Breast conservation therapy extended disease-specific survival in early-stage invasive ductal carcinoma

Women who underwent breast conservation therapy for early-stage invasive ductal carcinoma experienced longer breast cancer-specific survival than those who underwent mastectomy alone or mastectomy plus radiation, according to study results.

Researchers used the SEER database to identify 132,149 women with early-stage invasive ductal carcinoma treated with breast conservation therapy (70%), mastectomy alone (27%) or mastectomy plus radiation (3%) between 1998 and 2008.

The breast cancer-specific survival rate at 5 years was 97% in women who underwent breast conservation therapy, 94% among those who underwent mastectomy alone, and 90% among those who underwent mastectomy plus radiation (P<.001).

At 10 years, breast cancer-specific survival rates were 94% among those who underwent breast conservation therapy, 90% for those who underwent mastectomy alone, and 83% among those who underwent mastectomy plus radiation (P<.001).

Researchers determined breast conservation therapy was associated with improved breast cancer-specific survival compared with mastectomy alone (HR=1.31; P<.001) or mastectomy plus radiation (HR=1.47; P<.001).

“The finding of improved survival with breast conservation therapy in this large database study could be due to differences in adjuvant therapy regimens or tumor biology,”  the researchers wrote. “These findings deserve further investigation to determine which factors may be contributing to this effect.”