Intratumoral ^99mTc-DPD Uptake on Bone Scintigraphy in a Patient With Invasive Micropapillary Breast Carcinoma: A Pathologic Review

Invasive micropapillary carcinoma (IMPC) is a rare and aggressive subtype of breast cancer with a poorer prognosis due to high local recurrence and lymphovascular invasion. Interestingly, IMPC often does not show suspicious patterns of calcifications related to malignancy on mammography. Therefore, the lack of suspicious calcifications makes it difficult to detect breast cancer on mammography. With only nonspecific calcifications on mammography, we observed an unusual intratumoral Tc-99m-DPD uptake on whole-body bone scintigraphy in an IMPC breast cancer patient during the initial staging workup, and its characteristics were compared with mammographic findings and the postoperative pathologic features.