Microwave Radiometry and Breast Cancer by Jo Gordon

The Problem

Breast cancer is a major medical problem of our times. There has been a significant increase in the incidence of breast cancer during the past forty years. The key to optimistic prognosis depends on early diagnosis.

It is estimated that one in seven women in the UK is likely to experience breast cancer at some time during her life (there is also an increase in male breast cancer, a rare condition a few years ago). The reason for the increase is not known but the statistics must be of concern to all those affected and their doctors. Early detection is crucial to effective treatment. Unfortunately, current methods of screening are not always sufficiently sensitive. There is also the problem that fast growing; aggressive tumours require frequent screening. Mammography is not always appropriate for this purpose. Microwave radiometry offers a safe means of screening for all, regardless of age.

What is Microwave Radiometry?

The tissues of the body emit natural radiation in the microwave frequency band. The intensity of radiation is in direct proportion to the temperature of the tissue. Thus, microwave radiometry is a non-invasive means of detecting internal tissue temperature.

Infrared thermography is a well-known method of superficial screening. Unfortunately, infra-red thermography has only a very limited depth of penetration – approximately 2 mm. Microwave radiometry detects signals at a much greater depth, ranging from 2 millimetres to seven centimetres, depending on the water content of the tissue. The breast, being soft tissue, provides an ideal organ for radiometry examination.

Comparisons

Ultrasound is the current preferred method for screening younger women (under 45 years). Unfortunately, ultrasound is less accurate than other methods, the reliability being

estimated at 74%. Ultrasound is helpful where the mass is dense, well formed, and with well-delineated boundaries.

Mammography is the preferred method of screening for women aged over 50. It is less useful for pre-menopausal women due to the density of the breast tissue. The accuracy of mammography is also dependent upon the density of the tumour mass and the definition of the boundary. The reliability of mammography is estimated as 84%.

Microwave radiometry is a relatively new method of screening. It does not rely on tumour density or well-defined boundaries. The sensitivity of microwave radiometry relies on the fact that most tumours show thermal changes in the tissue even before a mass is detectable by other means. Clinical trials in four Russian specialist hospitals have shown the reliability figure to be as high as 92%. It is interesting to note that false positives (indications of possible cancer that were not able to be verified by other means) were counted as false results. However, follow up studies showed that all false positives were proven to be cancerous within a three-year period.

Clinical Trials

Full clinical trials have been conducted at four Russian specialist hospitals. It is interesting to note that these hospitals now refer women for radiometry screening when other diagnostic methods are inconclusive.

The Radio-Thermometer

The apparatus is lightweight, compact and portable. It is linked to a PC that records all data and also guides the operator through the measurement procedure.

It should be noted that care must be taken when choosing a suitable location. The ambient room temperature must be constant at 20 – 23 degrees, and there must be no stray microwave radiation from nearby apparatus. The PC must also be screened because the radio thermometer is sufficiently sensitive to pick up stray signals from the computer.

Advantages of Radiometry Screening

• No signal is passed into the body. There are no radiation hazards and thus, it is completely safe for both patient and operator.
• Because tissue temperature changes before detectable pathology this method offers an ideal means for early detection of possible malignant states.
• The heat generated by a tumour is in direct proportion to the doubling time of the tumour. Thus, with regular screening more aggressive tumours can be detected at an early stage.
• Proliferative cell active in non-malignant states can be inferred.
• Radiometry also offers the possibility of monitoring the effects of treatment for a variety of breast diseases. The major exception is when radiotherapy has been used.
• There is no restriction on age. The procedure is equally applicable to young women as to older women. The examination can be repeated as often as required without any danger.
• The breast does not need to be compressed during examination and thus does not cause pain to the patient.
• Finally, the procedure is very cost-effective because it does not require a highly trained radiographer. A trained operator carries out the screening process, with a doctor making the final interpretation of the results.

Copyright 2007 Jo Gordon.Jo is a qualified nurse with 35 + years experience, she has also been trained in many forms of complementary and alternative medicine.
To find out more, her web site is - www.atime2heal.co.uk