Mammography: Ducts as a Sole Indicator of Breast Carcinoma

Breast cancer may occasionally be diagnosed by the observation of a unilateral group of dilated ducts, in the absence of tumor calcifications or a recognizable mass. The carcinoma is more likely to be scirrhous than any other type; early, as evidenced by no involvement of lymph nodes with metastatic disease and no palpability. The purpose of this article is to describe and illustrate those cases in which abnormal ducts can lead to a correct diagnosis of breast cancer. To make this point, it is well to discuss first and illustrate briefly the usual roentgenographic relationships of breast cancer and ductal patterns. Comedocarcinoma Comedocarcinoma may have several anatomic forms, one of which is a prominent duct pattern containing typical tumor calcifications (Fig. 1). The duct change is bilateral and more or less equal, and the diagnosis is usually based on the calcific deposits in the absence of a tumor-exhibiting invasion. Bilateral Ducts with Unilateral Prominence The patient with breast cancer is likely to have a prominent duct pattern. A further extension of this is that, with this generalized change, the breast containing the cancer is apt to be more severely involved than the opposite (Fig. 2). The finding is noted most often as one compares the subareolar area where ducts are most readily identified. Another manifestation can be seen in the patient who has nipple retraction as a result of carcinoma. It matters not whether or not the cancer is deeply placed, the ducts “tying” the cancer and nipple together can be seen on the roentgenograms. The mechanics are obvious; the contraction around and within the scirrhous growth shortens the associated ducts to produce the retraction (Fig. 3). Unilateral Duct Prominence The topic under main discussion concerns those cases in which one of two situations exists: a poorly limited group of prominent ducts observed in one breast without any other abnormality, and the occurrence of a solitary or, at most, few discrete large tortuous ducts leading from the nipple to a cancer within the breast, either superficially or deeply placed. The limited, unilateral group of prominent ducts permits the diagnosis of cancer even in the absence of tumor calcifications, and the neoplasm is likely to be of the scirrhous type and often discovered only after careful search by the pathologist (Figs. 4 and 5). The ducts have exhibited varying degrees of hyperplasia, ranging from that amount commonly seen and believed unimportant by the pathologist to that exhibiting a high degree of epithelial change bordering on and being in some instances atypical. The other situation in which unilateral ductal prominence aids in the diagnosis of breast cancer occurs when one observes one or a few tortuous ducts leading from the nipple into the parenchyma of the breast. This latter type is prone to have a bloody nipple discharge, the mechanisms of which are apparent.