Do primary mammary osteosarcoma and chondrosarcoma exist? A review of a large multi-institutional series of malignant matrix-producing breast tumours

Abstract

Most malignant MP breast tumours are variants of MBC. MP-MBC with predominant mesenchymal components behaves similar to ductal carcinomas and although data on their response to systemic therapy is limited, there is no evidence that they should be managed differently from other forms of triple negative breast cancer.

Extraskeletal osteosarcoma: A European Musculoskeletal Oncology Society study on 266 patients

“…These must be distinguished from matrix-producing epithelial breast carcinomas. Recommended criteria for ESOS of the breast include absence of an epithelial component and presence of malignant osteoid [15,16]. Histologically ESOS presents similar characteristics to those of skeletal osteosarcoma with a differing proportion of osteoid and cartilaginous and fibrous tissue [13].…”

Matrix-Producing Carcinoma of the Breast: Case Report

“…In the study of Wargotz and Norris, the clinical outcome of MPC was reported to be similar to that of a matched control group of patients with invasive ductal carcinoma (3). Similarly, Rakha et al (6) showed prognosis comparable to that of grade-and hormone receptor-matched ductal carcinoma and slightly better than other that of subtypes of metaplastic breast carcinoma in their large multi-institutional series of malignant matrix-producing breast tumors. However, Downs-Kelly et al (8) reported aggressive behavior in terms of increased locoregional and distant tumor recurrence rates compared with invasive ductal carcinoma.…”

“…They also demonstrated desmosome-like intercellular junctional structures, tonofilaments, and actin filaments in carcinoma cells ultrastructurally (7). Because the majority of MPC cases reported in the literature showed triple -negative features [estrogen receptor (−), progesterone receptor (−), and Her2/neu (−)] and a basal-like phenotype (cytokeratin 5/6, cytokeratin 14, and epidermal growth factor receptor positivity) (5,6,8,9), systemic chemotherapy following surgery is the treatment of choice at present (6).…”

“…The existing literature support that the malignant cells in MPC originate from epithelial cells of the ductal or myoepithelial type (6, 7). Rakha et al (6) indicated that the majority of matrix-producing breast tumors were associated with epithelial cell features and therefore they should be treated with breast carcinoma-specific therapy instead of sarcoma-specific therapy. Kusafuka et al (7) demonstrated the epithelial cell origin of MPC by immunohistochemical and ultrastructural examinations in their case series.…”

“…There are some reports that show no prognostic difference between MPC and invasive breast carcinoma at the same stage (3,6). In the study of Wargotz and Norris, the clinical outcome of MPC was reported to be similar to that of a matched control group of patients with invasive ductal carcinoma (3).…”