Fibroadenoma versus phyllodes tumor: a vexing problem revisited!

Rapid Onsite Evaluation for Specimen Adequacy and Triage of Breast Masses in a Low-Resource Setting

CONTEXT.—

Rapid onsite evaluation (ROSE) is critical in determining sample adequacy and triaging cytology samples. Although fine-needle aspiration biopsy (FNAB) is the primary method of initial tissue sampling in Tanzania, ROSE is not practiced.

OBJECTIVE.—

To investigate the performance of ROSE in determining cellular adequacy and providing preliminary diagnoses in breast FNAB in a low-resource setting.

DESIGN.—

Patients with breast masses were recruited prospectively from the FNAB clinic at Muhimbili National Hospital. Each FNAB was evaluated by ROSE for overall specimen adequacy, cellularity, and preliminary diagnosis. The preliminary interpretation was compared to the final cytologic diagnosis and histologic diagnosis, when available.

RESULTS.—

Fifty FNAB cases were evaluated, and all were adequate for diagnosis on ROSE and final interpretation. Overall percentage of agreement (OPA) between preliminary and final cytologic diagnosis was 84%, positive percentage of agreement (PPA) was 33%, and negative percentage of agreement (NPA) was 100% (κ = 0.4, P < .001). Twenty-one cases had correlating surgical resections. OPA between preliminary cytologic and histologic diagnoses was 67%, PPA was 22%, and NPA was 100% (κ = 0.2, P = .09). OPA between final cytologic and histologic diagnoses was 95%, PPA was 89%, and NPA was 100% (κ = 0.9, P = <.001).

CONCLUSIONS.—

False-positive rates of ROSE diagnoses for breast FNAB are low. While preliminary cytologic diagnoses had a high false-negative rate, final cytologic diagnoses had overall high concordance with histologic diagnoses. Therefore, the role of ROSE for preliminary diagnosis should be considered carefully in low-resource settings, and it may need to be paired with additional interventions to improve pathologic diagnosis.

Fibroadenoma in axillary breast tissue - Utility of rapid on-site evaluation & report of two cases

ABSTRACT

Fibroadenoma of axillary breast tissue presents as a palpable mass, cyclic pain in the axilla, and with asthetic concerns. Axillary breast tissue can occur anywhere along the primitive embryonic milk lines, extending from the axilla to the groin, and can present unilaterally or bilaterally. The reported incidence of axillary breast tissue is 0.4%-6% in females. We had two cases of fibroadenoma in the axilla that were diagnosed on rapid on-site evaluation and later confirmed by routine cytology stains in young females. We report the cases for their rarity and high degree of clinical suspicion in the young reproductive age group female. We also emphasize the utility of ROSE in cytopathology.

The Diagnostic Significance of the BI-RADS Classification Combined With Automated Breast Volume Scanner and Shear Wave Elastography for Breast Lesions

OBJECTIVE

We herein compared the diagnostic accuracy of the BI-RADS, ABVS, SWE, and combined techniques for the classification of breast lesions.

METHODS

Breast lesions were appraised using the BI-RADS classification system as well as the combinations of BI-RADS plus ABVS (BI-RADS + ABVS) and BI-RADS plus SWE (BI-RADS + SWE), and both methods (BI-RADS + ABVS + SWE) by two specialties Medical Ultrasound physician. The Fisher's exact and χ² tests were performed to compare the degree of malignancy for the various methods with a pathology ground truth. Receiver operating characteristic curves (ROC) were generated and the corresponding area under the curve (AUC) values were determined to test the diagnostic efficacy of the various methods and identify the optimal SWE cut-off indicative of malignancy.

RESULTS

The incidence of the retraction phenomenon on ABVS images of the malignant group was significantly higher (P < .001) than that of the benign group. The specificity, sensitivity, and positive and negative predictive values of the BI-RADS classification were 88.72, 79.38, 83.70, and 85.50%, respectively. BI-RADS plus SWE-Max exhibited enhanced specificity, sensitivity, and positive and negative predictive values of 88.72, 92.78, 85.70, and 94.40%, respectively. Similarly, when BI-RADS + ABVS was utilized, the sensitivity and negative predictive value increased to 95.88 and 96.40%, respectively. BI-RADS + ABVS + SWE possessed the highest overall sensitivity (96.91%), specificity (94.74%), and positive (93.10%) and negative (97.70%) predictive values from all four indices.

CONCLUSION

ABVS and SWE can reduce the subjectivity of BI-RADS. As a result, BI-RADS + ABVS + SWE resulted in the best diagnostic accuracy.

Differentiation between Phyllodes Tumors and Fibroadenomas through Breast Ultrasound: Deep-Learning Model Outperforms Ultrasound Physicians

The preoperative differentiation of breast phyllodes tumors (PTs) from fibroadenomas (FAs) plays a critical role in identifying an appropriate surgical treatment. Although several imaging modalities are available, reliable differentiation between PT and FA remains a great challenge for radiologists in clinical work. Artificial intelligence (AI)-assisted diagnosis has shown promise in distinguishing PT from FA. However, a very small sample size was adopted in previous studies. In this work, we retrospectively enrolled 656 breast tumors (372 FAs and 284 PTs) with 1945 ultrasound images in total. Two experienced ultrasound physicians independently evaluated the ultrasound images. Meanwhile, three deep-learning models (i.e., ResNet, VGG, and GoogLeNet) were applied to classify FAs and PTs. The robustness of the models was evaluated by fivefold cross validation. The performance of each model was assessed by using the receiver operating characteristic (ROC) curve. The area under the curve (AUC), accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were also calculated. Among the three models, the ResNet model yielded the highest AUC value, of 0.91, with an accuracy value of 95.3%, a sensitivity value of 96.2%, and a specificity value of 94.7% in the testing data set. In contrast, the two physicians yielded an average AUC value of 0.69, an accuracy value of 70.7%, a sensitivity value of 54.4%, and a specificity value of 53.2%. Our findings indicate that the diagnostic performance of deep learning is better than that of physicians in the distinction of PTs from FAs. This further suggests that AI is a valuable tool for aiding clinical diagnosis, thereby advancing precision therapy.

Prevalence, Impact, and Diagnostic Challenges of Benign Breast Disease: A Narrative Review

Benign breast diseases, which are commonly seen in clinical practice, have various clinical presentations and implications, as well as management strategies. This article describes common benign breast lesions, presentations of these lesions, and typical radiographic and histologic findings. Also included in this review are the most recent data and guideline-based recommendations for the management of benign breast diseases at diagnosis, including surgical referral, medical management, and ongoing surveillance.

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 of the breast; incidence of malignancy and indicators for surgical intervention: An analysis of 1392 patients

BACKGROUND

Fibroadenomas are common among young females. The size of the lesion used to be an indication for further assessment or excision. With arising of the watch and see proponents, criteria for selecting patients are important to establish.

METHODS

This is a retrospective study of a prospectively maintained database where all patients having the clinical/radiological provisional diagnosis of fibroadenoma and attending our center - from January 2008 to March 2020 - were enrolled. The primary outcome was the incidence of malignancy and the secondary outcomes were the correlation of malignancy-risk with epidemiologic and radiologic criteria.

RESULTS

The study enrolled 1392 patients. The mean age of the patients was 35.7 + ∕- 13.1 years. The median of the longest diameter of the detected breast lesions was 25 mm. The incidence of malignancy was 188 (13.5%). The size of the lesion measured by largest diameter was insignificant (p = 0.99), while the patients' age, marital status, and imaging criteria as measured by BIRADS score were significant (<0.001).

CONCLUSION

Approaching patients with the age above 35 or with BIRADS 4 provisionally diagnosed with fibroadenomas should be cautious with biopsy and short-term follow-ups The size of the tumor alone should not be used as an indication for surgical intervention.

Native T1 mapping of the breast in MRI to differentiate fibroadenomas from benign phyllodes tumors: a preliminary study

OBJECTIVE

Both fibroadenomas (FAs) and phyllodes tumors (PTs) are classified as fibroepithelial lesions. PTs are rare fibroepithelial neoplasms that have a morphologic spectrum ranging from benign to malignant. The differentiation of these entities is important as PTs are to be enucleated surgically. The purpose of this study was to calculate the T1 relaxation times of fibroadenomas and phyllodes tumors and assess the potency of native T1 mapping for the differentiation of these tumors.

MATERIALS AND METHODS

This prospective study included 11 patients with a proven diagnosis of benign PT and 14 patients with a proven diagnosis of FA. All the patients underwent T1 mapping prior to conventional dynamic contrast-enhanced MRI (DCE-MRI). Two radiologists, in consensus, selected lesion locations using freehand regions of interest from the DCE images and copied them onto T1 maps to acquire T1 relaxation times. The T1 relaxation times of the FA and PT groups were compared statistically.

RESULTS

The mean T1 relaxation times were higher in the PT group compared to the FA group (p ≤ 0.001). The receiver operating characteristic analysis showed that the T1 relaxation time being longer than 1,478 ms differentiated PTs from FAs with a sensitivity of 0.89, specificity of 1, and area under the curve value of 0.93.

CONCLUSION

We found that benign PTs had longer relaxation times in T1 mapping compared to FAs. Native T1 mapping can be used to differentiate PTs from FAs and adding T1 mapping in breast MRI in cases with fast-growing fibroepithelial lesions or multiple fibroepithelial lesions can facilitate the decision-making process.

Upstaging of Fibroepithelial Lesions: A Single-Institution Experience

INTRODUCTION

Fibroepithelial lesions of the breast (FEL) are heterogeneous lesions ranging from fibroadenomas (FA) to phyllodes tumors (PT). FEL with cellular stroma are diagnostic challenges on core needle biopsy (CNB) as it is difficult to distinguish cellular FA from PT. The purpose of this study was to determine the features of FEL on CNB that may be predictive of PT, the upstage rate to PT after excision, and the outcomes of those who did not undergo excision.

METHODS

Overall, 305 patients with FEL on CNB between 2009 and 2019 were identified from a prospectively maintained institutional database. Presentation, imaging, and pathology were evaluated.

RESULTS

Mean age at diagnosis was 43.8 years. Pathology on CNB included 97 cases of FEL favoring FA, 19 cases of FEL favoring PT, 3 cases of FEL versus pseudoangiomatous stromal hyperplasia, and 186 cases of FEL not otherwise specified. Following CNB, 96 (31.5%) patients were observed, 158 (51.8%) patients had an excisional biopsy, 48 (15.7%) patients underwent segmental mastectomy, and 3 (1.0%) patients underwent a mastectomy. The upgrade rate from FEL on CNB to PT upon excision was 25.8%. PT on final pathology was more commonly seen when the CNB identified stromal overgrowth, necrosis, and diagnosis of FEL favoring PT. On multivariable analysis, a final diagnosis of PT was associated with age >50 years, larger tumor size >2 cm, stromal overgrowth, and ≥1 mitoses/10 high power fields (HPF) on CNB. Patients who were observed had smaller tumors compared with those who underwent excision.

CONCLUSION

In this 10-year single-institution experience of FEL, the upstage rate to PT was 25.8%. Excision of FEL is recommended. Furthermore, the observation of lesions appeared to be safe in select cases, specifically in patients with smaller tumor size.

Benign myofibroblastic/epithelial lesions of the breast with minimally infiltrative margins

A minority of mixed fibro-epithelial lesions of the breast lacks both fibroadenoma and phyllodes architectural patterns and have been previously labeled with different terms, including "hamartomas", "myoid/muscular hamartomas", "benign fibroadenomatous lesions" or "stromo-epithelial lesions of the breast". This study emphasizes the clinico-pathologic features of 5 cases of mammary benign fibro(stromo)-epithelial lesions sharing as a common morphologic theme the presence of minimally infiltrative margins due to the overgrowth of the stromal component into the surrounding fibro-fatty tissue. Notably the radiological features were suspicious for malignancy in 3 out of 5 cases. The following histologic features were seen in all cases: i) an epithelial component of benign glandular structures exhibiting the morphological spectrum of fibro-cystic disease; ii) a stromal component of bland-looking spindle cell myofibroblasts (vimentin + and α-smooth muscle actin +) set in a variably fibro-myxoid stroma. The present paper contributes to widen the morphological spectrum of the benign fibro-epithelial lesions of the breast, emphasizing the possibility that some cases, exhibiting a predominant myofibroblastic stromal component and minimally infiltrative margins, may be confused with other primary spindle cell mimickers of the breast. Accordingly, we propose the descriptive term "benign myofibroblastic/epithelial lesions of the breast with minimally infiltrative margins" for these previously underrecognized lesions.

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.

Accuracy of Breast Fine-Needle Aspiration Biopsy Using the International Academy of Cytology Yokohama System in Clinico-Radiologically Indeterminate Lesions: Initial Findings Demonstrating Value in Lesions of Low Suspicion of Malignancy

BACKGROUND

Fine-needle aspiration biopsy (FNAB) in breast lesions offers accurate results in differentiating benign and malignant lesions. However, its role is unclear when core-needle biopsy (CNB) is available, the latter providing additional information regarding tumor grade, invasion, and hormone receptor status in malignant lesions. In benign breast lesions, especially in BIRADS category 4a and 4b, FNAB, and CNB provide similar pathological information, whereby FNAB may serve as a more rapid and cost-effective investigation. The study was planned to reevaluate the diagnostic accuracy of FNAB in BIRADS category 4a, 4b, and 4c lesions.

MATERIALS AND METHODS

FNAB and biopsy reports of all patients with breast lesions sent between September 1, 2018, and November 30, 2020, were collected and the International Academy of Cytology (IAC) Yokohama category and BIRADS score were recorded for each case. The rate of malignancy and the accuracy of FNAB in diagnosing malignancy were calculated for each BIRADS 4a, 4b, and 4c subgroup.

RESULTS

A total of 249 cases of BIRADS 4 lesions had corresponding cytology and histopathology diagnoses. FNAB showed high diagnostic accuracy in all BIRADS groups. A benign categorization was associated with a very low number of false-negative diagnoses, especially in BIRADS 4a lesions.

CONCLUSION

The study reconfirms the excellent accuracy of breast FNAB using the IAC Yokohama system in diagnosing breast malignancies. Furthermore, BIRADS 4a lesions found to be belonging to the cytological benign category may be excluded from CRB and kept on clinical follow-up.

Implementation of the International Academy of Cytology Yokohama standardized reporting for breast cytopathology: An 8-year retrospective study

BACKGROUND

The International Academy of Cytology (IAC) Yokohama reporting system was recently proposed to serve as a standardized diagnostic platform for the cytological interpretation of breast fine needle aspiration biopsy (FNAB). Five cytological categories were suggested, linked to a certain risk of malignancy (ROM). The aim of this study was to assess the potency of this newly proposed reporting guideline, with a review of literatures.

METHODS

This is a retrospective study over 8-year duration in which all the breast FNABs performed in our institution were recategorized in accordance to the IAC Yokohama reporting system. Kappa coefficient was used to evaluate the agreement between the proposed cytological category and corresponding histological diagnosis, with the level of significance set at 5%. Cyto-histopathological correlation and its diagnostic performance were also assessed.

RESULTS

A total of 1136 breast FNABs were analyzed, including 31 repeat FNABs. Of these, 521 (47.1%) cases had matched histopathological results. Respective ROM for each category was: "insufficient" 13.6%, "benign" 0.4%, "atypical" 25.0%, "suspicious" 85.7%, and "malignant" 100%. There was substantial agreement (κ=0.757) between cytology and histopathological results. Our data revealed a high-diagnostic specificity, sensitivity, positive and negative predictive value of 99.3% (95% CI: 97.6%-99.9%), 94.2% (95% CI: 87.9%-97.9%), 98.0% (95% CI: 92.5%-99.5%), 98.0% (95% CI: 96.1%-99.1%) respectively when both the "suspicious" and "malignant" cases were considered as positive tests, with area under the curve of 0.993.

CONCLUSIONS

The IAC Yokohama system is a reliable, evidence-based, and standardized reporting system that helps to facilitate communication among cytopathologists, radiologists, and surgeons toward individualized patient management.