CAD software improves detection of breast cancer
28 September 2005
Sunnyvale, Calif, USA. Detection rates for small, invasive breast cancers
(1.0 cm or less) increased by 164% and cancers were found in women at a
younger age when radiologists used computer aided detection (CAD) to assist
in reading mammograms, according to a new study published in the October
issue of the American Journal of Roentgenology (AJR).
The mean age at screening detection of cancer with CAD was 5.3 years
younger than in those for whom CAD was not used. Overall, the study found
that detection rates for breast cancer increased by 16.1%. The study used R2
Technology, Inc.'s ImageChecker (R) mammography CAD system and is the first
to prospectively evaluate in a clinical practice CAD's impact on both the
size of tumours detected and women's age at diagnosis.
"Finding breast cancer when it is small and localized can be critical to
a woman's survival," said lead investigator Dr. Tommy E. Cupples, of the
South Carolina Comprehensive Breast Center at Palmetto Richland Memorial
Hospital in Columbia, SC. "Our use of R2's CAD helped to substantially
increase detection of small, invasive cancers, which are often the easiest
for radiologists to miss and can thus be life-threatening for women.
Additionally, our study showed that CAD can help radiologists find these
cancers in women more than five years younger — thus, helping us find the
cancers potentially five 'mammography cycles' sooner. Earlier detection can
have important implications for a woman's prognosis and survival."
The new study, conducted in a regional hospital between January 1, 1998,
and December 31, 2000, evaluated radiologists' performance on 7,872
consecutive screening mammograms before CAD was installed at the Center and
then compared the results with the same radiologists' performance on 19,402
consecutive exams, when using CAD. The study measured recall rates, biopsy
rates and cancer detection rates, as well as the type, size and stage of
cancers found by screening with and without CAD. The number of women
recalled for subsequent evaluation increased by only 8.1%, while the number
of women in whom biopsies were performed increased by only 6.7%, coincident
with an important increase of 16.1% in breast cancer detection rates.
This study underscores the increasingly important role that R2's
ImageChecker(R) CAD system plays in helping physicians detect breast cancer
earlier," said Dr. Ronald A. Castellino, R2 Technology's chief medical
officer. "Our technology should give radiologists added confidence that they
are providing their patients with the best care possible."
This year, more than 200,000 women in the United States will be diagnosed
with invasive breast cancer and more than 40,000 women will die from this
disease, according to American Cancer Society (ACS) estimates. When
diagnosed at an early stage, when the tumor is confined to the breast, the
ACS estimates that a woman's five-year survival rate is 98%. Once the cancer
has spread regionally, the five-year survival rate drops to 80% and then to
26% for women with distant metastases. The ACS recommends that women age 40
and older should get screening mammograms every year.
CAD technology is used by increasing numbers of radiologists as "a second
pair of eyes" when reading mammograms. Five independent prospective clinical
studies* from academic and community practices showed that the use of R2's
CAD resulted in 6.6%to 19.5% more cancers detected. Independent studies*
comparing CAD performance on architectural distortions, cases graded by
difficulty, and small invasive breast cancers all demonstrate the advantage
of R2's market-leading CAD algorithm.