What characterizes a mammographically malignant tumor?

A mammographically malignant tumor is primarily characterized by irregular borders and the potential for invasion. These features indicate an aggressive behavior typical of cancers, as malignant tumors often exhibit an infiltrative growth pattern that disrupts the normal architecture of the breast tissue. Irregular margins suggest that the tumor is likely penetrating into surrounding tissues, which is a hallmark of malignancy.

In contrast, well-defined edges and uniform shape typically suggest benign lesions, which are not invasive and have clearer boundaries. The presence of distinct halo signs can occur in certain benign conditions but is not a definitive characteristic of malignant tumors. Finally, tumors composed exclusively of cystic structures are generally indicative of benign conditions, such as cysts or fibroadenomas, rather than malignancies. Recognizing these characteristics is essential in mammography for accurate diagnosis and appropriate management of breast lesions.