Phyllodes tumors (PT) are rare fibroepithelial neoplasms of the breast with unpredictable behavior. We reviewed our single institution experience with PT over 51 years to identify factors predictive of local recurrence (LR) and metastasis.From 1954 to 2005, a total of 352 cases of PT were identified; 293 had follow-up. All available pathology slides (90%) were rereviewed for margins, borders, fibroproliferation in the surrounding breast tissue, stromal pattern, stromal cellularity, frequency of mitoses, and necrosis.All cases occurred in women, with a median age of 42, with 203 originally categorized as benign and 90 as malignant. Median follow-up was 7.9 years. A total of 35 patients developed LR at a median of 2 years. In univariate analyses, a higher actuarial LR rate was associated with positive margins (P =.04), fibroproliferation (P =.001), and necrosis (P =.006). PT classified as malignant did not have a higher risk of LR (P =.79). Five patients developed distant disease at a median of 1.2 years. These patients constituted 71% of the seven patients who had uniformly aggressive pathologic features, including large tumor size (>or=7.0 cm), infiltrative borders, marked stromal overgrowth, marked stromal cellularity, high mitotic count, and necrosis.Positive margins, fibroproliferation in the surrounding breast tissue, and necrosis are associated with a marked increase in LR rates. Efforts should be made to achieve negative surgical margins to reduce risk of LR. Death from PT is rare (2%), and only PT that demonstrate uniformly aggressive pathologic features seem to be associated with mortality.

Phyllodes tumours constitute an uncommon but complex group of mammary fibroepithelial lesions. Accurate and reproducible grading of these tumours has long been challenging, owing to the need to assess multiple stratified histological parameters, which may be weighted differently by individual pathologists. Distinction of benign phyllodes tumours from cellular fibroadenomas is fraught with difficulty, due to overlapping microscopic features. Similarly, separation of the malignant phyllodes tumour from spindle cell metaplastic carcinoma and primary breast sarcoma can be problematic. Phyllodes tumours are treated by surgical excision. However, there is no consensus on the definition of an appropriate surgical margin to ensure completeness of excision and reduction of recurrence risk. Interpretive subjectivity, overlapping histological diagnostic criteria, suboptimal correlation between histological classification and clinical behaviour and the lack of robust molecular predictors of outcome make further investigation of the pathogenesis of these fascinating tumours a matter of active research. This review consolidates the current understanding of their pathobiology and clinical behaviour, and includes proposals for a rational approach to the classification and management of phyllodes tumours. © 2015 John Wiley & Sons Ltd.

Phyllodes tumors are rare breast neoplasms with limited prospective data to guide treatment, leading to heterogeneous management of this disease. We developed National consensus statements using modified Delphi methodology including patients and practitioners across Canada.Statements were developed based on a literature review. Two iterations of surveys were distributed with a planned virtual consensus meeting. Panelists were invited from surgery, radiation oncology, medical oncology, pathology, radiology, and plastic surgery.Twenty-three participants attended the virtual conference. One hundred statements regarding diagnostics, pathology, surgical planning, adjuvant therapies, recurrence, surveillance, and patient support were approved with an a priori defined consensus of ≥ 80%. Two tables on locoregional management were developed and approved. The management of borderline phyllodes tumors was a source of uncertainty, and recommendations reflect the lack of evidence in this rare presentation.A consensus document containing all approved statements for the care and management of phyllodes tumors was developed to help guide practice and future research.© 2023. Society of Surgical Oncology.

Phyllodes tumor of the breast is rare and often resembles the more commonly seen fibroadenoma at imaging and histologically. As core biopsy cannot always distinguish the two, assessing radiologic-pathologic concordance is essential to guide appropriate clinical management. We review the imaging characteristics of phyllodes tumor at mammography, ultrasound, and MRI to help the interpreting radiologist be aware of key imaging features that should alert him to the possibility of a phyllodes tumor even if not verified by initial core biopsy.

The purpose of our study was to evaluate the MRI appearance of phyllodes breast tumors and to differentiate them from fibroadenomas.MR images were obtained on a 1.5-T imager. T1- and T2-weighted sequences and dynamic 2D fast-field echo T1-weighted sequences were performed. MR images of 23 patients with 24 phyllodes breast tumors (one malignant, 23 benign) were analyzed with respect to morphology and contrast enhancement. The tumors were compared with the MRI appearance of 81 fibroadenomas of 75 patients.Well-defined margins were seen in 87.5% of the phyllodes tumors and 70.4% of the fibroadenomas, and a round or lobulated shape in 100% and 90.1%, respectively. A heterogeneous internal structure was observed in 70.8% of phyllodes tumors and in 49.4% of fibroadenomas. Nonenhancing internal septations were found in 45.8% of phyllodes tumors and 27.2% of fibroadenomas. A significantly greater increase in signal was seen on T2-weighted images in the tissue surrounding phyllodes tumors (21%) compared with fibroadenomas (1.2%). Most of both lesions appeared with low signal intensity on T1- and T2-weighted images. After the administration of contrast material, 33.3% of phyllodes tumors and 22.2% of fibroadenomas showed a suspicious signal intensity-time course.Phyllodes breast tumors and other fibroadenomas cannot be precisely differentiated on breast MRI. Phyllodes tumors have benign morphologic features and contrast enhancement characteristics suggestive of malignancy in 33% of cases.

To evaluate the diagnostic performance of MRI-based radiomics model for differentiating phyllodes tumors of the breast from fibroadenomas.This retrospective study included 88 patients (32 with phyllodes tumors and 56 with fibroadenomas) who underwent MRI. Radiomic features were extracted from T2-weighted image, pre-contrast T1-weighted image, and the first-phase and late-phase dynamic contrast-enhanced MRIs. To create stable machine learning models and balanced classes, data augmentation was performed. A least absolute shrinkage and selection operator (LASSO) regression was performed to select features and build the radiomics model. A radiological model was constructed from conventional MRI features evaluated by radiologists. A combined model was constructed using both radiomics features and radiological features. Machine learning classifications were done using support vector machine, extreme gradient boosting, and random forest. The area under the receiver operating characteristic (ROC) curve (AUC) was computed to assess the performance of each model.Among 1070 features, the LASSO logistic regression selected 35 features. Among three machine learning classifiers, support vector machine had the best performance. Compared to the radiological model (AUC: 0.77 ± 0.11), the radiomics model (AUC: 0.96 ± 0.04) and combined model (0.97 ± 0.03) had significantly improved AUC values (both p < 0.01) in the validation set. The combined model had a relatively higher AUC than that of the radiomics model in the validation set, but this was not significantly different (p = 0.391).Radiomics analysis based on MRI showed promise for discriminating phyllodes tumors from fibroadenomas.• The radiomics model and the combined model were superior to the radiological model for differentiating phyllodes tumors from fibroadenomas. • The SVM classifier performed best in the current study. • MRI-based radiomics model could help accurately differentiate phyllodes tumors from fibroadenomas.© 2022. The Author(s), under exclusive licence to European Society of Radiology.

To retrospectively evaluate the magnetic resonance (MR) imaging findings of phyllodes tumor of the breast and to compare these findings with the histologic grade.Institutional review board approval and informed consent were obtained. The authors reviewed the MR findings in 30 female patients aged 16-73 years (mean, 40.2 years) with surgically confirmed phyllodes tumors. Analyzed MR findings included tumor shape, margin, internal enhancement, and size; signal intensity (SI) of tumor higher than that of normal breast tissue on T1-weighted images; SI of tumor lower than or equal to that of normal tissue on T2-weighted images; cyst wall appearance; kinetic curve assessment; and apparent diffusion coefficient (ADC). The MR findings and histologic grade were statistically analyzed to determine whether any correlations existed. Significant MR findings were compared with histopathologic findings.Nineteen benign, six intermediate (characterized by five to nine cell reproductions at 10 high-power fields, pushing or infiltrative margins, moderate stromal cellularity, and atypia and overgrowth), and five malignant phyllodes tumors were assessed. Irregular cyst wall (P =.003), tumor SI lower than or equal to normal tissue SI on T2-weighted images (P =.005), and low ADC (P =.001) correlated significantly with histologic grade. Tumor SI higher than normal tissue SI on T1-weighted images was more frequent in the malignant (in three of five tumors) and intermediate (in three of six tumors) groups than in the benign group (in two of 19 tumors); however, it was not a significant finding (P =.024). Tumor SI higher than normal tissue SI on T1-weighted images and irregular cyst wall corresponded histopathologically to hemorrhagic infarction and necrosis, respectively. Tumor SI lower than or equal to normal tissue SI on T2-weighted images and low ADC corresponded histopathologically to stromal hypercellularity. Other findings were not significant.Several MR findings can be used to help determine the histologic grade of phyllodes breast tumors.(c) RSNA, 2006.

The role of the pathologist in the preoperative diagnosis of phyllodes tumours of the breast is critical to appropriate surgical planning. However, reliable differentiation of phyllodes tumour from cellular fibroadenoma remains difficult. Preoperative diagnostic accuracy allows correct surgical treatment, avoiding the pitfalls of reoperation because of inadequate excision, or surgical overtreatment. Specific clinical indices may arouse diagnostic suspicion but are unreliable for confirmation, as with current imaging modes. Fine needle aspiration cytology has a high false negative rate. Few studies have evaluated the role of core needle biopsy, but it may prove a useful adjunct. Both diagnostic and prognostic information may in future be gained from application of immunohistochemical and other techniques assessing the expression of proliferative markers including p53, Ki-67, and others.

Complete surgical resection is the standard treatment for localized breast phyllodes tumors. Post-surgical treatments are still a matter of debate. We carried out an overview of the literature to investigate the clinical outcome of patients with phyllodes tumor. A retrospective analysis of mono-institutional series has been included as well.We reviewed all the retrospective series reported from 1951 until April 2012. We analyzed cases treated at our institution from 1999 to 2010.Eighty-three articles (5530 patients; 1956 malignant tumors) were reviewed. Local recurrences were independent of histology. Distant recurrences were more frequent in the malignant tumors (22%). A total of 172 phyllodes tumors were included in the retrospective analysis.Prognosis of phyllodes tumors is excellent. There are no convincing data to recommend any adjuvant treatment after surgery. Molecular characterization may well provide new clues to permit identification of active treatments for the rare poor prognosis cases.Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Phyllodes tumors (PTs) are rare breast tumors that usually occur in middle-aged women. Here we discuss our recent experiences in the diagnosis, surgical management, and clinical follow-up of this disease.We retrospectively reviewed 164 patients with PTs who underwent surgical treatment at the Department of Surgery, Samsung Medical Center, Seoul, Korea, from January 1995 to July 2009. Clinical and histopathological data were analyzed.The median follow-up period was 33.6 months (range 2-179 months), and the median patient age was 43 years (range of 11-72 years). Tumor size ranged from 1 to 30 cm, with a median of 6.1 cm. A total of 148 patients (90.2 %) received local or wide excisions. Mastectomies were performed in 16 patients (9.8 %). The pathologic diagnoses included 82 benign (50.0 %), 42 borderline (25.6 %), and 40 malignant PTs (24.4 %). The tumor border was infiltrating in 43 patients (26.2 %) and pushing in 116 patients (70.7 %). The resection margin was divided by based on the width. Local recurrence was observed in 31 patients (18.9 %), and distant metastasis developed in four patients with malignant PTs. Risk factors for the local recurrence of a PT were a positive resection margin (P =.029) and tumor size (P =.001).The presence of tumor cells on the resection margin was a strong prognostic factor for local recurrence of PTs. However, a 1 cm negative margin thickness did not confer any local control advantage over a thinner negative margin width.

The optimal threshold of surgical margins for breast malignant phyllodes tumors (MPTs) and the impact of adjuvant chemotherapy and radiotherapy were investigated.We conducted a multicenter nationwide retrospective study of all MPT cases with central pathological review within the French Sarcoma Group. Endpoints were local recurrence-free survival (LRFS), metastasis-free survival (MFS), and overall survival (OS) rates.Overall, 212 patients were included in the study. All non-metastatic patients underwent primary surgical treatment, including 58.6% of conservative surgeries. An R0 resection was achieved in 117 patients (59.4%: 26.9% of patients with 1-2 mm margins, 12.2% of patients with 3-7 mm margins, 20.3% of patients with ≥ 8 mm margins). Ninety-four patients (45%) underwent a second surgery (SS) to obtain R0 margins, with a final mastectomy rate of 72.6%. Radiotherapy and chemotherapy were performed in 91 (43.1%) and 23 patients (10.9%), respectively, but were not associated with better outcomes. Mastectomy was significantly associated with better LRFS (p < 0.001). Margins of 0, 1, or 2 mm with SS were associated with better MFS (hazard ratio [HR] 0.3, p = 0.005) and OS (HR 0.32, p = 0.005) compared with margins of 0-1-2 mm without SS. Wider margins (> 8 mm) were not superior to margins of 3-7 mm (3-7 mm vs. > 8 mm; HR 0.81, p = 0.69). Age (HR 2.14, p = 0.038) and tumor necrosis (HR 1.96, p = 0.047) were found to be poor prognostic factors and were associated with MFS.This study suggests that 3 mm margins are necessary and sufficient for surgical management of MPTs, and emphasizes the importance of SS to obtain clear margins in case of 0-1-2 mm margins. No impact of adjuvant chemotherapy or radiotherapy was detected in this study.

Malignant phyllodes tumor of the breast (MPTB) is a kind of rare tumor. Our objective was to investigate the role of adjuvant radiotherapy (RT) in MPTB patients.

As the efficacy of radiotherapy and chemotherapy for treatment of phyllodes tumors (PTs) remains unclear, this study aimed to review all available data and evaluate the roles of radiotherapy and chemotherapy in PT treatment.We performed a comprehensive search of databases, including PubMed, Web of Science and the Cochrane Library. The outcomes of interest included the local recurrence (LR) rate, metastasis rate, disease-free survival rate and overall survival rate.Seventeen studies enrolling 696 patients were included in this random effect meta-analysis. Subgroup analysis and meta-regression were also conducted to determine study heterogeneity. A pooled local recurrence rate of 8% (95% CI: 1-22%) was observed with a statistical heterogeneity of I = 86.6% (p < 0.01) for radiotherapy. This was lower than the recurrence rate of 12% for simple surgical treatment (95% CI: 7-18%). Meta-regression analysis found that surgical margin status was the main source of heterogeneity (p = 0.04). The metastasis rate of 4% (95% CI: 0-11%) for patients receiving radiotherapy without significant heterogeneity was also lower than the rate for the simple surgery group (8, 95% CI: 3-15%). The available data for chemotherapy were too limited to support meta-analysis. Accordingly, we offer a pure review of these data.Our findings suggest that radiotherapy is effective in achieving local disease control and preventing metastasis.

To define a predictive model for clinical behaviour of breast phyllodes tumours (PT) using histological parameters and surgical margin status.

The prognosis of breast phyllodes tumors (PTs) largely depending on the pathological grading, which lacks objectivity. This study aimed to develop a nomogram based on clinicopathological features to evaluate the recurrence probability of PTs following surgery.Data from 334 patients with breast PTs, who underwent surgical treatment at Sun Yat-sen Memorial Hospital from January 2005 to December 2014, were used to develop a prediction model. Additionally, data of 36 patients from Peking University Shenzhen Hospital (cohort 1) and data of 140 patients from Sun Yat-sen University Cancer Center (cohort 2) during the same period were used to validate the model. The medical records and tumor slides were retrospectively reviewed. The log-rank and Cox regression tests were used to develop a clinical prediction model of breast PTs. All statistical analyses were performed using R and STATA.Of all 334 patients included in the primary cohort, 224 had benign, 91 had borderline, and 19 had malignant tumors. The 1-, 3-, and 5-year recurrence-free survival was 98.5%, 97.9%, and 96.8%, respectively. Ultrasound-guided vacuum-assisted biopsy (UGVAB) is a non-inferior treatment application in benign PTs compared with open surgery [hazard ratio (HR), 2.38; 95% confidence interval (CI), 0.59-9.58]. Width of surgical margin, mitoses, and tumor border were identified as independent risk factors for breast PTs. A nomogram was developed based on these three variables. The C-index of internal and external validation was 0.71, 0.67 (cohort 1) and 0.73 (cohort 2), respectively.The study model presented more concise and objective variables to evaluate the recurrence-free survival of patients after surgery, which can help deciding whether to do a re-excision or "wait and watch".2020 Annals of Translational Medicine. All rights reserved.