Osteoid containing breast masses: A rad-path correlation

Abstract

Objectives: Breast cancer is very common, of which the most common subtype is invasive ductal cancer (IDC). However, there are some rare types that also occur and manifest radiologically in a different manner. Our article aims to emphasize a rare type of breast neoplasm, which shows osteoid matrix on pathology, and to correlate their imaging findings, thus enabling differentiation from usual carcinoma and aiding in further pathology typing. Material and Methods: A retrospective audit of breast masses with osteoid matrix was done from 2008 to 2021. The cases were retrieved from pathology archives. Twenty-five such cases were found with histopathology reports mentioning the osteoid matrix. Eight patients from these 25 had pre-operative mammograms as well as histopathology available for review. We evaluated these with mammograms with multiple parameters. The project was approved by the Institutional Ethics Committee. Waiver of consent was obtained since there was no direct contact between the researcher and the participants. Results: Most cases of eccentric coarse calcification seen on mammography showed type IV matrix, in turn meaning that these cases had mature bone formation with tumor cell rimming type on histopathology. Three tumors produced an osteoid matrix in our study, namely, Metaplastic carcinoma, primary osteosarcoma, and malignant phyllodes tumor. Coarse calcification mostly indicates metaplastic carcinoma with osteosarcoma element. The preoperative diagnosis can guide pathology sampling. Conclusion: When eccentric, large, and coarse calcifications are visible within a mass on a mammogram, it raises suspicion of mature bone formation with tumor cell rimming within the tumor matrix.