Magnetic resonance imaging of metaplastic carcinoma of the breast: sonographic and pathologic correlation

Discrepancy between Tumor Size Assessed by Full-Field Digital Mammography or Ultrasonography (cT) and Pathology (pT) in a Multicenter Series of Breast Metaplastic Carcinoma Patients

Metaplastic breast cancer (BC-Mp) presents diagnostic and therapeutic complexities, with scant literature available. Correct assessment of tumor size by ultrasound (US) and full-field digital mammography (FFDM) is crucial for treatment planning.

METHODS

A retrospective cohort study was conducted on databases encompassing records of BC patients (2012-2022) at the National Research Institutes of Oncology (Warsaw, Gliwice and Krakow Branches). Inclusion criteria comprised confirmed diagnosis in postsurgical pathology reports with tumor size details (pT) and availability of tumor size from preoperative US and/or FFDM. Patients subjected to neoadjuvant systemic treatment were excluded. Demographics and clinicopathological data were gathered.

RESULTS

Forty-five females were included. A total of 86.7% were triple-negative. The median age was 66 years (range: 33-89). The median pT was 41.63 mm (6-130), and eight patients were N-positive. Median tumor size assessed by US and FFDM was 31.81 mm (9-100) and 34.14 mm (0-120), respectively. Neither technique demonstrated superiority (p > 0.05), but they both underestimated the tumor size (p = 0.002 for US and p = 0.018 for FFDM). Smaller tumors (pT1-2) were statistically more accurately assessed by any technique (p < 0.001). Only pT correlated with overall survival.

CONCLUSION

The risk of underestimation in tumor size assessment with US and FFDM has to be taken into consideration while planning surgical procedures for BC-Mp.

Metaplastic breast carcinoma: an overview of the radio-pathologic features in retrospective cohort tertiary hospital

Background

Metaplastic breast carcinoma (MBC) is a rare type of breast carcinoma. It accounts for 0.2–1% of all invasive breast carcinoma. The aim of this study is to investigate the radiological features of this tumor and correlate them with the pathological findings.

Results

Of the 22 patients with pathology-proven metaplastic cancers, 18 patients  (81.82%) presented with a palpable mass. The majority of the mammogram findings were masses with irregular shapes (n = 12, 63.16%) and indistinct margins (n = 11, 57.89%). Similarly, the majority of the ultrasound studies showed masses with irregular shapes (n = 16, 72.73%) and indistinct margins (n = 8, 36.36%). Most of the echopatterns were complex or with heterogeneous textures, each presented in eight cases (36.36%). More than half of the cases had a posterior acoustic enhancement (n = 12, 54.55%). Most of the cases tested negative for estrogen receptors, progesterone receptors and HER2 protein, and they were high-grade tumors with a high proliferative index (Ki-67%) of > 15%.

Conclusion

MBC is a rare and distinct aggressive breast cancer with no definite characteristic imaging compared to other breast cancer. It shows a mass with irregular shape and indistinct margins in both mammogram and ultrasound. Additionally, it reveals posterior acoustic enhancement and rarely contains microcalcifications. The correlation with the pathological findings is crucial for the diagnosis and subsequent appropriate treatment.

Imaging Findings of Metaplastic Breast Carcinoma with Chondroid Differentiation: A Case Reports

Metaplastic carcinoma of the breast is a heterogeneous group of neoplasms with mixed epithelial and mesenchymal differentiation. Metaplastic carcinoma of the breast is a rare and aggressive malignancy, with high recurrence and metastasis. Metaplastic carcinoma with chondroid differentiation is an uncommon subtype that tends to have a relatively good prognosis than that of other subtypes. We report the imaging features of three cases of pathologically proven metaplastic carcinoma with chondroid differentiation as follows: a high-density mass with amorphous or coarse heterogeneous calcifications on mammography; a microlobulated or partially indistinct, complex cystic, and solid mass on sonography; and a relatively circumscribed or partially indistinct, irregular mass with heterogeneous T2 high-signal intensity and heterogeneous or rim enhancement with initial fast enhance ment and delayed washout on MRI.

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.

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

BACKGROUND AND OBJECTIVES

The purpose of this study was to evaluate the mammographic, sonographic and MRI findings of metaplastic breast carcinoma.

METHODS

In this retrospective review study, we analyzed the medical files of 9600 patients who were treated for invasive breast cancers. Clinical information, histopathologic and radiologic findings of 65 patients were included in this study. All existing radiologic images and medical reports were reviewed retrospectively. Thirty-three patients had MG, 58 patients had US and 7 patients had MRI imaging results.

RESULTS

Mammographically, the most frequent presentations of MPBC were round shape, microlobulated margin and high density masses. Calcifications with or without masses were not a frequent finding. The most common sonographic findings were round shape, partially indistinct angular margin, hypoechoic and heterogeneous echo patterns and no posterior feature masses. All lesions were presented as masses rather than non-mass enhancements on magnetic resonance imaging. Features of masses had more malignant feature on MRI than other modalities in all 7 patients.

CONCLUSION

Metaplastic breast carcinoma is one of the rarest poorly differentiated invasive breast carcinomas. Interestingly, these aggressive tumors demonstrate benign or moderately malign features on imaging methods. This appearance of MPBC can cause it to be misdiagnosed as a benign breast lesion especially in young women. MPBC should be kept in mind in the differential diagnosis of large palpable breast masses. Therefore, follow-up at short intervals and/or multimodality imaging studies which include breast MRI are important for the diagnosis of MPBC.

Multimodality Imaging Findings of Metaplastic Breast Carcinomas: A Report of Five Cases

Metaplastic carcinoma is a rare subtype of breast cancer that comprises histologically diverse malignancies. Metaplastic carcinoma tends to have an aggressive clinical presentation, high metastatic potential, and more chances of local recurrence, as compared with intraductal carcinoma. Although many clinical and pathologic finding have been reported, to our knowledge, there are few reports of imaging findings for this type of tumor.In this study, we reviewed data of 5 patients with histopathologically proven metaplastic breast carcinoma. Multimodality imaging findings including those from mammography, ultrasonography, magnetic resonance imaging, and positron emission tomography-computed tomography were recorded.The results indicated that metaplastic carcinomas tend to show more benign imaging features such as round or oval shape with circumscribed margins and less axillary lymph node metastasis compared with invasive ductal carcinoma. High signal intensity on T2-weighted magnetic resonance imaging due to its cystic or necrotic component may be useful for diagnosis of metaplastic carcinoma.

Post-traumatic rapidly enlarging mucinous carcinoma of the breast with intratumoural haemorrhage: MRI appearances with pathological correlation

Pure mucinous carcinoma of the breast is a histological type of invasive carcinoma and generally shows a slow growth pattern. Rapid growth and intratumoural haemorrhage are rare and there have been no reports presenting such a clinical course and associated radiographic findings. We report a case with atypical rapidly enlarging mucinous carcinoma of the breast after trauma, in which MRI closely reflected the histopathological background and was thought to be useful for differential diagnosis from other highly malignant breast tumours.

Imaging Features of Metaplastic Carcinoma with Chondroid Differentiation of the Breast

OBJECTIVE

The purpose of this study was to evaluate the imaging features--including the mammographic, sonographic, MRI, and bone scintigraphic findings--in 12 patients with metaplastic carcinoma with chondroid differentiation of the breast and to correlate the imaging findings with the pathologic features.

CONCLUSION

Metaplastic carcinoma with chondroid differentiation of the breast manifests as a palpable mass and should be included in the differential diagnosis of a large indistinct highdensity mass with amorphous or coarse calcifications on mammography and a relatively circumscribed complex echoic mass with posterior enhancement on sonography. A relatively circumscribed mass with a nonenhancing T2 intermediate- to high-signal-intensity internal component on MRI and an area of intense uptake of 99mTc methylene diphosphonate (MDP) on bone scintigraphy might be useful in suggesting the diagnosis of metaplastic carcinoma with chondroid differentiation.

[Metaplastic carcinoma of the breast: magnetic resonance and radiophatologic correlation]

OBJECTIVES

To review our radiological experience in metaplastic carcinoma together with the clinical and histopathologic findings.

METHODS AND MATERIALS

Eight cases of histologically confirmed metaplastic carcinoma of breast were reviewed. Imaging findings from US, mammography and MRI, and immunohistochemistry results from preoperative biopsy were assessed. Conventional prognostic factors, chondral differentiation markers, striated and straight muscle markers, neural markers, cytokeratin, vimentin and intermediate filaments were determined.

RESULTS

Eight patients aged ranged from 41-72 years. Metaplastic carcinoma presented as a palpable nodule in five cases, as a nipple retraction in ones case, and was discovered as an incidental mammographic finding in two. Mammographic appearance was a round, high-density nodule, measuring 10-50 mm, with variable margins in seven patients. One had architectural distortion. In three there were calcifications. Skin and nipple retraction appeared in one. On sonographic examination nodules were ill defined and showed low heterogeneous echogenicity. On MRI, T2-weighted images showed a relatively well-defined mass with high signal intensity. In the dynamic study, all showed contrast uptake, with signal-time intensity curves similar to those of infiltrating carcinoma of the breast. Histopathologic study found one squamous-cell, one sarcomatous, three chondroid, one giant-cell, one spindle-cell, and one acantholytic carcinoma, all of which were of high histologic grade.

CONCLUSIONS

Metaplastic carcinoma should be included in the differential diagnosis of a nodule presenting with high density and variable margins on mammography, low heterogeneous echogenicity and ill defined margins on sonography, and hyperintense at T2 with malignant enhancement at MR. Immunohistochemical assessment is mandatory for the final diagnosis. The radiologist can suggest this particular subtype of tumour.