Tumor registry audit of mammography in community practice

The 395 analytic breast cancers logged into a community hospital tumor registry from 1988 to 1992 included information as to (1) the mode of detection and (2) the time interval since prior mammography. Mammography alone detected 44% of the cancers in women under 50 years of age and 47% of the cancers in women over 50 years of age. The American Joint Committee on Cancer's 1988 "Manual for Staging of Cancer" TNM staging of mammographically detected cancers in both age groups was similar, ie, there were 89% stage 0/1 in women aged under 50 and 86% in women over age 50. Twenty-one percent of the mammographically detected cancers were in women under age 50, whereas a disproportionate 36% of the "interval cancers" occurred in this group. A ratio of the number of mammographically detected cancers to the number of interval cancers was 5.8 in women over age 50 and 2.7 in women under age 50. This ratio fell to 1.7 when the time interval following prior mammography was 2 years. Correctable errors accounted for 21% of the interval cancers.