Breast Tumors Grow Faster in Younger Women
Reported May 13, 2008
(Ivanhoe Newswire) — The growth rate for breast cancer tumors varies considerably, but a new approach to estimate the growth speed based on screening shows that they grow faster in younger women.
Harald Weedon-Fekj of the Department of Etiological Research Cancer Registry of Norway reports this model of estimating tumor growth is based on breast screening results from almost 400,000 women included in the Norwegian Breast Cancer Screening Program.
The research shows one in 20 tumors double in size in just over a month from 10 to 20mm, while a similar number took more than six years to grow. The average time it took for a tumor to grow from 10 to 20mm was 1.7 years.
Weeden-Fekj says he and his team found that, as expected, mammography screening test sensitivity increases with larger tumors. He reports detection rates are 26 percent for a 5mm tumor and increase to 91 percent for one that is 10 mm.
Previous tumor growth rate models were based on small, selected samples. This model, says Weeden-Fekj has enormous implications for sensitivity of beast cancer screening programs. He also reports the team compared their model to the previously used Markov model for tumor progression and found its predictive power to be twice as accurate in addition to providing new estimates directly linked to tumor size.
SOURCE: Breast Cancer Research, published online May 7, 2008
