Imperfect correlation of mammographic and clinical breast tissue density.

Background: Clinicians determine degree of mammographic density based on tissue firmness on breast examination. The study aimed to compare breast density in mammography and clinical breast examination.

Materials And Methods: Six-hundred sixty three women 40 years of age or older were studied. The breast exam density was graded from 1 to 4 by two expert surgeons and the mammographic parenchymal density by two expert radiologists. Then for practical reasons, grades 1 and 2 were considered as low-density and grades 3 and 4 as high-density.

Results: High and low densities were detected in 84.5% and 15.5% of clinical breast examinations and 59.7% and 40.3% of mammographies, respectively. The statistical analysis showed a significant difference between the breast tissue densities in breast examination with those in mammography.

Conclusions: A clinically dense breast does not necessarily imply a dense mammographic picture.