Predictive value of galactographic patterns for benign and malignant neoplasms of the breast in patients with nipple discharge.

The purpose was to identify features of malignant and non-malignant neoplastic breast disease on galactography and to estimate their predictive value. This is the largest reported study correlating galactographic morphological patterns with histopathology and the only blinded study. The study included 351 consecutive galactograms and 161 breast biopsies performed in patients with nipple discharge over a 10-year period. Three radiologists, blinded to clinical data and histological results, re-evaluated 158 previously performed galactograms of patients who had undergone excision biopsy. Extravasation or incomplete filling precluded reading in 9.5% of examinations. Among the remaining 143 examinations there were 11 cancers (7.7%), 56 papillomas (39.2%), 19 cases of intraductal papillomatous proliferation (13.3%), 55 cases of fibrocystic or secretory disease (38.5%) and two normals. A "filling defect/cut-off" pattern (n = 90) was found in 6 cancers (6.7%) and 58 cases of papilloma or papillomatous proliferation (64.4%). A "leafless tree" pattern was found only in benign cases (n = 12; 8.4%). In 32 of 143 cases (22.4%) a "ductal ectasia" pattern was present, in one case of which (3.1%) cancer was found. Cancer was identified in two of four cases with an "architectural distortion" pattern. Cancer is rare in patients with nipple discharge. A tendency towards a lower incidence of cancer associated with the "ductal ectasia" and "leafless tree" patterns was found. No statistical evidence was found to indicate that galactography provides an effective prospective diagnosis of malignancy. However, an abnormal galactogram strongly correlated (p < 0.001) with the presence of a breast neoplasm when both benign and malignant tumours were considered. The most important role played by galactography is in the localization of breast neoplasms and in the choice of appropriate surgical therapy.