Koji Teruya

Predictive Value of Various Atypical Cells for the Detection of Human Papillomavirus in Cervical Smears

It is thought that numerous genotypes of human papillomavirus (HPV) are associated with various atypical cells, such as multinucleated cells, koilocytes, binucleated cells, parakeratotic cells, and giant cells, in the cervix. We previously showed the specificity of HPV genotypes for koilocytes and multinucleated cells. Therefore, in this study, we analyzed the association among HPV genotypes and binucleated cells, parakeratotic cells, and giant cells in Papanicolaou (Pap) smears. We detected HPV genotypes and atypical cells in 651 cases of liquid-based cytology with an abnormal Pap smear. The HPV genotypes associated with atypical cells were evaluated using stepwise logistic regression with backward elimination and a likelihood ratio test for model construction. Polymerase chain reaction was used to determine the HPV genotypes in whole liquid-based cytology samples and microdissected cell samples from Pap smear slides. Binucleated cells were significantly associated with HPV genotype 42. Moreover, parakeratotic cells were significantly associated with certain HPV genotypes, such as HPV40. However, it was difficult to detect specific HPV genotypes by the manual microdissection-polymerase chain reaction method despite the presence of binucleated cells and parakeratotic cells. Thus, the presence of binucleated cells, parakeratotic cells, and giant cells in Pap smears may not be predictive of cervical lesions above low-grade squamous intraepithelial lesions or infection with highly carcinogenic HPV genotypes.

Effects of Menstrual Cycle on Various Morphologies of High-Grade Squamous Intraepithelial Lesions in SurePath™ Liquid-Based Cervical Cytology

<b><i>Introduction:</i></b> The morphology of high-grade squamous intraepithelial lesion (HSIL) on Papanicolaou (Pap) smears widely varied, including syncytial aggregates, sheets, and scattered single cells, and no particular cellular pattern is consistently observed. Therefore, this study aimed to determine whether the menstrual cycle affects the cellular pattern of HSILs, an effort to avoid false negatives due to the oversight of scattered small single HSIL cells in the cytological triage of human papillomavirus-positive women. <b><i>Methods:</i></b> A total of 147 HSIL samples of liquid-based cytology (LBC) in patients with cervical intraepithelial neoplasia grade 2 or 3 were obtained, and then, the relationship between cellular patterns, such as single-cell-like and syncytial aggregates, and menstrual cycles classified into six phases was analyzed. If a syncytial aggregate was present, the number of cells constituting the aggregate was visually counted under the microscope. <b><i>Results:</i></b> HSILs in scattered single cells and small sheets of <6 on LBC samples accounted for 43% (23/54) during the late proliferative phase of the menstrual cycle. A moderately strong statistically significant association was observed between cellular patterns and menstrual cycles (χ<sup>2</sup> [3] = 9.423, <i>p</i> < 0.05) (Cramer’s V = 0.253). The value of adjusted residuals showed a statistically significant increased proportion of single-cell-like patterns during the late proliferative phase (<i>p</i> < 0.01). <b><i>Conclusions:</i></b> The present study demonstrated that HSIL cells in Pap smears in the late proliferation phase have a high frequency of single-cell-like patterns. In human papillomavirus-positive Pap smears with a clean background and predominantly superficial cells, careful microscopic observation by targeting single HSIL cells can potentially reduce false negatives.

Preferential Tissue Sites of Different Cancer-Risk Groups of Human Papillomaviruses

The oncogenic potential of human papillomavirus (HPV) may be used to determine the tissue tropism of each HPV type. Cervical cancer develops in the squamo-columar junction of the cervices, and most lesions are induced by high-risk (HR) HPV types. This suggests that HR types preferentially infect the cervix, whereas the preferential infection site for low-risk (LR) types is not well defined. The determination of HPV tropism when using cytology samples can be uncertain since it is difficult to avoid contamination of cell samples between the cervix and the vagina. Herein, cell samples were carefully collected by independently scraping the cervix and vagina, after which the HPV types were determined. HPV tissue tropism was determined by considering what HPV types were positive at only one of the sites (the cervix or the vagina) as the viruses that preferentially infected that site. This method revealed that all LR types were only identified in vaginal samples, whereas 87% of HR types were identified in cervical sites. Thus, LR types may preferentially infect the vagina, whereas HR types infect the cervix. These findings suggest that preferential tissue tropism of certain HPV types is a probable factor for malignant progression.