Expression of class III beta-tubulin in neuroendocrine tumours of gastrointestinal tract

Class III b-tubulin is presented as a specific marker for the cells of neuronal origin as well as for the tumours originating from these cells. Its expression is considered one of the earliest events that appear in the cells revealing neuronal differentiation. Using monoclonal antibody TU-20 in an immunohistochemical analysis, we studied the expression of class III b-tubulin in gastrointestinal carcinoid tumours. Paraffin-embedded, formalin-fixed tissue sections from 49 tumour samples obtained from following locations: stomach (4 cases), small intestine (8 cases), appendix (18 cases), rectum (3 cases), pancreas (5 cases), liver metastases (7 cases) and lymph node metastases (4 cases) were used in the study. In 41 of the 49 tumour samples (83.7%), positive staining for class III b-tubulin was detected, while 8 tumour samples (16.3%) were negative. Expression of class III b-tubulin was prominent in all three rectal carcinoids and in three atypical carcinoids located in small intestine. Pancreatic neuroendocrine tumours revealed either weak immunostaining (2 cases), or were negative for this marker (3 cases). The intensity of class III b-tubulin immunolabelling was not related to the degree of tumour differentiation. The results of this study suggest that class III b-tubulin could be a perspective marker for gastrointestinal neuroendocrine tumours. Moreover, the differences in its expression could also elucidate some aspects of histogenetic relationships of neuroendocrine tumours of gastrointestinal tract.     

Increased expression of matrix metalloproteinase-2 (MMP-2) predicts tumour recurrence and unfavourable outcome in non-small cell lung cancer

The purpose of this study was to analyse the expression of matrix metalloproteinase-2 (MMP-2) and its extracellular matrix metalloproteinase inducer (EMMPRIN) in non-small cell lung cancer (NSCLC), and to evaluate their significance to predict tumour behaviour. The study consists of 212 patients treated by the resection of the tumour. Tumour samples were stained immunohistochemically, and the expression of MMP-2 and EMMPRIN was evaluated both in tumour cells and in peritumoural stromal tissue. The results were compared with clinicopathological factors and survival of the patients. High expression of MMP-2 in tumour cells was found in 83 out of 191 cases (44%). Adenocarcinomas showed more often high expression of MMP-2 as compared with squamous cell or large cell carcinomas (p=0.001). High cancer cell associated MMP-2 expression was associated with increased tumour recurrence (p=0.001). Tumour stroma showed positive staining in 162 (98%) cases and was considered highly stained in 120 (72%) cases. The high stromal MMP-2 expression was noticed more often among large cell carcinomas as compared with other histological types (p=0.007). High cancer cell associated EMMPRIN expression was found in 115 (61%) cases and was associated only with high MMP-2 expression in tumour cells (p=0.006). In overall survival (OS) and disease free survival (DFS) analyses, type of tumour (p=0.001 and p=0.0004), advanced stage (p=0.001 and p=0.013) and high MMP-2 expression in tumour cells (p=0.018 and p=0.001) were associated with poor survival. Also, high stromal MMP-2 expression was related to poor outcome in both OS and DFS analyses (p=0.010 and 0.045, respectively). In multivariate analysis, stromal MMP-2 expression retained its prognostic value to predict OS and DFS (p=0.028 and p=0.039, respectively), together with tumour type and stage (p=0.017, p=0.001 and p=0.021, p=0.008, respectively). The present study shows the significant prognostic value of MMP-2 in NSCLC suggesting that the use of MMP-2 is valuable in determining the patients with more aggressive disease.     

Stereotactic biopsy and cytological diagnosis of solid and cystic intracranial lesions

Cytological smears from 115 consecutive cases of stereotactic biopsies of intracranial lesions were reviewed. Ninety-five lesions were solid and 20 cystic. Material from 90 solid and 13 cystic lesions was sent both for cytological and histological examination. In 66 of the solid lesions, the cytological diagnosis was confirmed by histology (five were benign lesions and 61 malignant tumours: 56 primary brain tumours, three metastases and two lymphomas). In 24 cases with discrepant cytology and histology, the histology was inconclusive or insufficient in 14 cases, while cytology established the diagnosis of astrocytoma grade II (seven cases), metastases (two cases), gliosis (one case) and benign (four cases). Necrosis of tumour type was observed cytologically in six patients representing glioblastoma (two cases), anaplastic astrocytoma (one case), lymphoma (one case) and normal brain (two cases) histologically. Three cases reported cytologically as benign were primary brain tumour (two cases) and gliosis (one case). One smear of a glioblastoma was insufficient for cytological diagnosis. Cystic lesions were cytologically benign in 17 cases and malignant in three cases. Histology from the cyst wall confirmed the malignant diagnosis in three cases and showed tumour in six more cases, a benign process (two cases), changes induced by radiotherapy for arteriovenous malformation (one case) and insufficient material (one case). In conclusion, cytology from solid brain lesion allows an accurate diagnosis and subtyping of tumours in a majority of cases, and can thus be used to choose type of therapy. In cystic brain tumours, however, examination of the cystic fluid, is often inconclusive and a biopsy from the cyst wall should be performed if there is clinical or radiological suspicion of tumour.     

Role of fine needle aspiration cytology in diagnosis of pleomorphic adenomas

Role of fine needle aspiration cytology in diagnosis of pleomorphic adenomas This retrospective study was carried out to review the cases diagnosed as pleomorphic adenoma in major or minor salivary glands and determine the difficulties encountered on typing this tumour on fine needle aspiration cytology (FNAC). Over a 19‐year period (1982–2000) 488 pleomorphic adenomas were diagnosed on FNAC from different sites (parotid – 372 cases, submandibular – 95 cases; oral cavity – 21 cases). Histology was available in 232 cases. Twenty‐nine cases where a histological diagnosis of pleomorphic adenoma was made but the cytological diagnosis was variable were also reviewed. In 216 of the 232 cases a good cytohistological correlation was available. On review only 4 of the 16 cases initially diagnosed as pleomorphic adenoma on FNAC where the histology revealed a different tumour were categorized as pleomorphic adenoma, while 3 each were classified as adenoid cystic carcinoma and benign tumour ?type, and 2 each were diagnosed to be muco‐epidermoid carcinoma, monomorphic adenoma and acinic cell carcinoma. On review of the FNAC smears from 29 cases where a histological diagnosis of pleomorphic adenoma was available while the cytological diagnosis was variable, only 11 (38%) were categorized as pleomorphic adenoma. In the majority of the remaining cases the cytological diagnosis did not alter markedly, 7 of 10 cases where the tumour could not be typed on cytology initially could not be typed even on review. In conclusion, FNAC is an ideal, fairly accurate preoperative procedure for the diagnosis of pleomorphic adenomas. Certain diagnostic problems occur in differentiating pleomorphic adenomas from adenoid cystic carcinoma, monomorphic adenoma and mucoepidermoid carcinoma. Carcinoma ex‐pleomorphic adenoma is difficult to identify on FNAC and in our series all 4 such cases on histology were considered benign on cytology.     

Serotonin-producing pancreatic endocrine tumour. Histological, ultrastructural and immunohistochemical study of a case

Serotonin-producing pancreatic endocrine tumours are rare neoplasms which in most cases exhibit malignant biological behaviour. These tumours, in the majority of the well-documented cases, are composed of argyrophil- and argentaffin-positive cells which contain large pleomorphic neurosecretory granules. In contrast, argyrophilic non-argentaffin pancreatic endocrine tumours with tumour cells containing round neurosecretory granules are exceptional. In this study we describe such a tumour not associated with clinical evidence of carcinoid syndrome in a 60-year-old woman. Histological examination revealed tumour extension in pancreatic lymphatic vessels and veins but no evidence of locoregional or distant metastases. Ten months after surgery the patient showed no recurrence of the disease. Immunohistochemistry revealed cytoplasmic serotonin production in the tumour cells which were negative for anti-gastrin, insulin, glucagon, somatostatin, pancreatic polypeptide (PP), vasoactive intestinal peptide (VIP) and ACTH. This study emphasizes the usefulness of combined ultrastructural and immunohistochemical investigations in order to identify and characterize the rare pancreatic endocrine tumours with serotonin production.     

Dual tumours in the GI tract: synchronous and metachronous stromal (GIST) and epithelial/neuroendocrine neoplasms

Gastrointestinal stromal tumours (GIST) constitute the most frequent group of mesenchymal tumours in the gastrointestinal tract (GI). During the last several decades major advances have been taken in the diagnostics, treatment, and understanding of its pathogenesis. However, much less is known about the either metachronous or synchronous concurrence of GIST and other tumours of different histogenesis. In the present study clinicopathological data of 43 patients with histologically proved gastrointestinal stromal tumour were studied mainly in regard of the occurrence of a secondary neoplasm. Among the 43, 7 cases were found with secondary tumour mainly of epithelial origin. In three cases (cases 3, 5, and 7) GIST concurred with colorectal adenocarcinoma, in one case (case 1) GIST occurred in a patient with a 3-years-history of chronic lymphocytic leukaemia (CLL), in other two (cases 2 and 4) the stromal tumour was combined with in situ adenocarcinoma of the stomach and carcinoid of the pancreas, respectively. In case 6, GIST concurred with a duodenal Brunner gland adenoma. In five cases the stromal tumour and the other neoplasm occurred synchronously, and in four of them, being the stromal tumour clinically silent, GISTs were intraoperative findings. This confirms the importance of surgical intraabdominal control before closure. In one hand the repeated concurrence of GIST and colorectal adenocarcinoma in our series, and on the other hand, that of GIST and adenocarcinoma of the stomach in the literature, may indicate an at least partly common factor, which may be involved in the pathogenesis of these neoplasms.     

Tumour-stromal interactions in acid-mediated invasion: A mathematical model

It is well established that the tumour microenvironment can both promote and suppress tumour growth and invasion, however, most mathematical models of invasion view the normal tissue as inhibiting tumour progression via immune modulation or spatial constraint. In particular, the production of acid by tumour cells and the subsequent creation of a low extracellular pH environment has been explored in several ‘acid-mediated tumour invasion’ models where the acidic environment facilitates normal cell death and permits tumour invasion. In this paper, we extend the acid-invasion model developed by Gatenby and Gawlinski (1996) to include both the competitive and cooperative interactions between tumour and normal cells, by incorporating the influence of extracellular matrix and protease production at the tumour-stroma interface. Our model predicts an optimal level of tumour acidity which produces both cell death and matrix degradation. Additionally, very aggressive tumours prevent protease production and matrix degradation by excessive normal cell destruction, leading to an acellular (but matrix filled) gap between the tumour and normal tissue, a feature seen in encapsulated tumours. These results sugest, counterintuitively, that increasing tumour acidity may, in some cases, prevent tumour invasion.     

Phospho-Akt Immunoreactivity in Prostate Cancer: Relationship to Disease Severity and Outcome,Ki67 and Phosphorylated EGFR Expression

Background

In the present study, we have investigated the prognostic usefulness of phosphorylated Akt immunoreactivity (pAkt-IR) in prostate cancer using a well-characterised tissue microarray from men who had undergone transurethral resection due to lower urinary tract symptoms.

Methodology/Principal Findings

pAkt-IR in prostate epithelial and tumour cells was assessed using a monoclonal anti-pAkt (Ser⁴⁷³) antibody. Immunoreactive intensity was determined for 282 (tumour) and 240 (non-mlignant tissue) cases. Tumour pAkt-IR scores correlated with Gleason score, tumour Ki67-IR (a marker of cell proliferation) and tumour phosphorylated epidermal growth factor receptor (pEGFR)-IR. For cases followed with expectancy, a high tumour pAkt-IR was associated with a poor disease-specific survival, and the prognostic information provided by this biomarker was additive to that provided by either (but not both) tumour pEFGR-IR or Ki67-IR. Upon division of the cases with respect to their Gleason scores, the prognostic value of pAkt-IR was seen for patients with Gleason score 8–10, but not for patients with Gleason score 6–7.

Conclusions/Significance

Tumour pAkt-IR is associated with both disease severity and disease-specific survival. However, its clinical use as a biomarker is limited, since it does not provide prognostic information in patients with Gleason scores 6–7.     

High levels of sFas and PBMC apoptosis before and after excision of malignant melanoma--case report

In our study we investigated the level of apoptosis in PBMCs and the serological level of sFas (CD95/APO-1) in 22 patients with malignant melanoma (12 patients with unique cutaneous primary tumour and 10 patients with unique brain metastasis). The first determination was performed before tumour excision and the second at 6-7 months after excision. Results in patients with primary tumour in the first determination: 6 patients with over normal values in PBMCs apoptosis and 5 patients with increased values of sFas. In the second determination: apoptosis was increased in 5 patients and sFas level was increased in 4 cases. In patients with metastases in the first determination apoptosis of PBMC was increased in 7 cases and sFas in 5 cases. In the second determination apoptosis was increased in 4 cases and sFas was increased in 4 cases. Our results show that half of the investigated patients presented elevated values of PBMCs apoptosis and Fas receptor both before and 6-7 months after tumour excision. Apoptosis values for PBMCs and sFas values were with 1/4 higher than normals. There was no difference in clinical evolution of the patients with normal or increased values for studied parameters. Clinical evolution was performed for 1 year. The presence of increased values for PBMCs and sFas after tumour excision, primary or metastasis is surprising and hard to explain. It is possible that tumoral evolution induces a disregulation at PBMCs level or other cells level that persists unexpectedly, after tumour excision or apoptotic processes, in a certain level to be independent and anterior to tumour development.     

Transcription factor snail1 expression and poor survival in pharyngeal squamous cell carcinoma

Snail1, a key regulator of epithelial-mesenchymal transition (EMT), plays an important role in tumour progression. Previous studies of snail1 have mainly focused on the epithelial tumour cells. The objective of this study was to evaluate the expression of snail1 protein in endothelial cells, stromal myofibroblasts and malignant epithelial cells of pharyngeal squamous cell carcinomas (PSCC), as well as its relation to clinicopathological features and survival. One hundred and ten tissue microarray samples were analyzed for snail1 expression using immunohistochemistry. In endothelial cells snail1 expression was observed in 51 (48%) of 107 cases and it predicted reduced disease specific survival (DSS) (p=0.009). In 49 (46%) tumour samples snail1 immunostaining was detected in stromal myofibroblasts and there was a tendency to poorer DSS in that group (p=0.067). Snail1 expression in endothelial cells and stromal myofibroblasts is also associated with hypopharyngeal tumours (p=0.01 and p=0.038 respectively), increasing T category (T3-4) (p=0.005, p=0.037 respectively) and poorer general condition of the patient (Karnofsky performance status score <70; p=0.029, p=0.039 respectively). Moreover endothelial expression correlated with advanced stage (III-IV) (p=0.005) and poorer differentiation (grade 2-3; p=0.012). In malignant epithelial cells snail1 immunostaining was detected in 75 of 110 cases (68%). Expression of the protein was more common in hypopharyngeal tumours (p=0.044). Snail1 positive tumours associated with a lower Karnofsky performance status score (p=0.039) and regional failure (p=0.042). Our findings indicate that snail1 protein expression in endothelial cells and to some extent also in tumour stromal myofibroblasts seems to be a predictor of poor survival in PSCC. The presence of snail1 protein in tumour microenvironment rather than in malignant epithelial tumour cells may induce tissue remodelling and tumour progression.     

The role of repeated transurethral resection in the treatment of bladder tumor

Complete removal of the tumour or deep invasion can be proven by repeated transurethral resection of bladder wall at the previous tumour site. Six weeks after transurethral resection of bladder tumour (TURB), in all but TaG1 cases repeated resection were performed for the evaluation of radicality in 62 patients, 43 males and 19 females, suffering bladder cancer, from October 1998. In the case of positive histology another resection was performed for security reason. In the case of 38 superficial (Tis, Ta, T1) cancers, repeated resection revealed negative, identical or different T stage compared with previous histology in 28, 5 and 5 cases, respectively. In 7 cases repeated resection was applied as second intervention after the incomplete resection of large tumour mass. Indication of repeated resection was insufficient depth of resection and carcinoma in situ in 13 and 4 cases, respectively. Based on our data, we conclude that repeated resection should be performed when tumour-free status is not justified and biopsy according to Bressel was not taken.     

Chromosome 17 abnormalities and lack of TP53 mutations in paediatric central nervous system tumours

Central nervous system (CNS) tumours are the most common solid tumours in children. Cytogenetic and molecular genetic studies of these neoplasms have previously shown abnormalities of chromosome 17, implicating genes on this autosome in tumorigenesis. To identify mutations in the TP53 tumour suppressor gene (17p13.1), we have sequenced the five highly conserved regions of this gene in 29 mixed paediatric CNS tumors. No mutations were detected by this analysis. In order to identify other candidate disease loci on chromosome 17, we have carried out a detailed deletion mapping analysis using 16 polymorphic DNA markers on 19 of the above tumours and an additional four cases. Abnormalities of chromosome 17 occurred in nine cases (39%), six of which were primitive neuroectodermal tumour (PNET)-medulloblastomas. These findings suggest that it is unlikely that the TP53 gene is directly involved in the development of common paediatric brain tumours. This is in contrast to findings from adult brain and other tumour types. Moreover, the frequency of chromosome 17 aberrations, especially in PNET-medulloblastomas, suggests that other genes on this chromosome contribute to tumourigenesis.     

Malignant lymphoma of follicle centre cells with marked nuclear lobation

Four cases of malignant B-cell lymphoma characterized by a conspicuous component of tumour cells with markedly lobatated nuclei are described. Two exhibited a follicular and two a diffuse growth pattern. The tumour cell population formed a continuous spectrum comprising both cells resembling normal follicle centre cells and multilobated lymphoma cells. Cytomorphological analysis of the multilobated cell group indicated a differentiation series from centroblast-like cells with moderately lobated nuclei to large and medium-sized cells with marked nuclear lobation which revealed features of centrocytes. In three cases (1, 3, and 4) the majority of these multilobated cells showed plasmacytoid differentiation in their cytoplasm in conjunction with the synthesis of monotypical cytoplasmic immunoglobulin. No plasmacytoid features were present in a fourth case (2). In only one case (4) monotypical surface immunoglobulin was detectable on the tumour cells. A close relationship between the multilobated tumour cells and follicle centre cells was further substantiated by the finding of a similar cell variant in the follicle centres of a control group of non-neoplastic lymph nodes. It included cells with plasmacytoid differentiation which synthesized polytypical immunoglobulin. We consider this type of B-cell lymphoma with a conspicuous component of cells with lobated nuclei as a variant of malignant lymphoma, centroblastic/centrocytic.     

Lymphoepithelioma – a tumour rarely observed in children (3 cases)

Lymphoepithelioma rarely develops in children. In its early stage it may manifest itself only as enlarged cervical lymph nodes, which is likely to cause difficulties in the initial diagnosis. Radiotherapy is the treatment of choice, however, chemotherapy has also been used. The paper describes three cases of children treated for lymphoepithelioma at the Department of Children Hematology and Oncology in Lublin between 1991 – 2001. In all cases, the diagnosis was based on histopathological examinations of the tumour or lymph node biopsies. The methods of treatment used were different in each case and the longest disease free survival was 3 years. Therefore it seems necessary to design a uniform protocol of treatment for children with lymphoepithelioma.The first child was treated only to radiotherapy. This choice was based on lack of results of well conducted trials of cytostatic treatment. The good result of our treatment confirmed the data presented by other with the use of radiotherapy alone.In the second case, in case of large tumour, paralysis of cranial nerves, this patient was refered to combined treatment (radio-chemotherapy). In this case the partial remission was achived.In the third case, chemotherapy (cisplatin + 5-fluorouracil) resulted in perfect remission of the primary tumour and metastases to the lymph nodes while radiotherapy allow to achive complete control of the primary tumour and metastases to lymph nodes.     

Diagnosis and prognosis of neuroendocrine tumours of the lung by means of high resolution image analysis.

Neuroendocrine tumours (NET) of the lung are divided in subtypes with different malignant potential. The first is the benign or low-grade malignant tumours, well-differentiated, called typical carcinoids (TC) and the second is the high-grade malignant tumours, poorly differentiated of small (SCLC) or large cell type (LCLC). Between these tumour types lies the well-differentiated carcinoma with a lower grade of malignancy (WDNEC). In clinical routine it is very important with regard to prognosis to distinguish patients with low malignant potential from those with higher ones. In this study 32 cases of SCLC, 13 of WDNEC and 14 of TC with a follow-up time up to 7 years were collected. Sections 4 microm thick from paraffin embedded tissue were Feulgen stained. By means of high resolution image analysis 100 nuclei per case were randomly gathered to extract morphometric, densitometric and textural quantitative features. To investigate the ploidy status of the tumour the corrected DNA distribution was calculated. Stepwise linear discriminant analysis to differentiate the classes and Cox regression analysis for the survival time analysis were applied. Using chromatin textural and morphometric features in two two-class discriminations, 11 of the 14 TC cases and 8 of the 13 WDNEC cases were correctly classified and 11/13 WDNEC cases and 28/32 SCLC cases, respectively. The WDNEC cases are more similar in chromatin structure to TC than to SCLC. For the survival analysis, only chromatin features were selected to differentiate patients with better and worse prognosis independent of staging and tumour type.     

Decreased monoamine oxidase (MAO) activity and MAO-A expression as diagnostic indicators of human esophageal cancers

Human esophageal cancer is a common occurring malignancy with high mortality rate partially due to lack of tools for early diagnosis. In this study, we have analysed tumour tissue from 50 cases of primary esophageal cancer. Our studies showed that the activity of monoamine oxidase (MAO) and the expression of MAO-A were strikingly decreased in the tumour tissues of 48 (96%) and 44 (88%) patients, respectively. These results suggest that the activity of MAO and the expression of MAO-A may be used as new diagnostic markers for esophageal cancers.     

Skin tests with autologous cholesteryl hemisuccinate treated tumour cells in cancer patients

Summary Skin tests with autologous irradiated tumour cells were performed in 20 malignant melanoma, 7 breast and 6 ovarian cancer patients. In the majority of cases evident reaction was noted with cholesteryl hemisuccinate (CHS)-treated cells while the reaction with untreated cells was mostly negative.No correlation was found between this reactivity and the ability of patients to be sensitized to DNCB and to their reactivity to PPD. No correlation was found between reactivity to CHS-treated tumour cells and the stage and course of the disease.     

O-9AUDIT ON BK VIRUS DETECTION IN RENAL TRANSPLANT RECIPIENTS

Introduction and Aims:  The sensitivity of bronchial cytology (brushings, washings) is in the region of 70–80%. Therefore a significant number of false negatives occur. The main aims of this study were to: (i) To identify negative bronchial washings and brushings performed in 2004 with malignant follow-up and (ii) To ascertain the cause of the false negative result where possible. 56 patients with negative bronchial cytology and subsequent malignant follow-up on a pulmonary specimen were identified. These cases formed the basis of the study.
Results:  In our series peripheral tumour location and specimen inadequacy accounted for the majority of false negative results. Malignant cells were missed in a minority of cases (5 of 56). An explanation for failure of diagnosis in 4 of the 5 cases was paucity of malignant cells. In one case of small cell carcinoma, malignant cells were abundant, but were not recognized.
Recommendations:  What can be done to reduce the false negative rate?
(1) In cases where radiology has indicated that the tumour is peripherally located patients could proceed directly to fine needle aspiration.
(2) Improved communication between clinicians and pathologists is required in relation to: (a) specimen adequacy and (b) degree of clinical suspicion.     

Chromosomal Abnormality T(9;22)(Q22;Q12) In an Extraskeletal Myxoid Chondrosarcoma Characterized By Fine Needle Aspiration Cytology, Electron Microscopy, Immunohistochemistry and Dna Flow Cytometry

A multidisciplinary approach was taken to characterize a soft tissue tumour. In smears prepared from aspirated material, uniform tumour cells, embedded in a myxoid matrix and partly arranged in a lace-like pattern, were found. Histopathology showed a lace-like pattern of cells in a matrix of hyaluronidase-stable mucins. Cytoplasmic positivity for S-100 protein was found in some tumour cells. Electron microscopic analysis revealed intracisternal aggregates of microtubules. All these features are consistent with the diagnosis of extraskeletal myxoid chondrosarcoma (EMC). DNA flow cytometry showed a diploid DNA content. Cytogenetic examination revealed the tumour karyotype 45, XY, t(2;11)(q31;p15), t(9;22)(q22.3;q12), dic(13;22)(p11;p13). Because similar 9;22-translocations have been described in two other cases of EMC, we conclude that t(9;22)(q22–31;q11–12) is a specific rearrangement in this tumour type. Cytogenetic analysis may thus be of diagnostic value in the examination of tumours with this and similar histologies.     

Benign phyllodes tumour vs fibroadenoma: FNA cytological differentiation

The differential diagnosis of fibroadenomas vs phyllodes tumours by fine needle aspiration (FNA) cytology is not possible in the majority of cases. The present study aims to look at common and dissimilar features to allow differentiation, if possible. We reviewed the FNA findings of 18 histologically proven phyllodes tumours and 18 fibroadenomas, checking in each case the epithelial features, the stromal features, and any atypia. Using a semi-quantitative score assessed by two observers we were able in most cases to distinguish a phyllodes tumour from a fibroadenoma. The most important criteria were larger stromal fragments, numerous plump stromal bare nuclei, and the higher ratio of stromal bare nuclei to epithelial bare nuclei in phyllodes tumours. In the present study, an original diagnosis of phyllodes tumour was made in 7/18 (38.9%) cases but with our criteria this could be improved to 15/18 (83.3%) cases. Therefore, the presence of specific stromal features in a dimorphic cellular pattern should suggest the correct diagnosis and differentiate its appearance from a cellular fibroadenoma.