Correlation Between Imaging and Pathologic Measurement of Breast Cancer Tumor Size

Background: Our study aims to determine the correlation between breast cancer tumor size according to imaging (ultrasonography and mammography) with final pathologic report as a gold standard. Methods: We included 132 women with pathologically proven invasive breast cancer between April 2011 and December 2013. Study variables included tumor size according to pathology (as a gold standard), ultrasonography and mammography. Pearson correlation coefficient was used to show correlations. Results: A total of 132 patients were included in the final analysis. The correlation coefficient between tumor size in mammography and pathology was 0.74 (P < 0.001) and between ultrasonography and pathology was 0.67 (P < 0.001). Age had a modifying effect on the correlation between mammography and pathology; the correlation coefficient in women who aged 40 years or above was 0.92 (P < 0.001) and in women younger than 40 years was 0.74 (P < 0.001). Similarly, regarding the association between ultrasonography and pathologic tumor size, higher correlation coefficient was observed for women aging 40 years or above compared with their younger counterparts (0.74 versus 0.62, respectively). Conclusions: measuring tumor size in mammography whenever possible would be recommended considering the higher and significant observed correlation with the pathologic tumor size compared to ultrasonography. Both associations were stronger in women aging 40 years and above.