Pap test, HPV test, and histological diagnosis of cervical
disease
All patients underwent Pap tests and HPV tests using liquid-based
cytology samples. Scraped cell samples were collected with a
Cervex-Brush (Rovers Medical Devices, Oss, Noord-Brabant, The
Netherlands) and placed in liquid-based cytology solution. Sample
collection was performed by an experienced obstetrician or gynecologist.
Pap tests were performed according to the Bethesda system by
cytotechnologists, and the results were verified by pathologists.
Abnormal Pap test results included atypical squamous cells of
undetermined significance (ASCUS), atypical squamous cells not excluding
high-grade squamous intraepithelial lesions (ASCH), low-grade squamous
intraepithelial lesions (LSIL), high-grade squamous intraepithelial
lesions (HSIL), and squamous cell carcinoma. In Japan, women with
high-risk HPV type-positive ASCUS, ASCH, and LSIL or worse undergo
colposcopy; histological examination is performed based on the
colposcopy findings. Histological diagnosis in this study was based on
the World Health Organization classification. Pap test results was
evaluated in the present study, since histology data had not been
available. Abnormal cervical Pap test results were defined as LSIL or
ASCH or worse (LSIL/ASCH+) and HSIL or worse (HSIL+). HPV genotypes were
determined using Genosearch-31 (MBL Life Science, Tokyo, Japan), which
is a novel genotyping system based on the polymerase chain reaction
reverse sequence-specific oligonucleotides Luminex® method (Luminex,
Austin, TX, USA) with HPV type-specific primer pairs (21). This system
is able to detect 31 HPV genotypes (HPV6, 11, 16, 18, 26, 31, 33, 35,
39, 42, 44, 45, 51, 52, 53, 54, 55, 56, 58, 59, 61, 62, 66, 68, 70, 71,
73, 82, 84, 89, and 90). This test was performed in a commercial
laboratory (LSI Medience, Tokyo, Japan).