Cytomorphologic analysis and histological correlation of high-grade squamous intraepithelial lesions in...

Atrophy-related epithelial changes often pose a diagnostic difficulty during the interpretation of postmenopausal smears. The objectives of this study are to identify the cytomorphologic features of HSIL, in Pap smears of postmenopausal Pap women, and to investigate the possible criteria that could lead to an inaccurate interpretation and false-positive results. Forty Pap smears that were reported as HSIL in postmenopausal women were reviewed. Follow-up cervical biopsies were available on all cases, of which 6 cases were immunostained for MIB-1 and P16. The following cytomorphologic features were evaluated: smear background, degree of cellularity, cellular arrangement, nuclear size, nuclear membrane irregularity, nuclear/cytoplasmic ratio, hyperchromasia, and chromatin pattern. Significant histological abnormalities were present in 35 out of 40 cases. Of those, 22 (55%) cases had high-grade cervical intraepithelial neoplasia (CIN2 or CIN3), 10 (25%) had CIN-1, 5 (12.5%) had reactive changes in the biopsy, and 3 cases had invasive squamous cell carcinoma. The cytomorphologic features that favored HSIL (P < 0.05) included: increased number of abnormal cells, nuclear membrane irregularities, cellular arrangement, and high nuclear/cytoplasmic ratio. Granular background, nuclear size, hyperchromasia, and abnormal chromatin pattern can be associated with reactive and atrophic changes. Our study showed that cytomorphological features favoring HSIL in postmenopausal smears include increased number of abnormal single cells with high nuclear/cytoplasmic ratio and irregular nuclear membrane. Granular background, nuclear enlargement, abnormal chromatin pattern, and hyperchromasia can be seen in reactive changes, and may lead to inaccurate interpretation.