What symptom of possible breast disease is often not visible on a mammogram?

Nipple discharge is considered a symptom of possible breast disease that is often not visible on a mammogram. Mammography primarily detects structural changes in breast tissue, such as masses or calcifications, but it does not provide information about fluid dynamics or discharge from the nipple.

Nipple discharge can be a sign of conditions ranging from benign breast diseases to malignancies, but unless a specific lesion is identified on the imaging study that correlates with the discharge, it will typically not appear on a mammogram. This makes it a critical symptom for clinicians to consider, but one that might necessitate further evaluation through additional imaging or biopsy instead of relying solely on mammographic findings.

In contrast, other symptoms such as palpable lumps, skin irritations, and breast pain may have corresponding imaging findings that can be evaluated through mammography or other imaging modalities.