Bile cytology diagnosis in challenging cases: Validation of diagnostic bile cytology criteria and extensive study for immunocytochemical markers.

BACKGROUND: Bile cytology is useful in diagnosing biliary tract lesions, albeit often challenging due to equivocal findings. To achieve better diagnoses for clinical decisions, we conducted cytomorphological and immunocytochemical studies of bile cytology cases. MATERIALS AND METHODS: We re-evaluated 40 bile cytology cases with initial equivocal diagnoses, taken from the cytology records of Jichi Medical University Hospital, including 1778 bile cytology specimens. First, we assessed the cases by the diagnostic bile cytology criteria of the Japanese Society of Clinical Cytology. Second, we searched for useful immunocytochemical markers by extensive immunohistochemical analyses using tissue microarray for 10 antibodies: S100P, IMP3, GLUT1, p53, S100A4, Mapsin, MUC17, CD10, MDM2, and SMAD4. Microarrays were from 257 extrahepatic bile duct carcinoma cases. To elucidate the utility of immunocytochemistry, we applied selected markers to immunocytochemical evaluation of the equivocal cases after cell transfer. RESULTS: The criteria indicated a sensitivity 60%, specificity 87%, and accuracy 70%. Irregularly overlapping (88%), arranged (96%), and shaped (76%) nuclei were more common in malignant cases, while enlarged nuclei were more frequent in benign cases (67% vs. 28%). We applied S100P and IMP3, which showed higher accuracy (88% and 77%) in tissue microarray, to immunocytochemistry. The sensitivity of S100P and IMP3 were 69% and 70%, respectively. The specificity of S100P and IMP3 were 50% and 100%, respectively. CONCLUSION: The criteria showed a certain effectiveness even in challenging cases, and some pitfalls associated with reactive changes of benign cells. Although comprehensive diagnosis including cytomorphology seems preferable, S100P and IMP3 are promising immunocytochemical markers.

Cytological detection of metastatic chordoma cells in pleural effusions: A case report.

Cytological detection of chordoma cells in the serosal cavity is challenging because of its rare presentation. Herein, we report a case of chordoma showing malignant pleural effusion accompanied by pleuropulmonary metastases in a 68-year-old woman. Cytological analysis was performed using pleural fluid obtained following thoracentesis. Conventional cytological staining demonstrated few clusters of large, atypical cells characterized by epithelial cell-like connectivity and rich cytoplasm with foamy and/or multivacuolar changes. The nuclei of these atypical cells were large and either round or oval with no conspicuous irregularities in the nuclear membrane. Periodic acid-Schiff staining of these atypical cells revealed fine granules in the cytoplasm. Giemsa staining showed foamy and/or multivacuolar cytoplasm in these cells, with metachromatic mucoid stroma in the surroundings. Immunocytochemistry analysis using cellblock showed these cells to be positive for broad cytokeratins, epithelial membrane antigen, S100 protein, vimentin, and Brachyury. To the best of our knowledge, this is the first case report in which chordoma cells were cytologically detected in pleural effusions. Our findings also suggest that conventional cytology combined with cellblock immunocytochemistry can increase the accuracy of chordoma cell detection in the serosal cavity.