Methodologic aspects of evaluating brush samples from biliary strictures by cytology and DNA flow cytometry

OBJECTIVE: To present a method of increasing the cell yield from brush samples of the biliary tree for measurement of DNA content by flow cytometry (FCM). STUDY DESIGN: One hundred eight cell specimens from 86 patients were studied by FCM for DNA ploidy and cell cycle composition. All specimens were cytologically classified into benign, suspicious for malignancy and malignant. Two methods for preparation of the cell material were compared. RESULTS: Enzymatic treatment of formalin-fixed brushes for release of cell nuclei was superior to mechanical removal of the cells. The fraction of samples not possible to assess was reduced from 27% to 4%, and good quality histograms increased from 21% to 62%. Aneuploidy was detected in 7% of benign and 57% of suspicious malignant samples. Using DNA analysis in addition to cytology as a diagnostic marker for cancer, the sensitivity increased from 12% to 31%. CONCLUSION: FCM of cells from biliary strictures can be used routinely as an adjunct to cytology for DNA analysis.     

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.     

Cytologic findings of breast ductal lavage and concurrent fine needle aspiration in pleomorphic lobular carcinoma in situ: a case report

BACKGROUND: Breast ductal lavage (DL) is a noninvasive procedure for sampling ductal epithelial cells. Patients at risk for breast cancer or with prior history can be monitored by DL. This report compares cytomorphology in concurrent DL, fine needle aspiration (FNA) and histology in a case of pleomorphic lobular carcinoma in situ (PLCIS) with signet ring features. CASE: A 57-year-old woman had DL and FNA performed after quadrantectomy for lobular carcinoma in situ with signet ring cell features. DL and FNA were diagnosed as suspicious and positive for malignancy, respectively. Subsequent biopsy showed PLCIS. Cytomorphologic features of DL, FNA and histology were compared. DL showed epithelial cells in small clusters or single-file arrangement and single-lying; in FNA, single cells predominated. DL and FNA showed nuclear atypia and cytoplasmic vacuoles, the latter more prevalent in FNA. Both samples showed cells with signet ring features. The atypical epithelial cells present in DL and FNA were identical to those seen in the histologic material. CONCLUSION: Cytomorphologic findings in DL, although less striking, are comparable to those seen in FNA. Architecture, nuclear atypia and intracytoplasmic vacuoles are helpful features in DL for establishing a diagnosis of suspicious if not positive for malignancy in LCIS.     

Endoscopic cytology and biopsy in the diagnosis of gastroesophageal malignancy

Direct-vision endoscopic cytologies and biopsies were performed on 1,437 patients during a five-year period, and the incidence, correct typing and diagnosis of gastroesophageal cancer were studied. At the first cytology, malignant cells were diagnosed in 80 cases, all of which were confirmed by the endoscopic biopsy; in 30 cases, despite suspicious cytology, no malignancy was seen at the first biopsy. At repeat endoscopic cytology and biopsy, however, 21 of these 30 cases were correctly correlated for malignancy, resulting in a final correct correlation in 101 of the 110 cases (91.8%) and a diagnostic discrepancy in 9 cases (8.2%). It thus appears that the procedure is useful in diagnosing gastroesophageal cancer in the majority of cases. In the cases of discrepancies, gastric ulcers were found later; the repeatedly suspicious cytologies were due to the cytologic atypia of the cells from regenerating hyperplastic and/or metaplastic epithelium at the margins of the ulcers. Such cells showed a wide spectrum of changes, ranging from mild atypia to severe atypia mimicking adenocarcinoma of the upper gastrointestinal tract.     

The utility of transbronchial (Wang) fine needle aspiration in lung cancer diagnosis

We evaluated our experience with transbronchial fine needle aspiration (TBNA) in cancer diagnosis over a period of 1 year. A total of 51 aspirates were performed by specialist chest physicians in the presence of a cytopathologist who made on spot evaluation of Diff-Quik smears for adequacy and guided the aspirator for additional sampling if necessary. Two clusters of at least 10 malignant cells were required on the Diff-Quik smears to render an on the spot positive diagnosis of malignancy. Aspirates showing atypical cells or few malignant cells not fulfilling the above criteria were placed in a suspicious category and additional material was requested. The TBNA results were correlated with the transbronchial biopsy when available.     

Diagnostic value of nucleolar organizer regions (AgNORs) in brush biopsies of suspicious lesions of the oral cavity.

OBJECTIVE: The aim of this retrospective study was to report on the diagnostic accuracy of AgNOR-analysis as an adjunctive diagnostic tool of conventional oral exfoliative cytology taken from suspicious lesions in our clinic. STUDY DESIGN: Cytological diagnoses obtained from brush biopsies of macroscopically suspicious lesions of the oral mucosa from 75 patients (final diagnoses: 53 histologically proven squamous cell carcinomas, 11 leukoplakias and other inflammatory oral lesions) and from 11 patients with normal mucosa as a negative control group were compared with histological and/or clinical follow-ups. Five smears were doubtful and seven suspicious for tumor cells in the cytologic report. Number of AgNOR's were counted in 100 squamous epithelial cell-nuclei per slide after silver-restaining. RESULTS: Sensitivity of our cytological diagnosis alone on oral smears for the detection of squamous carcinomas was 92.5%, specificity 100%, positive predictive value was 100% and negative 84.6%. The best cut-off value of the mean number of AgNOR dots per nucleus distinguishing benign from malignant cells was 4.8. The percentage of nuclei with more than three AgNORs had a cut-off level of 70%. Applying these methods to twelve doubtful or suspicious cytological diagnoses we were able to correctly establish the diagnosis of malignancy in ten cases of histologically proven cancers and to reveal benignity in two histologically proven cases. Thus we achieved a positive and negative predictive value of 100% each. CONCLUSIONS: Smears from brushings of visible oral lesions, if clinically considered as suspicious for cancer, are an easily practicable, non-invasive, painless, safe and accurate screening method for detection of oral cancerous lesions. We conclude that AgNOR-analysis may be a useful adjunct to other methods in routine cytological diagnosis of oral cancer that can help to solve cytologically suspicious or doubtful cases.     

Endoscopic ultrasound-guided FNA biopsy of bile duct and gallbladder: analysis of 53 cases

OBJECTIVE: Endoscopic retrograde cholangiopancreaticography (ERCP)-guided brushing has been the standard of practice for surveillance and detection of carcinoma in the biliary tree. Few studies have evaluated the role of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) in diagnosing clinically suspected cholangiocarcinoma. The role of this method in diagnosing clinically suspected gallbladder malignancies has not been extensively evaluated in the USA. This study investigates the role of EUS-FNA in the diagnosis of clinically suspected biliary tree and gallbladder malignancies in a large patient series. METHODS: EUS-FNAs were obtained from 46 bile duct and seven gallbladder lesions. On-site rapid interpretation was provided using air-dried Diff Quik stained smears. In addition, alcohol fixed Papanicoloau stained smears and Thin Prep preparations (Cytye Corp., Marlborough, MA, USA) were evaluated before providing a final cytological diagnosis. Tissue biopsies and/or clinical follow-up were used as the standards to determine operating characteristics for EUS-FNA. RESULTS: The mean ages for bile duct and gallbladder lesions were 66 years (range: 37-84 years), and 69 years (range 49-86 years), respectively. All cases diagnosed as suspicious/malignant on preliminary evaluation were confirmed on final cytological interpretation (27/27). The operating characteristics show that EUS-FNA is highly specific (100%) with sensitivity rates of 87% and 80% from clinically suspected malignancies of biliary tract and gallbladder, respectively. Sampling error in three cases and associated acute inflammation in two cases resulted in false-negative diagnoses. CONCLUSIONS: EUS-FNA of biliary tree and gallbladder carcinoma is highly specific and should be considered for evaluation of clinically suspicious lesions. Marked inflammation may result in false-negative diagnoses.     

Cervical and peritoneal fluid cytology of uterine sarcomas

OBJECTIVE: To study the cytologic features of uterine sarcoma. STUDY DESIGN: The pathology records of 102 patients with uterine sarcoma were reviewed. Four patients, including one case of leiomyosarcoma (LMS), one high grade stromal sarcoma (HGSS) and two malignant mixed müllerian tumor (MMMT), had abnormal cervical and/or peritoneal cytologic findings. Three abnormal cervical smears and two abnormal peritoneal fluids from these patients, including immunohistochemically stained sections of cell block, were reviewed. RESULTS: The diagnostic cells appeared in clusters or in isolation. They had enlarged and hyperchromatic nuclei. Occasional mitotic figures were seen. The cells were considered suspicious for malignancy in cervical smears of HGSS and in the peritoneal fluid of LMS. Adenocarcinoma cells were identified in both the cervical smear and peritoneal fluid of one patient with MMMT. Atypical cells were found in another patient with MMMT. CONCLUSION: Positive cervical or peritoneal cytology is uncommonly detected in association with uterine sarcomas. Even when abnormal cells are found, it may be difficult to give a definitive diagnosis of uterine sarcoma based directly on the cytomorphologic characteristics of cervical or peritoneal smears. However, such a possibility should be kept in mind by the cytopathologist to avoid missing the diagnosis.     

Thyroid Bethesda reporting category, ‘suspicious for papillary thyroid carcinoma’, pitfalls and clues to optimize the use of this category

A. Mahajan, X. Lin and R. Nayar Thyroid Bethesda reporting category, ‘suspicious for papillary thyroid carcinoma’, pitfalls and clues to optimize the use of this category Objective: The Bethesda System of Reporting Thyroid Cytopathology classifies the indeterminate categories based on their differing risks of malignancy, as atypia of undetermined significance (AUS), follicular neoplasm/suspicious for follicular neoplasm (FLUS) and suspicious for malignancy. The vast majority of cases of the last category are suspicious for papillary thyroid carcinoma (PTC). The aim of the present study was to identify the pitfalls and clues to improve the usage of the suspicious category as well as improve its outcome of malignancy. Methods: We reviewed the cytological features on air dried Diff‐Quik® and alcohol‐fixed Papanicolaou smears from 54 thyroid fine needle aspirates (FNAs) with surgical follow‐up that were originally diagnosed as suspicious. Procedure data/specimen adequacy was correlated and follow‐up histology reports were reviewed after our cytological review was completed. Incidental PTC that was not the target of the FNA was excluded from the calculations for correlation. Results: In our cytological review, we retained a diagnosis of suspicious in 18 of the 54 cases and the remaining 36 were re‐categorized as follows: 6 malignant, 10 neoplasm (which is used in our centre instead of FLUS) and 20 AUS. The reasons for overcall of suspicious cases included pseudopapillae, syncytial sheets, nuclear grooves and pinpoint nucleoli in chronic lymphocytic thyroiditis and Hürthle cell neoplasms, and intranuclear inclusions in parathyroid adenoma, hyalinizing trabecular adenoma and mesenchymal repair. The primary reasons for undercall of PTC as suspicious included cystic aspirates with minor features of PTC such as histiocytoid cells, bubblegum colloid, syncytial sheets and cellular swirls. Cases with cytoplasm similar to Hürthle cells were also noted to cause difficulty in accurate classification. Conclusions: Recognition of these pitfalls and clues can help improve diagnosis, patient treatment and consequently reduce the number of unnecessary thyroidectomies.     

Fibromatosislike metaplastic carcinoma of the breast as a diagnostic pitfall for fine needle aspiration cytology: a case report

BACKGROUND Metaplastic carcinomas of the breast are uncommon, and most display marked cellular atypia. Recently, a low grade fibromatosis-like metaplastic carcinoma was found and displayed little nuclear atypia. CASE A 74-year-old woman presented with a 2.5-cm, palpable breast nodule. Mammogram was reported as suspicious for malignancy. Cytologic examination revealed smears of low cellularity with most cells lying in clusters and having a round or oval shape. Rare cells had a "spindle" shape. Nuclear features were low grade. Rare individual cells had retained cytoplasm. Lumpectomy revealed a fibromatosis-like metaplastic carcinoma. CONCLUSION: Cytologically, fibromatosis-like metaplastic carcinomas are low grade lesions producing smears of relatively low cellularity. Separation from ductal carcinomas is necessary because fibromatosis-like metaplastic carcinomas rarely metastasize to lymph nodes.     

O-9Uncommon subtypes of borderline nuclear changes: cytological features and predictive value

Introduction:  To establish the significance of cytological features which could predict clinically significant endometrial pathology, and therefore guide reporting practice in cervical samples.
Methods:  A retrospective review of SurePath liquid-based cytology (LBC) cervical samples between 2002 and 2006, obtained at screening and colposcopy. These smears contained normal endometrial cells present at inappropriate times of the menstrual cycle, endometrial cells with atypia (borderline change) and with features suspicious / diagnostic of endometrial carcinoma (glandular neoplasia). False negative and false positive cases detected on subsequent histology were also included. The control group comprised negative samples and a few abnormal smears. All smears were randomly assigned and blinded to menopausal status, age, use of oral contraceptive pill and hormone replacement therapy and presence of intrauterine device. Each smear was reviewed for 16 cytologic criteria and a cytological diagnosis was given for each.
Results:  A total of 219 smears were available for review; 137 were negative, out of which 85 contained normal endometrial cells, 41 contained endometrial cells with atypia, 10 contained endometrial cells with features suggestive of adenocarcinoma and 31 contained endometrial cells with features diagnostic of adenocarcinoma. The feature most associated with benign endometrial cells is top hat with central cell condensation. In contrast, the features associated with malignant endometrial cells are smooth nuclear membrane, pale chromatin, small nucleoli and scalloped borders.
Discussion:  The criteria identified in this study do not definitively define a neoplastic process, but appear to be helpful in individual cases. This study emphasises that endometrial changes should be always interpreted with the relevant clinical information, which would otherwise lead to overdiagnosis in premenopausal women.     

Reclassification of "atypical" diagnoses in endoscopic retrograde cholangiopancreaticography-guided biliary brushings

OBJECTIVE: To evaluate the usefulness of reclassifying "atypical" diagnoses in reporting biliary cytology using strict morphologic criteria. STUDY DESIGN: Cytologic specimens from 139 patients (direct, alcohol-fixed smears or cytocentrifuge preparations) were evaluated. Diagnoses were benign (70), atypical (36) and malignant (33). Using strict criteria--major (nuclear contour, chromatin pattern) and minor (polarity, cell types, nuclear size, nuclear grooves, nucleoli, mitosis, nuclear/cytoplasmic [N/C] ratio)--atypical cases were reevaluated and reclassified. Follow-up (F/U) was available on all cases. RESULTS: Atypical cases, (36) were reclassified as malignant (26), atypical favor benign (2)/reactive (3) and atypical, not otherwise specified (NOS) (5). Cases reclassified as malignant showed irregular nuclear contours, chromatin irregularities and rare mitosis. Nuclear enlargement, nucleoli and cellularity varied widely in all groups. N/C ratio was increased in most reclassified malignant cases. All 26 malignant reclassifications correlated with F/U of malignancy. Benign and reactive cases (5) were negative for malignancy on F/U (4), and in 1 case a metastatic carcinoma involving the biliary tree was found. In the 5 atypical (NOS) cases, F/U showed malignancy (3) and pancreatitis (2). Cytocentrifuge preparations made in our laboratory were of superior quality when compared to other methods of cell preparation. CONCLUSION: Irregularities in nuclear membrane and abnormal chromatin pattern were the most consistently useful features correlating with malignancy. The sensitivity and specificity of biliary brush cytology can be enhanced by using strict cytomorphologic criteria and proper collection and fixation, all of which decrease atypical diagnoses.     

Comparative cytology of mucocelelike lesion and mucinous carcinoma of the breast in fine needle aspiration

OBJECTIVE: To study the fine needle aspiration cytology (FNAC) features of mucocelelike lesion (MLL) of the breast and to compare them to those of mucinous carcinoma. STUDY DESIGN: The fine needle aspiration (FNA) smears of 7 cases of histologically proven MLL (2 malignant and 5 benign, including 4 associated with atypical ductal hyperplasia) were reviewed and compared to those of 14 mucinous carcinoma cases. RESULTS: In all cases, grossly visible thick, mucoid material was obtained from FNA. The most important features for distinguishing benign MLL from mucinous carcinoma were: (1) scant cellularity; (2) no or rare single, intact tumor cells; (3) tumor cells arranged in cohesive monolayers; and (4) absence of significant nuclear atypia. In contrast, mucinous carcinoma in general showed higher cellularity; abundant single, intact cells; three-dimensional cellular clusters in most cases; and nuclear atypia ranging from mild to severe. CONCLUSION: Mucinous lesions of the breast should be divided into MLL and frank mucinous carcinoma based on FNAC. However, FNAC diagnosis of malignant MLL has yet to be defined. Excisional biopsy is advised for all hypocellular cases for further separation into benign and malignant MLL and to rule out the possibility of hypocellular mucinous carcinoma.     

Abrasive bronchial brushing cytology. A preliminary study of 200 specimens for the diagnosis of neoplastic and nonneoplastic bronchopulmonary lesions

Two hundred subjects with chronic respiratory symptoms with a suspicion of malignancy were selected for bronchial brushing cytology. Prior sputum examination had shown malignant squamous cells in two cases only. The cytologic appearances of the brushing smears were divided into five categories: 41 (20.5%) smears with positively malignant cells; 20 (10%) smears predominantly showing chronic inflammatory features; 31 (15.5%) smears with mainly acute inflammatory changes; 60 (30%) smears with normal cytologic features; and 48 (24%) smears unsatisfactory for cytologic interpretation. Thirteen patients with a positive cytology had a positive tissue biopsy for malignancy. Among the group with chronic inflammatory changes, acid-fast bacilli were identified in nine cases, and one smear showed frank tuberculous granuloma. In the unsatisfactory group, two cases showed malignant cells in the postbrushing sputum. There was one false-negative report for malignancy in the entire study. This study confirms the sensitivity and accuracy of bronchial brushing cytology in the diagnosis of various bronchopulmonary lesions, especially malignancy and pulmonary tuberculosis, in India.     

Aspiration cytology of breast cysts

A cytologic evaluation was made of 57 samples of fluid aspirated from cystic breast masses during the past 12 years in our hospital. The cytologic diagnosis of the cyst aspirates from 17 cancer cases was positive in 10 cases, suspicious in 2 and negative in 5. No false-positive cytologic diagnosis was made in 40 cases of benign cystic disease. Blood-tinged aspirates were observed in 14 of the 17 cases of malignant cystic disease but in only 2 of 40 benign cases. Ductal cell clusters were detected in aspiration smears from 16 of the cases of malignant cystic disease and 15 of the cases of benign cystic disease. Apocrine cells were seen in the aspiration smears from 12 of the cases of benign cystic disease but in none of the aspirates from the 17 cancer cases.     

Diffuse alveolar damage. Morphologic features in bronchoalveolar lavage fluid

OBJECTIVE: To evaluate the overall cytologic characteristics of diffuse alveolar damage (DAD) in bronchoalveolar lavage (BAL) specimens in search of features that could be useful in cytologic diagnosis. STUDY DESIGN: We evaluated BAL samples from patients with DAD obtained simultaneously with transbronchial biopsies (n = 8) or open lung biopsies (n = 2) or within 24 hours of autopsy (n = 2). The material was processed routinely for cytologic and histologic evaluation. RESULTS: The smears were moderately to highly cellular. All cases had large numbers of alveolar macrophages and/or desquamated alveolar cells. The epithelial component displayed various degrees of nuclear atypia. Some epithelial clusters were three-dimensional, with peripheral cells showing clear cytoplasm, protruding outwards and resembling hobnails. Other aggregates appeared two-dimensional, as sheets of cells with flattened and dense cytoplasm (squamotized). Both types of cell clusters were often associated with dense, basophilic or amphophilic, amorphous extracellular material. Counterparts of all the cytologic features were observed in the histologic material, including atypia of the alveolar lining with hobnailing, squamotization, amorphous extracellular material and hyaline membranes. CONCLUSION: The cytologic features of BAL represent a constellation of alveolar cell injury. Based on these features, DAD can be correctly diagnosed or suggested in BAL samples in the appropriate clinical setting.     

Fine needle aspiration of the liver. Significance of hepatocytic naked nuclei in the diagnosis of hepatocellular carcinoma

Fine needle aspiration (FNA) smears from 60 cases of histologically (34) or clinically (26) confirmed hepatocellular carcinomas were reviewed. In about 90% of the cases, the cytologic preparations contained clusters of malignant cells with variable degrees of hepatocytic features and a distinctive type of naked nuclei. These naked nuclei had features similar to those of the malignant hepatocytes, but with more evident atypia. They were numerous in about 75% of the cases and less frequent in 15%; in three cases, they were practically absent. All three cases of well-differentiated hepatocellular carcinomas presented with numerous naked nuclei with slight atypia. Flowerlike-configured naked nuclei were especially found in poorly differentiated hepatocellular tumors. Hepatocytic naked nuclei were rarely found in FNA smears from normal liver, metastases, cysts or degenerative, regenerative and inflammatory liver processes; when seen in these cases, they showed no atypia. The presence of atypical hepatocytic naked nuclei appears to be a very useful criterion for the diagnosis of hepatocellular carcinoma.     

Cytologic features of subependymal giant cell astrocytom: a review of 7 cases

OBJECTIVE: To describe the cytologic features of subependymal giant cell astrocytoma (SEGA) on smears and analyze cytomorphologic parameters that may help in reaching the diagnosis of SEGA. STUDY DESIGN: Cytologic smears of 7 cases of SEGA were reviewed and graded semi-quantitatively for 11 cytologic features: clustering, cytoplasmic fibrillary processes (fibrillarity), cellularity, small prominent nudcleoli, binucleation or multinucleation, "strap cells", spindle-shaped cells, mitoses, intranuclear inclusions, nuclear atypia and perivascular palisading/pseudorosettes. Corresponding histologic sections were also reviewed. RESULTS: The study included 5 male and 2 female patients with an average age of 8.3 years (range, 3-16) at surgery. Cytologic examination revealed loosely cohesive clusters of large cells possessing round to oval nuclei with no or minimal atypia; fine, evenly distributed chromatin; and abundant eosinophilic cytoplasm enmeshed in abundant thin, hairlike processes. Predominant features included hypercellularity, cell clustering, and fibrillarity. Binucleation or multinucleation; small, prominent nucleoli; and strap cells were often seen. Although common in histologic sections, perivascular palisading/pseudorosettes and spindled astrocytic cells were rarely noted on smears. CONCLUSION: The cytologic features of SEGA are highly characteristic and thus are of great use in supporting a diagnosis of SEGA and in excluding mimics, primarily gemistocytic astrocytoma and ependymoma.     

Cytologic findings in calcifying epithelial odontogenic tumor: a case report

BACKGROUND: Calcifying epithelial odontogenic tumor (CEOT), or Pindborg's tumor, is a rare, benign, odontogenic neoplasm first described by Pindborg in 1955. It is most commonly seen in the fourth and fifth decades of life, usually arises in the mandibular premolar-molar areas and accounts for approximately 1% of all intraosseous odontogenic tumors. This report describes the cytologic findings in a case of CEOT. CASE: A 62-year-old woman was referred to the ear, nose and throat clinic with a right maxillary mass. The fine needle aspiration (FNA) smears showed numerous calcifications; amorphous, eosinophilic material; and clusters of round epithelial cells embedded in a bloody background. The smears were diagnosed as suspicious for malignancy. Maxillectomy was done. The histologic sections were diagnosed as CEOT. CONCLUSION: FNA findings of calcifying epithelial odontogenic tumor have been described rarely. The clusters of epithelial cells with prominent nucleoli are mistaken for features of a malignant tumor.     

Bronchial cytology in pleural mesothelioma. A report of 3 positive cases, including 1 diagnosed initially on bronchial brushings

OBJECTIVE: To evaluate retrospectively the value of bronchial aspiration cytology in patients with histologically proven pleural mesothelioma, reappraising positive smears in light of conventional microscopic features and, when feasible, immunocytochemical investigations. STUDY DESIGN: In 3 cases of mesothelioma with bronchial brushings positive for malignant cells, the cytologic features were correlated with the histologic findings. RESULTS: Salient microscopic features included scant to moderate cellularity arranged in micropapillary clusters, morular aggregates with scalloped borders and isolated malignant cells. Intercellular clear spaces or windows suggesting a brush border on cell membranes were also noted. In cases with available material, immunocytochemistry was positive for keratins, epithelial membrane antigen and calretinin and negative for carcinoembryonic antigen. All the cases were histologically confirmed epithelial mesotheliomas. CONCLUSION: In rare cases, pleural mesothelioma cells are shed within the airway lumina and can be detected in bronchoscopic cytology specimens. Cytologic features seem comparable to their analogues in pleural effusions. Although no single criterion appears diagnostic, their combined documentation could ensure correct interpretation, especially if supported by a limited immunocytochemical panel.