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.     

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.     

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.     

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.     

Cytomorphological study of soft tissue neoplasms: role of fluorescent immunocytochemistry in diagnosis

OBJECTIVES: Exact categorization of soft tissue tumours (STTs) on smears requires application of various ancillary techniques. This study was aimed at evaluating the role of fluorescent immunocytochemistry (FICC) in cyto-diagnosis of 30 STT cases. METHODS: Thirty cases of soft tissue tumours were included in the present study. All cases were subjected to routine Giemsa and Papanicolaou stain. Extra smears were made and kept for fluorescent immunostaining. A panel of cytoskeletal antibodies, tagged with FITC (Fluorescein isothyocynate), was employed in all these cases. Fluorescent immunostained smears were examined under Zeiss Confocal Laser scanning microscope, using double immunofluorescence (red-green). Finally, all cases were subjected to biopsy and again immunoperoxidase staining. RESULTS: Among the 30 cases in the present study, unaided cytological diagnoses ranged from 'spindle cell' tumour in four (13.3%) cases, benign and malignant spindle cell tumour in 17 (56.6%) cases, to malignant mesenchymal tumour in nine (30%) cases. FICC helped in further correct categorization of 25/30 (83.3%) cases viz. leiomyoma (three), benign neurogenic tumour (six), schwannoma (one), dermatofibrosarcoma protuberans (three), synovial sarcoma (two), rhabdomyosarcoma (two), malignant fibrous histiocytoma (five) and malignant peripheral nerve sheath tumour (three). Aggressive fibromatosis was found to be a missed diagnosis in two cases. Overall concordance between cyto-diagnosis with FICC, and histopathology results was 83.3% (P < 0.05). CONCLUSION: Fluorescent immunocytochemistry is a significant ancillary technique for making a rapid and specific diagnosis of STT, as required for their timely management. Incorporation of a wide panel of antibody markers with clinico-cytological correlation is recommended in forming an exact diagnosis in these cases.     

Fine needle aspiration biopsy of three cases of squamous cell carcinoma presenting as a thyroid mass: cytological findings and differential diagnosis

M. Rosa and K. Toronczyk Fine needle aspiration biopsy of three cases of squamous cell carcinoma presenting as a thyroid mass: cytological findings and differential diagnosis Objective: Primary squamous cell carcinomas of the thyroid gland are extremely rare, comprising about 1% of thyroid malignancies. Although squamous cell carcinomas are readily identified as such on aspiration cytology in the majority of cases, the differentiation of primary versus metastatic tumour might not always be easy. Herein, we report three cases of squamous cell carcinomas involving the thyroid gland. Methods: Fine needle aspiration cytology (FNAC) was performed in three patients with a thyroid mass using standard guidelines. Smears were stained with Diff‐Quik and Papanicolaou stains. Results: Two patients were male and one was female, aged 59, 45 and 35 years, respectively. In all three patients a thyroid mass was present. FNAC smears in all cases showed cytological features of squamous cell carcinoma including keratinization and necrosis. After clinical and cytological correlation, one case appeared to be primary, one case metastatic, and in the third case no additional clinical information or biopsy follow‐up was available for further characterization. Conclusions: Because primary squamous cell carcinoma of the thyroid is a rare finding, metastatic squamous cell carcinoma should always be excluded first. Metastatic disease usually presents in the setting of widespread malignancy, therefore a dedicated clinical and radiological investigation is necessary in these cases. In both clinical scenarios the patient’s prognosis is poor.     

Role of fine needle aspiration cytology in the diagnosis and management of Warthin’s tumour of the salivary glands

J. M. Viguer, B. Vicandi, J. A. Jiménez‐Heffernan, P. López‐Ferrer, P. González‐Peramato and C. Castillo
Role of fine needle aspiration cytology in the diagnosis and management of Warthin’s tumour of the salivary glands Objective: Local excision surgical procedures and non‐surgical conservative management are considered alternatives to superficial parotidectomy in the treatment and management of Warthin’s tumour (WT). Such therapeutic alternatives demand accurate diagnosis. In order to determine whether fine needle aspiration cytology (FNAC) is capable of rendering such a minimally invasive diagnosis, we evaluated its accuracy and diagnostic parameters in a large series of histologically proven cases of WT. Methods: A cytohistological study of 116 salivary tumours from 110 patients (four WT were bilateral) with a histological or cytological diagnosis of WT. Results: Histology confirmed the cytological diagnosis in 103 of 114 tumours (90.4%). Two tumours were incorrectly diagnosed on cytology as WT. In 11 cases of WT there was an erroneous or non‐representative cytological diagnosis. The sensitivity was 90.4%, and positive predictive value 98.1%. Regarding malignancy, there were three misdiagnoses. One tumour diagnosed as WT was a low‐grade mucoepidermoid carcinoma. Two cases considered ‘suspicious of squamous cell carcinoma’ corresponded to WT. After review, 81.3% of the cases of WT were considered typical and 18.7% non‐typical; all misdiagnoses were in the latter group. Cytological difficulties could be divided into three areas: (i) absence of one or more diagnostic components; (ii) ‘squamoid’ pattern; and (iii) mucinous metaplasia. Degenerated oncocytes were present in 65% of cases. Conclusions: FNAC offers the possibility of a reliable diagnosis of WT. Pathologists must pay attention to the squamous appearance of degenerated oncocytes. Cytology, when coupled with clinical and image findings, may permit conservative tumour management.     

Medullary Carcinoma of Thyroid: A Re-Evaluation of the Cytological Criteria of Diagnosis

We have reviewed the fine needle aspiration cytology appearances of a series of 31 consecutive and histologically confirmed medullary carcinomas of the thyroid. Despite the absence of a totally specific diagnostic feature, this retrospective re-evaluation indicates that a preoperative diagnosis of medullary carcinoma of the thyroid is possible in almost every case. The features occurring most commonly include a dispersed cell pattern in which round or spindle shaped cells with eccentric speckled nuclei were seen showing slight pleomorphism with inconspicuous nucleoli. In a third of cases fine red granularity was present in the cytoplasm in slides stained with Giemsa and by the Papanicolaou technique.     

Fine needle aspiration at a Regional Head and Neck Clinic: A clinically beneficial and cost-effective service

Background:  Fine needle aspiration (FNA) is an important adjuvant to the diagnosis of a palpable lesion which often permits the complete assessment of patients. The main objective of this study was to determine the clinical benefit of a dedicated FNA service at a tertiary referral Head and Neck Clinic and to assess if such a service is cost effective.
Methods:  All patients attending the Head and Neck Clinic during 2004 were prospectively assessed in this study. Patient records were analysed regarding investigative modalities including FNA, the subsequent cytology result and the requirement for further histopathological investigations. A cost analysis for all investigative procedures was performed.
Results:  A total of 135 patients (36 males) had FNAs performed during the study period. The median age was 51.5 years (range 17–92). Patients presented with lesions of lymph nodes ( n  = 46), thyroid ( n  = 41), salivary, parotid or submandibular glands ( n  = 22) and other cutaneous or cystic lesions ( n  = 26). Cytological grading results were; C1 = 26, C2 = 93, C3 = 8, C4 = 2 and C5 = 6. Patients with lesions C3 or above normally proceeded to further investigations. The overall cost of the FNA per episode in the out-patient clinic was £114 per episode compared to day case open biopsy per patient of £333 and an in-patient stay per patient was £2371. FNA provided sufficient pathological diagnosis to avoid day case surgery in 57 patients (42.2%), and inpatient surgery in 65 patients (48.1%) resulting in a total saving of £158 372 in 2004.
Conclusion:  This study demonstrates the clinical benefit and cost-effectiveness of FNA services in a dedicated Head and Neck clinic.     

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.     

Role of fine needle aspiration cytology in the diagnosis of soft tissue tumours

Fine needle aspiration cytology (FNAC) is a widely accepted safe, simple and rapid diagnostic procedure used in the examination of neoplastic and non‐neoplastic lesions of various locations. Since its introduction, FNAC has developed into an effective diagnostic tool practiced in a large majority of medical centres evaluating and treating oncological patients. The role of FNAC has been limited in the examination of primary soft tissue lesions, however, as many physicians working in this area recommended against using FNAC. An increasing use of minimally invasive diagnostic procedures in the last decade has resulted in a better acceptance of FNAC as a first‐line approach or as a complementary tool to core needle biopsy in the diagnosis of musculoskeletal lesions. This review discusses the role and value of FNAC in the evaluation and treatment of soft tissue tumours based on the experience gathered over the course of 48 years at the Sarcoma Center in Lund, Sweden. FNAC reports most often provide diagnostic information allowing the initiation of treatment or, when definitive diagnosis cannot be rendered from a cytological examination, guiding the continued diagnostic investigation. The main advantages of soft tissue FNAC are good sensitivity and specificity, low morbidity, speed of diagnosis, and low cost/benefit ratio. The most important disadvantages stem from limited experience in cytological diagnosis of soft tissue tumours and a lack of standardised and uniform reporting system for soft tissue FNAC.     

EMMPRIN (CD147) expression and differentiation of papillary thyroid carcinoma: implications for immunocytochemistry in FNA cytology

Y. Aratake, K. Marutsuka, K. Kiyoyama, T. Kuribayashi, T. Miyamoto, K. Yakushiji, S. Ohno, Y. Miyake, T. Sakaguchi, T. K. Kobayashi, A. Okayama, K. Tamura and E. Ohno
EMMPRIN (CD147) expression and differentiation of papillary thyroid carcinoma: implications for immunocytochemistry in FNA cytology Objective: Extracellular matrix metalloproteinase inducer (EMMPRIN) and its induced matrix metalloproteinases (MMPs) play a crucial role in tumour progression, invasion and metastasis. EMMPRIN expression has been demonstrated in several tumours, but its expression profile in thyroid cancer remains unclear. Methods: We evaluated the expression profile of EMMPRIN at various stages of differentiation of thyroid carcinoma, including 20 cases of well‐differentiated papillary carcinoma (WDPC), 15 cases of papillary carcinoma with a poorly differentiated carcinoma component (PC/PDC) and four cases with an undifferentiated carcinoma (UDC) component, using paraffin‐embedded sections for immunohistochemical stains. Also, we used 32 fine needle aspiration cytology and imprint smears from the same cases for immunocytochemical stains. The staining results were evaluated with a scoring system. Results: Immunohistochemical staining showed that EMMPRIN expression was absent or weak in almost all WDPC specimens, whereas it was moderate or strong in PDC and UDC components. In tumours that showed a gradual morphological transformation from WDPC to PDC components, the expression of EMMPRIN was progressively stronger from the areas of WDPC to those of PDC. WDPC, PC/PDC and UDC had expression scores of 4.9, 45.0 and 245.7, respectively. Results of immunocytochemical staining showed almost the same staining profile as those of immunohistochemical staining. The cytological atypia of EMMPRIN‐positive cells was greater than that of negative cells. Conclusion: These results indicated that EMMPRIN expression correlates significantly with the degree of dedifferentiation of thyroid carcinoma. This study demonstrates the feasibility of expression of EMMPRIN using fine needle aspiration samples. Therefore, immunocytochemical analysis of EMMPRIN may be a novel aid to evaluate the differentiation of thyroid carcinoma.     

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.     

Peripheral neuroectodermal tumour (neuroepithelioma) of the thoracopulmonary region: light and electron microscopic cytology

We describe a case of peripheral neuroectodermal tumour of the thoracopulmonary region diagnosed by fine needle aspiration cytology. Light microscope examination revealed numerous small tumour cells arranged in large irregular aggregates occasionally delimiting empty vascular-type spaces or forming rosette-like structures. Cytologically the tumour cells showed a marked degree of nuclear anaplasia, scanty cytoplasm and long thin cytoplasmic processes. Electron microscopy revealed cells with characteristics of neuroectodermal differentiation.     

Clear cell sarcoma, cellular mesoblastic nephroma and metanephric adenoma: cytological features and differential diagnosis with Wilms tumour

Wilms' Tumour (WT) is the most common kidney tumour in childhood, this fact and the embryonic complexity of WT create, whenever one of its three classical components predominates in cytologic smears, difficulties in the differential diagnoses with other less common entities. In the present study, we review the cytological and immunohistochemical characteristics of three children renal tumours, a Clear Cell Sarcoma of the Kidney (CCSK-case1), a Cellular Mesoblastic Nephroma (CMN-case2) and a Metanephric Adenoma (MA-case3) and compare them, for differential diagnostic purposes, with smears of blastematous, mesenchymal and epithelial predominant WTs, previously diagnosed in our Department. In all cases a mass was detected in the abdomen (2 and 8 year old children-cases 1 and 3, respectively), and pre-birth in case 2 (the tumour was detected during pregnancy). Fine needle biopsy was performed followed by routine cytologic examination. The presence of moderate amount of blue pale cytoplasm in neoplastic cells (case1), the presence of tightly cohesive, bland, spindle tumour cells (case2) and the identification of small, well differentiated epithelial tubules with psammoma bodies in case 3, were the main morphologic characteristics that we think represent the most important elements for distinguishing our cases from a WT. Immunoreactivity was only helpful in case 1 as we found a characteristic dot-like pattern positivity for vimentin, in the absence of immunoreactivity for the other markers that are usually positive in WT. Summing up, these three cases demonstrate that cytopathologists should be aware of the occurrence of uncommon renal neoplasms in childhood and should be acquainted with their characteristics, in order to avoid false diagnoses.     

Fine needle aspiration (FNA) in the diagnosis of soft tissue tumours; a review of 22 years experience

FNA plays an important role in preoperative diagnosis of soft tissue tumours. A close clinical/morphologic cooperation is essential. FNA should be performed on the most accessible part of the tumour, avoiding penetration of the deep portions of the tumour. Needles 0.7 mm (22 G) are recommended. For deep lesions, needles with a stylet should be used. After the FNA, tattooing of the aspiration channel is recommended, and the channel is surgically removed together with the tumour, if a sarcoma. Material from the FNA can be used for additional examinations, i.e. electron microscopy, immunohistochemistry, DNA ploidy analysis and chromosomal analysis. Those techniques are of great importance in the differential diagnosis, particularly in the paediatric small/round cell tumours. the majority of sarcomas can be defined as low grade or high grade malignant in FNA. For malignancy grading the following parameters are used: cellularity, pleomorphism, chromatin pattern, nucleolar structure, mitotic figures and necroses. Cytodiagnostic details of the most common soft tissue tumours and their differential diagnoses are presented.