Author(s): Dr. Tarak Nath Mahanta,
BACKGROUND The grade of dysplasia on cervical pap smears may be indicated by micronucleus (MN) scoring, much like cancers of oral cavity, urinary bladder and esophagus. METHODS This is a cross sectional study. MN scores of 106 subjects comprising of all major diagnostic categories included in ‘The Bethesda system, 2014 for reporting cervical pap smears’ were taken. High grade squamous intraepithelial lesion (HSIL) and invasive carcinoma (IC) were further grouped as ‘high-risk’ and the rest, ‘low-risk’ to construct Receiver Operating Characteristic (ROC) curve to seek a cut-off delineating the two classes. Analysis of variance was used to determine significance of differences in MN scoring between the various groups. RESULTS Difference of mean MN scores of HSIL (9.4) and IC (10.7) was significant from the low-risk group but not within themselves. A huge difference in MN scores between low grade squamous intraepithelial lesion and HSIL is notable. The difference of mean age was significant between high and low risk groups. ROC curve delivered a cut-off of 5.15 to distinguish between the two categories with 85.7% sensitivity, 97.2% specificity and 93.3% accuracy. CONCLUSIONS Sequential and significant increase of MN score from low to high grade dysplasia is established by current study. A cut-off of 5.15 MN score adequately detects HSIL and IC. Despite its performance, MN scoring is time-consuming, labour intensive and strenuous process, which might make it difficult to impose on laboratories and pathologists.