WEDNESDAY, Sept. 14 (HealthDay News) -- The annual rate of breast surgery increased significantly from 1993-1995 to 2005-2008 for women in Norway aged 50 to 69 years who were invited to undergo mammography screening, according to a study published online Sept. 13 in BMJ.
Pål Suhrke, from Oslo University Hospital in Norway, and colleagues investigated the effects of mammography screening on surgical treatment for breast cancer in 35,408 women with invasive breast cancer or ductal carcinoma in situ, treated surgically between 1993 and 2008. Breast surgery and mastectomy rates were analyzed in three groups: invited group (aged 50 to 69 years), younger non-invited group (aged 40 to 49 years), and older non-invited group (aged 70 to 79 years). The change in rates from the pre-screening period (1993 to 1995) to the introduction of screening phase (1996 to 2004) to screening period (2005 to 2008) was assessed.
The investigators found that the annual rate of breast surgery from pre-screening to the screening period increased by 70 and 8 percent in the invited and younger non-invited groups, respectively, and decreased by 8 percent in the older non-invited group (hazard ratio [HR], 1.70, 1.08, and 0.92, respectively). The rates of mastectomy decreased similarly for invited and non-invited women from the pre-screening to screening period. However, the annual mastectomy rate from pre-screening to introduction of screening increased by 9 percent in the invited group and decreased by 17 percent in the younger non-invited group (HR, 1.09 and 0.83, respectively). Compared to the non-invited younger group, the mastectomy rate was 31 percent higher in the invited group (HR, 1.31).
"Mammography screening is associated with a noticeable increase in breast surgery rates," the authors write.