NEWCASTLE, AUSTRALIA. X-ray mammography is widely used to screen women for breast cancer. Unfortunately, mammography is not very accurate and can produce a significant number of false positives (no cancer present) and false negatives (cancer present, but not detected). The test can be very painful due to the compression of the breast necessary for clear pictures and there is some evidence that this compression can actually promote or spread existing cancer. There are several alternative screening tests available, but none have been able to dislodge x-ray mammography from its preeminent position. Medical researchers at the John Hunter Hospital in Australia now suggest that scintimammography may be superior to x-ray mammography in many ways.
Scintimammography makes use of a radioactive tracer (Technetium-99m) which is
injected into a vein followed by examination of the breasts by a gamma camera. The new
test can be done using standard equipment available in any nuclear medicine department.
The researchers examined 115 women scheduled for breast cancer surgery using x-ray
mammography, scintimammography, and ultrasound examination and fine needle biopsy
where appropriate. Of the 96 confirmed cancer cases scintimammography correctly
identified 81 whereas standard mammography identified only 61. Similarly, while
scintimammography failed to detect 15 existing cancers x-ray mammography failed to
detect 31 cases. X-ray mammography also indicated that six out of 19 non-cancerous
women had cancer while the number of false positives with scintimammography was only
three out of 19. Scintimammography was found to be vastly superior to x-ray
mammography in detecting cancer in patients who had had previous breast surgery or
radiation treatments. The researchers conclude that scintimammography has the
potential to prevent unnecessary breast biopsies and offers additional advantages in
patients who have already undergone treatment for breast cancer.