Answer 1: C. Fat necrosis.
Answer 2: B. Suture material.
Comment: Fat necrosis is not a common lesion found in the breast, although it is of clinical importance since a mass is often produced. The most common cause is trauma, although some patients do not recall an injury. The skin can appear retracted and the nipple can exhibit a bloody or straw-colored discharge. The tissue injury results from release of triglycerides and lipases from the adipocytes. With time, saponification of the lipid can occur and there is deposition of a white chalky residue which often becomes infiltrated with calcium.
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