Fine needle aspiration cytology (FNAC) of mammary granular cell tumour: a report of three cases

This report describes the FNAC findings in three cases of granular cell tumour of the breast. The patients comprised two females aged 59 and 62 years and one male aged 28 years. All patients presented with a breast lump which was clinically and radiologically suspicious of malignancy. FNAs yielded moderately cellular specimens which on cytologic examipation consisted of groups of cells and single cells with small regular nuclei and abundant granular cytoplasm. Bare nuclei were also present but these did not have the characteristic bipolar appearance of myoepithelial cells. In two cases there was a granularity to the background. The aspirates were reported as equivocal or atypical, probably benign, and surgical biopsy was performed. Histological examination showed typical benign granular cell tumours with strong positive staining for S-100 protein. Pathologists should be aware that granular cell tumour may occur in or around the breast and should consider this diagnosis in aspirates containing a population of cells with regular nuclei and abundant granular cytoplasm. The main cytologic differential diagnoses are likely to be apocrine cells and histiocytes. The suspicion of a granular cell tumour should be heightened when these features are present in an aspirate from a clinically and radiologically suspicious mass. These cases highlight the role of the triple approach encompassing clinical, radiological and cytological features in the assessment of a breast lesion.     

Role of fine needle aspiration cytology in the diagnosis of soft tissue tumours and tumour-like lesions

In this study, we evaluated the usefulness of fine needle aspiration cytology (FNAC) in the diagnosis of soft tissue tumours. We have also assessed the various pitfalls of FNAC of soft tissue tumours. This was a retrospective study and here we analysed only 82 histopathology proven cases of FNAC of soft tissue tumours diagnosed in a five and half year period. On histopathological examination, 55 of these cases were malignant and 27 were benign. There was a total of 15 recurrences and histopathology was available prior to FNAC in only eight of these cases. Therefore, excluding these eight cases, malignant tumours were primarily diagnosed by FNAC in 47 cases. The sensitivity, specificity and positive predictive value of FNAC in diagnosis of soft tissue tumours were 91.5%, 92.5% and 95.5%, respectively. Only 22 of 47 cases (46.8%) were correctly categorized. There were two false-positive and four false-negative cases. One case each of fibromatosis and schwannoma were reported as sarcoma. False-negative cases were fibrosarcoma (1), malignant nerve sheath tumour (2) and haemangiopericytoma (1). FNAC was very useful in distinguishing benign from malignant soft tissue tumours. However, it was not so effective in exact categorization of tumours.     

Warthin''s tumour: unusual vs. common morphological findings in fine needle aspiration biopsies

Fine needle aspiration biopsies (FNA) of 47 Warthin's tumours confirmed by histology were re-evaluated for cytomorphological findings. The majority of aspirates (37/47) contained a typical background with proteinaceous substance and cell debris, along with cellular elements represented by oncocytic, lymphoid, and mast cells with degranulated cytoplasm. Uncommon cellular findings were true squamous cells (1/47), atypical cells with vacuoles (1/47), osteoclastic giant cells (1/47), epithelioid cells (1/47), mast cells with preserved granules in cytoplasm (3/47), and siderophages (4/47). Uncommon findings in the background were corpora amylacea-like structures and homogeneous bright red droplets. Squamous cells and atypical cells with vacuoles caused diagnostic difficulties in distinguishing a Warthin's tumour from a squamous cell or mucoepidermoid carcinoma. However, other unusual cellular and background findings were not worrying; therefore, they are merely regarded as a curiosity in the cytomorphological appearance of the tumour.     

Diagnosis of a peripheral neuroectodermal tumour by fine needle aspiration

One case of malignant peripheral neuroectodermal tumour successfully diagnosed by cytology is presented. Although a Papanicolaou stained smear could not lead to a diagnosis more specific than a malignant small cell tumour, ancillary analytic methods performed on the cytologic material including immunocytochemistry and electron microscopy yielded the correct diagnosis of peripheral neuroectodermal tumour. This case demonstrates that a precise categorization of small round cell tumours may be achieved by cytology as long as some material is kept for immunocytochemical and ultrastructural studies.     

Loss of chromosome 1 in myxopapillary ependymoma suggests a region out of chromosome 22 as critical for tumour biology: a FISH analysis of four cases on touch imprint smears

OBJECTIVE: Ependymomas are glial tumours. They constitute approximately 5-10% of intracranial tumours and are tumours which can recur. Predictive factors of outcome in ependymomas are not well established. Karyotypic studies are relatively scarce and loss of chromosome 22 has been described to correlate with recurrence. We are unaware of any reports involving chromosome 1 aberrations in the malignant progression of ependymomas. METHODS: Cytogenetic analysis of four myxopapillary ependymomas was performed using double target fluorescent in situ hybridization (FISH), focusing on chromosomes 1 and 22. RESULTS: One patient's tumour had recurred. FISH was performed on 500 nuclei/tumours. All four cases showed a loss of chromosome 22q while only one showed an additional loss of chromosome 1p, and this was the one that recurred. CONCLUSIONS: We support the presence of a tumour suppressor gene on 1p associated with relapse in myxopapillary ependymomas and suggest that status of chromosome 1p by FISH may indicate a high-risk group of patients harbouring this tumour. More studies of this type are needed towards this direction as our results refer to a minimal number of individuals analysed.     

Peritoneal fluid cytology in serous borderline tumours of the ovary

stewart c. j. r. and kennedy j. h. (1998) Cytopathology 9, 38–45
Peritoneal fluid cytology in serous borderline tumours of the ovary
Peritoneal fluid cytology findings in three patients with serous borderline tumours of the ovary and peritoneal serous implants are presented. The specimens were characterized by papillary groups, acinar clusters and single neoplastic cells exhibiting cytoplasmic vacuolation and nuclear atypia of variable degree. The cytological appearances were initially considered consistent with ovarian adenocarcinoma in all cases. Histological correlation is required to avoid this diagnostic pitfall.     

Solitary fibrous tumour: a diagnostic challenge for the cytopathologist

N. Gupta, A. Barwad, K. Katamuthu, A. Rajwanshi, B. D. Radotra, R. Nijhawan and P. Dey Solitary fibrous tumour: a diagnostic challenge for the cytopathologist Background: Solitary fibrous tumour (SFT) is an uncommon spindle cell tumour that can occur in a variety of locations. Cytological features of this tumour have only rarely been reported in the literature. We describe the cytomorphological features of SFT with an emphasis on diagnostic pitfalls. Methods: We retrieved nine cases of histopathologically proven SFT. Three cases had sampling error with inadequate smears and, therefore, six cases with adequate cellularity were analysed for cytological findings. The cytomorphological features and the differential diagnoses on fine needle aspiration cytology (FNAC) are discussed. Results: No definitive cyto‐diagnosis of any of these cases was possible because of the morphological overlap with various soft tissue tumours and other tumour types. There was one false‐positive case, in which the possibility of sarcoma was suggested due to the presence of scattered atypical cells. Cytologically, the smears from the SFTs showed spindle to plump cells embedded in metachromatically staining dense ropy collagen material. The cells usually had oval to spindle shaped nuclei, bland chromatin and wavy elongated pale staining cytoplasm. Conclusion: A diagnosis of SFT on cytology smears is challenging. Careful attention given to certain cytological features in an appropriate clinicoradiological setting and application of immunochemistry, including CD34 and CD99 immunostaining on cytological samples, can help in the diagnosis of SFT in some cases. It is important to consider cytological overlaps of this tumour in order to avoid false‐negative or false‐positive results.     

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.     

Phyllodes tumour: cytologic and histologic presentation of 22 cases, and immunohistochemical demonstration of p53

A retrospective study of 22 cases of phyllodes tumour (PT) was undertaken to evaluate the potential value of fine needle aspiration (FNA) cytology in the diagnosis of benign and borderline PT. Histological material was available from 12 patients with typical benign PT (group 1), six patients with less typical changes (group 2) and four cases of borderline PT (group 3). Cytological presentation of PT in these cases was similar to that described by other cytologists, although abundant cellular material was obtained in only eight FNAs, naked nuclei were present in nine cases only, and atypical or suspicious cytological features were found in seven cases. Comparative analysis of p53 was made in nine patients with PT, five cases with other benign breast lesions and five with malignant lesions. p53 reaction was positive in five of nine patients with PT (all cases from groups 2 and 3), compared with two of five cases of carcinoma. p53 was negative in all patients with PT from group 1 and the five other benign cases. We suggest that cytopathologists should be careful when a myxoid stromal component is present in cytological smears.     

Diagnostic associations of p53 immunostaining in fine needle aspiration cytology of the breast

Duplicate cytospin preparations were made from 46 symptomatic breast fine needle aspirates. One of each pair was assigned to benign or malignant categories by one experienced observer as part of the 'triple approach'patient assessment. the other was immunostained with DO7, a monoclonal antibody to recombinant p53 protein, and rated by another observer as positive or negative for nuclear staining, unaware of the cytodiagnosis. Positive controls included carcinomas known to have mutant p53, while negative controls were of the reagent substitution type. of the 26 aspirates with a benign cytodiagnosis (verified by the triple approach), 23 were p53 protein-negative and three positive. of the 20 with a malignant cytodiagnosis (histologically confirmed), six were p53 protein-negative and 14 positive (exact P <0.0001). As a diagnostic test this would give 70% sensitivity and 88% specificity.     

The cytomorphologic spectrum of Wilms tumour on fine needle aspiration: a single institutional experience of 110 cases

A. Nayak, V.K. Iyer and S. Agarwala
The cytomorphologic spectrum of Wilms tumour on fine needle aspiration: a single institutional experience of 110 cases Objective: To analyse the cytomorphologic spectrum of Wilms tumour (WT) on aspirates, the largest series reported to date. Study design: Adequate aspirates from paediatric renal tumours over a period of 17 years were reviewed and selected if subsequent excision showed WT or aspirates were diagnostic for WT and clinical/radiological evidence consistent with that diagnosis. Smears were re‐examined for the proportion of components, degree of pleomorphism and mitosis. Results: Of 110 aspirates, smears were triphasic in 44 (40.0%), biphasic (blastema and tubules) in 36 (32.7%) and monophasic (blastema alone) in 30 (27.3%). Stromal predominance was seen in 11 aspirates (10.0%) and five showed rhabdomyoblastic differentiation; all 11 were triphasic. Mean mitotic rate was 9.3/5000 cells (range 4–39/5000). Nuclear atypia not amounting to anaplasia and without atypical mitoses was seen in 15 (13.6%); these presented diagnostic problems. Two aspirates (1.8%) were considered anaplastic (unfavourable), both having atypical mitoses. Criteria similar to histology (i.e. 3‐fold or more variation in nuclear size, marked hyperchromasia with bizarre nuclei and atypical mitoses in a biphasic or triphasic aspirate) helped in distinguishing anaplastic WT. Histopathological correlation in 67 cases showed good correlation of blastemal predominance, stromal predominance and anaplastic histology with the corresponding cytology. However, 9/27 (33.3%) triphasic tumours had only blastemal cells on corresponding aspiration because of sampling error. Cytokeratin was positive in 4 of 20 aspirates with blastema alone. Conclusions: Aspirates from WT were triphasic or biphasic in the majority (72.7%), permitting cytological diagnosis, which was improved by cytokeratin immunocytochemistry. Blastemal and stromal predominance on histology correlated well with cytology, but many triphasic tumours showed only blastema on aspiration. Anaplastic WT can be detected on aspirates using criteria similar to histology.     

Diagnostic dilemmas of hyalinizing trabecular tumours on fine needle aspiration cytology: a study of seven cases with BRAF mutation analysis

T. Kim, Y. L. Oh, K. M. Kim and J. H. Shin Diagnostic dilemmas of hyalinizing trabecular tumours on fine needle aspiration cytology: a study of seven cases with BRAF mutation analysis Objective: Hyalinizing trabecular tumours (HTTs) are rare follicular‐derived neoplasms that behave in an almost benign manner. HTT is frequently misdiagnosed as papillary carcinoma by fine needle aspiration (FNA) cytology or as papillary or medullary carcinoma on surgical resection. Methods: The authors examined FNA material from seven cases of histologically verified HTT. Cytological findings were reviewed and correlated with ultrasonographic and histological features. In addition, MIB‐1 and calcitonin immunostaining was performed on surgical specimens, and BRAF mutation analysis on three pre‐operative FNA specimens and seven histology specimens. Results: The original cytological diagnosis was either suspicious or positive for papillary carcinoma in all patients. The FNA‐based differential diagnoses included HTT, papillary carcinoma or, less likely, medullary carcinoma in two patients. Aspirates showed oval to spindle‐shaped cells with frequent intranuclear inclusions, isolated in loosely cohesive groups with a trabecular or syncytial pattern in a bloody background. Radiating arrangements of tumour cells surrounding hyaline stroma with serrated calcifications and a lack of papillary or sheet‐like fragments may suggest HTT on FNA. Spherical calcified bodies and possible psammoma bodies were frequently found in three cases. Retrospectively, six of the seven cases showed membranous immunoreactivity for MIB‐1, but none of the seven possessed the BRAF (V600E) mutation or showed calcitonin reactivity. Conclusions: Although the recognition of HTT on FNA cytology is difficult, because of its morphological similarities to papillary and medullary carcinoma, its characteristic cytological features along with ultrasonographic findings may suggest the diagnosis preoperatively and avoid surgical over‐treatment.     

Fine needle aspiration cytology of solitary fibrous tumours of the pleura

OBJECTIVE: To analyse fine needle aspirates from solitary fibrous tumour (SFT) of the pleura and to elucidate the cytological features unique to these tumours and differential diagnostic findings of benign and malignant SFTs. METHODS: Fine needle aspiration (FNA) cytology slides from eight cases of SFT of the pleura, including six benign and two malignant SFTs, were reviewed. The subsequent histological slides were also examined. RESULTS: Cytological diagnoses from six histologically proven cases of benign SFTs were low-grade sarcoma (one), non-small cell carcinoma (one), malignant tumour (1) and benign (three). Two cases of malignant SFTs were cytologically diagnosed as malignancy. The aspirates showed a varying degree of cellularity. Most smears were composed of single, scattered fusiform cells, and irregular loose aggregates of oval to spindle cells intimately admixed with dense collagenous stroma. Two malignant SFTs had a greater number of cells in clusters, and displayed mitotic activity, without significant cytological atypia. CONCLUSIONS: The diagnosis of SFT may be suggested by a combination of cytological and radiological findings. The precise determination of malignancy for SFT, however, is not usually straightforward on the basis of cytological features alone. The findings of highly cellular clusters and mitotic activity in the FNA cytological smear can help differentiate malignant from benign SFTs.     

Acinic Cell Tumour: A Metastasis In the Lung Diagnosed By Electron Microscopy of Aspirated Material

A case of acinic cell carcinoma, metastatic to lung is presented. Fine needle aspiration showed a low-grade adenocarcinoma. Electron microscopy of the aspirated material, however, allowed definite preoperative diagnosis of metastatic acinic cell carcinoma. The lesion was successfully resected and diagnosis confirmed on histology. Ten years previously an acinic cell carcinoma of similar histology had been excised from the left parotid region.