Document Type: Methodological papers
Department of Pathology, Faculty of Medicine, Khon Kaen University, Thailand.
Objective: We aimed to compare the cytomorphological diagnosis in serous effusion and quality of background
between modified liquid-based cytology (modified-LBC) and CytoRich Red (CRR) preservative. Methods: We used
an experimental study design: 110 fresh serous effusions were received from 50 cases negative for malignant effusions
and 60 cases positive for malignant effusions. All fresh serous effusions were processed using both the CRR solution
and the modified-LBC preparation. Blind sample slides were interpreted for cytomorphological diagnosis and the
quality of background by 2 cytotechnologists. Result: All cases had the same diagnosis irrespective of the method.
There was no statistically significant difference in the cytological diagnosis between the CRR and modified-LBC
preparations (p>0.999). The quality of the background smear for the CRR preparation was clean (54%), moderate in
42%, and poor in 4%. By comparison, the modified-LBC preparation was clean in 46%, moderate in 47%, and poor in
7%. The difference between the quality of background smears between the two methods was not statistically significant
(p= 0.527). Conclusion: There was no statistically significant difference in the diagnosis or quality of background
between CRR and modified-LBC preparations. The serous effusion specimen prepared by modified-LBC solution was
less expensive than CRR. The modified-LBC could be an alternative preparation when commercial preparations are