Densely calcified metaplastic carcinoma of breast: An undescribed mammographic feature

Abstract

A 48-year-old lady presented with a palpable lump in left breast for the last two years. On examination, there was a large nontender, hard lump occupying almost entire breast with edema of the overlying skin and ulceration of the nipple-areola complex (Figure 1). An enlarged, mobile, hard lymph node was palpable in the ipsilateral axilla. Examination of the opposite breast and axilla was unremarkable.Bilateral mammography showed a large, lobulated, isodense mass with indistinct margins involving the entire left breast. The mass showed large, lobulated heterogeneous calcification with areas of dense calcification resembling bone ( Figure 2). Thus, the imaging differential of sarcoma was considered. Ultrasonographic examination revealed a 14 × 12 × 9 cm solid cystic mass with increased vascularity in the solid areas. Left axilla showed multiple enlarged lymph nodes with loss of fatty hilum. Left breast lesion was classified BIRADS 5 according to ACR BIRADS lexicon. The histopathologic examination of the mass showed malignant cells with numerous osteoclast type of giant cells, and chondro-osseous and rhabdoid differentiation and diagnosis was made of heterologous type of metaplastic carcinoma ( Figure 3A and B). Immunohistochemistry (IHC) was negative for ER, PR, and HER-2/Neu and showed moderate positivity for CK5/6 and strong positivity for vimentin consistent with metaplastic carcinoma ( Figure 3C and D).Metaplastic carcinoma of breast is a rare, aggressive breast tumor accounting for less than 1% of all invasive breast cancer. It is called "metaplastic" as there is differentiation of glandular epithelium into various nonglandular, epithelial (like squamous cell and spindle cell) and mesenchymal (like bone and cartilage) components.It usually presents as a rapidly growing palpable mass in women older than 50 years. There are no specific imaging features, and it can show imaging appearances similar to malignant as well as probably benign masses. On mammogram, they usually appear as high density, round to irregular mass with circumscribed to noncircumscribed (obscured, indistinct, or spiculated) margin. They are often noncalcified with the incidence of calcification being <25%. Calcifications are frequent in rare, matrix-producing subtype of metaplastic carcinoma which demonstrates calcifications due to mineralization of cartilaginous and osteoid matrix. The common patterns of calcification, if present, are amorphous, coarse, punctate, or pleomorphic, and none of the previous studies have demonstrated large dense calcifications in metaplastic breast carcinoma. Mammogram in our case demonstrated a mass with a large, lobulated heterogeneous calcification showing patchy areas of dense calcifications resembling bone, due to mineralized osteoid matrix. This pattern of large dense calcification has been described in breast sarcomas. Metaplastic breast carcinoma needs to be differentiated from breast sarcomas as these vary in their management approach and patient outcome. It is, however, challenging to differentiate them ...

Metaplastic breast carcinoma: sonographic and clinicopathologic comparison with infiltrating ductal carcinoma

“…Another article with 65 MBC patients came to similar conclusions, MBC demonstrated benign or moderately malignant features on imaging methods, MRI might comparatively provide more malignant features than other imaging modalities [24]. MBC can be diagnosed by T2-weighted imaging with high signal intensity due to cystic or necrotic components, although it must be differentiated from mucinous carcinoma and, less frequently, necrotic IDC [22,25]. Mammographically, the most frequent presentations of MBC were round/ oval shape, high density masses, and calci cations were not a frequent nding.…”

Metaplastic Carcinoma of the Breast: Case Series of a Single Institute and Review of the Literature

“…Therefore, these 77 articles were excluded. Overall, 65 studies [ 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 , 61 , 62 , 63 , 64 , 65 , 66 ...…”

Sonographic and clinicopathologic features of metaplastic breast carcinoma and infiltrating ductal carcinoma: a comparative single-center cohort study

“…Mammographically, MBC typically presents as round or oval-shaped high-density masses, with calcifications being a less frequent finding. However, MBC with osseous differentiation may present as a densely calcified lesion on mammography ( 20 , 30 ). Günhan-Bilgen et al ( 12 ) analyzed eight patients with MBC, in whom the tumor exhibited high density and lacked prominent spiculations, microcalcifications, and architectural distortion on mammography.…”