Differences between screen-detected and interval breast cancers among BRCA mutation carriers.

1529Background: BRCA mutation carriers have an elevated lifetime and interval breast cancer risk. We sought to compare BRCA mutation carriers with screen-detected versus clinically detected, interval breast cancers. Methods: Women with a known BRCA mutation prior to a breast cancer diagnosis were identified. Clinical and pathologic factors, and imaging within 18 months of diagnosis were compared among screen-detected vs clinically detected/interval cancers. Clinically detected tumors were those detected by physical exam regardless of screening history, whereas interval cancers were those detected by physical exam among women undergoing regular screening. Results: Of 115 breast cancers, 93 were screen and 22 clinically detected, of which 11 were interval cancers among regular screeners. Women with clinically detected/interval cancers were younger, had lower BMIs, and were more likely to be Black than those with screen-detected cancers (p < 0.05). Clinically detected/interval cancers were all invasive, were...