Comparative analysis of PD-L1 expression and tumor-infiltrating lymphocytes in metaplastic breast carcinoma and gynecologic carcinosarcoma: A single-institution retrospective study.

Metaplastic breast carcinoma (MBC) and gynecologic carcinosarcoma (GCS) are rare, clinically aggressive cancers that demonstrate epithelial components and mesenchymal or sarcomatoid components. In this study, we assessed PD-L1 expression and tumor-infiltrating lymphocytes (TILs) in MBC and GCS. Overall, PD-L1 positivity using the SP142 clone was seen in 50 % of MBC and 51.9 % of GCS cases, with PD-L1 expression in tumor cells significantly higher in MBC cases (p = 0.034), and PD-L1 expression in immune cells similar in MBC and GCS cases. PD-L1 expression was significantly higher in epithelial components than in mesenchymal components in both MBC and GCS cases (p = 0.0005). TILs were low in the majority of MBC and GCS cases (≥ 10 %) and generally correlated with PD-L1 expression; however, many PD-L1 positive cases with low TILs were seen. PD-L1 expression using the 22C3 clone was additionally assessed, with positivity seen in 62.9 % of MBC cases and 30 % of GCS cases. Concordance between SP142 and 22C3 results was seen in 62.5 % of MBC cases and 80 % of GCS cases. Overall, our findings suggest that a subset of MBC and GCS cases may benefit from immune checkpoint inhibitor therapy. Our findings also illustrate unique aspects of PD-L1 expression patterns in these tumors which may harbor additional prognostic and therapeutic significance.

A Rare and Intriguing Case Report of Metaplastic Breast Carcinoma.

Metaplastic breast carcinoma (MBC) is a rare and aggressive subtype of breast cancer characterized by the presence of both epithelial and mesenchymal components within the tumor. Its clinical and radiological appearance is comparable to other types of breast cancer, but it grows rapidly. The diagnosis of metaplastic carcinoma is largely based on the epithelial origin of the cells confirmed by immunohistochemistry (IHC). Compared to invasive ductal carcinoma, metaplastic carcinoma has a worse overall survival rate. Any patient with a rapidly growing breast mass should be assessed with suspicion of sarcomatoid or metaplastic malignant neoplasm. We report this case due to its rarity and the complex nature of the disease.

Immunohistochemical and molecular profiles of heterogeneous components of metaplastic breast cancer: a squamous cell carcinomatous component was distinct from a spindle cell carcinomatous component.

Metaplastic breast carcinoma (MBC), a category of breast cancer, includes different histological types, which are occasionally mixed and heterogeneous. Considering the heterogeneity of cancer cells in a tumour mass has become highly significant, not only from a biological aspect but also for clinical management of recurrence. This study aimed to analyse the immunohistochemical and molecular profiles of each MBC component of a tumour mass. Twenty-five MBC tumours were histologically evaluated, and the most frequent MBC component (c) was squamous cell carcinoma (SCC), followed by spindle cell carcinoma (SpCC). A total of 69 components of MBC and non-MBC in formalin-fixed paraffin-embedded sections were examined for 7 markers by immunohistochemistry. SCC(c) were significantly PTEN negative and CK14 positive, and SpCC(c) were significantly E-cadherin negative and vimentin positive. Multivariate analyses revealed that immunohistochemical profiles of normal/intraductal (IC)(c), no special type (NST)(c), and MBC(c) differed; moreover, SCC(c) and SpCC(c) were distinctly grouped. PTEN gene mutation was detected only in SCC(c) (2/7), but not in SpCC(c). Next-generation sequence analyses for 2 cases with tumours containing SCC(c) demonstrated that PTEN gene mutation increased progressively from IC(c) to NST(c) to SCC(c). In conclusion, the immunohistochemical and molecular profiles of the SCC(c) of MBC are distinct from those of the SpCC(c).

Translational Aspects in Metaplastic Breast Carcinoma.

Breast cancer is the most common cancer among women. Metaplastic breast carcinoma (MpBC) is a rare, heterogeneous group of invasive breast carcinomas, which are classified as predominantly triple-negative breast carcinomas (TNBCs; HR-negative/HER2-negative). Histologically, MpBC is classified into six subtypes. Two of these are considered low-grade and the others are high-grade. MpBCs seem to be more aggressive, less responsive to neoadjuvant chemotherapy, and have higher rates of chemoresistance than other TNBCs. MpBCs have a lower survival rate than expected for TNBCs. MpBC treatment represents a challenge, leading to a thorough exploration of the tumor immune microenvironment, which has recently opened the possibility of new therapeutic strategies. The epithelial-mesenchymal transition in MpBC is characterized by the loss of intercellular adhesion, downregulation of epithelial markers, underexpression of genes with biological epithelial functions, upregulation of mesenchymal markers, overexpression of genes with biological mesenchymal functions, acquisition of fibroblast-like (spindle) morphology, cytoskeleton reorganization, increased motility, invasiveness, and metastatic capabilities. This article reviews and summarizes the current knowledge and translational aspects of MpBC.

A Unique Surgical Case of Mixed Metaplastic Breast Carcinoma With Heterologous Mesenchymal Differentiation and Conventional Adenocarcinomatous Elements.

Metaplastic breast carcinoma (MBC) is very rare among all invasive breast carcinomas, accounting for less than 1.0% of them. MBCs are classified into five subtypes, including mixed MBC - where the mix might be multiple metaplastic elements or a mixture of epithelial and mesenchymal elements. Overall survival for mixed MBC tends to correlate with a significantly worse outcome. Therefore, an early accurate diagnosis and surgical treatment for mixed MBCs must allow for an improved quality of life and better prognosis. However, there have not been many recently published papers describing the detailed cytological features of mixed MBCs on fine-needle aspiration (FNA) specimens. A 60-year-old female presented with a history of a hard breast mass on the left lateral side, showing an ill-defined and marginally enhanced tumor nodule on magnetic resonance imaging. The cytologic specimens of FNA contained a large number of three-dimensional, cohesive and sheet-like clusters, or non-cohesive single cells, of highly atypical spindled sarcomatoid to oval epithelioid cells having hyperchromatic pleomorphic nuclei and mitotic figures, in a necrotic and hemorrhagic background. A small amount of osteoid matrix-like substance was rarely seen, associated with a very small number of osteoclast-like giant cells. We first interpreted it as an invasive breast carcinoma of high grade. A mastectomy was performed, and a gross examination of the neoplasm revealed a hemorrhagic solid tumor lesion with a gray-whitish cut surface, measuring approximately 35 × 24 × 21 mm in diameter. On a microscopic examination, the tumor was predominantly composed of the proliferation of highly atypical oval to spindled cells predominantly in a sarcomatous growth fashion with focal production of chondroid and osteoid matrix, peripherally coexisted with a smaller volume of conventional invasive breast carcinoma. Immunohistochemistry showed that the sarcomatous tumor cells were specifically positive for vimentin, α-smooth muscle actin, or epithelial membrane antigen. Therefore, we finally made a diagnosis of invasive mixed MBC with heterologous mesenchymal differentiation and conventional adenocarcinomatous elements. To the best of our knowledge, this would most recently be the first case report of mixed MBC with heterologous mesenchymal differentiation and conventional adenocarcinomatous elements, with a focus on its FNA cytomorphologic findings. We should be aware that owing to its characteristic cytological features, cytopathologists might be able to make a correct diagnosis of MBC, based on multiple and adequate samplings.

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

Background: The rarity of metaplastic breast carcinoma (MBC) has resulted in limited sonographic data. Given the inferior prognosis of MBC compared to invasive ductal carcinoma (IDC), accurate preoperative differentiation between the two is imperative for effective treatment planning and prognostic prediction. The objective of this study was to assess the diagnostic accuracy of MBC and differentiate it from IDC by analyzing sonographic and clinicopathologic features. Methods: In this retrospective cohort study, 197 women comprising 200 IDC lesions were enrolled between January 2012 and December 2021 and 20 women comprising 20 pure MBC lesions were enrolled between January 2019 and December 2019. A comparison was made between the sonographic and clinicopathologic characteristics of MBC and IDC. Results: The results indicated that patients with MBC had a higher proportion of tumor grade 3 (95.0% vs. 32.5%; P<0.001), high Ki-67 expression (100.0% vs. 75.0%; P<0.001), and the triple-negative subtype (90.0% vs. 13.0%; P<0.001) as compared to those with IDC. On ultrasound (US) findings, MBC lesions tended to have a larger size (≥5 cm: 45.0% vs. 1.5%; P<0.001), regular shape (45.0% vs. 1.5%, P<0.001), circumscribed margin (40.0% vs. 0.5%, P<0.001), a complex cystic and solid echo pattern (50.0% vs. 3.5%; P<0.001), and posterior acoustic enhancement (95.0% vs. 14.5%; P<0.001). Additionally, MBC was more likely to be misinterpreted as a benign lesion by sonographers than was IDC (30.0% vs. 4.5%; P<0.001). Multilayer perceptron analysis revealed posterior acoustic enhancement, circumscribed margins, and size as distinguishing factors between these two tumor types. The estimated rates of local recurrence, distant metastasis, and 5-year overall survival in 19 cases with MBC were found to be 10.5%, 31.6%, and 65.0%, respectively. Conclusions: MBC typically presents as a large breast mass with more benign US features in older women, findings which may facilitate its accurate diagnosis and differentiation from other breast masses.

Compartmental Syndecan-1 (CD138) expression as a novel prognostic marker in triple-negative metaplastic breast cancer.

BACKGROUND: Metaplastic breast cancer (MpBC) is rare, aggressive, and mostly triple-negative (TN) subtype of BC. We aimed to investigate the potential prognostic significance of Syndecan-1 (SDC1/CD138) expression in this unique tumor. METHODS: Archived charts of 50 TNBC patients [21 MpBC and 29 invasive ductal carcinoma (IDC)] were retrospectively evaluated. Corresponding paraffin blocks were used for immunohistochemical (IHC) staining of SDC1. Compartmental (epithelial membranous, stromal, and cytoplasmic) staining scores were expressed in quartiles (Q) and correlated with disease-free survival (DFS) and overall survival (OS). RESULTS: The median follow-up period was 54.6 months (range: 2.2-112.7). MpBC patients showed significantly worse DFS and OS than IDC (p = 0.007 and 0.004, respectively). MpBC demonstrated significantly higher Q4 stromal and membranous SDC1 compared to IDC (p = 0.016 and 0.021, respectively), whereas IDC exhibited significantly higher cytoplasmic Q4 SDC1 than MpBC (p = 0.015). Stromal Q4 SDC1 expression was found to be an independent factor associated with MpBC relative to IDC (OR: 6.7, 95% CI: 1.24-36.90; p = 0.028). Stromal Q4 SDC1 expression was also an independent prognostic parameter for worse DFS and OS compared to Q1-3 in the whole cohort (HR: 4.2, 95% CI: 1.6-10.5; p = 0.003 and HR: 5.8; 95% CI: 2.2-15.3; p < 0.001, respectively). In MpBC, cytoplasmic Q1-3 SDC1 expression was an independent prognostic indicator for worse OS compared with their IDC counterparts (HR: 2.837, 95% CI: 1.048-7.682; p = 0.04). CONCLUSION: This study suggests, for the first time, that differential expression and localization of SDC1 may contribute to the pathogenesis and prognosis of TN-MpBC. Therefore, targeting SDC1 (CD138) could emerge as a novel therapeutic approach for this devastating disease.

Bioinformatics analysis of human kallikrein 5 (KLK5) expression in metaplastic triple-negative breast cancer.

Background: Metaplastic breast carcinoma (MBC) is a rare breast cancer subtype; most cases are triple-negative breast cancers (TNBCs) and are poorly responsive to conventional systemic therapy. Few potential diagnostic and prognostic markers for distinguishing between metaplastic TNBC and nonmetaplastic TNBC have been discovered. We performed bioinformatic analysis to explore the underlying mechanism by which metaplastic TNBC differs from nonmetaplastic TNBC and provides potential pathogenic genes of metaplastic TNBC. Methods: Differentially expressed genes (DEGs) in metaplastic tumors and nonmetaplastic tumors from TNBC patients were screened using GSE165407. The GSE76275 data set and The Cancer Genome Atlas (TCGA) database were used to screen DEGs in TNBC and non-TNBC. Metascape and DAVID were used for the Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis and Gene Ontology (GO) analysis of DEGs. Online databases, including UALCAN, GEPIA, HPA, Breast Cancer Gene-Expression Miner, and quantitative PCR and western blot, were used to examine KLK5 messenger RNA and protein expression in breast cancer. Analysis of KLK5­associated genes was performed with TCGA data, and the LinkedOmics database was used to detect the genes co-expressed with KLK5. STRING (Search Tool for the Retrieval of Interacting Genes) and Cytoscape were used to screen for hub genes. Kaplan­Meier plotter was used for survival analysis. Results: KLK5 was identified among the DEGs in nonmetaplastic TNBC and metaplastic TNBC. The KLK5 gene was overexpressed in nonmetaplastic TNBC but downregulated in metaplastic TNBC. KEGG and GO analyses revealed that epithelial-to-mesenchymal transition was a pathogenic mechanism in metaplastic TNBC and an important pathway by which KLK5 and its associated genes DSG1 and DSG3 influence metaplastic TNBC progression. Prognosis analysis showed that only low expression of KLK5 in metaplastic TNBC had clinical significance. Conclusion: Our research indicated that KLK5 may be a pivotal molecule with a key role in the mechanism of tumorigenesis in metaplastic TNBC.

Evaluation of immune density, PD-L1, and CXCR4 expressions in metaplastic breast carcinoma to predict potential immunotherapy benefit.

Metaplastic breast carcinoma (MBC) -rare but fatal subtype of invasive breast carcinomas- provides limited benefit from conventional triple-negative breast carcinoma chemotherapy. We aimed to determine the immune density of this tumor and to evaluate of programmed death-ligand 1 (PD-L1) and chemokine receptor type 4 (CXCR4) expressions to determine whether it would benefit from immunotherapy. Clinicopathological characteristics of 85 patients diagnosed as MBC between 1997 and 2017 were retrospectively assessed. We evaluated the immunohistochemical expression of PD-L1 and CXCR4, and the extent of tumour infiltrating lymphocytes (TILs), with survival data. TILs groups were statistically significantly associated with lymph node status, histological subtype, squamous component, local recurrence and/or systemic metastasis, and disease-related deaths (p < 0.05). PD-L1 positivity in immune cells (ICs) has a statistically significant relationship with the presence of squamous component (p = 0.011) and HER2 positivity (p = 0.031). PD-L1 positivity in tumor cells (TCs) was found to be significantly more frequent in high-TILs density (p = 0.003). PD-L1 combined positive score was significantly associated with the tumors containing high-TILs density (p = 0.012) and squamous component (p = 0.035). Disease-free and disease-specific survival rates were found to be longer for the cases displaying PD-L1 positivity in ICs; and also PD-L1 positivity in ICs was found to be an independent prognostic factor. When the expression of CXCR4 was compared with clinicopathological and survival parameters, no statistically significant association was found (p > 0.05). Based on the results of this retrospective study, PD-L1 and TILs appear to be prognostic. This study provides rationale for further studies to determine whether a subset of patients with metaplastic breast cancer could derive a meaningful benefit from immune-targeting therapies.

Epithelial to mesenchymal transition (EMT) in metaplastic breast cancer and phyllodes breast tumors.

Epithelial-mesenchymal transition (EMT), a transdifferentiation program whereby epithelial cells acquire mesenchymal phenotype, is essential during embryonic development. EMT has also been implicated in cancer progression by conferring migratory and metastatic potential, as well as cell plasticity and stem cell like traits, to cancer cells. Metaplastic breast carcinoma (MBC) is a rare aggressive type of breast cancer characterized by the presence of heterologous elements, typically by the existence of epithelial and mesenchymal components. Phyllodes tumors (PTs) are uncommon fibroepithelial neoplasms consisting of epithelial and mesenchymal elements. Although various hypotheses have been proposed on the pathogenesis of these biphasic tumors, there is growing evidence supporting the theory that PTs and MBC could both correlate with cancer related EMT. This review summarizes the existing literature on the emerging role of EMT in the pathogenesis of MBC and PTs. Both malignant PTs and MBC are characterized by poor prognosis. Therefore, several anti-EMT targeting strategies such as blocking upstream signaling pathways, targeting the molecular drivers of EMT and targeting mesenchymal cells and the extracellular matrix, could potentially represent a promising therapeutic approach for patients suffering from these aggressive neoplasms.

Cytologic analysis of metaplastic breast carcinoma: Review of 66 cases diagnosed at the Institut Curie.

OBJECTIVES: Cytology reports of metaplastic breast carcinoma (MBC) are rare and limited to short series and simple case reports. To adapt cytology diagnostic criteria to the most recent fifth edition of the World Health Organization Classification of Breast Tumours from 2019, we have reviewed our series from the files of the Institut Curie. METHODS: A cohort of 66 female patients investigated by cytology with corresponding histologic diagnosis of MBC was identified. Eight cytologic characteristics were analyzed: cellularity, adenocarcinoma cells, squamous cells, spindle cells, giant cells, cytonuclear atypia, necrosis, and osseous/chondroid matrix and compared with histology. RESULTS: Cytologic diagnoses were malignant in 58 (88%) cases (of which 29 cases were typed cytologically as MBC), suspicious in 6 (9%) cases, and nondiagnostic in 2 (3%) cases. None of the cytologic examinations was a benign diagnosis. Low-grade adenosquamous carcinoma and fibromatosis-like metaplastic carcinoma exhibited a low degree of cellular atypia. Fibromatosis-like metaplastic carcinoma and spindle cell carcinoma (SpCC) presented spindle cells, while SpCC also demonstrated varying degrees of atypia, the presence of giant cells, and necrosis. Squamous cell carcinoma was characterized by the presence of squamous cells, and metaplastic carcinoma with osseous/chondroid differentiation displayed an osseous/chondroid matrix. CONCLUSIONS: Fine-needle aspiration holds considerable potential as a valid, independent, and complementary approach to histologic examination of MBC.

Multimodal Imaging Features and Prognosis of Metaplastic Breast Carcinoma.

RATIONALE AND OBJECTIVES: Metaplastic breast carcinoma (MBC) is an infrequent malignancy with an unfavorable prognosis, and there is a paucity of research on the multimodal imaging features of MBC. This study aimed to provide a comprehensive analysis of the multimodal imaging features, clinicopathological characteristics, and prognosis of MBC. MATERIALS AND METHODS: A total of 36 patients with histologically confirmed MBC from 2012 to 2021 were included in the study. We analyzed the pre-treatment multimodal imaging features, including mammography, ultrasonography (US), and magnetic resonance imaging (MRI), as well as clinicopathology and prognosis of MBC. Follow-up data included local recurrence, distant metastasis, and overall survival (OS) rate. RESULTS: MBC patients had a median age of 51 years at diagnosis. The most common histologic subtype was squamous cell carcinoma, with 86.1% of MBC being histological grade 3 and triple negative. The most common mammographic findings were irregular shape, non-calcification, and high density. The predominant US findings included irregular shape, parallel orientation, posterior acoustic enhancement, and hypoecho. On MRI, most masses exhibited irregular shape, spiculate margin, heterogeneous enhancement, Type II time intensity curve, and diffusion restriction on diffusion weighted images determined by apparent diffusion coefficient. According to breast imaging reporting and data system, mammography suggested malignancy in 50% of cases, US indicated a moderate to high suspicion of malignancy in 77.8% of cases, MRI revealed malignancy in all cases. At a median follow-up time of 48 months (range, 8-122 months) for 35 MBC patients, the local recurrence, distant metastasis, and OS rates were 11.4%, 28.6%, and 67.4%, respectively. CONCLUSION: The benign features of MBC on mammography and US may cause misinterpretation. However, the inclusion of malignant features observed on MRI can improve diagnostic accuracy.

Metaplastic Carcinoma of the Axillary Breast With Heterologous Mesenchymal (Chondroid) Differentiation: A Difficult Case and Literature Review.

Metaplastic breast carcinoma is an invasive carcinoma with a high differentiation rate of the neoplastic epithelium toward mesenchymal-like epithelium. It comprises of only less than 1% of all breast cancers. Although 80% to 90% of metaplastic breast carcinomas are triple-negative cancers, they usually have worse outcomes than other triple-negative breast cancers (TNBCs). Metaplastic carcinoma is also often refractory to cytotoxic chemotherapy. Here, we reported a case of a 61-year-old female patient, presenting with a solitary and pedunculated mass in the right axillary tail breast tissue, whose biopsy revealed metaplastic breast carcinoma with chondroid differentiation. She had failed neoadjuvant chemotherapy and immunotherapy. Although she received debulking surgery, the tumor regrew even faster before surgery. Despite receiving palliative chemotherapy, the patient died 11 weeks after surgery. This case draws attention to physicians that early recognition and surgery may be more beneficial than chemotherapy in combating metaplastic breast carcinoma.

Metaplastic carcinoma with osteosarcomatous differentiation in the breast: Case report.

Metaplastic breast carcinoma is rare and may present as a highly aggressive subtype of breast cancer. In this case report of metastatic metaplastic breast carcinoma with osteosarcomatous differentiation in a female patient previously treated for invasive ductal carcinoma, we describe the new presentation of a palpable mass with associated calcifications on imaging near the site of prior partial mastectomy. This article will detail the clinical presentation, imaging findings, histopathology, and clinical course following treatment of our case. Knowledge of the clinical and imaging presentation of this rare subtype, which can present with benign features on mammography and ultrasound, can facilitate timely diagnosis as treatment paradigms evolve.

Metaplastic breast carcinoma with osseous differentiation: A report of a rare case and literature review.

Metaplastic matrix-producing breast carcinoma is a type of metaplastic breast carcinoma (MBC), which is a rare malignancy, accounting for 0.2-1% of breast carcinomas. A 52-year-old female visited a hospital because of a palpable painless mass in the right breast and was diagnosed with Breast Imaging Reporting and Data System (BI-RADS) category 4A via ultrasound (US) with a suspected positive lymph node at the right axillary region. Excision of the breast mass was performed and histopathologically confirmed that it was MBC with osseous differentiation. No distant metastasis was revealed before a modified radical mastectomy; however, metastasis to a lymph node of the right axillary region was observed (1/22). She received six cycles of TEC scheme chemotherapy (docetaxel, epirubicin, and cyclophosphamide, 21 days) and 5 weeks of radiotherapy (48 Gy/25 f/5 days a week), but without any follow-up examinations since radiotherapy. Twenty-four months after surgery, distant metastases to lungs and liver were confirmed and died 3 months later. This case provides valuable information for clinicians on MBC and suggests that further examination or biopsy should be performed to US BI-RADS 4A masses before surgery. In addition, regular postoperative follow-up plays important roles in detecting metastases early and improving prognosis.

Metaplastic Breast Carcinoma in U.S. Population: Racial Disparities, Survival Benefit of Adjuvant Chemoradiation and Future Personalized Treatment with Genomic Landscape.

PURPOSE: In this population-based study, we aim to identify factors that are influential on the survival outcome in MBC and investigate novel molecular approaches in personalized disease management. METHODS: The data of this study were collected from the SEER database from 2000-2018. A total of 5315 cases were extracted from the database. The data were evaluated for demographics, tumor characteristics, metastasis, and treatment. Survival analysis was completed by using SAS software for multivariate analysis, univariate analysis, and non-parametric survival analysis. The molecular data with the most common mutations in MBC were extracted from the Catalogue of Somatic Mutations in Cancer (COSMIC) database. RESULTS: The mean age at the time of presentation was 63.1 with a standard deviation (SD) of 14.2 years. Most patients were White (77.3%) with 15.7% Black patients, 6.1% Asian or Pacific Islander, and 0.5% American Indian. Histologically, most of the reported tumors were grade III (74.4%); 37% of the cases were triple negative (ER-, PR- and HER2-), whereas the hormone status was unknown in 46% of the cases. Spread was localized in 67.3% of patients while 26.3% had regional spread and 6.3% had distant metastases. Most tumors were unilateral (99.9%) and between 20-50 mm in size (50.6%). The lungs were the most common site for distant metastasis at diagnosis (3.42%) followed by bone (1.94%), liver (0.98%), and brain (0.56%). A combination of surgery, chemotherapy, and radiation therapy was the most common treatment with a cause-specific survival rate of 78.1% (95% CI = 75.4-80.4). The overall survival rate at 5 years was 63.6% (95% confidence interval (CI) = 62.0-65.1) with a cause-specific survival of 71.1% (95% CI = 69.5-72.6). Cause-specific survival was found to be 63.2% (95% CI = 58.9-67.1) in Black patients as compared to 72.4% (95% CI = 70.1-74.1) in White patients. Black patients also presented with higher rates of grade III disease, distant metastasis, and larger tumor size. On multivariate analysis, age > 60, grade III+, metastasis, and tumor size > 50 mm were associated with worse survival. The most common mutations in MBC identified in COSMIC data were TP53, PIK3CA, LRP1B, PTEN, and KMT2C. CONCLUSION: Though rare, MBC is aggressive, with poor prognosis associated with high-grade tumors, metastasis, tumor size over 50 mm, and advanced age at the time of presentation. Overall, Black women had worse clinical outcomes. MBC is difficult to treat and carries a poor prognosis that affects various races disproportionately. Continued enhancement of treatment strategies to foster more individualized care as well as continued enrollment in clinical trials are needed to improve outcomes among patients with MBC.

Dynamic contrast-enhanced MRI and sequential CT findings of metaplastic breast carcinoma in neurofibromatosis type 1: A case report.

Metaplastic breast carcinoma in neurofibromatosis type 1 is extremely rare. There are few reports about dynamic contrast-enhanced MRI findings and sequential CT findings of metaplastic breast carcinoma in neurofibromatosis type 1. Herein, we report imaging findings, including dynamic contrast-enhanced MRI and sequential CT, of metaplastic breast carcinoma in an 82-year-old woman with neurofibromatosis type 1. Short tau inversion recovery image revealed an oval mass with a circumscribed margin that exhibited moderate intensity with partially hyperintense area inside, and T1-weighted imaging revealed a spotty hyperintense area. The solid component of the mass showed heterogeneous enhancement and the time-intensity curve had a fast/washout pattern with restricted diffusion. In addition, multiple neurofibromas were observed. Sequential CT revealed that the diameter of the mass doubled in 3 months without apparent lymph node metastasis. Because detection of metaplastic breast carcinoma in neurofibromatosis type 1 tends to be delayed due to multiple neurofibromas, characteristic MRI findings suggestive of metaplastic breast carcinoma and sequential CT findings are important for early treatment of metaplastic breast carcinoma in patients with neurofibromatosis type 1.

Carcinosarcoma: A Rare and Aggressive Breast Tumor in a Young Lady.

Carcinosarcoma of the breast is a subtype of metaplastic breast carcinoma characterized by differentiation of the neoplastic epithelium toward mesenchymal-looking elements. It is a highly aggressive rare subtype of invasive breast neoplasm that exhibits a distinct histologic entity. Only a limited number of reports related to this type of disease have been reported. Here, we present a case of breast carcinosarcoma in a lady in her early 20s, which is relatively young among all cases published. It was challenging to achieve diagnosis preoperatively with histopathological evaluation of the ultrasound-guided tru-cut biopsy sample. With no evidence of distant metastasis clinically and radiologically, a surgical option was opted for. Left mastectomy and left chest wall reconstruction with deep inferior epigastric artery free flap were performed. Post-excision specimen was confirmed to be carcinosarcoma.

Metaplastic breast carcinoma producing prominent basal lamina with neuroendocrine differentiation: A case report.

Metaplastic breast carcinoma (MBC) is a heterogeneous group of invasive breast carcinomas (IBCs) characterized by the differentiation of the neoplastic epithelium toward squamous cells and/or mesenchymal-appearing elements. The present study describes the case of a 42-year-old woman who underwent a mastectomy and sentinel lymph node biopsy for two tumors in their left breast. One of the resected tumors was diagnosed as MBC with neuroendocrine (NE) differentiation and the other was diagnosed as IBC of no special type. The MBC tumor contained a matrix composed of basal lamina with a focal area of myxoid matrix and squamoid differentiation. To the best of our knowledge, the present study is the first report of MBC producing prominent basal lamina. The patient has remained alive and well for >10 years without recurrence, and has been treated with oral and injected anticancer drugs.