O'Connell's team is still doing trials of the system and will not have a full study until 60 women have undergone imaging. But the results so far suggest the CT scan can detect more of a tumor than a mammogram can, O'Connell said. So far, the Cone Beam scanner has detected every tumor seen on a mammogram, she said.

"The mammogram is not 100 percent. It never was," O'Connell said in a telephone interview. "Mammograms in the best hands in the world will miss 15 percent of tumors."

They are difficult to read because the mammogram X-ray reduces a three-dimensional structure -- the breast -- to two dimensions.

WHITE ON WHITE

"You have the white thing -- the tumor -- superimposed on this other white stuff -- that's the healthy tissue," O'Connell said.

Women with "dense" breasts were always difficult to image, she said. A mammogram that does not show a tumor does not mean a woman with dense breasts is cancer-free. "All it means is that we can't see anything. It doesn't mean there is nothing there."

And mammograms can often show only part of a tumor -- what looks like a speck on a mammogram is often the core of a much larger tumor.

O'Connell believes the Cone Beam system will be popular if it is ever approved. It would be far more comfortable than getting a mammogram.

"You lie there. You hold still. It takes 10 seconds," said O'Connell, who was subject number 3 in the trial.

"You are lying on the table with the breast dependent," she said -- the breast is allowed to hang through a hole in the table. The scanner takes 300 shots from every angle.

"The computer does its magic and reconstructs what looks like a breast," O'Connell said.

While CT scans can deliver a hefty dose of radiation, this scanner does not, said O'Connell.

"This gives approximately the same dose as a mammogram," she said.

She believes the first target patients should be women at high risk of breast cancer, who can justify having a pricier screening.

"The insurance is not going to want to pay for a CT," O'Connell said. The average cost of a mammogram is $80, she said -- a CT can cost several hundred.

Breast cancer is the biggest cancer killer of women, after lung cancer, with 1.2 million cases globally -- 270,000 in the United States alone.

It kills 500,000 men and women every year globally -- 40,000 in the United States.

The university has licensed the technology to a Rochester, New York start-up company, Koning Corporation, to make, use and sell Cone Beam scanners.

Copyright © 2006 Reuters Limited. All rights reserved. Republication or redistribution of Reuters content, including by framing or similar means, is expressly prohibited without the prior written consent of Reuters. Reuters shall not be liable for any errors or delays in the content, or for any actions taken in reliance thereon. Reuters and the Reuters sphere logo are registered trademarks and trademarks of the Reuters group of companies around the world.

Smokers must quit, not just cut down, study finds

Last Updated: 2006-11-28 16:33:00 -0400 (Reuters Health)

By Patricia Reaney

LONDON - Smokers eager to cut the risk of dying early from tobacco-related illnesses must quit completely, researchers said on Tuesday, because cutting down -- even by half -- is not enough.

"Smokers should quit -- you can't give your health a better present than to quit smoking," said Dr Kjell Bjartveit, former director of the National Health Screening Service, in Oslo.

In a 20-year study of 51,000 men and women in Norway, Bjartveit and his team studied the impact of cutting down smoking on deaths from heart disease, lung cancer and other tobacco-related cancers.

All the people at the start of the study were between 20-34 years old. They were assessed for their risk of suffering from cardiovascular disease at the beginning of the project and twice during the 20-year follow up period.

The aim of the research, published in the journal Tobacco Control, was to determine the health benefits if heavy smokers who got through more than 15 cigarettes a day cut their consumption by half or more.

"The long-term effects of a substantial reduction in smoking did not show any benefits in comparison with persistent heavy smoking," Bjartveit told Reuters.

The researchers found no significant difference in early death rates from cardiovascular disease, cancers and other causes between heavy smokers who continued their habit and people who had halved their consumption during the study.

The results were the same for both men and women.

"In health education and patient counseling, it may give people false expectations to advise that reduction in consumption is associated with reduction in harm," Bjartveit added.

Smoking is a leading cause of preventable death. In addition to being a risk factor for heart attack and stroke and certain types of cancer, it is also the leading cause of lung cancer and chronic obstructive pulmonary disease (COPD) which includes chronic bronchitis and emphysema.

Health experts estimate the annual global deaths associated with smoking could double to 10 million or more by 2020.

"The study proves quite clearly the only safe way out of the risk caused by smoking: people who quit smoking have achieved a risk level that is remarkably lower than those who continued to smoke," Bjartveit said in the journal.

Copyright © 2006 Reuters Limited. All rights reserved. Republication or redistribution of Reuters content, including by framing or similar means, is expressly prohibited without the prior written consent of Reuters. Reuters shall not be liable for any errors or delays in the content, or for any actions taken in reliance thereon. Reuters and the Reuters sphere logo are registered trademarks and trademarks of the Reuters group of companies around the world.