Differentiation between Phyllodes Tumors and Fibroadenomas Based on Mammographic Sonographic and MRI Features

Differentiation Between G1 and G2/G3 Phyllodes Tumors of Breast Using Mammography and Mammographic Texture Analysis

Purpose: To determine the potential of mammography (MG) and mammographic texture analysis in differentiation between Grade 1 (G1) and Grade 2/ Grade 3 (G2/G3) phyllodes tumors (PTs) of breast.

Materials and methods: A total of 80 female patients with histologically proven PTs were included in this study. 45 subjects who underwent pretreatment MG from 2010 to 2017 were retrospectively analyzed, including 14 PTs G1 and 31 PTs G2/G3. Tumor size, shape, margin, density, homogeneity, presence of fat, or calcifications, a halo-sign as well as some indirect manifestations were evaluated. Texture analysis features were performed using commercial software. Receiver operating characteristic curve (ROC) was used to determine the sensitivity and specificity of prediction.

Results: G2/G3 PTs showed a larger size (>4.0 cm) compared to PTs G1 (64.52 vs. 28.57%, p = 0.025). A strong lobulation or multinodular confluent was more common in G2/G3 PTs compared to PTs G1 (64.52 vs. 14.29%, p = 0.004). Significant differences were also observed in tumors' growth speed and clinical manifestations (p = 0.007, 0.022, respectively). Ten texture features showed significant differences between the two groups (p < 0.05), Correlation_AllDirection_offset7_SD and ClusterProminence_AllDirection_offset7_SD were independent risk factors. The area under the curve (AUC) of imaging-based diagnosis, texture analysis-based diagnosis and the combination of the two approaches were 0.805, 0.730, and 0.843 (90.3% sensitivity and 85.7% specificity).

Conclusions: Texture analysis has great potential to improve the diagnostic efficacy of MG in differentiating PTs G1 from PTs G2/G3.

Magnetic resonance imaging of fibroadenoma-like lesions and correlation with Breast Imaging-Reporting and Data System and Kaiser scoring system

Background

Multiple breast lesions resembling fibroadenomas are a common imaging finding in patients presenting to the mammography unit at Dr George Mukhari Academic Hospital in the North-West district of Tshwane, South Africa. Patients often present with multiple lesions, up to 20 lesions per breast. These lesions often have atypical features on ultrasound and/or a clinical history of growth is commonly given. Phyllodes tumours may be indistinguishable from fibroadenomas and breast cancers may on occasion present with benign features, which can lead to misdiagnosis. Breast magnetic resonance imaging (bMRI) evaluation of lesions resembling fibroadenomas may improve accurate assessment and identification of lesions requiring biopsy.

Objectives

To assess the reliability of bMRI to characterise lesions resembling fibroadenomas on ultrasound, using the Breast Imaging-Reporting and Data System (BI-RADS) and Kaiser scoring systems with histopathological correlation.

Method

A quantitative, prospective, investigative study was performed with a sample size of 100 breast lesions among a total of 35 patients at Dr George Mukhari Academic Hospital. Patients were recruited after a breast ultrasound investigation revealed lesions resembling fibroadenomas, but with an indication for ultrasound-guided biopsy, for example, very large size, atypical features on ultrasound or a history of recent growth. The bMRI was performed prior to the ultrasound-guided breast biopsies. Three investigators independently evaluated the bMRI and applied BI-RADS descriptors to each lesion. The Kaiser score was then calculated for each lesion. Statistics were calculated using Pearson’s and Spearman’s coefficients for inter-reader variability, kappa scores for BI-RADS and Kaiser score correlation with histology.

Results

Evaluation with bMRI, BI-RADS and the Kaiser scoring system showed statistically significant correlation with each other and with histopathology results for each lesion. There was statistically significant agreement among the investigators regarding the interpretation of the lesions and allocation of appropriate BI-RADS scores.

Conclusion

Multiple lesions resembling fibroadenomas can be evaluated with bMRI when multiple breast biopsies would not be feasible. With a good imaging protocol and technique, adequate interpretation skills by the radiologist and the use of the Kaiser scoring system, an accurate diagnosis can be achieved.

A large benign phyllodes tumour of the breast: A case report and literature review

•

Phyllodes is an uncommon tumour of the breast that should be considered in the middle age women with a rapidly enlarging breast mass.

•

There is no hallmark imaging characteristic of phyllodes tumour.

•

It is difficult to diagnose phyllodes based on a core biopsy due to the subjective nature of interpretation of the degree of stromal cellularity and degree of atypia.

•

Even if a phyllodes is diagnosed on core biopsy, an excision biopsy is always required to determine if it is a benign or malignant phyllodes tumour.

•

Complete systemic review of patient is important as in this case report, the patient’s malignant parotid tumour was diagnosed when she presented with her benign phyllodes tumour.

Introduction

Phyllodes tumours are uncommon fibroepithelial lesions that typically grow up to 4 cm in size but 10 cm tumours known as giant phyllodes tumours have been described. We present a case report of a 20 cm benign phyllodes tumour and a literature review.

Presentation of case

A 54 years old lady with an enlarging left breast mass measuring 20 cm of 6 months duration presented to our outpatient breast clinic. She also had an incidental right parotid lump. Core biopsy of the left breast mass returned as a cellular fibroepithelial lesion. A mastectomy and axillary lymph node sampling were done and skin cover was obtained from a split skin graft from the thigh. Final histology returned as a benign phyllodes tumour. Her post-operative recovery was uneventful.

Discussion

Phyllodes tumours are suspected in middle age women with rapidly enlarging painless breast masses. Though there are some suggestive features on ultrasound and MRI, the key to diagnosis is still histopathology. However, a pre-operative diagnosis may not always be possible as the interpretation of stromal cellularity and degree of atypia needed to differentiate cellular fibroadenoma from a phyllodes tumour is subjective. When a phyllodes tumour is suspected, adequate margins should be taken for optimal outcome.

Conclusion

Successful management of phyllodes tumour involves obtaining a pre-operative diagnosis via a core biopsy when possible and planning for adequate margins.

Validation of the Singapore nomogram for outcome prediction in breast phyllodes tumours in a large patient cohort

Aims

To validate the Singapore nomogram for outcome prediction in breast phyllodes tumours in a large cohort of Singaporean patients, as previous validation studies were conducted on small numbers of patients. We also investigate the association of fibroadenomas and phyllodes tumours within a subset of our cohort.

Methods

Histological parameters, surgical margin status and clinical follow-up data of 259 women diagnosed with phyllodes tumours were analysed. Patients with concurrent malignant or premalignant disease were excluded from the validation to minimise confounding influences. Biostatistics modelling was performed, and the concordance between predicted and observed survivals was calculated. The association between fibroadenomas and phyllodes tumours was quantified in a subset of the women.

Results

Phyllodes tumours with higher number of mitoses, stromal overgrowth and positive surgical margins were found to be associated with greater risk of clinical recurrence. Patients with a higher nomogram score had a significantly higher risk of developing relapse. Forty out of 78 (51.3%) of the subset of phyllodes cases reviewed showed either fibroadenoma-like areas within the phyllodes tumours or concurrent fibroadenomas in the ipsilateral or contralateral breast.

Conclusions

The Singapore nomogram is useful in predicting outcome in breast phyllodes tumours when applied to a large cohort of Singaporean women.

Combination of shear-wave elastography and color Doppler: Feasible method to avoid unnecessary breast excision of fibroepithelial lesions diagnosed by core needle biopsy

Background

We evaluated shear-wave elastography (SWE) and color Doppler ultrasonography (US) features for fibroepithelial lesions (FELs), and to evaluate their utility to differentiate fibroadenomas (FAs) and phyllodes tumors (PTs).

Methods

This retrospective study included 67 FELs pathologically confirmed (49 FAs, 18 PTs). B-mode US, SWE and color Doppler US were performed for each lesion. Mean elasticity (E_mean), maximum elasticity (E_max), and vascularity were determined by SWE and Doppler US. Diagnostic performances were calculated to differentiate FAs and PTs. Equivocal FELs diagnosed by core needle biopsy (CNB) were further analyzed.

Results

Median E_mean and E_max were significantly lower for FAs than PTs (E_mean, 15.7 vs. 66.7 kPa; E_max, 21.0 vs. 76.7 kPa, P<0.01). Low vascularity (0–1 vessel flow) on color Doppler US were more frequent in FAs than in PTs (P<0.01). SWE showed significantly higher specificities (E_mean >43.9 kPa, 89.8%; E_max >46.1 kPa, 79.6%) than B-mode US (42.9%) (P<0.01) for differentiating PTs from FAs. Other diagnostic values of SWE and overall diagnostic values of Doppler US were not significantly different from B-mode US (P>0.05). The combination of SWE and Doppler US with ‘E_mean>43.9 kPa or high vascularity (≥2 vessel flows)’ showed a higher area under the curve (0.786 vs. 0.687) and higher diagnostic values than B-mode US (sensitivity, 100 vs. 94.4%; specificity, 57.1 vs. 42.9%; positive predictive value, 46.2 vs. 37.8%; negative predictive value, 100 vs. 95.5%), without statistical significance (P>0.05). Of the 30 equivocal FELs, all lesions with ‘E_mean≤43.9 kPa and low vascularity (0–1 vessel flow)’ (23.3%, 7/30) were finally confirmed as FAs by excision.

Conclusion

FAs have a tendency to have less stiffness and lower vascularity than PTs. Combined SWE and color Doppler US may help patients with equivocal FELs diagnosed by CNB avoid unnecessary excision.