Scan promises early cancer detection

A typical mammogram - the bright spot is a patch of dense tissue

A new method of analysing mammograms should help doctors reliably spot smaller tumours than ever before, scientists predict.

This could mean that smaller cancers missed in some mammograms could be noticed and treatment given earlier, when it has far more chance of succeeding.

A common complaint about the current mammogram system is that the resulting images can vary widely in appearance - even when the same operator is using the same machine.

Somehow, experts must work out the size of the bright areas on the slide which may correspond to the dense breast tissue in a tumour, although the size of the bright patch can also vary widely.

The latest technique could overcome this problem by using computer technology to counteract the variations and come up with an image that reliably represents the size of the mass.

Developed by Professor Michael Brady and colleagues at the University of Oxford, it is claimed the system will detect lumps as small as 1mm across - a tenth of the size of those spotted in traditional mammograms.

It's impossible to underestimate the value of early diagnosis of breast cancer

Professor Gordon McVie, Cancer Research Campaign

NHS Breast Screening is offered once every three years to all women aged between 50 and 64.

It is estimated that the programme has saved many hundreds of lives over the past few years - in just one year, between 1998 and 1999, 3,722 small breast tumours (less than 15mm across) were spotted.

Seven out of 10 breast cancers are now cured by treatment.

'Bright spot'

Professor Brady said: "A mammogram shows a lump as a bright patch on a grainy background, but that same patch will look different on another machine.

"It will look different if a different x-ray film is used, or if it developed differently. It will change even if the same machine is used, but someone else takes the picture.

"The exact size of that patch is a guess, and so is the size of the tumour it represents."

He said: "We have found a way of eliminating all these variations and leaving only the interesting information.

"Using our method, a bright patch will always look the same."

The research team is now trialling their method in a sample of 500 apparently-healthy women.

Professor Gordon McVie, director general of the Cancer Research Campaign, said: "It's impossible to overestimate the value of early diagnosis of breast cancer.

"If this research is successful we will be able to spot breast cancer in its very early stages. For some women this will mean they do not lose a breast, and for others it may mean they do not lose their lives."