Imaging findings in phyllodes tumors of the breast

Coexistence of benign phyllodes tumor and invasive ductal cancer in the ipsilateral breast: A case report

INTRODUCTION AND IMPORTANCE

Phyllodes tumors (PTs) are rare breast neoplasms, with an incidence rate of <1 %. Further, the coexistence of PTs and carcinoma is also uncommon. In this report, we describe a rare case of the synchronous coexistence of a benign PT and invasive ductal carcinoma (IDC) of the ipsilateral breast.

CASE PRESENTATION

A 42-year-old woman presented with a 6-month history of a tumor in her right breast. Mammography and ultrasonography revealed a 9.0 cm breast lump, and core biopsy revealed a benign PT. A simple mastectomy of the right breast revealed IDC foci in the mammary area, close to the benign PT. Right axillary lymph node staging was performed by surgery. However, no lymph node metastasis was observed. Subsequently, appropriate adjuvant therapy was initiated. Currently, the patient is doing well.

CLINICAL DISCUSSION

Breast cancer may be located close to the PT of the ipsilateral breast and is difficult to detect preoperatively, especially in cases of large PTs. Early detection of the presence of a coexisting carcinoma is clinically important because it can alter patient management.

CONCLUSION

Careful assessment of the PT using additional breast imaging tools might help identify their coexistence with breast cancer in cases of difficult diagnosis of coexistent tumors using standard breast imaging tools such as mammography or ultrasound.

Malignant phyllodes tumour of the breast with early recurrence in a young patient

A young woman in her 20s was found to have a left breast malignant phyllodes tumour by ultrasound-guided core needle biopsy, after identifying a palpable lump. She then underwent lumpectomy excision with >1 cm gross margins; however, final pathology demonstrated <1 cm margins at the superior margin. She then underwent re-excision of superior and medial margins to ensure at least a 1 cm margin. Biopsy tract was not excised at initial or re-excision surgery. Approximately 6 weeks after completion lumpectomy, the patient noted a new palpable mass near the previous biopsy site and underwent punch biopsy. Final pathology of this new mass was concordant with early recurrence. The patient then underwent lumpectomy of the new mass along with excision of the overlying skin and biopsy tract with >1 cm margins.

Clinical and radiological evaluation of a phyllodes tumor of the breast: a case report

Phyllodes tumors (PTs) are rare breast tumors characterized by varying biological behavior and heterogeneous clinical findings. As a result, accurately diagnosing PTs preoperatively is challenging, often leading to misdiagnosis. A 49-year-old patient presented with a steadily growing right breast mass that had persisted over a 10-year period. Breast mammography and ultrasonography results indicated the presence of a PT. Following a lumpectomy, the patient was diagnosed with a borderline PT. However, nearly 1 year later, she was readmitted due to the recurrence of a palpable mass at the site. Consequently, 1 year and 8 months after the initial operation, she underwent thoracoscopic lobectomy to address solitary lung metastases. Subsequently, the patient experienced brain metastasis and massive hemorrhage 14 months later. Long-term follow-up was recommended. This case study presents an instance of borderline PT with clinical and imaging features that are crucial for guiding clinical operations and evaluating patient prognosis.

Distinguishing Fibroepithelial Lesions Requires Clinical, Imaging, and Pathology Correlation

Phyllodes tumor (PT) is a rare tumor that can present as benign, borderline, or malignant. These tumors arise from the breast stroma, similar to fibroadenomas. Phyllodes tumors and fibroadenomas often have overlapping features in both radiological imaging and pathologic analysis. As a result, these two lesions are often difficult to differentiate and require the correlation of multiple modalities, including clinical context, radiologic imaging, and histological evaluation. This article presents a case of a borderline phyllodes tumor in a 51-year-old female, with the inclusion of its radiologic and pathologic images and performed treatment. The goal of this article is to provide a review of the clinical presentation, diagnostic imaging and pathology features, treatment, and management of a phyllodes tumor and compare and contrast this against the more common fibroadenomas, in order to provide aid for differentiating these two breast lesions.

Giant breast phyllodes tumor with silent thromboembolism: A case report

BACKGROUND

Phyllodes tumor (PT) is a solid fibroepithelial breast lesion with proliferation of stromal and epithelial elements, usually presents with a rapidly expanding feature. Venous thromboembolism (VTE) have been reported to increase the burden in terms of mortality and morbidity of malignant tumor, and associate with worsened survival. However, benign PTs with silent thromboembolism that have not yet been reported, we report an unusual case of massive benign PT that grew on the left side of the breast in a cauliflower-shaped form and presented severe chronic blood loss and deep VTE.

CASE

A 37-year-old woman with uncontrolled pain presented a rapidly enlarging left breast mass, measuring approximately 30 × 20 × 15 cm3 that first started 25 years ago. color Doppler ultrasound showed a large mass lesion on the left breast and deep VTE, several enlarged lymph nodes in the left axilla and mediastinum, which presented a malignant character. However, the biopsies of the mass did not show evidence of malignancy and the pathology result was considered to be benign PT. The patient was treated with an inferior vena cava and anticoagulation, the operation was arranged according to the surgical procedure, the patient recovered very well after mastectomy.

CONCLUSION

This case is unique in that the giant breast mass presented with malignant character, was eventually pathologically confirmed to be benign PT, and it's rare that the benign tumor accompanied with silent thromboembolism. This finding describes the atypia features of giant benign PT and reminds the surgeon to consider the factor of VTE and risk when encountering ulcerative benign breast tumor and avoid excessive treatment.

Clinico-Pathological Factors Determining Recurrence of Phyllodes Tumors of the Breast: The 25-Year Experience at a Tertiary Cancer Centre

BACKGROUND

Phyllodes tumors (PTs) of the breast are rare fibroepithelial tumors that are generally more prone to recurrence.

AIMS AND OBJECTIVES

This study aimed to assess the clinicopathological features, diagnostic modalities, and therapeutic interventions, along with their respective outcomes, to identify the factors associated with a recurrence of PTs of the breast.

METHODOLOGY

A retrospective cohort and observational study was conducted, which entailed analyzing the clinicopathological data of patients who were previously diagnosed or presented with PTs of the breast between 1996 and 2021. Data included the total number of patients diagnosed with PTs of the breast and their ages, tumor grade on initial biopsy, tumor location (left or right breast), tumor size, therapeutic interventions carried out (including surgery-either mastectomy or lumpectomy-and adjuvant radiotherapy), final tumor grade, recurrence status, type of recurrence, and time to recurrence.

RESULTS

We analyzed data on a total of 87 patients who were pathologically proven to have PTs, and 46 patients (52.87%) were found to have recurrences. All patients were female, with a mean age at diagnosis of 39 years (range 15-70). Patients aged <40 years had the highest incidence of recurrence, with a rate of 54.35% (n = 25/46), followed by patients aged >40 years, with a rate of recurrence of 45.65% (n = 21/46). A total of 55.4% of patients presented with primary PTs and 44.6% had recurrent PTs at presentation. The average time to local recurrence (LR) from the completion of treatment was 13.8 months, whereas for systemic recurrence (SR), it was 15.29 months. Surgery (mastectomy/lumpectomy) was the major determinant for local recurrence (p < 0.05).

CONCLUSION

Patients who received adjuvant radiotherapy (RT) had a minimal recurrence of PTs. Patients who were found to have a malignant biopsy on initial diagnosis (triple assessment) had a higher incidence of PTs and were more prone to SR than LR. Surgery was a determining factor in the increased rate of LR, with lumpectomy associated with a higher incidence of LR than mastectomy.

Malignant phyllodes tumor of the breast with heterologous osteosarcoma and chondrosarcomatous differentiation: A rare case report with imaging findings

Phyllodes tumors of the breast are rare fibroepithelial neoplasms accounting for 0.3%-1.5% of all female breast tumors [1,2]. Malignant transformations occur in 10%-20% of phyllodes tumors, often in the form of stroma. Heterologous osteosarcoma and chondrosarcomatous differentiation of phyllodes tumor are extremely rare, and little is known about their imaging findings. Here, we report a rare case of a 52-year-old woman with no history of previous surgery or radiation therapy, who presented with a rapidly growing right breast mass that was diagnosed as a malignant phyllodes tumor with heterologous osteosarcoma and chondrosarcomatous differentiation. The patient underwent modified radical mastectomy.

Current clinical practice in the management of phyllodes tumors of the breast: an international cross-sectional study among surgeons and oncologists

PURPOSE

Phyllodes tumors of the breast are rare fibroepithelial lesions that are classified as benign, borderline or malignant. There is little consensus on best practice for the work-up, management, and follow-up of patients with phyllodes tumors of the breast, and evidence-based guidelines are lacking.

METHODS

We conducted a cross-sectional survey of surgeons and oncologists with the aim to describe current clinical practice in the management of phyllodes tumors. The survey was constructed in REDCap and distributed between July 2021 and February 2022 through international collaborators in sixteen countries across four continents.

RESULTS

A total of 419 responses were collected and analyzed. The majority of respondents were experienced and worked in a university hospital. Most agreed to recommend a tumor-free excision margin for benign tumors, increasing margins for borderline and malignant tumors. The multidisciplinary team meeting plays a major role in the treatment plan and follow-up. The vast majority did not consider axillary surgery. There were mixed opinions on adjuvant treatment, with a trend towards more liberal regiments in patients with locally advanced tumors. Most respondents preferred a five-year follow-up period for all phyllodes tumor types.

CONCLUSIONS

This study shows considerable variation in clinical practice managing phyllodes tumors. This suggests the potential for overtreatment of many patients and the need for education and further research targeting appropriate surgical margins, follow-up time and a multidisciplinary approach. There is a need to develop guidelines that recognize the heterogeneity of phyllodes tumors.

Pretreatment Multiparametric MRI-Based Radiomics Analysis for the Diagnosis of Breast Phyllodes Tumors

BACKGROUND

Preoperative pathological grading assessment is important for patients with breast phyllodes tumors (PTs).

PURPOSE

To develop and validate a clinical-radiomics model based on multiparametric MRI and clinical information for the pretreatment differential diagnosis of PTs.

STUDY TYPE

Retrospective.

POPULATION

A total of 216 patients with PTs, 133 in the training cohort (55 benign PTs [BPTs] and 78 borderline/malignant PTs [BMPTs]) and 83 in the validation cohort (28 BPTs and 55 BMPTs).

FIELD STRENGTH/SEQUENCE

1.5 T and 3 T; T2-weighted imaging (T2WI), precontrast T1-weighted imaging (T1WI) and dynamic contrast-enhanced T1-weighted imaging (DCE-T1WI).

ASSESSMENT

A total of 3138 radiomics features were computed to decode the imaging phenotypes of PTs. To build the classification models, the following workflow was followed: minimum-maximum scaling normalization method, recursive feature elimination based on ridge regression (Ridge-RFE), synthetic minority oversampling technique, and support vector machine classifier. We established several models based on the statistically significant features (Ridge-RFE selected) of each sequence to distinguish BPTs from BMPTs, including precontrast T1WI model, DCE-T1WI phase 1 model, T1WI feature fusion model, T2WI model, T1WI + T2WI model, clinical feature model, conventional MRI characteristics model, and combined clinical-radiomics model.

STATISTICAL TESTS

Univariate analysis was utilized to compare variables between the BPT and BMPT groups. The receiver operating characteristic curve (ROC) analysis was used to evaluate the diagnostic performance of these models.

RESULTS

In the training cohort, the clinical-radiomics model had excellent diagnostic efficiency, with an area under ROC (AUC) of 0.91 ± 0.02 (95% CI: 0.87-0.94). In the validation cohort, the AUCs were 0.79 ± 0.05 (95% CI: 0.70-0.87) for the combined model and 0.77 ± 0.05 (95% CI: 0.67-0.85) for the radiomics model.

DATA CONCLUSION

Compared with conventional MRI characteristics, radiomics features extracted from multiparametric MRI are helpful for improving the accuracy of differentiating the pathological grades of PTs preoperatively. The model based on radiomics and clinical information is expected to become a potential noninvasive tool for the assessment of PTs grades.

EVIDENCE LEVEL

4 TECHNICAL EFFICACY: Stage 2.

The Predictive Value of Magnetic Resonance Imaging-based Texture Analysis in Evaluating Histopathological Grades of Breast Phyllodes Tumor

PURPOSE

Knowing the distinction between benign and borderline/malignant phyllodes tumors (PTs) can help in the surgical treatment course. Herein, we investigated the value of magnetic resonance imaging-based texture analysis (MRI-TA) in differentiating between benign and borderline/malignant PTs.

METHODS

Forty-three women with 44 histologically proven PTs underwent breast MRI before surgery and were classified into benign (n = 26) and borderline/malignant groups (n = 18 [15 borderline, 3 malignant]). Clinical and routine MRI parameters (CRMP) and MRI-TA were used to distinguish benign from borderline/malignant PT. In total, 298 texture parameters were extracted from fat-suppression (FS) T2-weighted, FS unenhanced T1-weighted, and FS first-enhanced T1-weighted sequences. To evaluate the diagnostic performance, receiver operating characteristic curve analysis was performed for the K-nearest neighbor classifier trained with significantly different parameters of CRMP, MRI sequence-based TA, and the combination strategy.

RESULTS

Compared with benign PTs, borderline/malignant ones presented a higher local recurrence (p = 0.045); larger size (p < 0.001); different time-intensity curve pattern (p = 0.010); and higher frequency of strong lobulation (p = 0.024), septation enhancement (p = 0.048), cystic component (p = 0.023), and irregular cystic wall (p = 0.045). TA of FS T2-weighted images (0.86) showed a significantly higher area under the curve (AUC) than that of FS unenhanced T1-weighted (0.65, p = 0.010) or first-enhanced phase (0.72, p = 0.049) images. The texture parameters of FS T2-weighted sequences tended to have a higher AUC than CRMP (0.79, p = 0.404). Additionally, the combination strategy exhibited a similar AUC (0.89, p = 0.622) in comparison with the texture parameters of FS T2-weighted sequences.

CONCLUSION

MRI-TA demonstrated good predictive performance for breast PT pathological grading and could provide surgical planning guidance. Clinical data and routine MRI features were also valuable for grading PTs.

Diagnosis and management of phyllodes tumours for the surgeon: An algorithm

A Phyllodes Tumour (PT) is an uncommon fibroepithelial lesion, with three histological grades - benign, borderline and malignant. PTs cause significant challenges in diagnosis, management and prognostication. Recent publications have clarified the definitions and prognostication of PTs. Contemporary data currently challenge international guidelines on PT management. We performed an in-depth literature review to develop a best-practice management algorithm for PTs. Diagnostic recommendations are that neither current imaging techniques, nor fine-needle biopsies, can reliably diagnose a PT. Core needle biopsy is the optimal diagnostic technique. Indeterminate or suspicious lesions are recommended to undergo an excisional biopsy due to the inherently heterogeneous nature of PTs. Management guidelines are that benign PTs should be completely excised, although an involved margin is acceptable in select situations. Borderline PTs should have a clear margin on excision due to their higher risk of recurrence, as well as the potential for a recurrence to progress to a malignant PT. In malignant PTs, a margin of 3 mm is acceptable as there is no reduction in recurrence risk if margins are >3 mm. Routine axillary surgery is not indicated in PTs, with axillary surgery only indicated in a histologically-confirmed positive axilla. Adjuvant treatment recommendations are that borderline and malignant PTs should be discussed at MDT, with radiotherapy considered in both. Chemotherapy should be discussed in malignant PT patients. In summary, we have developed an up-to-date simple algorithm to guide the surgeon's management of patients diagnosed with PTs and reduce excessive surgery.

The Potential Value of Texture Analysis Based on Dynamic Contrast-Enhanced MR Images in the Grading of Breast Phyllode Tumors

Purpose

To explore the value of texture analysis (TA) based on dynamic contrast-enhanced MR (DCE-MR) images in the differential diagnosis of benign phyllode tumors (BPTs) and borderline/malignant phyllode tumors (BMPTs).

Methods

A total of 47 patients with histologically proven phyllode tumors (PTs) from November 2012 to March 2020, including 26 benign BPTs and 21 BMPTs, were enrolled in this retrospective study. The whole-tumor texture features based on DCE-MR images were calculated, and conventional imaging findings were evaluated according to the Breast Imaging Reporting and Data System (BI-RADS). The differences in the texture features and imaging findings between BPTs and BMPTs were compared; the variates with statistical significance were entered into logistic regression analysis. The receiver operating characteristic (ROC) curve was used to assess the diagnostic performance of models from image-based analysis, TA, and the combination of these two approaches.

Results

Regarding texture features, three features of the histogram, two features of the gray-level co-occurrence matrix (GLCM), and three features of the run-length matrix (RLM) showed significant differences between the two groups (all p < 0.05). Regarding imaging findings, however, only cystic wall morphology showed significant differences between the two groups (p = 0.014). The areas under the ROC curve (AUCs) of image-based analysis, TA, and the combination of these two approaches were 0.687 (95% CI, 0.518–0.825, p = 0.014), 0.886 (95% CI, 0.760–0.960, p < 0.0001), and 0.894 (95% CI, 0.754–0.970, p < 0.0001), respectively.

Conclusion

TA based on DCE-MR images has potential in differentiating BPTs and BMPTs.

Malignant Phyllodes Tumor: Imaging Features With Histopathologic Correlation

Phyllodes tumors (PT) are rare fibroepithelial lesions of the breast that commonly present as rapidly enlarging, palpable masses. Phyllodes tumors may be classified as benign, borderline, or malignant on the basis of histopathologic analysis. Although malignant PT cannot be distinguished from benign PT on the basis of imaging findings alone, studies suggest that malignant PT tend to be larger and irregular in shape, and they are less likely to have circumscribed margins. If biopsy results are indeterminate, excisional biopsy should be performed. Malignant PT can be difficult to distinguish histologically from sarcomas and spindle cell metaplastic breast carcinoma; the distinction is important for prognosis and treatment. Malignant PT are treated surgically with wide local excision, without a clear role for adjuvant radiation or chemotherapy in most cases. Nearly one-third of malignant PT recur locally, usually within a few years after initial diagnosis. Distant metastatic disease is rare, and the five-year overall survival rate of malignant PT is close to 80%. The purpose of this article is to review the clinical presentation, imaging appearance, histopathology, and management of malignant PT.

Large borderline phyllodes breast tumor related to histopathology, diagnosis, and treatment management - case report

Breast phyllodes tumors (PTs) are uncommon tumors with a biphasic fibroepithelial component, characterized by rapid development in middle-aged women. A correct preoperative diagnosis after Tru-Cut biopsy allows for proper surgical planning. The treatment of choice remains surgery (wide local excision or mastectomy) with or without breast reconstruction, depending on the size and histopathological (HP) nature of the tumor. We reported a case of a 50-year-old woman with a large PT in her left breast, measuring 11/10 cm. Preoperative HP examination revealed biphasic proliferation, with the appearance of benign PT. The patient underwent a left mastectomy, with a favorable postoperative evolution. The final HP diagnosis was borderline PT, with areas of lipomatous metaplasia. After three months, breast reconstruction was performed. The therapeutic management of large PTs continues to be a challenge for pathologists and surgeons. Due to the increased frequency of local recurrence and HP progression to malignancies, the treatment of choice for these patients is mastectomy, without lymphadenectomy.

Phyllodes Tumors: A Scoping Review of the Literature

PURPOSE

Phyllodes tumors are rare tumors of the breast, with most literature being retrospective with limited guidelines on the management of these patients. Scoping review was performed to highlight themes and gaps in the available literature.

METHODS

A scoping review of the literature was performed as per PRISMA-ScR guidelines with titles, abstracts, and full texts reviewed in duplicate. Data were abstracted and summarized in categories of diagnostics, surgical management, adjuvant therapies, treatment of recurrence, and surveillance. Quality assessment was performed for each paper.

RESULTS

The search identified 4498 references, 434 full-text papers were reviewed, and 183 papers were included. Ultrasound, magnetic resonance imaging, and core needle biopsy are valuable preoperative diagnostics tools. Pathology reporting should include stromal overgrowth, stromal cellularity, nuclear atypia, mitotic rate, borders, and presence of heterologous elements. Ki67 may have a role in grading and prognosticating. Breast conservation is safe in all grades of phyllodes but may be associated with increased local recurrence in malignant phyllodes. Surgical margins should depend on grade. Axillary node positivity rate is very low, even with clinically enlarged lymph nodes. Adjuvant radiation is a useful tool to decrease local recurrence in malignant phyllodes tumors, tumors > 5 cm, age < 45 years, close margins, and breast conservation. There is no evidence supporting adjuvant chemotherapy. Recurrence can be managed with repeat wide excision; however, mastectomy is associated with lower re-recurrence. Surveillance protocols are variable in the literature.

CONCLUSIONS

There is heterogeneity in the literature on phyllodes tumors. Consensus guidelines based on the literature will help provide evidence-based care.

Predicting the pathological grade of breast phyllodes tumors: a nomogram based on clinical and magnetic resonance imaging features

OBJECTIVE

To explore the potential factors related to the pathological grade of breast phyllodes tumors (PTs) and to establish a nomogram to improve their differentiation ability.

METHODS

Patients with PTs diagnosed by post-operative pathology who underwent pretreatment magnetic resonance imaging (MRI) from January 2015 to June 2020 were retrospectively reviewed. Traditional clinical features and MRI features evaluated according to the fifth BI-RADS were analyzed by statistical methods and introduced to a stepwise multivariate logistic regression analysis to develop a prediction model. Then, a nomogram was developed to graphically predict the probability of non-benign (borderline/malignant) PTs.

RESULTS

Finally, 61 benign, 73 borderline and 48 malignant PTs were identified in 182 patients. Family history of tumor, diameter, lobulation, cystic component, signal on fat saturated T₂ weighted imaging (FS T₂WI), BI-RADS category and time-signal intensity curve (TIC) patterns were found to be significantly different between benign and non-benign PTs. The nomogram was finally developed based on five risk factors: family history of tumor, lobulation, cystic component, signal on FS T₂WI and internal enhancement. The AUC of the nomogram was 0.795 (95% CI: 0.639, 0.835).

CONCLUSION

Family history of tumor, lobulation, cystic components, signals on FS T₂WI and internal enhancement are independent predictors of non-benign PTs. The prediction nomogram developed based on these features can be used as a supplemental tool to pre-operatively differentiate PTs grades.

ADVANCES IN KNOWLEDGE

More sample size and characteristics were used to explore the factors related to the pathological grade of PTs and establish a predictive nomogram for the first time.

Differential diagnosis between small breast phyllodes tumors and fibroadenomas using artificial intelligence and ultrasound data

Background

It is challenging to differentiate between phyllodes tumors (PTs) and fibroadenomas (FAs). Artificial intelligence (AI) can provide quantitative information regarding the morphology and textural features of lesions. This study attempted to use AI to evaluate the ultrasonic images of PTs and FAs and to explore the diagnostic performance of AI features in the differential diagnosis of PTs and FAs.

Methods

A total of 40 PTs and 290 FAs <5 cm in maximum diameter found in female patients were retrospectively analyzed. All tumors were segmented by doctors, and the features of the lesions were collated, including circularity, height-to-width ratio, margin spicules, margin coarseness (MC), margin indistinctness, margin lobulation (ML), internal calcification, angle between the long axis of the lesion and skin, energy, grey entropy, and grey mean. The differences between PTs and FAs were analyzed, and the diagnostic performance of AI features in the differential diagnosis of PTs and FAs was evaluated.

Results

Statistically significant differences (P<0.05) were found in the height-to-width ratio, ML, energy, and grey entropy between the PTs and FAs. Receiver operating characteristic (ROC) curve analysis of single features showed that the area under the curve [(AUC) 0.759] of grey entropy was the largest among the four features with statistically significant differences, and the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 0.925, 0.459, 0.978, and 0.190, respectively. When considering the combinations of the features, the combination of height-to-width ratio, margin indistinctness, ML, energy, grey entropy, and internal calcification was the most optimal of the combinations of features with an AUC of 0.868, and a sensitivity, specificity, PPV, and NPV of 0.734, 0.900, 0.982, and 0.316, respectively.

Conclusions

Quantitative analysis of AI can identify subtle differences in the morphology and textural features between small PTs and FAs. Comprehensive consideration of multiple features is important for the differential diagnosis of PTs and FAs.

Malignant Phyllodes Tumor of the Breast: A Practice Review

Introduction: Phyllodes tumor (PT) of the breast, particularly malignant phyllodes tumor (mPT), is a rare fibroepithelial neoplasm. A complex diagnosis is based on pathologic, radiologic, and clinical findings, with controversies about what is the best therapeutic strategy. Objective: Our objective was to provide an overview of the clinical, pathologic, and therapeutic aspects of this rare tumor. Conclusions: mPT is a rare presentation of breast cancer and a challenge in clinical practice. A multidisciplinary approach should take into account some aspects like pathogenic mutations and hereditary syndromes. Oncologic surgery is the fundamental approach, and the use of adjuvant therapies is still controversial due to the lack of clinical trials. Treatment recommendations should be individualized according to patient risk and preferences. Prospective studies are fundamental to clarifying the best treatment for these tumors.

Value of conventional magnetic resonance imaging texture analysis in the differential diagnosis of benign and borderline/malignant phyllodes tumors of the breast

BACKGROUND

The purpose of this study was to determine the potential value of magnetic resonance imaging (MRI) texture analysis (TA) in differentiating between benign and borderline/malignant phyllodes tumors of the breast.

METHODS

The preoperative MRI data of 25 patients with benign phyllodes tumors (BPTs) and 19 patients with borderline/malignant phyllodes tumors (BMPTs) were retrospectively analyzed. A gray-level histogram and gray-level cooccurrence matrix (GLCM) were used for TA with fat-suppressed T2-weighted imaging (FS-T2WI), diffusion-weighted imaging (DWI), apparent diffusion coefficient (ADC) images, and 2- and 7-min postcontrast T1W images on dynamic contrast-enhanced MRI (DCE-T1WI_2min and DCE-T1WI_7min) between BPTs and BMPTs. Independent sample t-test and Mann-Whitney U test were performed for intergroup comparison. A regression model was established by using binary logistic regression analysis, and receiver operating characteristic (ROC) curve analysis was carried out to evaluate diagnostic efficiency.

RESULTS

For ADC images, the texture parameters angular second moment (ASM), correlation, contrast, entropy and the minimum gray values of ADC images (ADC_Minimum) showed significant differences between the BPT group and BMPT group (all p<0.05). The parameter entropy of FS-T2WI and the maximum gray values and kurtosis of the tumor solid region of DCE-T1WI_7min also showed significant differences between these two groups. Except for ADC_Minimum, angular second moment of FS-T2WI (FS-T2WI_ASM), and the maximum gray values of DCE-T1WI_7min (DCE-T1WI_7min-Maximum) of the tumor solid region, the AUC values of other positive texture parameters mentioned above were greater than 0.75. Binary logistic regression analysis demonstrated that the contrast of ADC images (ADC_Contrast) and entropy of FS-T2WI (FS-T2WI_Entropy) could be considered independent texture variables for the differential diagnosis of BPTs and BMPTs. Combined, the AUC of these parameters was 0.891 (95% CI: 0.793-0.988), with a sensitivity of 84.2% and a specificity of up to 89.0%.

CONCLUSION

Texture analysis could be helpful in improving the diagnostic efficacy of conventional MR images in differentiating BPTs and BMPTs.

Giant Benign Mammary Phyllodes Tumor: Report of a Case and Review of the Literature

Phyllodes tumor of the breast is an infrequently encountered fibroepithelial neoplasm, which accounts for 0.3–1% of all tumors. Few case reports have described the occurrence of giant phyllodes tumor. To our knowledge, about 20% of phyllodes tumors would be considered giant benign. Complete surgical excision is the standard of care for giant benign phyllodes tumors; axillary lymph node metastasis is rare, and dissection should be limited to patients with pathologic evidence of tumor in the lymph nodes. We report the case of a 40-year-old Mexican woman with giant mammary tumor who underwent a right total mastectomy. The pathology results showed a benign phyllodes tumor 4,857 g in weight and 40.2 × 36.3 × 15 cm in size. We do not suggest adjuvant radiation therapy for patients with benign phyllodes tumors that are widely excised. A review of the pertinent literature was performed.

Phyllodes Tumors of the Breast: A Single-Center Experience

Objective

We aimed to analyze the clinicopathological findings, treatment approach, and treatmen outcomes in patients diagnosed with phyllodes tumor (PT).

Materials and Methods

The clinicopathological data of 26 patients with PT, who were treated between 2008 and 2019, were retrospectively analyzed.

Results

Mean age was 35.07±13.95 years (range: 14-71), while mean tumor size was 54.76±29.24 mm (range: 25-135). Benign, borderline, and malignant PT were detected in 18 (69.2%), 3 (11.5%), and 5 (19.2%) patients, respectively. Marginless excision was performed in 20 patients (76.9%), while six (23.1%) patients underwent mastectomy. A statistically significant correlation of tumor type with mean tumor size and mean age was observed (p=0.041 and p=0.013, respectively). Margin positivity on first excision was more frequent in the malignant tumors (p=0.02). No statistically significant correlation of PT type with presence of breast cancer in the family history, and tumor localization was observed (p=0.79 and p=0.13, respectively). Mean postoperative follow-up duration was 56 months (range: 6-147). Local recurrence was not observed in any of the patients. Lung and left vastus lateralis muscle metastases were encountered. The patient with lung metastasis became exitus because of the same reason 6 months after detection of the metastasis.

Conclusion

PT is a rare fibroepithelial tumor of the breast that is characterized by a mixed histology seen in younger ages when compared to the classical breast tumors. The probability of PT should be considered in the presence of a rapid-growing mass in the breast. In addition, it should also be considered that the contribution of imaging techniques may be limited.

Adenoid cystic carcinoma of the breast: a study of five cases

Adenoid cystic carcinoma of the breast is a rare type of breast cancer. Most patients present with a bilateral palpable mass. Ultrasound and mammography are non-specific and can sometimes lead to misdiagnosis because of their variable imaging features. Pathological examination is the standard reference. Surgery is the mainstay of treatment for patients. Although adenoid cystic carcinoma has an excellent prognosis, metastatic cases have been reported. This report aims to discuss the clinical and imaging features of one case of adenoid cystic carcinoma with a poor prognosis and four cases with a good prognosis at our center.

Phyllodes Tumors of the Breast (the Egyptian Experience)

Phyllodes tumors (PT) are rare fibroepithelial lesions, about 0.3-0.5% of all breast tumors. This study is an evaluation of patient characteristics, clinicopathologic features, diagnostic tools, therapeutic options, risk factors for recurrence, and distant metastasis and follow-up findings in patients with PTs. One hundred twenty-seven patients with pathologically proved PTs in the National Cancer Institute, Cairo University, Egypt, from January 2011 to January 2016 were reviewed and analyzed. Sixty patients presented with benign PTs (47.2%), 34 had borderline PTs (26.8%), and 33 had malignant PTs (26%). The mean follow-up period was approximately 36 months; local recurrence occurred in 34 patients, 9 benign cases (14.5%), 11 borderlines (32.4%), and 14 malignant PTs (42.4%). Mastectomy was the most commonly used surgery in recurrent cases (61.4%). Axillary staging was performed in 31 cases (24.4%); only 2 cases showed positive nodal metastasis (6.5%) and were of the malignant subtype. Distant metastasis occurred in 12 patients, 4 with borderline PTs, and 8 with malignant PTs. The most common site for metastasis was the lungs and bones. Adjuvant radiotherapy was applied in 9 patients, 2 in borderline phyllodes, and 7 in malignant phyllodes; post-radiotherapy recurrence occurred in 5 malignant phyllodes patients. Chemotherapy was employed in 10 metastatic patients (4 with borderline and 6 with malignant phyllodes); excision with clear margins is important to reduce the local recurrence. Routine axillary staging should not be done. The adjuvant radiation therapy is still controversial. Local recurrence can develop even after appropriate surgery. Therefore, close follow-up is mandatory.

Malignant Phyllodes Tumor of the Breast in a 26-year-old Woman

Breast cancer is the most commonly diagnosed cancer and the second leading cause of cancer death in women. Early detection, accurate diagnosis and proper treatment are important prognostic factors due to the wide variety of breast cancer subtypes. This becomes of particular importance with rare breast tumors, which are difficult to diagnose due to their varying presentations. Malignant phyllodes tumor (PT) is one of the rare breast tumors that is difficult to diagnose. First reported in 1838, PT of the breast accounts for less than 1% of all breast masses. Based on histological features, PT is categorized on a spectrum of benign to malignant tumors. High-grade PTs are commonly seen in older patients but can also occur in young patients, as reported in this case of a 26-year-old female. Failure to detect the malignancy early and initiate appropriate treatment can lead to widespread metastasis and poor outcomes.

Distinction between phyllodes tumor and fibroadenoma in breast ultrasound using deep learning image analysis

Purpose

To evaluate the accuracy of a deep learning software (DLS) in the discrimination between phyllodes tumors (PT) and fibroadenomas (FA).

Methods

In this IRB-approved, retrospective, single-center study, we collected all ultrasound images of histologically secured PT (n = 11, 36 images) and a random control group with FA (n = 15, 50 images). The images were analyzed with a DLS designed for industrial grade image analysis, with 33 images withheld from training for validation purposes. The lesions were also interpreted by four radiologists. Diagnostic performance was assessed by the area under the receiver operating characteristic curve (AUC). Sensitivity, specificity, negative and positive predictive values were calculated at the optimal cut-off (Youden Index).

Results

The DLS was able to differentiate between PT and FA with good diagnostic accuracy (AUC = 0.73) and high negative predictive value (NPV = 100%). Radiologists showed comparable accuracy (AUC 0.60–0.77) at lower NPV (64–80%). When performing the readout together with the DLS recommendation, the radiologist’s accuracy showed a non-significant tendency to improve (AUC 0.75–0.87, p = 0.07).

Conclusion

Deep learning based image analysis may be able to exclude PT with a high negative predictive value. Integration into the clinical workflow may enable radiologists to more confidently exclude PT, thereby reducing the number of unnecessary biopsies.

Radiopathological characteristics and outcomes of phyllodes tumor of the breast in Malaysian women

Phyllodes tumor or cystosarcoma phyllodes is a rare fibroepithelial neoplasm which arises from the periductal stroma of the breast. They are classified as benign, borderline, and malignant based on the histologic features. However, all phyllodes tumor (PT) subtypes are regarded as having malignant potential and correct diagnosis is important for surgical management and optimal care. This study is a retrospective review of 76 women diagnosed as PT with highlights on the imaging characteristics, pathology, and surgical treatment over a 7-year period in a tertiary medical center of urban population in Malaysia. There were 45 benign, 16 borderline, and 15 malignant PT. The median age for benign PT was 43, borderline 48.5, and malignant 42 years. The Malay ethnic group constitute 52.6% of cases, with 27.6% and 18.4% in Chinese and Indian ethnic groups, respectively. On mammograms, most benign (64.3%) and 33.3% of malignant PT showed high-density lesions. Calcifications were only seen in 2 benign PT. On ultrasound, 86% of benign PT was well-circumscribed whilst 50.0% of malignant PT had irregular outline. Cystic spaces were seen in 40.0% of malignant and 9.5% of benign PT. 80% of malignant PT lesions were heterogenous. Malignant PT demonstrates tumor heterogeneity, cystic spaces, and posterior acoustic enhancement on ultrasound. Half of malignant PT showed regular borders on ultrasound and appear well circumscribed on mammogram. A total of 46 patients had wide local excision or excision biopsy whilst 30 underwent mastectomy as primary treatment. The majority of the borderline and malignant PTs in our study (75.0% and 85.7% respectively) and only 5 out of the 43 (11.6%) benign PT underwent mastectomy. There were 2 tumor recurrence in the benign PT group and 1 case in the borderline and malignant group respectively.

Phyllodes Tumor of the Breast: Ultrasound-Pathology Correlation

OBJECTIVE

The purpose of this study is to evaluate the sonographic and histopathologic features distinguishing benign from borderline and malignant phyllodes tumors.

MATERIALS AND METHODS

The ultrasound examinations of women with pathologically proven phyllodes tumors from 2004 to 2011 were retrospectively reviewed. The sonographic features of benign, borderline, and malignant phyllodes tumors were compared and analyzed using the American College of Radiology's BI-RADS ultrasound lexicon. Fisher exact test and Wilcoxon rank sum test were used for statistical analysis.

RESULTS

Fifty-nine women were included in the study; 28 benign (47%), 19 malignant (32%), and 12 borderline (20%) phyllodes tumors were identified. Significant univariate predictors of increased risk of borderline or malignant phyllodes tumors were patient age greater than 55 years (p = 0.014), irregular lesion shape (p = 0.011), and longest lesion dimension greater than 7 cm (p = 0.0022) at sonography. No significant differences were observed in lesion margins, boundaries, echo patterns, or posterior acoustic features.

CONCLUSION

There is substantial overlap in the sonographic features of benign and borderline or malignant phyllodes tumors. Understanding the clinical and sonographic features of phyllodes tumors may aid the radiologist in predicting biological behavior, including the likelihood of benign versus borderline or malignant phyllodes tumors at pathologic analysis.

Case Report: Metastatic Phyllodes Tumor

This report describes the clinical presentation, imaging findings, and treatment options of a case of metastatic malignant phyllodes.

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.

Lipomatous tumors of the breast: A contemporary review

Breast tumors with lipomatous or liposarcomatous components are infrequently encountered, but can be a source of diagnostic difficulty if the context of the fatty differentiation is not recognized. Among the true adipocytic tumors, lipoma is the most common lipomatous tumor arising in the breast. Several mammary spindle cell tumors may show adipocytic differentiation, including fibroepithelial tumors and myofibroblastoma. Liposarcomatous components most often arise in malignant phyllodes tumors, as opposed to primary liposarcomas of the breast which are believed to be uncommon. This article will review the spectrum fat-containing tumors of the breast with an emphasis on differential diagnosis and insights from recent molecular studies.

First ultrasound diagnosis of BI-RADS 3 lesions in young patients: Can 6-months follow-up be sufficient to assess stability?

OBJECTIVES

To evaluate the outcome of repeated short-term follow-up with ultrasound in no high-risk young patients with a BI-RADS3 lesion at first examination.

METHODS

In this IRB-approved study 492 women, aged 18-34 years (mean±standard deviation, 28±4.5years) with first breast ultrasound examination in 2012-2014 were retrospectively evaluated. Inclusion criteria were: at least one BI-RADS3 lesion and (a) biopsy/surgical excision or (b) follow-up of at least 18 months (including a 6-month follow-up). BI-RADS category assigned during follow-up and pathologic findings in cases undergoing biopsy/surgical excision were collected. At the 6- and 18-month follow-up the recommended biopsy rates (RBR) and the corresponding positive predictive value (PPV) were calculated.

RESULTS

In 97 patients, 151 BI-RADS3 lesions were identified. Biopsy/surgical excision was initially performed in 25/151 (16.5%) lesions. After 6-month, category was downgraded to BI-RADS1/2 in 23/126 (15.3%) and upgraded to BI-RADS4 in 9/126 lesions (7.1%). Pathological diagnosis of these lesions was fibroadenoma in 5 and benign phyllodes tumor in 4 cases (RBR 7%, PPV_bio 44.4%). After 18-month one lesion was classified BI-RADS4 and pathological diagnosis was fibroadenoma (RBR 1.1%, PPV_bio 0%).

CONCLUSIONS

Our preliminary data show that follow-up imaging performed after 18 months from a first BI-RADS3 diagnosis does not affect clinical treatment and 6-month follow-up may be sufficient to assess the stability of probably benign lesions.

Synchronous Malignant Phyllodes Tumor with Skin Ulceration and Invasive Carcinoma as Collision Tumor

Phyllodes tumor is a rare fibroepithelial biphasic tumor of the breast composed of hypercellular mesenchymal stroma and double-layered epithelial component, arranged in clefts with leaf-like projections. Phyllodes tumor with coincidental presence of invasive carcinoma or in situ ductal carcinoma in the same or distinct breast is a rare occurrence, documented by some reports. Invasive carcinoma can be seen within or outside the phyllodes tumor. Skin ulceration by malignant phyllodes tumor with coexisting invasive carcinoma as collision tumor is extremely rare. Here, we report an extremely rare presentation of malignant phyllodes tumor as a giant fungating mass with distinct invasive carcinoma in the same breast in a 51-year-old female.

Phyllodes Tumor of the Breast: Analysis of 48 Patients

OBJECTIVE

Phyllodes tumor (PT) is a rare biphasic breast neoplasm that accounts for less than 1% of all breast tumors. The aim of this study was to evaluate the clinicopathologic features, diagnostic difficulties, and therapeutic outcomes of patients with PT.

MATERIALS AND METHODS

A total of 48 female patients who underwent surgery for PT were included in the study. Patient characteristics, clinicopathologic features of tumors, diagnostic findings, surgical outcomes, adjuvant therapies, and follow-up findings were retrospectively evaluated.

RESULTS

The mean age of patients was 35 years. Painless breast mass was the most common (85.4%) presenting symptom. Total excision with at least 1 cm macroscopic clear margins was the most frequently performed (87.5%) surgery. Most patients (n=34, 70.8%) had benign PT; however, borderline and malignant tumors were found in 9 (18.8%) and 5 (10.4%) patients, respectively. During the mean follow-up period of approximately 30 months, local and distant recurrence was detected in three (6.3%) patients and one (2.1%) patient, respectively. Patients with malignant PT had larger tumors than those with benign and borderline PTs (p=0.010). No significant difference in other clinical, diagnostic, and pathologic characteristics was found between the groups.

CONCLUSION

PT can be easily confused with other breast masses such as fibroadenoma due to the non-specific clinical and radiologic findings. Surgical excision with at least 1 cm clear margins is of great importance to reduce the risk of local recurrence. However, recurrence can develop even after appropriate surgery, thus patients should be closely followed up after surgery.

How to approach phyllodes tumors of the breast?

OBJECTIVE

Phyllodes tumor of the breast is a rare fibroepithelial breast tumor that comprise 0.3-0.9% of primary breast neoplasms. In this study, we aimed to present clinicopathologic symptoms of our patients along with their treatment modality.

MATERIAL AND METHODS

Clinicopathologic properties and treatment modality of 20 phyllodes tumor patients who underwent surgery between January 2008 and January 2013 were retrospectively evaluated.

RESULTS

Median patient age was 47 years (22-75). Fine-needle aspiration biopsy was applied to 19 patients. Biopsy results were reported as suspicious in four, malignant in three, benign in 11, and as non-diagnostic in one patient. Final histopathology reports revealed two benign, one malignant and one borderline tumor out of the four patients with suspicious findings on fine needle aspiration biopsy; all patients with malignant cytology had malignancy. There were two borderline and nine benign lesions within the benign biopsy group. Sixteen patients underwent segmental mastectomy, four patients underwent mastectomy with/without axillary dissection. The median tumor size was 6 (1-13) cm. Histopathologically, 11 (55%) tumors were benign, 5 (25%) were borderline, and 4 (20%) were malignant. Two of the four patients with malignancy underwent radiotherapy and chemotherapy, and one patient only received chemotherapy as adjuvant treatment.

CONCLUSION

Phyllodes tumors are rare, mix-type breast tumors. Due to high rates of local recurrence and potential for malignancy, preoperative diagnosis and accurate management are important.

Phyllodes tumor diagnosed after ultrasound-guided vacuum-assisted excision: should it be followed by surgical excision?

Our aim was to retrospectively evaluate the results of ultrasound (US)-guided vacuum-assisted excision (US-VAE) of phyllodes tumors (PTs). A total of 41 PTs diagnosed at US-VAE followed by surgery (n = 27) or at least 2 y of US monitoring (n = 14) were included. By comparison of US-VAE pathology with surgical histology or follow-up US results, cases were divided into upgraded (malignant) and non-upgraded (benign) groups. These two groups were compared with respect to clinical, procedural and US features. Among 27 surgical cases, 2 (8.7%) of 23 benign PTs were upgraded to malignant PTs. The Breast Imaging Reporting and Data System category was retrospectively assigned as 4a (50%) or 4b (50%) in the upgraded group (n = 2) and 3 (64%) or 4a (36%) in the non-upgraded group (n = 39) (p = 0.018). Residual tumor was observed at the site of US-VAE in 15 of 27 surgical cases and 0 of 14 US follow-up cases (36.6%, 15/41). Given the rates of upgrade to malignancy (8.7%) and residual tumor (36.6%), PTs diagnosed after US-VAE should be surgically excised.

Phyllodes tumours of the breast: radiological presentation, management and follow-up

OBJECTIVE

Phyllodes tumours (PTs) are rare neoplasms accounting for <1% of breast lesions. With increased breast awareness and screening programmes, smaller PTs are being detected. The purpose of this study was to determine the clinical, radiological and pathological presentation of PTs and to evaluate the role of imaging follow-up, for which there are no specific guidelines.

METHODS

A retrospective study of all patients diagnosed with PT in a symptomatic unit between January 2006 and March 2013 was carried out. Patients were identified using breast care and electronic patient record databases.

RESULTS

53 patients with 54 lesions were diagnosed as having a PT. The median age was 27.5, 35.0 and 38.5 years for benign, borderline and malignant PT, respectively. Borderline and malignant PTs were larger than benign PTs, with mean sizes of 33 and 42 mm compared with 29 mm. 38% of PTs were labelled by the reporting radiologist as fibroadenomas, including two borderline PTs and one malignant PT. In 24% of cases, the radiologist raised the possibility of PT in the report. 17 patients (40%) developed a new fibroepithelial breast lesion during follow-up of which 4 were recurrent PTs.

CONCLUSION

Despite adequate surgical management, the development of further fibroepithelial lesions in the ipsilateral breast is common. 3-year clinical surveillance, with the addition of 6-monthly ultrasound is advised for females with initial borderline or malignant PT histology.

ADVANCES IN KNOWLEDGE

We propose a follow-up protocol with ultrasound based on the grade of the PT diagnosed for 3 years to detect recurrence.

Imaging of the adolescent breast

The mainstay of breast imaging in the adolescent is ultrasonography. There is occasionally a need for additional imaging, particularly with magnetic resonance imaging (MRI). Imaging of the adolescent breast differs substantially from the adult in both the imaging modalities utilized and the relative likelihood of pathologies encountered. The majority of lesions in the adolescent are benign, but the presence of a breast lesion may cause anxiety to patients and their families due to the wide awareness of breast malignancy in the adult population. It is important to be aware of the imaging modalities available to image the adolescent breast to prevent unnecessary radiation exposure while answering the clinical question. The current recommendations for adolescent diagnostic and screening breast imaging will be reviewed. Benign breast lesions such as fibroadenomas, fibrocystic change, pseudoangiomatous stromal hyperplasia, gynecomastia, and posttraumatic or infectious lesions with their associated imaging findings and management will be outlined. Additionally, review of breast malignancies that can affect adolescents will provide the reader with features to distinguish benign from malignant processes in the adolescent based on imaging findings and clinical presentation.

Diagnosis and management of benign, atypical, and indeterminate breast lesions detected on core needle biopsy

Imaging abnormalities detected by mammographic screening often lead to diagnostic evaluations, with suspicious abnormalities subjected to image-guided core needle biopsy (CNB) to exclude malignancy. Most CNBs reveal benign pathological alterations, termed benign breast disease (BBD). Adoption of CNB presents challenges with pathologic classification of breast abnormalities and management of patients with benign or atypical histological findings. Patient management and counseling after CNB diagnosis of BBD depends on postbiopsy determination of radiologic-pathologic concordancy. Communication between radiologists and pathologists is crucial in patient management. Management is dependent on the histological type of BBD. Patients with concordant pathologic imaging results can be reassured of benign biopsy findings and advised about the future risk of developing breast cancer. Surgical consultation is advised for patients with discordant findings, symptomatic patients, and high-risk lesions. This review highlights benign breast lesions that are encountered on CNB and summarizes management strategies. For this review, we conducted a search of PubMed, with no date limitations, and used the following search terms (or a combination of terms): atypical ductal hyperplasia, atypical hyperplasia, atypical lobular hyperplasia, benign breast disease, cellular fibroepithelial lesions, columnar cell lesions, complex sclerosing lesion, core needle biopsy, fibroadenomas, flat epithelial atypia, lobular carcinoma in situ, lobular neoplasia, mucocele-like lesions, phyllodes tumor, pseudoangiomatous stromal hyperplasia, radial scar, and vascular lesions. The selection of references included in this review was based on study relevance and quality. We used additional articles culled from the bibliographies of retrieved articles to examine the published evidence for risk factors of BBD.