Modified Papanicolaou staining protocol with minimum alcohol use: a cost-cutting measure for resource-limited...

To devise a simple, cost-effective protocol for Papanicolaou (Pap) staining of cervicovaginal smears.

Five hundred coded paired cervical smears were collected from women as part of routine cervical cancer screening. One set of smears was stained by conventional Pap staining protocol (CP) and the other by a modified protocol (MP) in which alcohol was replaced by 1% acetic acid in all the steps except during fixation and prior to mounting; in addition, one alcohol-based counterstain, OG, was omitted. The smears were examined blindly by the pathologists and then decoded. Each pair of smears was compared and the two protocols were analysed for staining quality and diagnoses by McNemar and chi-square tests.

The staining quality in the MP was satisfactory. The nuclear and cytoplasmic features were comparable to the CP. Cytoplasmic transparency was maintained in the MP and the differential staining of blue/green and pink was acceptable to the pathologists and technicians. The diagnoses agreed in all cases and there was no compromise in interpreting the smears. With MP it took only 3-4 minutes to stain a batch of 50 slides. in contrast to the 20 minutes taken by CP. The MP used almost one-seventh of the amount of alcohol compared with CP, which translated into a significant cost reduction per smear.

The improvised Pap staining protocol with minimum alcohol use is a simple, cost-effective and technician-friendly procedure that can be easily adopted in high-volume, resource-limited laboratories for mass cervical cancer screening.