Assessment of precancerous lesions of the uterine cervix for evidence of human papillomavirus infection: a histological and immunohistochemical study

The use of conization to identify and treat severe lesions among prediagnosed CIN1 and 2 patients in Japan

Objective

To evaluate the clinical efficiency of identifying patients with suspicious severe lesions by conization among prediagnosed cervical intraepithelial neoplasia (CIN) 1 and 2 patients in Japan.

Methods

The data in a Japanese nation-wide registry for cervical cancer (2009 and 2011) was collected to analyze the clinical efficacy of pre- and postdiagnosis for 13,215 Japanese women who underwent treatment by conization. Their preoperative and postoperative histologic findings and clinical outcomes were evaluated using standard statistical procedures including clinical and demographic characteristics.

Results

Almost half of 1,536 women who were treated by conization after the prediagnosis of CIN1 and 2 because the lesions showed no evidence of natural regression actually contained CIN1–2 (45.0%), CIN3 (47%), or invasive cancer (2.7%) in their cervical tissue. They underwent conization either for therapeutic (treatment) (78.5%) or diagnostic (21.5%) reasons. Invasive disease was diagnosed postoperatively more often in diagnostic cases (6.1%) than in therapeutic cases (2.8%). All the patients survived their diagnostic and therapeutic conization after approximately 30 months of follow up.

Conclusion

Our study shows that the continuous observation of the prediagnosed CIN1 and 2 cases by the combination of cytology, colposcopy and histology in Japan has worked successfully to identify severe lesions by using conization as well in the process.

Detection of papillomaviral-like DNA sequences in premalignant and malignant perineal lesions of sheep

Small hyperkeratotic and ulcerated lesions and clinical cancers were isolated from the perineal region of sheep and examined for evidence of papillomavirus infection by various criteria including gross morphology, histology, immunohistochemistry and DNA hybridisation. No specific diagnostic features of papillomaviral infection by immunohistochemistry were found, although some lesions showed gross morphological and histological features similar to papillomaviral effect in other species. DNA hybridisation analysis, using human papillomaviral type 11, 13, 16 and 18 DNA probes under conditions of reduced stringency (Tm-40 degrees C), detected homologous sequences in two thirds of the biopsies examined. These homologous sequences occurred in benign hyperkeratosis as well as invasive squamous cell carcinomas but were much more frequently isolated from carcinomas. This finding suggests that a papillomavirus is associated with the development of squamous cell carcinomas of the perineum of sheep.

Glutathione S-transferase (placental) as a marker of transformation in the human cervix uteri: an immunohistochemical study

Using an indirect immunohistochemical technique on paraffin sections, employing a polyclonal antibody to the acidic (placental) form of glutathione-S-transferase (GST), we have evaluated cytoplasmic and nuclear staining in a series of 67 cervical biopsies including normal non neoplastic tissue, immature squamous metaplasia, all grades of cervical intraepithelial neoplasia (CIN) and invasive carcinomas of keratinising and non-keratinising types. No differences in cytoplasmic staining between the varied lesions studied were seen. However, there were marked differences in nuclear staining. While normal non-neoplastic stratified squamous epithelium showed weak staining of the lower one-third of the epithelium only, in immature squamous metaplasia and in all grades of CIN there was intense nuclear staining in all layers of the epithelium. Invasive carcinomas showed generally less intense nuclear staining than CIN lesions. Endocervical cell nuclei also showed intense nuclear staining. These findings indicate that GST is of limited use as a marker of transformation in the human cervix uteri.

Human papillomaviruses: are we ready to type?

The issue of determining which human papillomavirus (HPV) is present in a clinical specimen (typing specimens for HPVs) is receiving attention because HPVs cause condyloma acuminata and are associated with the continuum of disease which ranges from dysplasia to invasive genital cancer. Morphological inspection of precancerous lesions is not sufficient to determine which lesions will progress and which will not. A number of research tools based primarily on deoxyribonucleic acid hybridization have been developed. These permit identification and typing of HPV in genital tract scrapings or biopsies. Some HPV types (e.g., HPV-16 and HPV-18) have been identified in high-grade dysplasias and carcinomas more commonly than other types (e.g., HPV-6) and have been designated "high risk" types for cervical cancer. Thus, the question arises whether HPV typing would improve patient management by providing increased sensitivity for detection of patients at risk or by providing a prognostic indicator. In this review, the available typing methods are reviewed from the standpoint of their sensitivity, specificity, and ease of application to large-scale screening programs. Data implicating HPVs in the genesis of genital tract cancers are reviewed, as is the association of specific HPV types with specific outcomes. We conclude that there is currently no simple, inexpensive assay for HPV types, although such assays may be developed in the future. Analysis of the typing data indicates that, while HPV types can be designated high risk and low risk, these designations are not absolute and thus the low-risk group should not be ignored. In addition, interpretation of the data is complicated by finding high-risk types in individuals with no indication of disease. Insufficient data exist to indicate whether knowledge of the presence of a given HPV type is a better prognostic indicator than cytological or histological results. Thus, more research is needed before it can be determined whether typing information will augment the method currently in use for deciding treatment regimen and whether it warrants widespread use.

Human papillomavirus coinfections of the vulva and uterine cervix

DNA filter in situ hybridisation (FISH) was used to determine the presence of human papillomavirus (HPV) genotypes 6/11, 16/18, and 31/33 in cell scrapes of the cervix and vulva of 128 women who had precancerous lesions and/or HPV infection of the cervix diagnosed by cytology, colposcopy, and histology. HPV-DNA was found in 87 (68%) vulval and 95 (74%) cervical cell scrapes, and in both the vulval and cervical scrapes of 73 (57%) women, but not in either the vulva or the cervix of 19 women (15%). Of the HPV-DNA-positive smears, the prevalence of the HPV types was 61% HPV 16/18, 14% HPV 6/11, 3% HPV 31/33, and 22% HPV 6/11 and 16/18. By contrast, HPV-DNA was not detected in the cervical smears of a control group of 35 women who were assessed to be free of cervical abnormalities by colposcopy and cytology. The epithelial response of the vulva and the cervix to application of 5% acetic acid was assessed by colposcopy and the results correlated with the presence of HPV genotypes. A possible or definite disorder of the cervix and vulva was detected by colposcopy in 95 (74%) and 96 (75%) of the 128 cases, respectively. The colposcopic assessment of the vulva was inconclusive in ten cases (8%), and only eight women (6%) were found to be free of both a vulval and cervical disorder. This study shows subclinical papillomavirus infections of the vulva frequently coexist with HPV infections and precancerous lesions of the cervix.(ABSTRACT TRUNCATED AT 250 WORDS)

Detection of human papillomavirus DNA in cell scrapes and formalin-fixed, paraffin-embedded tissue of the uterine cervix by filter in situ hybridisation

Filter in situ hybridisation (FISH) was used to detect the presence of DNA of human papillomavirus (HPV) types 6/11 or 16/18 in cell scrapes (CYTOFISH) and formalin-fixed, paraffin-embedded biopsies (HISTOFISH) taken from the uterine cervices of 19 women. Paraffin tissue sections collected for HISTOFISH were either digested with pepsin or lysed with alkali/Triton X-100. The digest or lysate of the tissue sections and cell scrapes were applied to nylon or nitrocellulose membranes for nucleic acid hybridisation using 32P-labeled HPV-DNA probes. CYTOFISH and HISTOFISH were compared directly by taking samples for each method from the cervices of the same women. Of 19 women examined by colposcopy, cytology, and histology, eight were assessed as normal and 11 had evidence of a cervical disorder and/or the presence of HPV infection. Whereas no HPV-DNA was detected in the normal cases, the presence of HPV-DNAs was detected by both CYTOFISH and HISTOFISH in 11 cases with histological evidence of HPV infection and/or dysplasia. In these HPV positive cases, eight contained HPV 16/18, two HPV 6/11, and one a mixed infection of HPV 6/11/16/18. The high correlation between the results of CYTOFISH and HISTOFISH shows that formalin-fixed, paraffin-embedded cervical biopsies are suitable specimens for the detection and typing of HPV-DNA by FISH. Both CYTOFISH and HISTOFISH should facilitate studies on the prevalence and distribution of HPVs and their association with neoplasia.

Detection of human papillomavirus capsid antigens in various squamous epithelial lesions using antibodies directed against the L1 and L2 open reading frames

HPV6 and HPV16 infect the squamous epithelium of the genital tract and are thought to be involved in the pathogenesis of benign and malignant lesions. HPV6 is primarily found in benign condylomas whereas HPV16 is present in dysplasias and in invasive squamous cell carcinomas. To examine the expression of the major and minor capsid proteins in these lesions polyclonal antisera directed against bacterially derived fusion proteins harboring different restriction fragments of the L1 and L2 ORFs of HPV6b and HPV16 were generated. L1 ORF-specific antisera were not type-specific and detected the major capsid antigen in lesions infected with related HPV types. Anti-L2 ORF antisera could distinguish among HPV1, HPV6, and HPV16 when the fusion protein used as the immunogen did not harbor the amino-terminus of the L2 ORF. The anti-L1 ORF antisera were employed to detect the major capsid protein in various lesions by immunohistochemical staining. Lesions harboring HPV16 were positive in a high percentage of cervical intraepithelial neoplasia I-II (87%), and less frequently in carcinomas in situ (29%) or invasive carcinomas (17%). In all cases capsid antigen expression was restricted to cells showing some differentiation at the surface or periphery of the lesion.

Cytokeratins in cervical dysplasia and neoplasia: a comparative study of immunohistochemical staining using monoclonal antibodies NCL-5D3, CAM 5.2, and PKK1

The expression of low molecular weight cytokeratins (normally expressed only in simple epithelia) in intraepithelial neoplasia of grade CIN III or greater in cervical biopsies has recently been described by Bobrow et al. Our study of 127 cases confirms this finding and in addition we compare the use of three monoclonal antibodies, namely NCL-5D3, CAM 5.2, and PKK1, in demonstrating the phenomenon. Both NCL-5D3 and CAM 5.2 give consistently negative results for non-neoplastic stratified squamous epithelium, as well as CIN I and CIN II lesions, whilst staining about 30 per cent of CIN III biopsies and most carcinomas. PKK1, on the other hand, stained 50 per cent of non-neoplastic epithelia and thus did not serve as a marker of severe dysplasia. The possible implications of these observations are discussed.

Detection of DNA of human papillomavirus types 6/11 and 16/18 in cell scrapings of the uterine cervix by filter in situ hybridisation. Correlation with cytology, colposcopy and histology

The application of filter in situ hybridisation (FISH) to detect the presence of the DNA of human papillomavirus genotypes 6/11 and/or 16/18 in cell scrapings of the uterine cervix of 248 women in Western Australia is described. The results obtained by FISH are related to cervical dysplasia as assessed by cytology, colposcopy and histology. The detection of HPV infection was more sensitive and specific by FISH than by either histological/cytological evidence of an HPV cytopathic effect (koilocytosis) or immunohistochemical staining for HPV capsid antigen using antiserum against genus specific antigen of the bovine papillomavirus. Viral DNA was detected by FISH in 65% of women with atypical cytology and of the HPV positive cases, 68% were HPV 16/18, 22% HPV 6/11 and 10% of mixed types. HPV-DNA was detected in the cervical smears of 16 women who also had HPV capsid antigen (HPV-Ag) in their cervical biopsies; HPV 6/11 was found in 4 cases and HPV 16/18 in 12 cases. The relative frequency of the HPV-Ag positive cases decreased markedly from 44% to 4% with an increase in the severity of cervical dysplasia. By comparison, the percentage of HPV-DNA positive cases remained relatively constant between 70% and 80% for all 3 categories of dysplasia. Of these, the percentage of HPV 6/11 positives decreased slightly with an increase in the severity of dysplasia as assessed by either cytology or histology, whereas the percentage of HPV 16/18 positive cases was relatively constant. HPV-DNA was found in cervical smears of 11 of 48 (23%) women who were diagnosed colposcopically to have atypical transformation zone of the cervix. In 138 women with an atypical transformation zone, 96 (70%) were found to have HPV-DNA with HPV 16/18 contributing to 83% of the HPV positive cases. All four genotypes of HPV were found to be associated with the colposcopic morphology of mosaicism (26 cases) but only HPV 16/18 was found in 12 HPV-DNA positive cases associated colposcopically with punctation and an atypical transformation zone. The detection and typing of HPV-DNA in cell scrapings by FISH is a relatively fast and non-invasive procedure which complements cytology, colposcopy and histology and should be useful in further studies of the natural history of different HPV infections and their role in cervical cancer.

DNA sequences of human papillomavirus types 11, 16 or 18 in invasive cervical carcinoma of Western Australian women

The presence of human papillomavirus (HPV) types 11, 16 and 18 in 77 biopsies of cervical intraepithelial neoplasia (dysplasia) and carcinoma of the uterine cervix of a sample of women from Western Australia was examined using "Southern" blot hybridisation. HPV-DNA was found in 17 of the 23 dysplasias and 43 of the 54 invasive carcinomas examined but not in the 5 biopsies obtained from areas assessed as normal by colposcopy and histology. Five of 11 biopsies of mild to moderate dysplasias contained HPV type 11 (HPV-11), 2 HPV-16 and 1 HPV-18. Of 12 severe dysplasias/carcinoma in situ, 2 contained HPV-11, 4 HPV-16 and 2 HPV-18. One biopsy contained both HPV-11 and HPV-16. Of 45 squamous cell carcinomas examined for HPV-DNA, 24 contained HPV-16, 5 HPV-11 and 1 HPV-18. Both HPV-11 and HPV-16 were found in 6 of the squamous cell carcinomas and 2 contained both HPV-16 and HPV-18. Of 6 adenosquamous carcinomas examined, 3 contained HPV-DNA, 2 with HPV-16 and 1 with HPV-11. HPV types 16 or 18 were also found in 2 of 3 adenocarcinomas. This study shows a strong association between the papillomavirus and uterine cervical cancer in a sample of women from Western Australia. HPV-16 was more frequently associated with severe dysplasia and cancer than with mild or moderate dysplasia supporting the view that this HPV genotype may have a greater oncogenic potential than HPV-11.

Comparison of peroxidase-antiperoxidase and avidin-biotin complex methods for the detection of papillomavirus in histological sections of the cervix uteri

A study was undertaken to determine the relative sensitivities of the peroxidase-antiperoxidase (PAP) and avidin-biotin complex (ABC) methods for the detection of human papillomavirus (HPV) antigens in acetic acid-ethanol fixed paraffin-embedded cervical tissue. Tissue sections prepared from 14 women suspected to have HPV infections with either atypia or dysplasia were stained immunohistochemically using an antiserum against genus-specific (common) antigen of bovine papillomavirus. Detection of HPV antigen was approximately twice as frequent by the ABC method as by the PAP method. Of the 14 cases studied, 43% were found to be HPV positive by the PAP method whereas 79% were HPV positive by the ABC method. In addition, the number of cells found to be HPV positive by the ABC method was approximately double the number by the PAP method.