Radiotherapy boost helps early breast cancer: study

Last Updated: 2006-07-06 11:30:02 -0400 (Reuters Health)

LONDON - A booster dose of radiotherapy added to regular treatment may help stop young women with very early breast cancer from progressing to a more serious form of the disease, researchers said on Thursday.

Ductal carcinoma in situ (DCIS) is contained within the cells lining the milk ducts of the breast that has not yet spread to the surrounding breast tissue. Surgery is usually performed to remove the cells and prevent recurrence. If the DCIS is extensive, a mastectomy may be necessary. Radiotherapy can also be used to kill any remaining cancer cells.

Scientists who compared different treatments for DCIS said their findings show radiotherapy plus a boost dose improves the patients' chances.

"First, not using radiotherapy in young patients with DCIS resulted in an unacceptable number of women having their cancer return and second, these patients benefit from an additional boost dose," said Guenther Gruber of the Kantonsspital in Aarau, Switzerland.

He and a team of researchers analyzed the outcomes of 373 women 45 years old or younger who had been treated at 18 different institutions throughout the world for DCIS.

One sixth had surgery to remove the DCIS. Nearly half had surgery plus radiotherapy, and the remainder had surgery, radiotherapy and a boost dose.

The risk of a recurrence of DCIS or invasive breast cancer decreased with each additional treatment.

"Our findings clearly suggest that the radiation dose is very important for local tumor control for patients with DCIS aged 45 years or younger," Gruber said in a report in The Lancet Oncology journal.

Advances in breast screening have led to an increase in the number of women diagnosed with DCIS. If it is not treated, DCIS can develop into invasive cancer.

Although more research is needed, the scientists said radiotherapy of the whole breast followed by a boost dose should be considered for breast-conserving treatment in young patients with DCIS.

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.

Scientists build theory on human face recognition

Last Updated: 2006-07-06 12:15:02 -0400 (Reuters Health)

LONDON - Monkeys recognize each other by comparing faces to a statistical average stored in their brains, not by memorising what each individual looks like, scientists said on Wednesday. This probably applies to people, too, explaining how faces can be recognised in a fraction of a second, they said.

In their study, the scientists found that a monkey's brain does not keep track of different parts of a face, storing and then accessing the information to recognize others. Instead, it keeps a statistical average of the faces it has seen and uses it as a basis for comparison.

"When it sees a new face it compares it to this average and then it remarks upon the differences ... and that is how the face is seen," said David Leopold, of the National Institute of Mental Health in Bethesda, Maryland.

"It elucidates how it is possible that you can so quickly and effortlessly, in just a few hundred milliseconds, recognize faces," he added.

Leopold and his colleagues pinpointed the recognition system while studying neurons in an area of the brain called the inferotemporal cortex in two macaque monkeys that had been trained to recognize computer-generated human faces.

They monitored single neurons to understand how groups of the brain cells work together to recognize faces.

"What we found is that the neurons in this part of the monkey's brain respond in a way that is extremely sensitive to the small differences in information between faces of different identities," said Leopold, who reported the research in the science journal Nature.

The activity of the neurons was monitored as the monkeys were shown an average face of a person and as it was artificially morphed the full identity.

"The main finding was a striking tendency for neurons to show tuning that appeared centered about the average face," Leopold writes in the journal.

In psychological tests, humans identify faces in much the same way as monkeys so the researchers believe this aspect of the visual recognition system is similar in both species.

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.