Micronucleus in atypical squamous cell of undetermined significance.

The aim of this study was to explore the role of micronucleus (MN) scoring in distinguishing the smears of atypical squamous cell of undetermined significance (ASCUS) with reactive outcome versus ASCUS with cervical intraepithelial lesions (CIN) outcome. In this retrospective study, there were 53 cases of ASCUS diagnosed on cervical cytology smear and of which 30 cases showed reactive changes (group 1) and 23 cases showed CIN (group 2) on follow up histology. MN score of group 1 was compared with group 2 in conventional Papanicolaou's stained smear. The micronucleated cell per 1,000 epithelial cells in oil immersion magnification (100× objective) was counted by two observers and expressed as MN score. The data were compared in the two groups. The mean MN score was 2.8667 ± 2.20866 in group 1 and 8.3478 ± 6.44987 in group 2 cases. The Student's t-test showed significant difference of MN score in group 2 compared to group 1 (P < 0.0001). MN score may be helpful in identifying the true CIN cases that are mislabeled as ASCUS on cervical smear. In future, MN score can be used as an additional biomarker in cervical cancer screening.