked by patients and their health care providers.  So, what does it mean for a screening test to be considered effective?  And how can you tell the difference between what is known about cancer screening and what makes intuitive sense?  Those are some of the questions to be explored at the opening lecture in the 2008 “Medicine for the Public” series, November 25 at 7 pm in the NIH Clinical Center’s Lipsett Amphitheater.  Dr. Barnett S. Kramer, associate director for disease prevention in the Office of Medical Applications of Research, Office of Disease Prevention, in the Office of the Director at the NIH, and co-author of the book “Cancer Screening: Theory and Practice” will present the topic.  Dr. Kramer said the take-home message for people who hear his lecture will be, “an informed patient is the best patient.”

KRAMER:  I think they’ll leave knowing that there are some screening tests that are useful out there, that are proven to be of benefit in the best form of study, which is a randomized, controlled trial.  They will also leave knowing that some screening tests that are in common use have not even been put to a definitive trial, and so we’re not certain whether they’re of net benefit or net harm.  And I hope they’ll leave being able to evaluate for themselves and ask the right questions about whether any new screening test they hear about is proven, and they’ll be able to evaluate the messages that are sometimes overenthusiastic in the newspapers and magazines.

SCHMALFELDT: Dr. Kramer said that even with the advanced cancer screening techniques already available, some cancers still get missed.

KRAMER:  We, presumably, do miss cancers even when we use screening tests because even the best of our screening tests available today aren’t sensitive enough to pick up every cancer that’s there, so that in any screening study or any screening experience you can expect to see what are called “interval cancers” – and that is cancers that are diagnosed because of clinical symptoms in between screening tests.

SCHMALFELDT: He will also discuss some of the studies currently underway at the NIH to improve the efficiency and effectiveness of cancer screening.

KRAMER:  Screening is a very important part of all of medicine, but in particular an important part of cancer management and cancer prevention.  For that reason, the National Cancer Institute is funding two very large cancer screening trials.  There was one that was launched in the early 1990s that’s known as the PLCO, or the screening trial for prostate, lung, colorectal and ovarian cancer.  And then there was another one launched in this century – the NLST, or the National Lung Screening Trial, specifically aimed at lung cancer and it is comparing spiral CT of the lung with chest X-ray.

SCHMALFELDT: Dr. Kramer said since the target population for any screening test is “healthy people” – that is, people without current symptoms of cancer -- cancer screening warrants informed decision making on the part of the patient and the health care provider.  “Medicine for the Public” is a series of lectures on disease-related topics by NIH scientists, sponsored by the NIH Clinical Center.  Since 1977, the series has provided the public with the latest information on medical research.  For more information, including info on all four “Medicine for the Public” presentations, log on to  http://clinicalcenter.nih.gov.  From America's Clinical Research Hospital, this has been Episode One of CLINICAL CENTER RADIO.  In Bethesda, Maryland, I'm Bill Schmalfeldt at the National Institutes of Health, an agency of the United States Department of Health and Human Services. 

Back to Clinical Center Radio