Prognostic factors in phyllodes tumours of the breast: retrospective study on 166 consecutive cases

Comprehensive Clinical-Pathologic Assessment of Malignant Phyllodes Tumors: Proposing Refined Diagnostic Criteria

The latest World Health Organization classification of breast tumors recommends diagnosing malignant phyllodes tumors (MPTs) when all 5 morphologic features are present: permeative borders, marked stromal cellularity, marked stromal cytologic atypia, ≥10 mitoses per 10 high-power fields (HPF), and stromal overgrowth. We assessed the performance of this recommendation to capture MPTs and features predictive of distant metastasis in a multi-institutional retrospective study. Of 65 MPTs, most cases had at least focally permeative borders (58, 89%), with marked stromal cellularity in 40 (61.5%), marked atypia in 38 (58.5%), ≥10 mitoses per 10 HPF in 50 (77%), and stromal overgrowth in 56 (86%). Distant metastases were observed in 20 (31%) patients (median follow-up 24.5 mo, 1 to 204). Only 13 of 65 (20%) cases had all 5 morphologic features, while only 7 of 20 (35%) cases with distant metastases had all 5 features. In univariate analysis, only marked stromal atypia ( P =0.004) and cellularity ( P =0.017) were associated with decreased distant metastasis-free survival. In multivariate Cox regression, the combination of stromal overgrowth, marked stromal cellularity, and atypia (C-index 0.721, 95% CI: 0.578, 0.863) was associated with decreased distant metastasis-free survival. The current World Health Organization recommendation will miss a significant number of MPTs with distant metastases. We propose refined diagnostic criteria for MPTs: (1) stromal overgrowth combined with ≥1 feature(s) (marked cellularity, marked atypia, or ≥10 mitoses per 10 HPF), or (2) in the absence of stromal overgrowth, marked cellularity combined with ≥1 feature(s) (permeative borders, marked atypia, or ≥10 mitoses per 10 HPF).

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.

Predicting the recurrence-free survival of phyllodes tumor of the breast: a nomogram based on clinicopathology features, treatment, and surgical margin

Background

Grading based on histopathologic indicators cannot accurately assess the prognosis of phyllodes tumor (PT) of the breast. This article aimed to investigate the correlation between PT prognosis and clinicopathological features, treatment, and surgical margin.

Methods

The clinicopathological data of patients with pathologically confirmed PT at our institution were retrospectively collected. Univariate and multivariate Cox proportional risk models were employed to test the effects of different variables on the prognosis of PT. A nomogram to predict the 1-, 3-, 5-, and 10-year recurrence-free survival (RFS) of PT was proposed, and its discriminative ability and calibration were tested using the concordance index (C-index), area under the curve (AUC), and calibration plots. All statistical analyses were performed using R.

Results

A total of 342 PT patients were included, including 242 benign (70.8%), 75 borderline (21.9%) and 25 malignant (7.3%) cases. The median follow-up period was 64.5 months (range, 3-179 months), 66 PT patients had local recurrence (LR), and four patients had distant metastasis. The 1-, 3-, 5-, and 10-year RFS of the PT patients were 90.8%, 81.8%, 78%, and 76.7%, respectively. Age, fibroadenoma (FA) surgery history, treatment, mitotic activity, and surgical margin were selected as the independent factors for PT prognosis. The nomogram showed good discriminative ability and calibration, as indicated by the C-index [0.78, 95% confidence interval (CI): 0.75-0.11].

Conclusions

Independent predictors related to PT prognosis were selected to establish a nomogram for predicting the RFS of PT. This nomogram was able to objectively stratify PT patients into prognostic groups and performed well in the internal validation.

Fibroepithelial Lesions of the Breast: Update on Molecular Profile With Focus on Pediatric Population

CONTEXT.—

This review article derives from the breast pathology lecture at the Eighth Princeton Integrated Pathology Symposium (PIPS VIII).

OBJECTIVE.—

To provide a literature review and update on fibroepithelial lesions of the breast with molecular findings and findings regarding the pediatric population.

DATA SOURCES.—

The sources include extensive literature review, personal research, and experience.

CONCLUSIONS.—

Given significant differences in prognosis and management of fibroepithelial lesions, we aim to provide readers with pertinent definitions, pathomorphology, molecular findings, and management for each diagnosis, with insights on the pediatric population.

Management of phyllodes tumor: A systematic review and meta-analysis of real-world evidence

BACKGROUND

Phyllodes tumor is rare but has a high recurrence rate. Treatment modalities and clinicopathological prognostic factors for recurrence remain unclear. The synthesis of real-world data can enable the integration of sufficient evidence on optimal treatment for this population.

METHODS

We searched PubMed, Embase, and Cochrane Library databases for studies focusing on the management of phyllodes tumor including the surgical margin, different clinicopathological prognostic factors, and postoperative adjuvant radiotherapy versus no radiotherapy.

RESULTS

Fifty-two studies were retrieved. The pooled estimated recurrence rates of benign, borderline, and malignant tumors were 7.1%, 16.7%, and 25.1%, respectively. Surgical margins of 1 mm (odds ratio [OR]: 0.4, 95% confidence interval [CI]: 0.27-0.61) and 1 cm (OR: 0.45, 95% CI: 0.15-0.85) resulted in significantly higher recurrence rates. Postoperative adjuvant radiotherapy significantly reduced the recurrence rate of malignant tumors relative to no radiotherapy (P = 0.034) but did not significantly reduce the recurrence rates of overall and borderline tumors. Regarding clinicopathological features, moderate or severe stromal atypia and hypercellularity, stromal overgrowth, mitotic number of 5, tumor necrosis, tumor border, and margin status were determined as independent prognostic factors for recurrence, except a tumor size of 5 cm.

CONCLUSION

The ideal surgical margin for phyllodes tumor incision should be at least 1 cm in width. Adjuvant radiotherapy reduced the recurrence of malignant tumor. By identifying patients with poor clinicopathological risk factors, surgeons may reduce the recurrence rate of phyllodes tumor.

Lymph Node and Distant Metastases in Phyllodes Tumor of the Breast

A 54-year-old woman who incidentally noticed a “knot” in her left breast subsequently underwent excisional biopsy which yielded a diagnosis of malignant neoplasm with sarcomatous features. Given the broad differential diagnosis and imaging findings, the patient underwent bilateral mastectomy and intraoperative sentinel lymph node assessment. An 8.5 cm tumor that was further classified as a malignant phyllodes tumor was identified in the left breast, while the frozen section interpretation came back as positive for metastatic disease which resulted in left axillary lymphadenectomy. Two months later the patient progressed to distant metastatic disease and unfortunately passed away within 6 months after her initial diagnosis. Lymph node metastasis in phyllodes tumor is an exceptionally rare event for which patients usually do not undergo intraoperative sentinel lymph node examination; however high clinical suspicion of metastatic disease would be evidence for further investigation.

The Defect Repair After a Giant Malignant Phyllodes Tumor Resection of Breast Using a Kiss Flap

Malignant phyllodes tumors of the breast are fairly rare and fast-growing tumors. They are not sensitive to chemotherapy or hormonal therapy. Therefore, the primary treatment for malignant phyllodes tumors is wide surgical excision. Herein, we report a case study which featured a 26-year-old woman presented with a giant malignant phyllodes tumor measuring 20 × 17 × 13 cm. In order to reduce the chance of local recurrence, treatment for these types of tumors usually involves extensive excision with at least 1 cm of surgical margins. The patient underwent mastectomy with negative surgical margins, which left a large skin defect of 25 × 15 cm. Repair of such a large skin defect is a challenge to breast surgeons. This is the first reported case in which a “kiss” flap was successfully used to repair the skin defect created after resection of a giant malignant phyllodes tumor. The kiss flap could be considered as an effective and simple method to repair large chest wall defects after resection of giant phyllodes tumors.

Surgical management and prognosis of phyllodes tumors of the breast

BACKGROUND

Regardless of histological grade, phyllodes tumors (PTs) exhibit the potential of local recurrence. The National Comprehensive Cancer Network (NCCN) recommends wide local excision (WLE) with a 1 cm margin or more for borderline/malignant PTs but excisional biopsy for benign PTs. However, the treatment of benign PTs remains controversial and the clinicopathologic risk factors for the local recurrence is still unclear.

METHODS

We retrospectively analyzed 238 patients with PTs who underwent surgery at the Chinese PLA General Hospital from January 1, 2006 and April 30, 2020. We stratified our analysis according to histologic grade and explored the clinicopathologic factors to influence local recurrence (LR), including age, histologic grade, history of fibroadenoma, type of surgery [vacuum-assisted biopsy system (VABS), local excision (LE), wide local excision (WLE) and mastectomy].

RESULTS

All 238 cases were categorized as benign (171, 71.8%), borderline (38, 16.0%), or malignant (29, 12.2%). The median follow-up was 50.2 months. In multivariate analysis, histologic grade (P<0.01) and history of fibroadenoma (P<0.01) were independent prognostic factors for LR. No difference existed in the recurrence rate of BPT treated with different surgical procedures (P=0.397), whereas a higher recurrence rate was found in VABS and LE subgroups than in WLE and mastectomy subgroups for borderline/malignant tumors (P<0.01).

CONCLUSIONS

No association found between surgical modalities and LR rate for BPT. We suggested a "wait-and-watch" policy for patients with unexpected benign subtypes, instead of unnecessary re-excision. In addition, VABS or LE can be treated for BPT with small mass, whereas WLE or even mastectomy should be conducted for borderline/malignant PTs with large mass.

Endoscopic features of esophageal high-grade intraepithelial neoplasia dominated by cytological atypia

Little is known about esophageal high-grade intraepithelial neoplasia dominated by cytological atypia (HGINc). We aimed to elucidate the endoscopic features of HGINc compared with esophageal high-grade intraepithelial neoplasia dominated by architectural atypia (HGINa). All patients pathologically diagnosed as esophageal high-grade intraepithelial neoplasia after endoscopic submucosal dissection at our center between January 2018 and December 2019 were included in this study. According to the pathological diagnosis, the patients were divided into two groups: HGINa group and HGINc group. Basic characteristics and endoscopic information were collected in detail. Data were analyzed statistically. Binary logistic regression was performed and a predictive model for HGINc was established. Then we evaluated its predictive value and built a nomogram for clinical application. A total of 175 patients were included in this study (126 with HGINa and 49 with HGINc). Among 228 lesions found in all patients, there were 148 HGINa and 80 HGINc. The independent relevant factors for HGINc were tobacco and alcohol usage, color, and gross type. To predict risk of HGINc, a three-factor model (TFM) was established with a highest area under curve (AUC) as 0.869 (95% CI, 0.852, 0.939). When the cut-off value was set as 0.3569184, the diagnostic accuracy, sensitivity, specificity, positive predictive value, and negative predictive value for HGINc was 81.14%, 88.75%, 77.03%, 67.62%, and 92.68%, respectively. HGINc differs greatly in endoscopic features from HGINa in our study. It's important to reduce misdiagnosis that our model was established with good predictive value for clinical application.

Immediate Breast Reconstruction in an 11-year-old Girl with a Large Malignant Phyllodes Tumor

Phyllodes tumors are rare fibroepithelial breast tumors representing less than 1% of all breast malignancies, with an extremely uncommon presence in the pediatric population.¹ Although prognosis is favorable following excision given their indolent course, they often grow rapidly and frequently recur. As such, they can present unique oncologic and reconstructive challenges. Herein we present a case of a malignant phyllodes tumor in an 11-year-old girl treated with total skin-sparing mastectomy and adjustable saline implant, and explore the reconstructive challenges of this unique case.

Study of clinicopathological factors and their impact on survival in phyllodes tumour of breast at tertiary care cancer centre in India

BACKGROUND

Phyllodes tumour is a rare breast neoplasm having three histological types i. e benign, borderline and malignant. Surgical excision is the mainstay of treatment, but quantification of adequate margin required during excision is still a matter of debate. Role of adjuvant radiotherapy also remains controversial.

AIMS

Study of prognostic factors in patients with phyllodes tumour of breast and their effect on survival.

SETTING AND DESIGN

A retrospective analysis.

MATERIAL AND METHODS

From the year 2016 to 2019 we included 54 patients in this study and assessment of clinical and histopathological features, requirement of adjuvant radiotherapy and their effect on DFS (disease free survival) and OS (overall survival) was done. Log-rank test was used for univariate analysis and multivariate analysis was done by using Cox propotion hazard ratio method.

STATISTICAL ANALYSIS

Descriptive statistics was used for calculating proportion and median value. Survival analysis was done by using Kaplan Meier method. P value of <0.05 was considered statistically significant.

RESULTS

Mitotic count and presence of heterologous component had significant effect on overall survival (OS) and disease free survival (DFS) on multivariate analysis. No effect of adjuvant radiotherapy and the type of surgery (breast conservation surgery v/s mastectomy) was found on survival (OS, DFS).

CONCLUSION

Surgery with adequate margins should be the treatment of choice for tumours with borderline and malignant histological type Histological features like high mitotic count and stromal overgrowth are known prognostic factors, however, heterologous component is also an important prognostic factor and should be studied in large randomized trials. Role of adjuvant radiotherapy remains controversial.

Correlations of morphological features and surgical management with clinical outcome in a multicentre study of 241 phyllodes tumours of the breast

AIMS

Phyllodes tumours (PTs) represent an unusual but complex group of breast lesions with a tendency to recur locally and, less commonly, metastasise. On core biopsies, their appearances can be difficult to discriminate from those of other fibroepithelial lesions, which may compromise their surgical management. The aims of this study were to assess the preoperative diagnosis of PTs and to evaluate the impacts of surgical management and morphological features on their behaviour.

METHODS AND RESULTS

We combined datasets from three centres over two decades, including core biopsies, excision specimens, and follow-up. Core biopsy results were compared with final excision specimens. The relationships of surgical procedure and morphological features with local recurrence (LR) and metastasis were assessed. Two hundred and forty-one PTs were studied. Core biopsy resulted in a diagnosis of possible or definite PT in 76% of cases. Malignant tumours were more likely to be larger, occurred at an older age, and were surgically more challenging, with difficulties being encountered in achieving negative margins. There were 12 cases (5%) that showed LR alone, and another six cases (2.5%) that had distant metastases. Morphological features associated with adverse outcome were grade of PT, increased mitotic counts, necrosis, infiltrative margins, stromal atypia, and heterologous components. Both LR and metastatic behaviour correlated with larger size and distance to margins.

CONCLUSIONS

Our results suggest that excision margins have a significant impact on LR of PT, whereas metastatic behaviour is influenced by tumour biology. We add to the evidence base on histological features of tumours that contribute to long-term outcomes of PT patients.