Neuza Kasumi Shirata

Immunocytochemical Expression of p16ink4a and Ki-67 in Cytologically Negative and Equivocal Pap Smears Positive for Oncogenic Human Papillomavirus

This study was designed to analyze the cross-sectional comparison of the p16INK4A and Ki-67 immunocytochemical expression in negative and equivocal (atypical squamous cells of undetermined significance (ASC-US)) liquid-based cytology (LBC) samples testing positive for high-risk human papillomavirus (HPV) types with HC2 assay or polymerase-chain reaction (PCR). A series of 199 consecutive LBC specimens derived from the same number of women participating in the ongoing Latin American Screening Study at Leonor Mendes de Barros Hospital, São Paulo, were analyzed using immunocytochemistry for expression of p16INK4A and Ki-67 in negative and equivocal LBC samples testing positive for high-risk HPV types with hybrid capture II test (HC2) or PCR. All patients with at least one test positive (cytology, PCR, and/or HC2) were followed each 6 months for 3 years. The follow-up procedure consisted of visual examination, colposcopic inspection, cytology, and HC2 assay. Among the negative cytologic samples, 101 were HPV-positive and 55 HPV-negative. Of the HPV-positive group, 59 of 101 cases (58.4%) were positive for both p16 and Ki67 immunostaining, and 17 of 101 (16.8%) were negative for both. The proportion of Ki-67-positivity increased almost in parallel with the increasing grade of p16-positivity (p = 0.0001 for linear trend). In the HPV-negative group, both markers were negative in 41 of 55 cases (74.5%), and no statistical relationship was observed between the two markers (Pearson, p = 0.595). HPV-positive ASC-US samples demonstrated a simultaneous positive immunoreaction for p16 and Ki67 in 11 of 16 cases (68.7%), whereas 3 (18.7%) were concurrently negative. The relationship between the two markers was of borderline significance (Pearson, p = 0.053), but no linear relationship was found between the graded p16 and Ki-67 expression (p = 0.065 for linear trend). In the HPV-negative ASC-US group, there was no statistical association between the graded p16 and Ki-67 positivity (Pearson, p = 0.281). After 36 months of follow-up of the ASC-US patients, 6 women still displayed ASC-US smear, of which 4 of 6 were HPV-positive and expressed both p16 and Ki-67 markers. Two of 43 ASC-US smears had high-grade squamous intraepithelial lesions diagnosed (4.6%), and 1 had low-grade squamous intraepithelial lesion (2.3%). All of those were positive for HPV, p16 and Ki-67. Patients with ASC-US diagnosis and positive high-risk HPV status and positive for p16INK4A Ki67 should be carefully observed to exclude occurrence of a squamous intraepithelial lesion. The combination of these two markers can be a useful implement for management of women with equivocal cytology.

Cervical intraepithelial neoplasia in adolescents: study of cytological findings between 1987 and 1995 in São Paulo State-Brazil.

Abstract. The purpose of the present study was to ascertain the frequency of Pap smears abnormalities (SIL/carcinoma) in two populations in the State of S. Paulo (Brazil) who were screened for cervical cancer during the last nine years: adolescents (up to the age of 21) and adults (over 21). Statistical analysis showed a tendency to linear increase in frequency of abnormal Pap smears in both groups (adolescent: slope = 0.118±0.56; adult: slope = 0.079±0.021), being greater in the adolescent group (slope 0.039±0.038) than in the adult group. Between 1987 and 1995 the prevalence of abnormal smears tripled in the adult group (from 0.37 to 1.18) and almost quadruplicated in the adolescent group (from 0.64 to 2.10). Low grade squamous intraepithelial lesions (SIL) were the most frequent findings in cervical cytology in both groups: 92.3% in the adolescent group and 69.8% in the adult group. Few cases of high grade squamous intrapeithelial lesions (HSIL) (7.7%) and no cases of carcinoma were found in adolescent population. We suggested that sexually active adolescents should be included in cervical screening programs.

Papillomavirus in cervicovaginal smears of women infected with human immunodefficiency virus

It has been described that women infected with the human immunodeficiency virus (HIV) present more frequent cytological abnormalities in cervicovaginal smears, generally related to infection by human papillomavirus (HPV). The present work is a study of cervicovaginal smears of 147 HIV-seropositive women submitted to routine gynecological examinations. The smears were stained by the Papanicolaou method. Cytopathic effects of HPV were found in 38 (25.8%) cases. Nuclear atypias of cervical intraepithelial neoplasia (CIN) were evident in 36 (24.5%) of these cases: 27 (18.4%), CIN I; 6 (4.0%), CIN II and 3 (2.0%) CIN III. Also 2 (1.4%) invasive carcinomas and one (0.7%) endocervical dysplasia were found. Other agents observed were: Candida sp, 19 (12.9%) cases, Gardnerella vaginalis, 19 (12.9%), Trichomonas vaginalis, 13 (8.4%), Chlamydia trachomatis 5 (3.4%), Mobiluncus sp 2 (1.4%) and Herpes simplex virus 1 (0.7%). This study emphasizes the high frequency of HPV/CIN cervicovaginal abnormalities in HIV-seropositive in our population. It is possible that immunological factors and sexual promiscuity are involved in this phenomenon.

Image analysis of nuclear/cytoplasmic ratio in cervical smears to discriminate three grades of cervical intraepithelial neoplasia.

OBJECTIVE To suggest which system of cytologic classification (Bethesda System or World Health Organization [WHO]) of cervical lesions is more adequate for the Public Health Service of São Paulo State, Brazil, based on morphometric study with the Jandel Videoanalysis (JAVA) System. STUDY DESIGN The study comprised groups of typical smears: cervical intraepithelial neoplasia (CIN 1) separated into two subgroups: cytopathic effects of human papillomavirus associated or not with dyskaryosis, CIN 2 and CIN 3. The JAVA system of image analysis was used to determine the nuclear/cytoplasmic (N/C) ratio in abnormal cells from each group. RESULTS Significant differences were detected between the three grades of CIN and between the two subgroups of CIN 1. CONCLUSION Although image analysis is not applicable to large-scale population screening of cervical smears, its use in the present study favored the three-grade cytologic classification (WHO). In addition, the three-grade classification offers the clinician more options for treatment. Considering the clinical-laboratory characteristics of our public health service, the three-grade classification is more adequate.

DNA measurements after radiation-induced tissue structure of thyroid gland of rats

INTRODUCTION: Thyroid gland exposures to radiation induce nuclear chromosomal alteration. Objective: To evaluate the DNA content of thyroid gland submitted to radiation. MATERIALS AND METHODS: We radiated 75 rats while 25 were not radiated to be used as control group. Exposure was conducted by the use of Cobalt-60 radioactive source in the right anterior cervical region in a field of 3-30cm, comprising the second and the sixth tracheal rings with 600-centigray (cGY) doses. The DNA content (ploidy) was obtained with Feulgen-thionin stain and was quantified with CAS 200 quantitative measurement equipment. RESULTS: Diploid pattern was obtained in 88 cases (95.7%), independently of time of exposure: on the other hand, aneuploidy was observed in four cases (4.3%) only in the group sacrificed to the 33 days. Eight cases were excluded due to technical reasons. CONCLUSION: The early aneuploid pattern found in our study certainly corroborated that radiation affects thyroid gland with important consequences in terms of disorders.