RADIOLOGY: BREAST: Case# 32943: INVOLUTING FIBROADENOMA. 58 Year old for screening mammogram. Close up view of the mammogram shows a small mass with large, dense calcifications. Involuting fibroadenomas may calcify. Usually they calcify from the center outward, with large dense calcifications. Heavily calcified lesions may have the appearance of calcified popcorn. These large calcifications are characteristic and benign. Occasionally, early involuting fibroadenoma may calcify with small, irregular calcifications, indistinguishable from malignant calcifications.