De-escalating indications for excision when breast core needle biopsy returns fibroepithelial lesion-not further characterized.

PURPOSE: Surgical excision is often performed to exclude phyllodes tumor (PT) when Core Needle Biopsy (CNB) of the breast returns fibroepithelial lesion-not further characterized (FEL-NFC). If imaging or CNB pathology features can be identified that predict a very low probability of borderline/malignant PT, thousands of women could be spared the expense and morbidity of surgical excisions. METHODS: This retrospective cohort study includes 180 FEL-NFC from 164 patients who underwent surgical excisional biopsy. RESULTS: The upgrade rate from FEL-NFC to benign PT was 15%, and to borderline/malignant PT 7%. Imaging features predicting upgrade to borderline/malignant PT included greater size (p = 0.0002) and heterogeneous echo pattern on sonography (p = 0.117). Histologic features of CNB predicting upgrade to borderline/malignant PT included "pathologist favors PT" (p = 0.012), mitoses (p = 0.014), stromal overgrowth (p = 0.006), increased cellularity (p = 0.0001) and leaf-like architecture (p = 0.077). A three-component score including size > 4.5 cm (Size), heterogeneous echo pattern on sonography (Heterogeneity), and stromal overgrowth on CNB (Overgrowth) maximized the product of sensitivity x specificity for the prediction of borderline/malignant PT. When the SHO score was 0 (72% of FEL-NFC) the probability of borderline/malignant PT on excision was only 1%. CONCLUSION: The combination of size ≤ 4.5 cm, homogeneous echo pattern, and absence of stromal overgrowth is highly predictive of a benign excision potentially sparing most patients diagnosed with FEL-NFC the expense and morbidity of a surgical excision.

"Growing fibroadenoma": Are there clinical and pathological features predicting a phyllodes tumor on surgical excision?

In cases of growth of FA on imaging, core needle biopsies (CNB) are often performed to rule out phyllodes tumor (PT). We aim to focus on "growing FAs" and to identify clinical and histopathologic features that are likely to predict a PT on excision. Thirty-four FAs with radiologic documentation of growth were included. Various clinical and pathological features such as age, body mass index (BMI), lesion size, and growth rate were recorded. On excision, 17 cases (50 %) were FAs, whereas 16 (47 %) were re-classified as benign PT despite only 19 % being suspicious for PT on CNB. PT patients were older (mean age 42.6) than those with FAs (mean age 28.2), p = 0.0002. All false negative cases demonstrated intracanalicular growth. Mitotic rate was the most significant histologic feature in PT on excision compared to others, such as lesion circumscription and stromal cellularity. Recognition and careful counting of mitotic rate, especially with intracanalicular patterns in growing FAs, can potentially prevent missing a PT on CNB. In patients with "growing FAs" who are ≥40 years of age, excision may be recommended due to the high likelihood of PT diagnosis on excision and high false negative rate on CNB.

Imaging and management of fibroepithelial breast lesions on percutaneous core needle biopsy.

The purpose of this study is to review the clinical presentation, multi-modality appearance, and management of the most common benign and malignant fibroepithelial lesions of the breast. Fibroepithelial lesions of the breast may exhibit characteristic features on mammography, ultrasound, and MRI, although definitive diagnosis most often requires biopsy and at times, surgical excision. Knowledge of the imaging features can assist in refining the differential diagnosis and guiding appropriate management.

Accuracy and clinical implications of pre-operative breast core needle biopsy diagnoses of fibroepithelial neoplasms and sarcomatoid carcinomas.

PURPOSE: Accurate classification of breast phyllodes tumors (PTs) on core biopsy can be challenging. The differential diagnosis of benign PT (BP) is fibroadenoma (FA), whereas the differential diagnosis of malignant PT (MP) is sarcomatoid (metaplastic) carcinoma (SC). METHODS: Here, we compare the pre-excision core biopsy diagnosis and clinicopathologic features of histologically confirmed MP, borderline PT (BLP), BP, FA, and SC. Consecutive cases of 34 histologically confirmed PT (14 MP, 10 BLP, 10 BP), 13 SC, and 10 FA were identified. RESULTS: A core biopsy diagnosis of SC was made only in SC (77%, p = 0.003). The diagnosis "malignant neoplasm" or "atypical spindle cell neoplasm" was made in 100% MP and 23% SC, but no other tumor (p = 0.0001). The diagnosis "phyllodes tumor" was made only in PT (44% BLP, 11% BP, p = 0.06). The diagnosis "fibroepithelial lesion" was made in 44% BLP, 67% BP, and 29% FA. The diagnosis "FA" was made most commonly in FA (57%) (versus 22% BP and no other tumor; p = 0.002). Neoadjuvant therapy was given only in SC (23%, p = 0.03); adjuvant therapy was given in 46% SC and 13% MP (p = 0.04). CONCLUSIONS: A pre-operative core biopsy diagnosis of "malignant spindle cell neoplasm" separates MP and SC from BLP, BP, and FA. However, MP and SC can have overlapping features on core biopsy. Thus, one must be careful not to overcall SC on core biopsy, as patients diagnosed with SC may receive neoadjuvant therapy. A core biopsy diagnosis of "phyllodes tumor" is specific for PT and can guide treatment planning of a wide local excision.

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.

Is excision biopsy of fibroadenomas based solely on size criteria warranted?

Fibroadenomas (FA) are the most common benign tumor in the female breast. Most are managed conservatively provided there is clinical, radiologic, and pathologic concordance. However, surgical excision is typically recommended for cellular fibroepithelial lesions or those lesions with clinical, radiologic, or pathologic features concerning for phyllodes tumor (PT). Some studies have suggested surgical excision in all FA >30 mm to reduce core needle biopsy (CNB) sampling errors. The aim of our study was to evaluate, in the absence of any other concerning clinicopathologic features, whether surgical excision of FA was warranted based on size criteria alone. Cork University Hospital is a large academic center in Southern Ireland. Its breast cancer center provides both a screening and symptomatic service and diagnoses approximately 600 cancers per year. The breast histopathological data base was reviewed for all CNBs from January 1, 2010, to June 30, 2015, with a diagnosis of FA that went on to have excision at our institution. We excluded all cellular fibroepithelial lesions and those cases with co-existent lobular neoplasia, ductal carcinoma in situ, invasive carcinoma, atypical ductal hyperplasia, or lesions which would require excision in their own right. Cases in which the radiologic targeted mass was discordant with a diagnosis of FA were also excluded. Patient demographics and preoperative radiologic size and the radiologic target were recorded in each case. All radiology was reviewed by a breast radiologist prior to inclusion in the study, and there was histologic radiologic concordance with a diagnosis of FA in all cases. A total of 12,109 consecutive radiologically guided CNB were performed January 2010-June 2015; 3438 with a diagnosis of FA were identified of which 290 cases went on to have surgical excision. Of those 290 cases; 98.28% (n = 285) were confirmed as FA on excision. The remaining 1.72% (n = 5) had atypical features-FA with LCIS (n = 1), benign PT (n = 3), and invasive ductal carcinoma (n = 1). Our study suggests that, excision based solely on size is not warranted in clinical and radiologically concordant cases with a diagnosis of FA on CNB.

Fibroepithelial Neoplasm with Hybrid Features of Benign Phyllodes Tumor, Juvenile Papillomatosis, and Juvenile Fibroadenoma: A Case Report.

Phyllodes tumor is an uncommon breast fibroepithelial neoplasm mainly found in middle-aged patients, presenting a morphologic continuum from benign to malignant. Juvenile papillomatosis represents a rare benign proliferative breast tumor primarily affecting young individuals and carries a potential elevated risk of subsequent breast cancer development. Juvenile fibroadenoma is a well-circumscribed biphasic neoplasm that often occurs in adolescent girls, characterized by a pericanalicular growth pattern with usual-type epithelial hyperplasia and gynaecomastia-like micropapillary proliferation. Herein, we present an unusual example of a 26-year-old woman with a left breast outer lower quadrant palpable mass. Ultrasonography identified a 5.9 cm lobulated hypoechoic solid mass with scattered small cysts. The preoperative biopsy initially diagnosed a fibroepithelial lesion, considering giant cellular fibroadenoma and phyllodes tumor in the differential. Subsequent complete excision revealed areas of benign phyllodes tumor features closely admixed with distinctive elements such as prominent multiple cysts exhibiting apocrine and papillary apocrine metaplasia, duct papillomatosis, and duct stasis characteristic of juvenile papillomatosis, and hyperplastic ductal epithelium with micropapillary projections demonstrating a pericanalicular growth pattern indicative of juvenile fibroadenoma. The diagnosis was conclusively established as a fibroepithelial lesion with combined features of benign phyllodes tumor, juvenile papillomatosis, and juvenile fibroadenoma. Further investigation uncovered a family history of breast cancer. Molecular analysis revealed a pattern of unique and overlapping mutations within these distinct histopathological areas. This unusual presentation with hybrid features within a single tumor is described for the first time in the literature along with the molecular signature of the individual components.

Fibroepithelial Lesion Spectrum: A Case Report Documenting a Possible Transformation to a Malignant Phyllodes Tumor.

We discuss the radiological-pathological aspects of a rare case of transformation of a presumed fibroadenoma (FA) to a malignant phyllodes tumor (PT) and review the literature. Phyllodes tumors often show heterogeneous histologic features with some areas indistinguishable on core needle biopsy. A core biopsy is often a small representation of a larger lesion. As such, a complete excisional biopsy is often needed for a definitive pathologic diagnosis. Careful clinical and imaging correlation and follow-up are necessary, even in a benign fibroepithelial lesion (FEL).

Fibroadenoma vulva: Experience based on FNA of vulvar lesion.

Vulval fibroadenoma is an extremely rare lesion, mostly seen in young adults. A 51-years-old woman presented with a painless, mobile, and pedunculated vulval mass. Fine-needle aspiration (FNA) was performed and was diagnosed as a benign fibroepithelial lesion possibly fibroadenoma vulva, which was later confirmed as fibroadenoma vulva histopathologically. It is just not rare to find fibroadenoma vulva, but this should also be kept as a differential when diagnosing such cytomorphology in FNA lesions. This is important to avoid unnecessary incisional biopsy before excision.

Race-Related Differences in the Clinical Presentation and Histopathologic Features of Phyllodes Tumor.

BACKGROUND: Phyllodes tumor (PT) is a rare fibroepithelial lesion of the breast with variable malignant potential. Black women have a higher incidence of a related benign tumor, fibroadenoma, but there are limited epidemiological data on PT. The aim of our study was to evaluate race-related differences in the clinicopathologic features and outcomes of PT. METHODS: Our institutional pathology database was queried for breast specimen reports from 01/2009 to 10/2019 to identify patients with a pathologic diagnosis of PT. Chart review and detailed slide review were performed to obtain clinical and histopathologic variables, respectively. RESULTS: Among twelve patients, two had malignant PT, three had borderline PT, and seven had benign PT. All patients with malignant and borderline PT were black, compared with 29% of those with benign PT. There were no apparent race-related differences in specific histopathologic features among black vs. non-black women with benign PT. Malignant and borderline PT were relatively larger than benign PT, with mean tumor sizes of 9.0 cm (standard deviation [SD] 4.7 cm), 12.2 cm (SD 9.4 cm), and 5.4 cm (SD 5.8 cm), respectively. Two women had a local recurrence, both of whom were black. DISCUSSION: In this single-institution retrospective study, we observed disproportionate rates of aggressive histopathologic features and disparate outcomes among black women with PT. A multi-institutional PT registry would facilitate improved knowledge about race-related differences in the presentation and outcomes of this rare tumor.

Clinicopathological Parameters Predicting Malignancy in Phyllodes Tumor of the Breast.

Introduction Phyllodes tumor (PT) is an uncommon fibroepithelial neoplasm of the breast. It is a biphasic tumor with stromal and epithelial components, with a tendency to recur. Because of its wide range of disease manifestations, it has been subclassified into three categories, i.e., benign, borderline, and malignant, based on several histological parameters. This study was conducted to evaluate the clinicopathological features associated with malignancy in breast PTs. Methods We conducted a retrospective study at the Department of Histopathology at Liaquat National Hospital, Karachi, Pakistan. A total of 146 biopsy-proven cases of PTs were enrolled in the study. Clinical data were obtained from the clinical referral forms. Specimens were obtained from either lumpectomy or simple mastectomy. The specimens obtained were received at the laboratory where after gross examination, paraffin-embedded tissue blocks were prepared, which were sectioned, stained, and studied by a senior histopathologist. Pathological features, such as mitotic count, necrosis, stromal atypia, stromal overgrowth, and heterologous elements, were observed. Based on these features, the PTs were classified into benign, borderline, and malignant tumors. Results The mean age of the PTs in our setup was 40.65 ± 12.17 years with a mean size of 9.40 ± 6.49 cm. Malignant PT was found to be the most prevalent in our population, accounting for 63 (43.2%) cases, followed by borderline (51, 34.9%) and benign (32, 21.9%). A significant association was found between the tumor subtype and patient age, i.e., patients diagnosed with malignant and borderline PTs were found to be of older age (mean 42.82 ± 12.94 and 42.05 ± 11.31 years, respectively) than those diagnosed with benign PTs (mean age 34.12 ± 9.75 years). Moreover, malignant PTs were associated with larger tumor size (mean 11.46 ± 6.08) compared with the other two subtypes. Conclusion We found a significant association among patient age, tumor size, and PT subtype. Therefore, apart from the usual histological parameters, patient age and tumor size are important parameters for predicting the behavior of breast PT and should be considered for management.

Complex Fibroadenoma with Pronounced Squamous Metaplasia: A Rare Case Report, Differential Diagnostic Considerations, and Associated Breast Cancer Risk.

Squamous metaplasia of the breast is a rare and unusual finding. A number of benign and malignant differential entities exist when squamous cells are present in a breast lesion. Our patient was found to have pronounced squamous metaplasia and keratin cysts arising in a complex fibroadenoma. The rare nature of squamous metaplasia arising in such a lesion poses some diagnostic challenges, as squamous epithelium and squamous metaplasia in the breast may raise suspicion for malignancy. Herein we present a unique case and discussion of benign and malignant differential entities. We also retrospectively reviewed a series of complex fibroadenomas in our institution, including the demographic and histologic features, and more importantly the associated breast cancer risk.

Radiologic-Pathologic Correlation of Fibroepithelial Lesions: A Pictorial Review.

Fibroepithelial lesions (FEL) of the breast encompass a spectrum of masses ranging from benign to malignant. Although these lesions are on the same biologic spectrum, differences in their clinical behaviors necessitate different management approaches. While imaging features are nonspecific, small size (less than 3 cm), oval shape, circumscribed margins, growth in diameter less than 20% in six months, and homogeneous echotexture on US favor fibroadenoma (FA). Conversely, larger size (3 cm or larger), rapid growth, irregular shape, noncircumscribed margins, and heterogeneous echotexture suggest possible phyllodes tumor (PT). Histopathologically, increased stromal cellularity, stromal atypia, and mitotic activity characterize PT, while FA typically lack these features. In this review, we summarize the imaging and pathology characteristics of nonmalignant FEL, including simple, juvenile, and complex FA, and benign and borderline PT and highlight the collaborative role of radiologists and pathologists in informing diagnosis and clinical management.

Transformation of a Benign-Appearing Fibroepithelial Lesion to a Giant Malignant Phyllodes Tumor of the Breast.

This is a case of a woman who presented with a left breast mass that was initially diagnosed as fibroadenoma on core biopsy and, after three years without any surgical intervention, was found to be a malignant phyllodes tumor. Initially, a core needle biopsy of the mass showed probable fibroadenoma. Because of the initial benign seeming diagnosis and the need to treat her tongue cancer, the patient did not recognize the need for a recommended surgical consultation and excision. Three years later, she presented after the mass had enlarged to encompass nearly the whole left breast. Core needle biopsy revealed spindle cell proliferation with scattered benign-looking tubules. Due to the large size of the mass, she underwent a total mastectomy, and the final pathology demonstrated a malignant phyllodes tumor. This case demonstrates a case of progression of a benign-appearing fibroepithelial lesion to a malignant phyllodes tumor three years later.

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.

Diagnosis on Excision Biopsy of Breast Tissues Labeled As Fibroepithelial Tumors on Trucut Samples in a Developing Country.

INTRODUCTION: Fibroadenomas (FAs) and phyllodes tumors (PTs) are less prevalent but allied to have malignant transformation in many instances. It is a challenge to diagnose the phyllodes by conventional trucut biopsy technique. OBJECTIVE: To evaluate the histological characteristics of tumors labeled as fibroepithelial lesions of breast tissues on trucut biopsy and compare with a diagnosis on excision biopsy. METHODS AND MATERIALS: It was a descriptive cross-sectional study that was carried out in Shaukat Khanum Memorial Hospital and Research Centre within six years from January 2015 to January 2021. In trucut samples, stromal cellularity, stromal cell nuclear atypia, mitotic count, stromal overgrowth, the enhancement of stromal cellularity adjacent to epithelium were scrutinized. In each category, the activity was seen as absent, mild, moderate, or severe. Mitotic activity was graded as 0-1, 0-5, 5-10, >10. RESULTS: A total of 125 patients were registered for the study. The mean age of patients in our study was 33.86 ± 9.95 years. The mean size was 41.02 ± 27.38 mm with a mean lump duration of 7.52 ± 5.34 months. In the FA group, the trucut sampling report showed the stromal cellularity as mild in 62 (69.7%) and stromal cell nuclear atypia as absent in 68 (76.4%) cases. But in the phyllodes tumor group, the stromal cellularity was severe in 10 (27.8%) patients and stromal cell nuclear atypia was severe in five (13.9%). The ultimate outcome showed that 89 (71.2%) patients had FA and 36 (28.8%) had PT at excision. CONCLUSION: Assessment of tumor size, stromal cellularity, mitoses, and enhancement of stromal cellularity adjacent to epithelium are useful markers for diagnosing the PT in trucut needle biopsy.

Keratin cyst as a diagnostic pitfall in aspiration cytology of phyllodes tumor.

BACKGROUND: Phyllodes tumor (PT) is a fibroepithelial lesion of breast known for presence of a heterogenous stroma. However occurrence of a keratin cyst within PT is a rare incidence. An inadequate sampling during fine needle aspiration (FNA) of such lesions may result in an erroneous cytological diagnosis. CASE REPORT: In the present case, ultrasound guided FNA smears from the breast lump in a 31-year-old lady with a clinical suspicion of malignancy, were repeatedly interpreted as an epidermal inclusion cyst, which was ultimately reported as a borderline PT on mastectomy. CONCLUSION: The case report aims at highlighting the importance of a diligent FNA technique keeping in mind the possibility of the various uncommon lesions especially while dealing with such a heterogenous tumor as phyllodes.

Recurrent myoid hamartoma of the breast mimicking malignancy.

Myoid (muscular) hamartoma is a rare form of benign breast hamartoma composed of differentiated mammary glandular and stromal structures, fatty tissue and areas of smooth muscle from which its name originates. It is considered to be a variant of a mammary hamartoma. We report the clinical presentation, imaging appearances and treatment of the initial and recurrent presentation of this rare tumour in a 61year old female, which mimicked malignancy.  Although rare, myoid hamartoma's can reoccur and when they do they imaging appearances of benign and malignant tumours can overlap tend to mimic malignancy and histological diagnosis is mandatory.

Phyllodes Tumor of the Breast: A Clinicopathological Evaluation of 55 Cases.

OBJECTIVE: Phyllodes tumors are biphasic tumors consisting of epithelial and stromal components that account for less than 1% of all breast tumors. According to the World Health Organization (WHO) phyllodes tumors are classified into three categories as benign, borderline and malignant. It has been reported that these tumors are usually benign and both the stromal component and the epithelial component may progress to malignancy. In this descriptive study, it was aimed to present the cases of phyllodes tumor and to evaluate the clinicopathological features of these tumors in the light of the literature. MATERIALS AND METHODS: In our study, 55 cases of phyllodes tumor diagnosed between 2005-2018 in the Department of Medical Pathology were retrospectively studied. A total of 55 cases were included in the study. RESULTS: All cases were female with a mean age of 39.7+15.2 years. Fifty-seven tumors diagnosed in 55 cases were classed as benign in 20 cases (35.1%), borderline in 14 cases (24.6%) and malignant phyllodes tumors in 23 cases (40.3%). Ductal carcinoma in situ (solid and cribriform type) were detected in one case with malignant phyllodes tumor, whereas invasive ductal carcinoma was detected in one case. Bilateral ductal carcinoma in situ was present in the patient with invasive ductal carcinoma. CONCLUSION: These tumors which rapidly grow into large masses can be clinically and pathologically confused with benign lesions, macroscopic and microscopic evaluation of concomitant in situ-invasive carcinomas should be considered. Phyllodes tumors have an important role in breast surgery and pathology.