Radiologic Findings of a Rare Subtype of Invasive Breast Cancer with Poor Prognosis: Metaplastic Carcinoma of the Breast

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.

Nomogram for the prediction of triple-negative breast cancer histological heterogeneity based on multiparameter MRI features: A preliminary study including metaplastic carcinoma and non- metaplastic carcinoma

Objectives

Triple-negative breast cancer (TNBC) is a heterogeneous disease, and different histological subtypes of TNBC have different clinicopathological features and prognoses. Therefore, this study aimed to establish a nomogram model to predict the histological heterogeneity of TNBC: including Metaplastic Carcinoma (MC) and Non-Metaplastic Carcinoma (NMC).

Methods

We evaluated 117 patients who had pathologically confirmed TNBC between November 2016 and December 2020 and collected preoperative multiparameter MRI and clinicopathological data. The patients were randomly assigned to a training set and a validation set at a ratio of 3:1. Based on logistic regression analysis, we established a nomogram model to predict the histopathological subtype of TNBC. Nomogram performance was assessed with the area under the receiver operating characteristic curve (AUC), calibration curve and decision curve. According to the follow-up information, disease-free survival (DFS) survival curve was estimated using the Kaplan-Meier product-limit method.

Results

Of the 117 TNBC patients, 29 patients had TNBC-MC (age range, 29–65 years; median age, 48.0 years), and 88 had TNBC-NMC (age range, 28–88 years; median age, 44.5 years). Multivariate logistic regression analysis demonstrated that lesion type (p = 0.001) and internal enhancement pattern (p = 0.001) were significantly predictive of TNBC subtypes in the training set. The nomogram incorporating these variables showed excellent discrimination power with an AUC of 0.849 (95% CI: 0.750−0.949) in the training set and 0.819 (95% CI: 0.693−0.946) in the validation set. Up to the cutoff date for this analysis, a total of 66 patients were enrolled in the prognostic analysis. Six of 14 TNBC-MC patients experienced recurrence, while 7 of 52 TNBC-NMC patients experienced recurrence. The DFS of the two subtypes was significantly different (p=0.035).

Conclusions

In conclusion, we developed a nomogram consisting of lesion type and internal enhancement pattern, which showed good discrimination ability in predicting TNBC-MC and TNBC-NMC.

Spindle Cell Metaplastic Breast Carcinoma

INTRODUCTION

Metaplastic breast carcinoma is an uncommon malignancy that constitutes < 5% of all breast cancers. There are 5 subtypes which are spindle cell, squamous cell, carcinosarcoma, matrix-producing and metaplastic with osteoclastic giant cells. Spindle cell carcinoma represents approximately <0.3% of invasive breast carcinomas. It is typically a triple-negative cancer with distinct pathological characteristics, but relatively a non-conclusive imaging findings.

CASE REPORT

An elderly lady presented with an enlarging painful left breast lump for 1 year. Palpable left breast lump noted on clinical examination. Mammography demonstrated a high density, oval lesion with a partially indistinct margin. Corresponding ultrasound showed a large irregular heterogeneous lesion with solid-cystic areas. Histopathology showed atypical spindle-shaped cells which stained positive for cytokeratins and negative for hormone and human epidermal growth factor receptors, which favours spindle cell metaplastic carcinoma. Left mastectomy and axillary dissection were performed, and the final diagnosis was consistent with metaplastic spindle cell carcinoma.

CONCLUSION

Spindle cell carcinoma of the breast is a rare aggressive histological type of carcinoma which may present with benign features on imaging. Tissue diagnosis is essential for prompt diagnosis with multidisciplinary team discussion to guide management and improve patient's outcome.

m6A-induced LINC00958 promotes breast cancer tumorigenesis via the miR-378a-3p/YY1 axis

Increasing evidence demonstrates that long noncoding RNAs (lncRNAs) play critical roles in human breast cancer (BC) tumorigenesis. However, the mechanisms by which lncRNA and N⁶-methyladenosine (m⁶A) regulate BC tumorigenesis are still unclear. In the present research, LINC00958 was markedly overexpressed in BC tissue and cells, and LINC00958 upregulation promoted the tumor progression of BC cells. Mechanistically, m⁶A methyltransferase-like 3 (METTL3) gave rise to the upregulation of LINC00958 by promoting its RNA transcript stability. Moreover, LINC00958 acted as a competitive endogenous RNA for miR-378a-3p to promote YY1. Overall, these data provide novel insight into how m⁶A-mediated LINC00958 regulates BC tumorigenesis.