Background: The diagnostic performance of cytology was compared with the frozen results and its usability was evaluated as a rapid diagnosis method in intraoperative thoracic surgery in a single institution (Istanbul, Turkey).Methods: All 197 subsequent patient specimens (cases) from 158 patients who were sent to our department from the thoracic surgery clinic for an intraoperative diagnosis request between the years 2016 and 2021 were evaluated. Obtained results from frozen and cytology were compared with final paraffin section diagnoses. Lesions were grouped into three different groups as nonneoplastic, benign, and malignant neoplasms.Results: Diagnostic accuracy values of cytology and frozen sections in intraoperative consultation were 98.8% and 99.4%, respectively. Sensitivity values of cytology and frozen sections in intraoperative consultation were 96.3% and 98.7%, respectively. Specificity values of cytology and frozen sections in intraoperative consultation were 100% and 100%, respectively. Negative predictive values of cytology and frozen sections in intraoperative consultation were 96.7% and 98.9%, respectively. Positive predictive values of cytology and frozen sections in intraoperative consultation were 100% and 100%, respectively. Kappa statistics between cytology and frozen revealed a very high interrater reliability (Cohen's Kappa value: 0.911; p = .001; p < .01). The difficulty in distinguishing primary and metastatic carcinoma, which is mostly undecided in frozen sections and the definitive diagnosis is left to paraffin sections, seems also be a problem in the cytological examination.Conclusions: Cytological diagnosis can be used in the evaluation of small biopsy specimens that require tissue preservation in intraoperative consultation, especially for immunohistochemical and advanced genetic studies.

Background Several clinical groups consider cytological assessment under EBUS (Endobronchial Ultrasonography)‐ROSE (Rapid Onsite Evaluation) as the golden standard for diagnosis and staging of intrathoracic lesions. On the other hand, some investigators proposed that EBUS‐TBNA (Transbronchial Needle Aspiration) has considerably high false‐negative rates for diagnosis. In this study, we analyzed our patient cohort (n = 152) with intrathoracic lesions and suspected malignancies evaluated by EBUS‐ROSE. Our specific aims were: (i) to determine whether EBUS‐ROSE could provide sufficient pathologic material for diagnosis and staging; (ii) to determine the fidelity of EBUS‐ROSE‐guided initial diagnoses in comparison to paraffin block diagnoses; (iii) to evaluate whether anatomical localization of sampled lymph nodes associate with material adequacy and final diagnoses. Methods NCSS (Number Cruncher Statistical System) 2020 Statistical Software (Utah, USA) was used for statistical analysis. Results In EBUS‐ROSE cytological assessment, material adequacy was determined in 50,7% (n = 77) of the cases. Considering the paraffin block pathology as the golden standart, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy rates of EBUS‐ROSE were 90,2%, 93,1%, 94,8%, 87,1%, and 91,4%, respectively. There was no statistically significant difference between the final pathology and EBUS cytology results (p > .05) with a non‐random Kappa agreement rate as 82.9%. There were differences in material adequacy and diagnoses according to the localization of sampled lymph node stations. Conclusions EBUS‐ROSE is efficient to decide for the adequacy of the pathological specimen and provides diagnoses with reliable fidelity.