Comparison of specimen adequacy and smear quality in oral smears prepared by manual liquid-based cytology and conventional methods

BACKGROUND: Liquid-based cytology (LBC), recommended in the mass screening of potentially malignant cervical and oral lesions, suffers from high cost owing to the use of expensive automated devices and materials. Considering the need for cost-effective LBC techniques, we evaluated the efficacy of an inexpensive manual LBC (MLBC) technique against conventional cytological technique in terms of specimen adequacy and smear quality of oral smears. MATERIALS AND METHODS: Cytological samples were collected from 21 patients using a cytobrush device. After preparation of a conventional smear, the brush containing the remaining sample was immersed in the preservative vial. The preserved material was processed by an MLBC technique and subsequently, direct smears were made from the prepared cell button. Both conventional and MLBC smears were stained by routine Papanicolaou technique and evaluated by an independent observer for the thickness of the smear, cellular distribution, resolution/clarity of cells, cellular staining characteristics and the presence of unsatisfactory background/artifacts. Each parameter was graded as satisfactory; or satisfactory, but limited; or unsatisfactory. Chi-square test was used to compare the values obtained (significance set at P ≤ 0.05). RESULTS: MLBC technique produced a significant number of satisfactory smears with regard to cell distribution, clarity/resolution, staining characteristics and background/artifacts compared to conventional methods. CONCLUSIONS: MLBC is a cost-effective cytological technique that may produce oral smears with excellent cytomorphology and longer storage life.