Hyperchromatic crowed groups (HCGs) are defined as three-dimensional aggregates of crowded cells with hyperchromatic nuclei, and are frequently encountered in cervicovaginal liquid-based cytology (LBC). Here, we aimed to examine the prevalence of HCGs in cervicovaginal LBC and the cytomorphological characteristics of various epithelial cell clusters presenting as HCGs.
HCGs was observed in 34.4% of the routine cohort and were significantly more frequent in the epithelial cell abnormality category compared to the non-neoplastic category (p=.003). The majority of HCGs represented atrophy (70%). Of the 69 histologically confirmed H-ECA cases, all contained HCGs. The majority of cases were HSIL (62%), followed by SCC (16%). Individually scattered neoplastic cells outside the HCGs were significantly more frequent in SCCs compared to glandular neoplasia (p=.002). Despite the obscuring thick nature of the HCGs, examining the edges and the different focal planes of the HCGs and the background were helpful in defining the nature of the HCGs.
CONCLUSIONS:
HCGs were frequently observed in cervicovaginal LBC and were mostly non-neoplastic; however, neoplastic HCGs were mostly high-grade lesions. Being aware of the cytomorphological features of different HCGs is important in order to avoid potential false-negative cytology interpretation.