Background: In current medical diagnostic processes, pathological examination, including surgicopathological study, is the gold standard, especially for neoplasia or oncology. Recently, there has been a developmental trend towards minimally-or less-invasive investigation techniques, and one of these modalities is cytological (or cytopathological) examination. This study aimed to examine the level of agreement between the conventional and less invasive methods, in terms of their usefulness and limitations, in order to determine the most appropriate diagnostic method for individual cases in the future. The selection of respiratory system specimens for this study was made because of the large number of cytological tests that are available, and we wanted to be able to check the results of each test with surgicopathological ones. There are various tests, such as bronchial washing (BW), bronchoalveolar lavage (BAL), pleural effusion (PE) and transbronchial needle aspiration (TBNA). In surgical pathology, the specimen type used is a transbronchial lung biopsy (TBLB). This study was conducted in Rajavithi Hospital, which is a super tertiary hospital.

Objective: To study the agreement between cytological and surgicopathological diagnoses in patients with respiratory disorders in Rajavithi Hospital from 2015 to 2017.

Materials and Methods: Diagnoses of respiratory specimens of Rajavithi Hospital from 2015 to 2017, obtained from both cytology and surgical pathology, were retrospectively collected and analyzed.

Results: In surgicopathological diagnoses, 53 (46.1%), 9 (7.8%) and 53 (46.1%) were in the malignancy, borderline and benign categories respectively compared with 28 (24.3%), 18 (15.7%) and 69 (60.0%), respectively from cytological tests. The overall concordance between the cytological and surgicopathological diagnoses in benignity was 65.2% and in malignancy 82.1%.

Conclusion: The agreement between the cytological and surgicopathological diagnoses in respiratory specimens in Rajavithi Hospital from 2015 to 2017 was statistically significant at a low level. The agreement was higher in some subtypes of cytological diagnoses than in others, with 84.61%, 83.72% and 68.29% from TBNA, PE and BAL, respectively. In terms of validity of diagnosis, cytology had other benefits over surgical pathology which need to be considered in each clinical situation. However, both methods should be used to complement each other in order to reach more definite diagnoses.

Keywords: Agreement, Correlation, Rajavithi Hospital, RJVH, Cytology, Cytopathology, Histopathology, Pathology, Surgical pathology