Immunohistochemical profile of cystosarcoma phyllodes of the breast: a study of 23 cases

The malignant degeneration of a phyllode tumour in man: A case report

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Through this case report and a review of the literature, we wish to highlight the difficulties of clinical and paraclinical diagnosis as well as the therapy.

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Malignant phyllodes tumour is a separate entity from breast cancer, it is rare, it is completely different from epithelial cancer and it can exist in man.

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The three pathological types (benign, borderline and malignant) were reported in men.

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Very few cases of phyllodes tumour were reported in men.

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Malignant phyllodes tumour of the breast show clinical and mammographic signs comparable to those of benign lesions.

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Its epidemiology is particular and it has particular difficulties in clinical and paraclinical diagnosis. The treatment is based on surgery, which may be a large lumpectomy or mastectomy, lymph node removal is unnecessary, and the prognosis depends on several factors, the most important of which are margins of surgical exeresis.

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Wide local excision is the standard of care for phyllodes tumours (with or without adjuvant radiotherapy in malignant lesions). The combination of adjuvant treatment with radiotherapy or chemotherapy is still under discussion.

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There is a risk of local relapse and distant metastases, in particular to the lung.

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The higher rate of distant metastases is found when the resection margins are less than 10 mm.

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After resection, the prognostic factors for phylloid sarcoma correspond to the histological grade, surgical margins and the presence of tumour necrosis. tumour size may also be a pejorative factor.

Introduction

Malignant phyllodes tumours of the breast represent less than 1% of all breast cancers.

Few cases of phyllodes tumours have been reported in men.

Case presentation

We present the case of a 60-year-old man who was operated on one year ago for a breast tumour that had undergone a lumpectomy with an anatomopathological study in favour of a grade 2 phylloid tumour. He was admitted to hospital with a palpable mass in his right breast. The lumpectomy enlarged to the right pectoralis major muscle was then performed with clear surgical margins.

Microscopic examination revealed high-grade malignant phyllodes.

Postoperatively, after 3 months, the patient was given a breast MRI and a PET/CT scan which returned without abnormalities.

The patient is followed for eight months and has shown no signs of recurrence.

Discussion

Malignant phyllodes tumours of the breast show clinical and mammographic signs comparable to those of benign lesions.

The diagnosis is confirmed by histology, treatment is based on surgery, which may be a large lumpectomy or mastectomy, and the prognosis depends on several factors, the most important of which is the margin for surgical resection.

Conclusion

The best treatment is a wide local excision with a safety margin of 1 cm, unless it is metastatic.

Early diagnosis and surgery improves the prognosis.

Morphologic and genetic heterogeneity in breast fibroepithelial lesions-a comprehensive mapping study

Breast fibroepithelial lesions (FELs) encompass the common fibroadenoma (FA) and relatively rare phyllodes tumour (PT); the latter entity is usually classified as benign, borderline or malignant. Intratumoural heterogeneity is frequently present in these tumours, making accurate histologic evaluation challenging. Despite their rarity, PTs are an important clinical problem due to their propensity for recurrence and, in the case of malignant PT, metastasis. Surgical excision is the mainstay of management. Recent work has uncovered myriad genetic alterations in breast FELs. In this study, exome sequencing was performed on seven cases of morphologically heterogeneous breast FELs, including FAs, PTs of all grades, and a case of metaplastic spindle cell carcinoma arising in PT, in order to elucidate their intratumoural genetic repertoire. Gene mutations identified encompassed cell signalling, tumour suppressor, DNA repair and cell cycle regulating pathways. Mutations common to multiple tumour regions generally showed higher variant allele frequency. Frequent mutations included MED12, TP53, RARA and PIK3CA. Histological observations of increased cellular density and pleomorphism correlated with mutational burden. Phylogenetic analyses revealed disparate pathways of possible tumour progression. In summary, histological heterogeneity correlated with genetic changes in breast FELs.

Immunohistochemical expression of Ki-67, p53, and CD10 in phyllodes tumor and their correlation with its histological grade

CONTEXT:

Phyllodes tumors (PTs) are the fibroepithelial neoplasms of the breast. Histologically, PTs are divided into three subgroups according to their clinicopathological behavior: benign, borderline, and malignant. It is at times difficult to ascertain the grade of PT on morphological criteria alone, especially borderline PT may be at times difficult to distinguish from its benign or malignant counterparts.

AIMS:

This study was undertaken to evaluate an immunohistochemical panel of Ki-67, p53, and CD10 in PT and to determine their expression in PT in correlation with its grade.

SETTINGS AND DESIGN:

This was a retrospective study.

SUBJECTS AND METHODS:

The study included six malignant, six borderline, and twelve benign PT. Expressions of Ki-67, p53, and CD10 were evaluated on all the 12 cases and compared in these three categories.

STATISTICAL ANALYSIS USED:

Chi-square test was applied, and P < 0.05 was taken as statistically significant.

RESULTS:

Stromal expression of Ki-67 and p53 between the benign and borderline/malignant group showed a statistically significant difference. Neither CD10 expression nor epithelial expressions of Ki-67 and p53 were found significant. Periepithelial accentuation of Ki-67 and p53 immunostaining was noted in all positive cases.

CONCLUSIONS:

Ki-67 labeling index and p53 immunostaining can be a useful adjunct to determine the grade in difficult cases. However, no single immunomarker can reliably distinguish between benign and borderline phyllodes in all cases.

Expression of biomarkers in the AKT pathway correlates with malignancy and recurrence in phyllodes tumours of the breast

AIMS

Phyllodes tumours (PTs) of the breast are uncommon fibroepithelial neoplasms with the potential to recur and metastasise. Apart from histological grading, the expression of biological markers and its relationship with tumour behaviour have been topics of interest. The phosphatidylinositol 3-kinase (PI3K)-AKT pathway regulates diverse biological functions, and is one of the most frequently deregulated pathways in cancers. Little is known of PI3K-AKT pathway alteration in PT. We aim to investigate the alterations in different component of AKT pathway in PTs.

METHODS AND RESULTS

This study investigated the expression of four biological markers involved in this pathway (PTEN, INPP4B, PI3KCA and pAKT) in 134 PTs by the use of immunohistochemistry. According to an immunoscore incorporating staining intensity and proportion, low epithelial INPP4B expression (P = 0.045) was associated with recurrence. A trend of association was found for low epithelial PTEN expression with recurrence (P = 0.090). Interestingly, low epithelial INPP4B expression was also associated recurred tumours (P = 0.043). Stromal PI3KCA expression (P = 0.016) and pAKT expression (P = 0.006) were found to be correlated with increased histological grade, but an opposite trend was seen for stromal INPP4B expression (P = 0.018). In addition, epithelial and stromal PTEN expression, PI3KCA expression and pAKT expression showed strong correlations with each other (P ≤ 0.001).

CONCLUSIONS

These findings indicate that alterations in AKT pathway activation may correlate with malignant transformation and recurrence in PT. Low epithelial INPP4B/PTEN expression is associated with shorter recurrence-free survival. These observations suggest that the pathway may play a crucial role in the biological behaviour and progression of PT, and assessing the expression of this pathway may be of value in diagnosis, grading, prognostication, and management.

A rare case of a giant ulcerated benign phyllode tumor

Phyllode tumors are rare fibroepithelial neoplasms divided into three histological grades according to their potential for malignancy. Low grade tumors are usually smaller with a slower evolution. We present here the case of a 40 year old women presenting an augmentation over one month of the volume of her right breast with an ulcerated mass measuring 25cm. The clinical characteristics were in favor as a malignant tumor. The radiological findings were not contributive and the pathologic examinations of the biopsies were benign. A therapeutic and diagnostic mastectomy was thus performed and the final pathologic examination confirmed a benign phyllode tumor. These rare tumors are very deceitful for the radiologic investigations are poorly contributive. Likewise, the pathologic examination can be incorrect. Biopsies must be repeated and a mastectomy performed if any doubts remain.

Functional Relationship and Gene Ontology Classification of Breast Cancer Biomarkers

Breast cancer is a complex disease that still imposes a significant healthcare burden on women worldwide. The etiology of breast cancer is not known but significant advances have been made in the area of early detection and treatment. The advent of advanced molecular biology techniques, mapping of the human genome and availability of high throughput genomic and proteomic strategies opens up new opportunities and will potentially lead to the discovery of novel biomarkers for early detection and prognostication of breast cancer. Currently, many biomarkers, particularly the hormonal and epidermal growth factor receptors, are being utilized for breast cancer prognosis. Unfortunately, none of the biomarkers in use have sufficient diagnostic, prognostic and/or predictive power across all categories and stages of breast cancer. It is recognized that more useful information can be generated if tumors are interrogated with multiple markers. But choosing the right combination of biomarkers is challenging, because 1) multiple pathways are involved, 2) up to 62 genes and their protein products are potentially involved in breast cancer-related mechanisms and 3) the more markers evaluated, the more the time and cost involved. This review summarizes the current literature on selected biomarkers for breast cancer, discusses the functional relationships, and groups the selected genes based on a Gene Ontology™ classification.

A Diagnostic Approach to Fibroepithelial Breast Lesions

Fibroepithelial breast lesions encompass a heterogeneous group of neoplasms that range from benign to malignant, each exhibiting differing degrees of stromal proliferation in relation to the epithelial compartment. Fibroadenomas are common benign neoplasms that may be treated conservatively. Phyllodes tumors are relatively rare lesions, and classified as benign, borderline, or malignant based on histologic evaluation of various parameters. The diagnostic interpretation of "gray-zone" fibroepithelial lesions often imposes formidable demands on a pathologist's skills. This article offers practical recommendations for the diagnostic workup of these lesions, including the appropriate utilization of ancillary investigations and the approach to core needle biopsies.

Phyllodes tumors of the breast in 2 sisters: Case report and review of literature

RATIONALE

Phyllodes tumors (PT) of the breast are rare neoplasm originating from fibroepithelial component. To our knowledge, our report is the first reported case of PT in 2 sisters.

PATIENT CONCERNS

We presented 2 cases of PT of the breast involving in 2 sisters. On physical examination of the younger sister, a firm mass measuring approximately 3 cm in diameter was identified in upper inner quadrant of the right breast. Physical examination of the elder sister revealed a 3 cm lump in upper outer quadrant of the left breast.

DIAGNOSES

Histopathology of the younger sister revealed a malignant PT. The elder sister was diagnosed with borderline PT.

INTERVENTIONS

The younger sister with malignant PT underwent right mastectomy. The elder sister with borderline PT was scheduled for wide resection of the mass in the left breast.

OUTCOMES

After a follow-up of 23 months, no local or distant recurrence was observed.

LESSONS

Our cases indicate that genetic factor may contribute to the risk of PT of the breast. Markers such as p53 and Ki-67 may have some correlation with PT malignancy.

A rare presentation of malignant phyllodes tumor with bloody nipple discharge-report of a case

Phyllodes tumor of the breast is a rare neoplasm, particularly in young women. It is usually presented as a unilateral palpable mass and nipple discharge presented as a symptom is rare. We reported a 22-year-old Taiwanese woman in our hospital for right breast tumor with nipple discharge. Preoperative diagnosis was intraductal papilloma but the histological examination showed a malignant phyllodes tumor with intraductal growth. Symptom of nipple discharge and intraductal growth in phyllodes tumor are rare presentations. Therefore, the management and the biological behavior of this uncommon tumor are discussed in this patient.

Expression of CAF-Related Proteins Is Associated with Histologic Grade of Breast Phyllodes Tumor

Purpose. The purpose of this study was to investigate the expression of cancer-associated fibroblast- (CAF-) related proteins and the implications in breast phyllodes tumor (PT). Methods. Tissue microarrays of 194 PT cases (151 benign PT, 27 borderline PT, and 16 malignant PT) were constructed. We performed immunohistochemical staining for CAF-related proteins (podoplanin, prolyl 4-hydroxylase, FAPα, S100A4, PDGFR α/β, and NG2) and analyzed the results according to clinicopathologic parameters. Results. Expression of PDGFRα and PDGFRβ in the stromal component increased with increasing histologic grade of PT (p = 0.003 and p = 0.034, resp.). Among clinicopathologic parameters, only expression of FAPα in stroma was associated with distant metastasis (p = 0.002). In univariate analysis, stromal expression of PDGFRα was associated with shorter overall survival (p = 0.002). In Cox multivariate analysis, stromal overgrowth and PDGFRα stromal positivity were associated with shorter overall survival (p = 0.006 and p = 0.050, resp.). Furthermore, expression of PDGFRβ in stroma was associated with shorter overall survival in patients with malignant PT (p = 0.041). Conclusion. Stromal expression of PDGFRα and PDGFRβ increased with increasing histologic grade of PT. In addition, PDGFR stromal positivity was associated with shorter overall survival. These results suggest that CAFs are associated with breast PT progression.

Phyllodes tumours of the breast: a consensus review

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.

Rapidly progressive multifocal phyllodes tumour of the breast: A case report and review of the literature

INTRODUCTION

Malignant transformation of a phyllodes tumour is a rare form of breast cancer, accounting for just 0.5% of all breast cancer cases.(1) PRESENTATION OF CASE: We report a case of a 49 year old female with rapidly progressive, multifocal disease. She initially presented with two giant fibroadenomas which were excised. She represented eight months post surgery with two new lesions in the same breast, one suspicious, one suggestive of fibroadenoma. Biopsy was borderline. Surgery was therefore scheduled for wide local excision. At localisation two weeks later, at least eight lesions were seen on ultrasound scan. Three were removed as histology was at this point unknown to conserve the breast. Histology revealed intermediate grade DCIS, benign Phyllodes and borderline/malignant phyllodes. She was scheduled for mastectomy and immediate Strattice reconstruction. An MRI was performed pre-operatively to ascertain extent of disease. Two weeks post localisation, 13 lesions were identified. The right breast was entirely unaffected. Surgery interval was three weeks and final histology revealed 18 lesions, ranging from fibroadenoma through to borderline/malignant phyllodes with an incidental papilloma.

DISCUSSION

This is the first report of such rapid progression of disease, with 16 new lesions, of varied histology, developing in just an eight week period.

CONCLUSION

This case highlights the difficulty of forming a clear diagnostic and therapeutic pathway in this highly variable disease. Arguments for over and under treating these patients remain but those with any borderline/malignant potential have to be removed as recurrence is both common and aggressive, with a clear surgical margin the only proven protective factor.

CD34, CD117, and Ki-67 Expression in Phyllodes Tumor of the Breast: An Immunohistochemical Study of 33 Cases

Phyllodes tumors (PTs) of the breast are biphasic lesions, comprising an epithelial component set within a neoplastic spindle-celled stroma. These tumors have been classified as benign, borderline, and malignant based on a combination of histological criteria, including stromal cellularity, nuclear pleomorphism, mitotic rate, stromal overgrowth, and margin appearance. The aim of this study was to evaluate the expression of CD34, CD117 (c-kit), and Ki-67 in PT of the breast and attempt to correlate the staining pattern with tumor grade by morphology. Immunohistochemical expression of CD117, CD34, and Ki-67 was studied on formalin-fixed, paraffin-embedded archival tissue material from 33 cases of PT. Histologically, there were 21 benign, 6 borderline, and 6 malignant (high-grade) tumors. All 6 histologically malignant PTs were positive for CD117 (100%), but only 1 marked with CD34 (16.7%). Borderline PTs frequently coexpressed CD34 and CD117 (66.7%). The benign PTs, on the other hand, most commonly (52.4%) showed a CD34(+)/CD117(-) immunoprofile with 33.3% cases coexpressing the markers: that is, CD34(+)/CD117(+). Although most benign PTs (80.6%) showed a Ki-67 of <2%, a few cases showed slightly higher proliferation indices. This study indicates that CD34 and CD117 are differentially expressed in benign and malignant PTs. These markers, therefore, in combination, may be used as an adjunct to morphology in the subclassification of PTs.

Malignant phyllodes tumor in an 11-year-old premenarchal girl

Phyllodes tumor is uncommon in children, and the malignant form is rare. There have only been a few cases of benign phyllodes tumor reported in peripubertal children and only one malignant case. We report the second case of malignant phyllodes tumor in a premenarchal 11-year-old girl.

Evidence for transformation of fibroadenoma of the breast to malignant phyllodes tumor

Fibroadenoma (FA) and phyllodes tumor (PT) of the breast are biphasic tumors composed of variable proportions of epithelial and stromal cells. We identified a case of synchronous FA and PT in the same breast mass. Using laser capture microdissection, loss of heterozygosity analysis was performed on these components to gain potential insight into the histogenetic relationship between FA and PT. Genomic DNA was analyzed at 10 microsatellite loci by polymerase chain reaction. Both tumors showed allelic loss at D7S522. In addition, phylloid tumor showed allelic loss at TP53 and D22S264, not observed in FA. Our data suggest that FA and PT are clonally related and allelic loss at TP53 and D22S264 may be implicated in the progression of FA to phyllode tumor.

Phylloides tumor of the breast: a rare neoplasm, though not that innocent

Background

Cystosarcoma phylloides (CP) is an extremely rare form of breast cancer with an unpredictable clinical course. The histological characteristics of this neoplasm have not proved to offer much in the estimation of prognosis of these patients.

Patients and methods

In our clinics, in a time period of 38 years, 22 patients with cystosarcoma phylloides were treated. There were 5 cases of malignancy, 15 cases with benign tumors, and two cases histologically characterized as borderline neoplasia. Metastases were manifested in one patient. All patients were on a 5-year follow-up, except in five cases, one operated three years ago and four operated within the last two years.

Results

16 of 22 patients did not present any signs of local recurrence or metastases. There were three patients that manifested local recurrence and underwent supplementary ongectomy or mastectomy and are free of recurrence ever since. One patient with metastatic CP died.

Conclusion

Independently of its histopathological behavior, CP is a tumor difficult to be treated. Meticulous follow-up is mandatory in order to manage possible recurrence of the neoplasm.

Phyllodes tumor of the breast in an adolescent girl

Phyllodes tumor (PT) is an uncommon tumor in adolescent girls and young women. A case of PT in a 14-year-old girl is reported. The clinical examination showed a painless tumor that had grown during 10 months. Total excision of the mass with wide margin was performed. The diagnosis, behavior, and treatment of this rare tumor are discussed.

Phyllodes tumor: a clinicopathologic and immunohistochemical study of 30 cases

CONTEXT

Phyllodes tumors (PTs) of the breast are biphasic neoplasms composed of epithelium and a spindle-cell stroma. Currently, PTs are classified as benign, borderline, or malignant based on histopathologic features. However, histologic classification does not always predict outcome. Objective.-To determine the prognostic value of a variety of clinicopathologic features and immunoreactivities in PTs.

DESIGN

Sixteen benign, 8 borderline, and 6 malignant PTs with follow-up were examined for reactivity across a panel of immunohistochemical stains, including c-Kit, endothelin 1, p16, p21, p53, and Ki-67. Clinicopathologic features, including stromal cellularity, mitotic rate, and margin status, were also assessed. Tumor variables were compared among tumor subgroups and between tumors that did and did not recur.

RESULTS

Of the 30 PTs, 4 recurred (1 benign, 2 borderline, 1 malignant). One patient with a malignant tumor died of metastatic disease 34 months after initial diagnosis. The overall positive rate of c-Kit immunoreactivity was 13% in benign, 63% in borderline, and 67% in malignant PTs. Endothelin 1 epithelial cytoplasmic staining was seen in 100% of benign, 50% of borderline, and 17% of malignant PTs. Additionally, p16, p21, p53, and Ki-67 were differentially expressed among benign, borderline, and malignant tumors. Positive surgical resection margins was the only variable that significantly predicted recurrent disease (P = .02).

CONCLUSIONS

Stromal c-Kit positivity and epithelial endothelin 1 negativity are more often associated with malignant PTs; however, only positive margin status is significantly associated with tumor behavior.

Correlation of p53 and MIB-1 expression with both the systemic recurrence and survival in cases of phyllodes tumors of the breast

Phyllodes tumors are rare primary tumors of the breast. The study aimed at evaluating the immunohistochemical features of phyllodes tumors of the breast that may be useful for predicting the clinical outcome. We examined the immunohistochemical expression of the epidermal growth factor receptor (EGFR), HER2/neu, CD117/c-kit, p53, and MIB-1, and analyzed correlations between the immunohistochemical findings and the clinical outcome. The study included 41 patients with phyllodes tumor (20 benign, 5 borderline, and 16 malignant). Systemic recurrence occurred in 9 patients. The 2-year survival rate was 84%, and the 2-year recurrence-free survival rate was 77%. Six patients developed systemic recurrence within the first year after surgery. None of the phyllodes tumors was positive for HER2/neu or CD117/c-kit. Positive staining for p53 was seen in 10 phyllodes tumors (24%), and the median MIB-1 index was 10%. Both p53 expression and the MIB-1 index, but not the expression status of EGFR, were significantly correlated with the recurrence-free and overall survival. p53 expression status and MIB-1 index may be significant prognostic factors in patients with phyllodes tumors, and careful postoperative follow-up may be important in those cases showing positive expression of p53 and/or MIB-1 index.

Optimising preoperative diagnosis in phyllodes tumour of the breast

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.

p53 and c-kit (CD117) protein expression as prognostic indicators in breast phyllodes tumors: a tissue microarray study

Breast phyllodes tumors are fibroepithelial neoplasms whose clinical behavior is difficult to predict on histology. There is relatively scant data on the role of biological markers. In this study, we determined if p53 and CD117 (c-kit) protein expression was predictive of behavior in a series of 335 phyllodes tumors diagnosed at the Singapore General Hospital, using immunohistochemistry on tissue microarrays. Representative areas from 250 (75%) benign, 54 (16%) borderline and 31 (9%) malignant phyllodes tumors were selected for construction of tissue microarrays using the 2 mm punch. Immunohistochemistry for p53 and CD117 was carried out using the streptavidin-biotin method. Staining proportion and intensity of both epithelial and stromal elements were analyzed. p53 immunostaining was observed in the epithelium of 28 (10%) of 278 microarrays; myoepithelium of 53 (21%) of 251 microarrays; and stromal cells in 105 (36%) of 289 microarrays. CD117 immunohistochemical reactivity was noted in epithelial and stromal components of 175 (of 267, 66%) and 17 (of 273, 6%) microarrays, respectively. Stromal p53 and CD117 protein expression was associated with tumor grade (P < 0.05). Of 43 (13%) women who suffered recurrences during the follow-up period, CD117 stromal staining predicted recurrent disease (P<0.05), but p53 was not correlative. We conclude that tissue microarrays are a convenient method for evaluating immunostaining results of large numbers of phyllodes tumors. Although positive p53 stromal immunohistochemical detection may corroborate histologic malignancy, it is CD117 protein expression in phyllodes tumor stromal cells that may be of potential utility in predicting recurrent disease.

Scintimammographic Findings of Phyllodes Tumor of the Breast in a Double-phase Study with Tc-99m (V)DMSA and Tc-99m MIBI: a Case Report

We present a case of phyllodes tumor of the breast in a 78-year-old woman evaluated with Tc-99m (V)DMSA and Tc-99m MIBI scintimammography, acquired in separate sessions (10 and 60 min post-injection). Tc-99m (V)DMSA was accumulated intensely within the mass [tumor to background ratio (T/B) >3], whereas Tc-99m MIBI had significantly lower uptake (T/B 1.9). Histology revealed a phyllodes tumor (maximum diameter 15 cm) and approximately three mitoses over 10 fields of view (FOV) x40, foci of epithelial hyperplasia and apocrine metaplasia. Stromal Ki-67 expression was 7%. The tumor was considered to be benign and the patient underwent mastectomy. One year later the patient presented with local malignant recurrence of the disease with over 15 mitoses per 10 FOV. Tc-99m (V)DMSA seems to have an advantage over Tc-99m MIBI in detecting mesenchymal tumors with unforeseen biological behavior and Ki-67 over-expression, such as phyllodes tumors, even with primary negative histological findings.

Prise en charge des tumeurs phyllodes du sein à l'Institut national d'oncologie de Rabat, Maroc

OBJECTIVES

Phyllodes tumors of the breast (PTB) are rare fibro epithelial tumors. Their terminology, histological classification and their treatment are exposed to controversy. The aim of our work is to underline the epidemiological, clinical, histological, therapeutical, prognostic and evolutive features of these tumours through a retrospective study and a review of the literature.

PATIENTS AND METHODS

We reviewed at the National Institute of Oncology of Rabat, Morocco, between 1985 and 1998, all the files of patients with histological certainty of PTB, doubtful PTB were excluded. We collected epidemiological, clinical, histological, therapeutical, prognostic and evolutive features of these tumours.

STATISTICS

quantitative parameters were represented by mean +/- S.D. and qualitative parameters by percentage or effective.

RESULTS

We studied nine cases of PTB, which represented 0.09% of all primitive tumors of the breast treated at our institution during the study period. All our patients were female. Mean age was 37.3 +/- 10.07 years. Two of our patients (22.2%) had a history of fibroadenoma and 44.4% were nulliparous. Mean delay before consulting was 60.7 +/- 17.56 months and the median tumour size was 13 +/- 7.47 cm. Pathological findings were six benign or borderline phyllodes tumours (66.7%) and three cystosarcomas phyllodes (33.3%). The treatment consisted in simple mastectomy in seven cases (77.8%) and tumorectomy in two cases (22.2%). All the surgical margins were clear. Two of the three cystosarcomas phyllodes received adjuvant external bean radiation therapy 50 Gy on the thoracic chest wall. After a median outcome of 3 +/- 2 years ranging from 3 to 74 months, we did not note any relapse or metastasis.

DISCUSSION AND CONCLUSION

In our series, PTB happened exclusively in females. History of fibroadenoma within 22.2% of the patients suggests the hypothesis of a filiation between these two entities. Their distinctive features were young age in diagnosis, long delay before consulting, important tumor size, predominant benign and borderline histological types, treatment mainly surgical and good local and distant control.