Severity of mastalgia in relation to milk duct dilatation

The etiology of mastalgia is poorly understood. Histology cannot detect any distinct characteristics. This investigation therefore applied ultrasonography to mastalgia patients to investigate morphological structures and to obtain further insights into the pathophysiology of mastalgia. The aim of the study was to analyze the significance of milk duct dilatation in patients with mastalgia.

A total of 335 premenopausal women participated in a genital and breast cancer screening program. Of these, 123 women were asymptomatic and 212 complained of breast pain (136 had cyclical mastalgia; 76 reported the noncyclical type). The width of milk ducts was measured by ultrasonography and correlated with the intensity of breast pain. The site of the pain was correlated with duct dilatation. Statistical analysis was performed using the t test, the chi(2) test, analysis of variance, and Pearson correlation.

In asymptomatic women, the maximum mean width of the milk ducts was 1.8 +/- 0.84 mm, in cyclical mastalgia 2.34 +/- 1.10 mm, and 3.89 +/- 1.26 mm in noncyclical mastalgia (P <.001). The intensity of pain showed a significant, positive correlation with the width of the milk ducts (r =.5008, P <.001). Noncyclical mastalgia patients located the pain at the site where dilated ducts were detected ultrasonographically (P <.001).

The results of this study demonstrate that duct ectasia is a major factor in mastalgia. The degree of duct dilatation correlates positively with the intensity of breast pain. In the noncyclical type of pain, there is a positive correlation between the site of duct dilatation and the site of pain.