(HealthDay News) – From 1990 to 2008 there was a significant increase in mammography-detected breast cancer, which coincided with lower-stage disease detection, according to research published in the March issue of Radiology.
Judith A. Malmgren, PhD, from the University of Washington in Seattle, and colleagues prospectively studied a longitudinal cohort of 1,977 women (aged 40 to 49 years) who had primary breast cancer during 1990 to 2008. The method of detection — patient detected (PtD), physician detected (PhysD), or mammography detected (MamD) — was abstracted from charts.
The researchers found that, from 1990 to 2008, there was a significant increase in the percentage of MamD breast cancer over time (28 to 58%) and a concurrent decline in PtD/PhysD breast cancer (73 to 42%). There was an overall increase in lower-stage disease detection and a decrease in higher-stage disease. Compared with PtD/PhysD patients, MamD patients were more likely to undergo lumpectomy (67 vs. 48%; P<0.001) and less likely to undergo modified radical mastectomy (25 vs. 47%; P<0.001). Significantly fewer MamD breast cancer patients underwent surgery and chemotherapy (13 vs. 22%; P<0.001) and surgery, radiation therapy, and chemotherapy (31 vs. 59%; P<0.001), uncorrected for stage. For patients with invasive cancers only, five-year relapse-free survival for MamD breast cancer patients was significantly higher (92 vs. 88%; P<0.001).
“Increased mammography-detected breast cancer over time coincided with lower-stage disease detection resulting in reduced treatment and lower rates of recurrence,” the authors write.
One of the authors disclosed financial ties to Hologic and has been paid for expert testimony in medical malpractice litigation.