Peter Shields, MD
Biography

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Lung cancer is the No. 1 cause of cancer deaths for men and women in America. In light of the recent death of news anchor Peter Jennings and the announcement by Christopher Reeve's widow, Dana, WebMD Live invited Peter Shields, MD, from the Lombardi Comprehensive Cancer Center at Georgetown University to answer your questions lung cancer. He was our guest on Aug. 18, 2005.

If you have questions about your health, you should consult your personal physician. This event is meant for informational purposes only.

MODERATOR:
Welcome to WebMD Live. Our guest today is Peter Shields, MD, from the Lombardi Comprehensive Cancer Center at Georgetown University. He is here to answer questions about lung cancer.

Welcome, Dr. Shields. The death of Peter Jennings and the announcement of Dana Reeve's diagnosis has taken a lot of people by surprise, but it really shouldn't.

SHIELDS:
Unfortunately, lung cancer is a pretty common disease; it's the No. 1 cause of death from cancer. There's a whole lot of current smokers out there and several-fold more ex-smokers, all at risk for lung cancer. By and far it is the biggest risk factor. Before smoking lung cancer was a rare disease.

SHIELDS:
Your risk goes down immediately after quitting. What a lot of people don't understand is your risk can never go back to as if you were never a smoker.

There is no question that quitting substantially reduces your risk, compared to continued smoking, and at every age it is a real benefit to quit smoking. But unfortunately, that risk does not go down to as if you never smoked.

MEMBER QUESTION:
How does lung cancer first manifest itself?

SHIELDS:
The way lung cancer can present itself includes:

• A cough
• Shortness of breath
• Weakness and weight loss
• Sometimes chest pain

Lung cancer remains silent for a long period, and that's when it can be small enough to do something about.

"It's not recommended to have a CAT scan for lung cancer screening, even for smokers."

MEMBER QUESTION:
I am having problems with a nagging cough especially at night, also joint pain. I know X-rays do not show lung cancer until it's too late. Should I have a CAT scan or MRI?

SHIELDS:
Of course I can't give specific medical advice, but you do have risk factors for lung cancer and obviously with a persistent cough you should have quality medical care.

Having said that, at the current time it's not recommended to have a CAT scan for lung cancer screening, even for smokers. But if you're having symptoms related to the lung, then a physician might consider a CAT scan is indicated.

MEMBER QUESTION:
Do chest X-rays detect lung cancer?

SHIELDS:
This is complicated for most people to understand. CAT scans are more sensitive than X-rays, but they also pick up many things that are suggestive of cancer that turn out not to be cancer.

At the current time, we do not know if we are hurting people, because of false positives, more than helping them. There's a large national clinical trial of over 60,000 smokers and ex-smokers so we may know more in a few years.

But at the current time, most of the major organizations who are knowledgeable about cancer screening do not recommend X-rays or CAT scans for smokers.

MODERATOR:
What do they recommend for screening?

SHIELDS:
The clearest recommendation is to stop smoking. That's the only known way to reduce one's risk of lung cancer.

In terms of screening, there is unfortunately no recommendation because we're afraid we're going to be hurting people more than helping them; a workup for a lung cancer lesion seen on X-ray can be substantial. In general we don't recommend screening.

The opinions expressed herein are the guests' alone and have not been reviewed by a WebMD physician.