Human papillomavirus testing in primary cervical screening

Correlation of cervical carcinoma and precancerous lesions with human papillomavirus (HPV) genotypes detected with the HPV DNA chip microarray method

BACKGROUND

Human papillomavirus (HPV) infection is considered to play an important role in the development of cervical carcinoma, and it is known that certain HPV types, such as HPV-16 and HPV-18, are highly associated with cervical carcinoma. However, the pathologic behavior of other HPV types remains unclear. Recently, a new HPV detection technique, the HPV DNA chip, was introduced. The HPV DNA chip harbors 22 HPV probes and has the advantage of being able to detect 22 HPV types simultaneously. To evaluate the quality of the HPV DNA chip method and to identify HPV types related to cervical carcinoma and precancerous lesions, the authors performed HPV typing in cervical specimens from 1983 patients and compared their cytologic and histologic diagnoses.

METHODS

The HPV DNA chip was used for HPV typing. Among 1983 patients who were tested for HPV types, cervical smear cytology was performed in 1650 patients, and 677 of those patients underwent cervical biopsy.

RESULTS

Among the 1650 smears that were examined cytologically, 92.7% (114 of 123 smears) of low-grade squamous intraepithelial lesions (LSILs), 98.1% (106 of 108 smears) of high-grade squamous intraepithelial lesions (HSILs), and 96.3% (51 of 53 smears) of carcinomas were HPV positive, compared with only 35.1% of smears with normal cytology that were HPV positive. HPV-16 was the most prevalent type (chi-square test; P < 0.01) in LSILs (28.5%), in HSILs (51.9%), and in carcinomas (62.5%) followed by HPV-58 and a group of low-risk types (HPV-6, HPV-11, HPV-34, HPV-40, HPV-42, HPV-43,and HPV-44) in LSILs. HPV-58 (15.7%), HPV-18 (6.7%), and HPV-52 (4.6%) were the next most prevalent types after HPV-16 in HSILs. HPV-18 (11.4%) and HPV-58 (11.4%) were the second most common types in carcinomas. HPV-58 had the highest positive predictive value (54.9%) for the detection of histologically confirmed HSIL or carcinoma, whereas HPV 16 had the highest negative predictive value (80.6%). The sensitivity (96.0%) of the HPV test using the DNA chip method for detecting HSIL or carcinoma was superior compared with the sensitivity of cytologic diagnosis (83.6%).

CONCLUSIONS

The HPV DNA chip provides a very sensitive method for detecting 22 HPV genotypes with reasonable sensitivity (96.0%) and reasonable negative predictive value (96.9%), and it overcomes the low sensitivity of cytologic screening for the detection of HSIL or carcinoma. HPV-58, HPV-52, and HPV-56, as well as HPV-16 and HPV-18, were associated highly with HSIL and carcinoma in the current large series. In addition, multiple HPV infection was associated less frequently with cervical carcinoma and with precancerous lesions compared with normal cytology.

The case for early detection

Early detection represents one of the most promising approaches to reducing the growing cancer burden. It already has a key role in the management of cervical and breast cancer, and is likely to become more important in the control of colorectal, prostate and lung cancer. Early-detection research has recently been revitalized by the advent of novel molecular technologies that can identify cellular changes at the level of the genome or proteome, but how can we harness these new technologies to develop effective and practical screening tests?

Thin-layer liquid-based cervical cytology and PCR for detecting and typing human papillomavirus DNA in Flemish women

The objective of this study was to document the occurrence and to correlate the prevalence of different human papillomavirus (HPV) types with the cytological results on simultaneously performed thin-layer preparations in a large population of Flemish women. During 1 year, 69 290 thin-layer preparations were interpreted using the Bethesda classification system. Using an algorithm for HPV testing based on consensus primers and type-specific PCRs in combination with liquid-based cytology, we determined the occurrence and distribution of 14 different oncogenic HPV types (16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, 66 and 68). Reflex HPV testing was performed on cytologically abnormal samples and on an age matched randomly selected control group with normal cervical cytology (n=1351). Correlation between cytology, age and prevalence for the 14 different high-risk HPV types is given. There is a significant increase in predominance of high-risk HPV types, with increasing abnormal cytology. Coinfection with multiple HPV types also increased with cytological abnormalities, and was highest in HSIL (16.7%). In Flanders, HSIL was most often associated with HPV types 16, 33, 35, 31, 18 and 51. Using thin-layer liquid-based cytology and PCR to detect HPV, it is feasible to screen large numbers of women.

Can cervical cancer screening be stopped at 50? The prevalence of HPV in elderly women

Although the relation between cervical cancer and the human papillomavirus (HPV) has been established beyond doubt, the introduction of HPV detection in cervical cancer screening is halted, primarily by the high rate of false positivity in relation to morbidity, since the majority of women infected with HPV will not develop lesions. To counteract overconsumption of cervical cancer screening in elderly women, we wanted to test the hypothesis that women of 50 years or older who are HPV-negative and have a cytologically normal smear might be encouraged to refrain from further screening. As a first step, the prevalence of high-risk HPV in a population of 1,936 women of 50 years and older was investigated. After an initial decline, a slightly higher prevalence can be seen with increasing age. There is a decrease in the prevalence of multiple infections with age, paralleled by an increase in single infections, especially of HPV type 16 in the eldest-age group. However, neither the decrease in multiple infections nor the increase in single infections is statistically significant. The data obtained in this study show that, even in the presence of a slight increase in the HPV prevalence in elderly women, approximately 94% of the elderly women can be withdrawn from the cervical cancer screening. However, a follow-up study will be necessary to determine the frequency of (re)infection as well as the course of an HPV infection in elderly women.

Telecolposcopy - a feasibility study in primary care

Organized cervical screening has reduced the incidence of invasive cervical cancer, but this has resulted in large numbers of women requiring investigation. We have investigated the negative predictive value of colposcopy and used telemedicine to develop a secondary screening technique for use in primary care. A video-colposcope was used to record video-clips, which were subsequently transmitted to a specialist for interpretation. The gold standard for the comparison was the opinion of the colposcopist who examined the women in the hospital colposcopy clinic. Eighty-one out of 97 women were studied by both techniques. Using a diagnosis of normal or abnormal, telecolposcopy had a sensitivity of 88.9% and a specificity of 93.3%. There was very good agreement between the telecolposcopy screener and the colposcopist (Cohen s kappa statistic = 0.70). Furthermore, telecolposcopy screening did not grade any cases of colposcopic high-grade cervical intraepithelial neoplasia as normal. The pilot study has established the validity of diagnosing from transmitted computerized video-clips.

Paying for prevention standardizing the measurement of the value of health care interventions

It is not clear if spending more on tests that enhance the accuracy of Pap smears would lead to a greater reduction in cancer incidence than if the money were spent to include a greater proportion of women in primary screening. The cost effectiveness of tests beyond the Pap smear has not been clearly demonstrated. There is the question of whether cervical cancer incidence can be decreased more by improving the tests for patients who are already screened or by improving access to the unscreened population. Cervical cancer screening represents only one of many public health issues competing for resources. Given that there are choices to be made, the optimal yardstick against which all resource-competing programs are measured should be marginal benefit versus marginal cost.

Numerical aberrations of chromosome 1 in cervical intraepithelial neoplasia are strongly associated with infection with high-risk human papillomavirus types

The aims of this study were to assess the relationships between numerical aberrations of chromosome 1 and the presence of high-risk human papillomavirus (HPV). Five normal samples, 11 CIN1, 13 CIN2, 18 CIN3, and nine carcinomas were studied by in situ hybridization (ISH), using a DNA probe for the centromere of chromosome 1 (cen#1) and a DNA probe cocktail for HPV types 16 and 18. A short fragment polymerase chain reaction hybridization line probe assay (SPF-PCR-LiPA) technique was used to detect 25 HPV types. The mean number of cen#1 per nucleus (chromosome index, CI) was measured, and the fractional areas of dysplastic epithelium with HPV16/18 infection and with cen#1 aneusomy were estimated. Disomy was found in all normal epithelium and in 36% of CIN1. Tetrasomy was observed in 64% of CIN1, 15% of CIN2, and 17% of CIN3. Hyper-tetrasomy was observed in 77% of CIN2, 83% of CIN3, and 100% of invasive carcinomas. High-risk HPVs were present in 20%, 75%, and 94% of disomic, tetrasomic, and hyper-tetrasomic lesions, respectively. The mean CI value was significantly higher in the lesions infected with high-risk HPV than in the lesions not infected by high-risk HPV (p < 0.001), due to the significantly higher prevalence of hyper-tetrasomy. The ISH study disclosed that HPV16/18 was exclusively found within dysplastically altered epithelium. The area with aneusomy is mostly enclosed within the area infected with HPV. In 83% of the HPV16/18-positive CIN lesions, the fractional area of HPV-infected epithelium was equal to, or larger than, the fractional area with aneusomy. In conclusion, aneusomy for chromosome 1 is strongly associated with high-grade CIN lesions and infection with high-risk HPV; it is likely that the occurrence of numerical aberrations of chromosome 1 is preceded by infection with high-risk HPV.

Human papillomavirus testing for triage of women referred because of abnormal smears. a decision analysis considering outcomes and costs

The objective of this article was to evaluate the utility of high-risk human papillomavirus (HR-HPV) testing for triage of women referred for colposcopy because of abnormal smears. We considered women with persistent mild or moderate dyskaryosis and women with severe dyskaryosis who were referred for colposcopy. For both patient groups we evaluated three alternative management policies: (1) conventional management based on histological assessment; (2) HR-HPV-triage with direct treatment without prior histologic assessment for HR-HPV-positive women and conventional management for HR-HPV-negative women; and (3) direct treatment without histologic assessment for all referred women. For each policy the average number of medical procedures, doctor visits, and the costs per referred woman were calculated. Based on a literature review, the results were tested and translated to other patient groups. Per woman with persistent mild or moderate dyskaryosis and compared with conventional policy, HR-HPV-triage will avoid 0.51 colposcopically directed biopsies, but adds 0.05 local treatments of the cervix (i.e., loop excision of the transformation zone) and 0.09 outpatient visits, and will cost $134 US dollars extra. HPV triage is less efficient in women with borderline or mildly dyskaryotic cytology. In women with severe dyskaryosis, direct treatment is more efficient as conventional management or HPV triage. The decision to introduce HPV testing or direct treatment in women with persistent mild or moderate dyskaryosis strongly depends on the relative burden attributed to a colposcopically directed biopsy and an outpatient visit compared to loop excision of the transformation zone treatment of the cervix. For women with severe dyskaryosis, direct treatment should be seriously considered.

Cytologic screening and human papilloma virus test in women undergoing artificial fertilization

BACKGROUND

Infertile women in Sweden are offered in vitro fertilization (IVF) within the frame of the social security system. The present investigation was undertaken to evaluate the prevalence of genital human papilloma virus (HPV) infection in relation to the results of cytologic screening and to the infertility in these women.

MATERIAL AND METHODS

Two hundred and fourteen women, mean age 32 years (range 20-40), admitted to the Center for Reproduction at Uppsala University Hospital for investigation of infertility and IVF were studied. Human papilloma virus tests were performed by a sensitive polymerase chain reaction-based technique in cervical smears obtained at a medical examination or during oocyte retrieval. Cytologic screening results were obtained from medical records or at the time of investigation. The infertile women were compared with 197 healthy female controls.

RESULTS

Infertility resulted from female factors in 47% and male factors in 29% of the cases, and remained unexplained in 24%. Seven percent of the infertile women were HPV-positive compared with 9.1% of the controls. Only genital and oncogenic HPV types were identified. Human papilloma virus type 16 was most prevalent, and examination of the HPV 16 E6 gene showed that this prototype predominated over variants. No correlation was found between HPV infection and cause of infertility. Abnormal cytology was observed in 2.3% of the infertile women and 4.1% of the controls.

CONCLUSIONS

Human papilloma virus infections might appear somewhat less frequently in infertile women admitted for IVF than in a control population. In both groups HPV infection was more common than cytologic abnormalities, possibly indicating that present HPV tests are more sensitive in detecting HPV infections than cytologic screening.

High prevalence of human papillomavirus (HPV) infections and high frequency of multiple HPV genotypes in human immunodeficiency virus-infected women in Brazil

A group of 208 human immunodeficiency virus (HIV)-infected women in Brazil were studied for the presence of human papillomavirus with the general SPF(10) PCR primer set. Virtually all (98%) women were found positive for human papillomavirus (HPV) DNA. Genotyping by the reverse hybridization line probe assay (HPV-LiPA) revealed a high prevalence of multiple genotypes (78.9% of the cases), with an average of 3.1 genotypes per patient (range, 1 to 10 genotypes). HPV 6 was the most prevalent genotype and was observed in 80 (39.2%) patients, followed by types 51 (31.9%), 11 (26.0%), 18 (24.0%), and 16 (22.5%). Of the genotypes detected, 40.9% were low-risk genotypes. Twenty-two (10.5%) patients showed normal (Pap I) cytology, 149 (71.6%) patients had inflammation (Pap II), and 28 patients (13.4%) had a Pap III score. The prevalence of high-risk genotypes increased with the cytological classification. There were no significant associations between the number of HPV genotypes detected and the cytological classification, HIV viral load, and CD4 count in these patients. In conclusion, the highly sensitive SPF(10) LiPA system shows that a very high proportion of HIV-infected women in Brazil are infected with HPV and often carry multiple HPV genotypes.

Autofluorescence spectroscopy for the diagnosis of cervical intraepithelial neoplasia

OBJECTIVE

To assess the feasibility of autofluorescence spectroscopy in the diagnosis of cervical intraepithelial neoplasia (CIN) using broadband light excitation.

DESIGN

Feasibility study.

SETTING

Colposcopy clinic of an university hospital.

POPULATION

Sixty-eight patients at risk for CIN.

METHODS

After excitation with a broadband light between 375 and 440 nm, spectral distribution of native tissue fluorescence (autofluorescence) was acquired from 685 cervical sites for the localisation and differentiation of CIN, and compared with colposcopically directed biopsy and human papillomavirus (HPV) DNA testing.

MAIN OUTCOME MEASURE

Detection of CIN.

RESULTS

The evaluation of spectral measurements revealed significantly lower autofluorescence values for CIN 3 lesions compared with normal tissue (P < 0.001), and compared with CIN 1 or CIN 2 (P < 0.002). High grade CIN lesions (CIN 2/3) presented with a significant reduced autofluorescence compared with CIN 1 (P < 0.002). Patients with a positive HPV DNA testing showed a significantly lower autofluorescence than patients tested negative for HPV DNA (P < 0.05). Severe inflammation such as chronic cervicitis may lead to false positive results.

CONCLUSIONS

Autofluorescence spectroscopy represents an interesting approach for the detection of cervical neoplasia. Using an excitation wavelength band between 375 and 440 nm, significant differences between normal and precancerous lesions of the cervix can be seen.

Primary screening for high risk HPV by home obtained cervicovaginal lavage is an alternative screening tool for unscreened women

BACKGROUND/AIMS

Self sampling is considered an adjuvant tool to facilitate the participation of women in cervical cancer screening programmes. This study aimed to evaluate whether cervicovaginal lavage could be an alternative for the cervical smear in cytology and human papillomavirus (HPV) testing and to assess the acceptance of the self sampling device by women.

METHODS

Fifty six women with abnormal cervical cytology (very mild dyskaryosis or worse) and 15 women with normal cervical cytology obtained a self collected cervicovaginal lavage at home and filled in a questionnaire on the use of the device. At the colposcopy clinic the gynaecologist performed the same procedure followed by a cervical smear for cytology and HPV DNA testing.

RESULTS

The self sampling device was acceptable to 88% of the women. The concordance between the cytology results in the smear and the lavage by the doctor and the patient was 54% and 41%, respectively (kappa = 0.28 and 0.14). The concordance between high risk HPV detection in the smear and the lavage by the doctor and the patient was 93% and 78%, respectively (kappa = 0.82 and 0.53). Ninety one per cent of the women with high grade cervical intraepithelial neoplasia (CIN) had a high risk HPV positive test in the smear, compared with 91% and 81% in the lavages taken by the doctor and the patient, respectively.

CONCLUSIONS

HPV DNA testing by home obtained samples is useful as a screening tool for cervical cancer, whereas cervical cytology by self sampling is not. Although the sensitivity for high grade CIN by high risk HPV testing in the lavage by the patient is not significantly lower than that in the cervical smear, self sampling for HPV DNA is a feasible alternative method in women who decline to participate in population based cervical cancer screening programmes. However, participation in the screening programme remains the best option.

The causal relation between human papillomavirus and cervical cancer

The causal role of human papillomavirus infections in cervical cancer has been documented beyond reasonable doubt. The association is present in virtually all cervical cancer cases worldwide. It is the right time for medical societies and public health regulators to consider this evidence and to define its preventive and clinical implications. A comprehensive review of key studies and results is presented.

Persistent human papillomavirus infection and smoking increase risk of failure of treatment of cervical intraepithelial neoplasia (CIN)

Women with abnormal smears have an increased risk of developing cervical cancer. During the 8 years following conservative treatment of cervical intraepithelial neoplasia (CIN), their risk of invasive cervical cancer is about 5 times greater than that of the general population. Human papillomavirus (HPV) has been associated with the natural history of both CIN and cervical cancer. To date, there have been no published reports on the predictive value of HPV testing in the treatment outcome of CIN. A prospective, multi-center, cohort study was conducted on women in the Northwest of England who were attending for treatment of CIN. They were asked to complete a questionnaire, which included a detailed smoking history. Pre- and post-treatment HPV testing was performed on cervical biopsies and cervical swab, being taken with the first follow-up smear at 6 months. A nested case-control analysis was performed, cases being defined as women who developed CIN within the 2 years of treatment and controls being sampled from those who did not experience treatment failure within 2 years. Multiple conditional logistic regression is used to study the factors associated with treatment failure of CIN. The cohort included 958 women of whom 77 (8%) experienced treatment failure (cases). Two controls were matched to each case (154). Smoking status was significantly associated with CIN treatment failure(p= 0.0013). Current smokers had a 3-fold increased risk of treatment failure of CIN as compared to non-smokers (95% CI 1.65 to 5.91). Five hundred twenty-five women underwent HPV sampling following treatment, of whom 47 (8.9%) developed further CIN. Post-treatment positive HPV testing was found to be strongly associated with treatment failure of CIN (OR 23.3; 95% CI 3.15-172.1). In 11/45 cases with negative smear at first follow-up, the HPV test was positive. The combination of both HPV and cytology in the first follow-up visit predicted treatment failure in 72% of the cases. Cigarette smoking is a factor, which, independently of HPV infection, influences the treatment outcome of CIN. Smokers and those who are HPV positive during follow-up appear to require longer, more intensive follow-up. HPV testing requires careful consideration as part of routine follow-up protocol following treatment of CIN.

Psychosocial and economic aspects of a trial of management of mild and borderline cervical abnormalities (TOMBOLA)

TOMBOLA is a randomized controlled trial to determine (a) the most effective and efficient management strategy for women with borderline or mildly dyskaryotic cervical smear results, and (b) the most appropriate treatment for women with abnormalities detected following colposcopy. This paper outlines the trial's psychosocial and economic protocol, and explains how TOMBOLA can provide detailed evidence on the psychosocial and economic impact of alternative management options and follow-up. This protocol has been developed in parallel with the clinical protocol, thereby offering the opportunity for the development of a type-specific outcome measure and detailed piloting of all instruments. The multi-disciplinary approach to TOMBOLA allows the combination of clinical outcomes with both generic and specific psychosocial and health-related quality of life measures. The convergent validity between these measures will be assessed, with a view to developing a specific utility index for the future assessment of cervical screening modalities.

Molecular detection and genotyping of human papillomavirus

Human papillomavirus infections are associated with the development of cervical neoplasia. Human papillomavirus is a group of heterogeneous viruses, comprising many genotypes, which can be divided into high-risk and low-risk types, depending on their association with disease. Therefore, accurate molecular diagnostic tools are required for detection and identification of human papillomavirus. Monitoring of human papillomavirus infection is necessary for adequate patient management and follow-up during treatment. This review describes the different molecular methods available for human papillomavirus detection and identification of genotypes.

Primary screening for human papillomavirus infection

As human papillomavirus infection is now known to be a necessary risk factor for at least 95% of cervical cancers, the medical community has a responsibility to assess and evaluate how this knowledge should best be used for the prevention of cervical cancer. Organized screening strategies combining cytological screening with human papillomavirus testing in older age groups could theoretically be more sensitive than current screening programmes in reducing the incidence of cervical cancer. If it is possible safely to extend the screening interval in human papillomavirus-negative women, such programmes could also both be more effective and more cost-efficient. Although some modelling studies have indicated that this could indeed be the case, evidence from clinical trials evaluating the long-term protective effect of primary human papillomavirus screening is still lacking. The key issues on the research agenda for primary human papillomavirus screening are reviewed.

Early withdrawal from cervical cancer screening: the question of cost-effectiveness

In countries such as the UK, mass population screening for cervical cancer has been undertaken since the 1960s. Although of established effectiveness, no formal evaluation of the screening protocol was carried out prior to its implementation. On the basis of a published mathematical modelling exercise, it has been speculated that withdrawing women from the screening programme at an earlier age than at present, whilst leading to a higher rate of invasive cervical cancer (ICC), could reduce resource use. Using estimates of screening and treatment costs, and of expected life-years lost following earlier withdrawal, we simulated cost-effectiveness ratios for various scenarios described by the model. Median cost savings resulting from a life-year lost never exceeded pound10000 for any scenario, although the estimates were particularly sensitive to the assumed age at cancer presentation and the rate of cancer progression. Our findings seem to offer little economic support for the early withdrawal of subjects from the cervical screening programme.

Expanded cytological referral criteria for colposcopy in cervical screening: comparison with human papillomavirus testing

OBJECTIVE

The goal of this study was to investigate whether expanded cytologic referral criteria for colposcopy or the addition of human papillomavirus (HPV) testing on cervical screening could improve the rates of detection of cervical intraepithelial neoplasia (CIN).

METHODS

HPV testing by semiquantitative polymerase chain reaction/ELISA was performed in 1000 women who were self-referred for routine Pap smear. They underwent colposcopy following an abnormal smear result or a positive HPV test. As abnormal smear results were considered reports of low- or high-grade squamous intraepithelial lesion, atypical squamous cells of undetermined significance, and even HPV-associated reactive cellular changes (mild koilocytosis, mild dyskeratocytosis, hyperchromatic nuclei, bimultinucleation, and cleared cytoplasm). Loop excision of the transformation zone was performed in women with cytology and colposcopy indicative of CIN, as well as in women with normal cytology but positive HPV test and colposcopic impression of CIN.

RESULTS

The Pap test was abnormal in 89% of the cases of CIN 1 (34/38) and 96% of CIN 2/3 (27/28) diagnosed in our population. HPV testing picked up four additional cases of CIN 1 (11%) and one case of CIN 2/3 (4%). Overall the HPV test detected 95% of the cases of CIN 1 (36/38) and 89% of the cases of CIN 2/3 (25/28).

CONCLUSION

HPV testing does not appear to add significantly to cytology in terms of positive predictive value or detection rate, if extended cytologic indications for colposcopy are used.

An update on human papillomavirus infection and Papanicolaou smears in adolescents

Human papillomavirus infection is one of the most common sexually transmitted infections in young women, and may lead to clinical sequelae such as anogenital condylomata and cervical squamous cell carcinoma. Recent data on the biology and natural history of HPV infection in adolescents will have important implications for the development of adolescent-specific protocols for cervical cancer screening and for follow-up of abnormal cytology.

Human papillomavirus testing in primary screening for the detection of high-grade cervical lesions: a study of 7932 women

High-risk human papillomaviruses (HR-HPV) are the necessary cause of cervical carcinomas. To determine whether HPR-HPV DNA detection in primary routine screening could represent a sensitive and reliable technique for the detection of high-grade squamous intraepithelial lesions (HGSIL), laboratory analysis using 2 cytologic techniques (conventional and liquid-based), HPV testing with Hybrid Capture II assay (HC-II), followed by colposcopic examination of women with abnormal cervical finding and/or persistent HR-HPV infection, was conducted in 7932 women who had routine cervical examination. The sensitivity of HPV testing for detecting a histologically proven HGSIL was 100%, higher than that of conventional (68.1%) and liquid-based (87.8%) cytology. The low specificities of 85.6% and 87.3% of HPV testing slightly increased to 88.4% and 90.1% if HPV testing was reserved for woman >30 years old. The quantitative approach provided by the HC-II assay for the assessment of the viral load was not reliable for predicting HGSIL in normal smears. HR-HPV testing could be proposed in primary screening in association with cytology. With conventional cytology it significantly improves the detection of HGSIL. With the use of the same cervical scrape for HPV testing and liquid-based cytology, HR-HPV testing would allow to select positive samples treated in a second time for cytology which gives a good specificity.

Comparative analysis of human papillomavirus infections in cervical scrapes and biopsy specimens by general SPF(10) PCR and HPV genotyping

Human papillomavirus (HPV) can be detected by DNA amplification from clinical samples. The aim of the present study was to compare the HPV status in both cervical scrape and biopsy specimens obtained from 174 patients, using the recently developed broad spectrum SPF(10) PCR-LiPA method. The detection rate of HPV in these materials was determined and the spectrum of HPV genotypes was compared. Cervical scrapes and biopsy specimens were obtained, either on the same day (group I), or with an interval of up to almost 2 years (group II, mean interval 97 days, range 1-469 days). HPV DNA was amplified by SPF(10) PCR and detected in a microtitre plate hybridization assay. Of the HPV-positive cases, the genotype was determined by reverse hybridization of the same SPF(10) amplimer on a line probe assay (LiPA), discriminating between HPV genotypes 6, 11, 16, 18, 31, 33-35, 39, 40, 42-45, 51-54, 56, 58, 59, 66, 68, 70, and 74. The results showed that the detection rate and the spectrum of HPV genotypes in cervical scrapes and the corresponding biopsy specimens were highly comparable in both patient groups, even when multiple genotypes were present. In both groups, multiple HPV genotypes were more frequently detected in cervical scrapes than in the corresponding biopsy specimens. In conclusion, HPV infection can be diagnosed in cervical scrapes and biopsy specimens using the SPF(10) PCR-LiPA system. Analysis of cervical scrapes accurately reflects the spectrum of HPV genotypes in the patient's cervical region, even with a sampling interval between the cervical scrape and the biopsy specimen.

Will New Human Papillomavirus Diagnostics Improve Cervical Cancer Control Efforts?

With the causal link between specific types of human papillomavirus (HPV) and cervical cancer firmly established, efforts have turned to assessing the relative merits of offering HPV testing in screening, triage, and posttreatment management. Many unanswered questions remain, but a growing body of evidence supports a role for HPV testing in cervical cancer prevention programs. Already, clinical centers that serve thousands of women in Europe and the United States have incorporated HPV DNA tests in triage algorithms.

Significance of high-risk human papillomavirus detection by polymerase chain reaction in primary cervical cancer screening

The purposes of this study were to evaluate the incidence of high-risk human papillomavirus (HPV) infection by polymerase chain reaction (PCR) and to assess its diagnostic usefulness in primary cervical screening. PCR testing for HPV type 16, 18, 31 and 33 was performed on 1305 specimens obtained during routine cervical cancer screening. We analysed the concurrent cervical smears and biopsy, and correlated them with the HPV infection status. We also evaluated histologically-proven cases with ASCUS smears according to HPV infection. HPV DNA was identified in eight (0.7%) of 1144 cytologically normal patients; nine (10.5%) of 86 ASCUS; seven (25.0%) of 28 LSIL; 26 (78.8%) of 33 HSIL; and in all of three squamous cell carcinomas (SCC). HPV positivity was significantly associated with cytohistological diagnosis for HSIL of more. In addition, HPV-positive ASCUS cases were found to be associated with histological abnormality rather than HPV-negative. The results indicate that high-risk HPV testing by PCR could be a useful adjunct tool for Pap smear in primary cervical screening. The combination of Pap smear and high-risk HPV testing by PCR might reduce unnecessary colposcopy-guided biopsy of women with cytological diagnosis of ASCUS.

Estimating prevalence when the true disease status is incompletely ascertained

We discuss the problem of estimating the number of cases not identified in studies of two or more screening tests in which not all individuals are fully evaluated. In particular we consider studies in which only those individuals who are positive on a screening test have a complete diagnosis. We show how to adjust for individuals who are not fully evaluated despite recommendation for referral and for cases not identified among those negative on all screening tests. The assumptions under which these adjustments are valid are discussed. A proposal is made for analysis of studies using three screening tests. Estimation of and inference about the disease prevalence and the test sensitivity when disease status is ascertained on a random sample of those negative on both screening tests is discussed.

Diagnosing human papillomaviruses: recent advances

The biological importance of a group of human papillomaviruses, known as high-risk human papillomaviruses, as the key causal agent for almost all cervical cancer has now been established. Many aspects of the natural history of high-risk human papillomaviruses as sexually transmitted infections and as oncogenic agents have been researched. Although human papillomavirus diagnosis is largely confined to DNA detection techniques in cervical smears, there is accumulating evidence that the best polymerase chain reaction and hybrid capture techniques are more sensitive and probably of similar specificity compared with cervical cytology as a triage test for women with borderline smear abnormalities and for screening older women. This is strong presumptive evidence that high-risk human papillomavirus testing could be useful in cervical screening. Current research is aimed at establishing a place for high-risk human papillomavirus testing in routine screening practice. Randomised clinical trials, long-term natural history studies, mathematical modelling, and economic and psychosocial studies are being used to demonstrate whether this testing can improve both the effectiveness and efficiency of cervical screening in a range of situations.

Colposcopically directed biopsy findings in the young female

STUDY OBJECTIVE

To evaluate the colposcopic findings of cervical alterations in the young sexually active female.

DESIGN, SETTING, PARTICIPANTS

Colposcopic examination and follow-up of 51 young sexually active females aged 15-20 yr was conducted due to abnormal cytology or a suspicious abnormality of the cervix. The study was conducted at the Colposcopy Units of the 1(st) and 2(nd) Departments of Obstetrics and Gynecology, University of Athens, Greece. ONTERVENTIONS: Colposcopic examination, LEEP, conization.

MEAN OUTCOME MEASURES

Biopsy, human papillomavirus (HPV) typing.

RESULTS

Colposcopic examinations were within normal limits in 8 of 51 (15.7%) cases. Cervical alterations were related to HPV infection in 14 cases (27.4%), to cervical intraepithelial neoplasia (CIN) I in 15 (29.4%) cases, to CIN II in 13 (25.5%) cases, and to CIN III in 1 (2.0%) case. Of all CIN I cases, 8 of 15 (53.3%) were HPV positive, and HPV type 11, 16, 18, 31, 33, and 11& 16 were found. In CIN II cases, 5 of 13 (38.4%) were HPV positive, and HPV type 11, 16, 18, and 11 & 31 were found. In the CIN III case, only HPV type 16 was found.

CONCLUSIONS

Our findings strongly confirm the necessity of obtaining cervicovaginal smears on all sexually active gynecologic and obstetric teenage patients. Colposcopy plays a major role in the evaluation of the cervix and in the treatment that should be given for any individual CIN lesion.

Cervical screening in England and Wales: its effect has been underestimated

Opinions about cervical screening in the UK tend to follow one of two negative lines of thought. The first is that cervical cancer is a rare disease, and too much time and effort are spent on screening. The second is that it has been relatively ineffective, since incidence of invasive carcinoma did not fall until the NHS Cervical Screening Programme (NHSCSP) was introduced in 1988, although it fell by 40% since then. This paper presents publicly available data to demonstrate that neither of these views is true. Registrations of invasive carcinoma of the uterine cervix and carcinoma in situ in England and Wales between 1971 and 1996 show that a substantially increased risk of disease in women born since 1940 has been reversed, almost certainly by greatly improved screening. Cervical carcinoma is now a rare disease because most cases are prevented before they become invasive, mostly by screening young women, aged 20-40, before the decade of life when symptomatic cervical carcinoma most frequently presents.

Prediction of high-grade cervical intraepithelial neoplasia in cytologically normal women by human papillomavirus testing

Human papillomavirus (HPV) testing has been suggested for primary screening of cervical cancer. Prediction of future high-grade cervical lesions is crucial for effectiveness and cost. We performed a case control study in a retrospective cohort of women with at least two cervical smears, all but the last one being negative, from the organized cervical screening programme in Florence, Italy. We searched for high-risk HPV in all previous, archival, smears from cases (new histologically confirmed cervical intraepithelial neoplasia (CIN) grade II or worse) and in one previous smear from each control (last smear cytologically normal, matched by age and interval (latency) from last smear). We applied polymerase chain reaction (PCR), and the b-globin gene was used as a DNA preservation marker. High-risk HPV was identified in 71/92 (77.17%) previous smears from 79 cases and 17/332 controls (5.12%). The odds ratio (OR) was 63.76 (95% CI 30.57-132.96). Among cases the proportion of HPV-positive smears declined slightly with increasing latency. Among cases, HPV was found in 81.24% (95% CI 69.93-88.96%) of smears with latency < 4 years and in 67.80% (95% CI 47.72-82.93%) of those taken at longer intervals, up to 6 years. These findings suggest that testing for high-risk HPV allows predicting 80% of CINII/III 3 years before the cytological diagnosis and two thirds 6 years before. They also suggest that testing women negative for high-risk HPV at longer interval and strictly following-up women who are HPV positive could be an effective strategy for cervical cancer screening.

Cervical cancer screening in Sweden

Organised cervical cancer screening was implemented in Sweden in the mid-1960s. A marked decline in cervical cancer incidence could be attributed to the time-point of start of screening. Squamous cell carcinoma has declined by 60%, whereas adenocarcinoma has increased. About 950000 papanicolaou (Pap) smears are taken annually. Only 31% of the smears taken in the organised screening programme. As of 1998, the screening guidelines are 3-yearly tests between 23 and 50 years of age and 5-yearly tests between 50 and 60 years of age. The article reviews the screening practise in Sweden, the current efforts to improve the quality of the screening programme, as well as the ongoing randomised evaluations of organised primary screening for cervical human papilloma virus (HPV) infection.

Usefulness of human papilloma virus testing in the screening of cervical cancer precursor lesions: a retrospective study in 314 cases

OBJECTIVE

To assess the usefulness of human papilloma virus (HPV) typing for predicting pre-malignant and malignant cervical lesions.

STUDY DESIGN

314 women, who underwent colposcopy, biopsies and high and low-risk HPV typing after a confirmed abnormal routine Pap test were studied. HPV-DNAs were typed by using PCR technique.

RESULTS

We found a significant increasing rate of high-risk-HPV by the increasing severity of histology, ranging from 40% in negative cases to 86.9% in those with CIN3 lesions. The positive predictive value of high-risk-HPV ranged from 13.3% in patients with atypical squamous cells of undetermined significance (ASCUS) to 29.4% in those with HSIL. By contrast, negative predictive value was 96% in patients with ASCUS, 97.2% in low-grade squamous intraepithelial lesions (LSIL), and 71.4% in high-grade squamous intraepithelial lesions (HSIL). Sensitivity and specificity for detecting CIN2 or CIN3 was 86.0% and 41.3%, respectively.

CONCLUSIONS

The high negative predictive value of high-risk HPV testing suggests that HPV negativity could be used for predicting the absence of important cervical lesions, and therefore avoiding unnecessary colposcopy in ASCUS and LSIL cases.

Speculoscopy for Triage of Patients with an Abnormal Pap Smear: Data from the GISPE Study

OBJECTIVE

This study evaluates the performance of Papanicolaou smear combined with speculoscopy in improving the predictive value of minor grade cervical cytological abnormalities.

MATERIALS AND METHODS

A total of 3,300 asymptomatic women who had routine cervical smears were studied in 32 Italian centers. All these women underwent Pap smear and speculoscopy. The women positive at Pap smear or speculoscopy (n = 908) were referred for colposcopy and directed punch biopsy/endocervical curettage was performed when appropriate.

RESULTS

Of the 908 patients referred for colposcopy, 538 underwent biopsy; 92 of these had a cervical lesion (cervical intraepithelial neoplasia [CIN]) confirmed on histology (67 CIN1 and 25 CIN2-3). Speculoscopy pointed out an area to biopsy in 84% of the CIN1 and in 75% of the CIN2-3 cases among women who showed minor (low-grade squamous intraepithelial lesion or less) cytological abnormalities.

CONCLUSIONS

The potential combination of cytology and speculoscopy as an intermediate test in patients with minor grade cytologic (atypical squamous cells of undetermined significance or low-grade squamous intraepithelial lesion) cervical changes may decrease the number of recalls and directed biopsies in a cost-effective manner.

A systematic review of the role of human papilloma virus (HPV) testing within a cervical screening programme: summary and conclusions

A systematic review of the available evidence on the role of HPV testing in cervical screening has been published by the Health Technology Assessment Committee of the UK Department of Health. The review summarized relevant data on testing methods, natural history, and prevalence of the virus in different disease groups. Cost-effectiveness modelling was undertaken. Ten major conclusions were reached and are reported here. The key conclusions were that HPV testing was more sensitive than cytology, but that there were concerns about specificity, especially in young women. The increased sensitivity led to a recommendation that HPV testing be introduced on a pilot basis for women with borderline and mild smears. HPV testing has great potential as a primary screening test, but large trials are needed to properly evaluate this application and to determine if its introduction can reduce invasive cancer rates. There is an urgent need to undertake a large trial of HPV testing in conjunction with other new technologies (liquid-based cytology and computer-assisted cytology reading) to determine the best way to integrate them into ongoing screening programmes. A range of issues including the age to start and stop screening, the appropriate screening interval, the role of self-sampling for HPV testing and the choice of primary test (HPV and/or cytology) require further evaluation.

Amplification with molecular beacon primers and reverse line blotting for the detection and typing of human papillomaviruses

A novel method for the detection and typing of human papillomavirus (HPV) was developed using molecular beacon primers. The method is based on the use of HPV-specific primers containing a hairpin loop structure in which fluorescent donor and quencher groups are held in close proximity such that fluorescence is quenched. Amplification of the target sequence results in the opening of the loop and the resulting fluorescence can be detected on a sequence detector system (SDS) 7700 (Applied Biosystems), as used for TaqMan assays. Fluorescent amplicons were identified on the SDS 7700 and then typed by a single hybridisation with specific probes immobilised in lines on a nylon membrane and detected on a fluorescent scanner. This novel beacon primer method compared well with conventional PCR for cervical scrape specimens. The combination of the beacon primer method and reverse line blotting should enable large-scale population studies of HPV infection.

The planning of cervical cancer screening programmes in eastern Europe: is viral testing a suitable alternative to smear testing?

Cervical cancer screening with human papillomavirus (HPV) DNA testing has potential advantages over conventional, smear testing in that it can predict cases in which invasive cancers are more likely to develop, may be cheaper to implement and improve compliance. In areas of the world where little formalized cervical cancer screening takes place, or where health resources are limited, HPV testing has been suggested as a possible alternative for primary screening. In this paper we demonstrate the use of mathematical modelling to evaluate the effects of setting up screening programmes in Eastern Europe with HPV DNA testing as the primary screening tool and compare it with conventional smear testing. The impact of screening is measured in terms of the life years gained and the resulting resource usage and cost. We investigate several screening options with different screening intervals and age ranges for the target population.

Evaluation of alternative methods of cervical cancer screening for resource-poor settings

BACKGROUND

Noncytologic methods of screening for cervical carcinoma and its precursor lesions are needed for resource-poor settings in which cervical carcinoma continues to be an important cause of morbidity and mortality.

METHODS

Two thousand nine hundred forty-four women ages 35-65 years were recruited from Cape Town, South Africa and screened using a combination of a Papanicolaou (Pap) smear, human papillomavirus (HPV) DNA testing, direct visual inspection after the application of a 5% acetic acid solution (DVI), and cervicography. Cervicography was considered primarily as a method with which to quality control the DVI examinations. Women with squamous intraepithelial lesions (SIL) or carcinoma on Pap smear, positive DVI examination (acetowhite lesion or cervical ulcer/growth), high levels of high risk HPV DNA (relative light units [RLU] > 10x positive control), or positive Cervigramtrade mark were referred for colposcopy and cervical biopsy.

RESULTS

Pap smears were positive in 8.1% of all women screened and identified 65 (78%) of all cases of biopsy confirmed high grade disease (high grade SIL or invasive carcinoma). DVI and cervicography were classified as positive in 18.1% and 10.5%, respectively, of women screened and identified 58 (67%) and 46 (58%) of all cases of high grade disease, respectively. The results of HPV DNA testing varied depending on the cutoff value used to define a positive result. At the standard cutoff level (RLU > 1x positive control), 16.2% of women screened were classified as high risk HPV DNA positive, as were 63 women with high grade disease (73%).

CONCLUSIONS

DVI and HPV DNA testing identified similar numbers of high grade SIL (cervical intraepithelial neoplasia Grade 2,3) and invasive carcinoma cases as Pap smears. However, both classify considerably more women without cervical disease as being test positive.

Update on cancer control in women

The global cancer burden in women appears to have stabilized according to the most recent estimates available although the distribution of cancer types appears to be changing with a sharp contrast between the increase in the absolute numbers of breast cancers and a decline in cervix cancers. Prospects for cancer control in women appear to be good within our current knowledge and deserve close attention. Rates of lung cancer in women are increasing substantially in many countries and seem set to overtake breast cancer as the commonest form of cancer death in women in many parts of the world. These changes are due to the effects of cigarette smoking, a habit which women widely embraced during the second half of the last century. The high levels of smoking currently in young women, which have yet to have their full impact on death rates, constitute an important hazard not only for future cancer risks but for several other important causes of death. There is strong and consistent evidence that increased consumption levels of fruit and vegetables is associated with reduced risks of many common forms of cancer including breast cancer. Although the breast is the commonest form of cancer in women in most western countries, the etiology of this disease remains elusive and preventable causes remain to be identified. Endogenous hormones also appear to have a role in cancer risk in women: oral contraceptives seem to increase slightly the risk of breast cancer in users in the use and in the immediate post-use period, but 10 years after cessation the risk again returns to that of never users. Oral contraceptive usage also appears to be protective against ovarian and endometrial cancer. The use of hormonal replacement therapy (HRT) appears to increase the risk of endometrial cancer and a positive association with breast cancer risk appears to exist. Within our current knowledge of the epidemiology of cancer in women, the most important preventive strategies would appear to be the prevention of cigarette smoking and increased dietary intake of vegetables and fruits. Screening has also shown to be effective in reducing incidence and mortality of cervix cancer and mortality from breast cancer. Although more work is needed, it is becoming clear that there could be an important role of HPV testing to further enhance cervix cancer screening. There are important variations in survival from a variety of cancers which are due to factors unrelated to the tumor behavior and that there are significant variations in survival from cancer. Reduction of these gaps could lead to a reduction in cancer mortality and contribute towards increased prospects for cancer control in women.

PCR based high risk HPV testing is superior to neural network based screening for predicting incident CIN III in women with normal cytology and borderline changes

BACKGROUND/AIMS

To improve the accuracy of conventional cytology in cervical cancer screening, high risk human papillomavirus (HPV) testing and neural network based screening have been developed. This study assessed the power of both techniques to detect women at risk of developing incident CIN III; that is, CIN III detected during the follow up of women with normal cytology and borderline nuclear changes.

METHODS

A cohort of 2250 women, 34-54 years of age, who attended population based cervical cancer screening from 1988 to 1991 and had normal smears or borderline nuclear changes was followed. All smears were tested for high risk HPV and the smears were rescreened using neural network based screening. The value of neural network based screening for predicting incident CIN III during a mean follow up period of 6.4 years was compared with that of high risk HPV testing. In addition, morphological markers presumed to be related to HPV were correlated with HPV status.

RESULTS

Thirteen (0.6%) women had incident CIN III. Both high risk HPV positivity and abnormal cytology were associated with an increased risk for incident CIN III (odds ratio, 240 and 22, respectively) and high risk HPV positivity was associated with abnormal cytology. The sensitivity of high risk HPV testing for predicting incident CIN III was much higher than that of neural network based screening (92% and 46%, respectively). None of the morphological markers assessed, including koilocytosis, was correlated with high risk HPV status.

CONCLUSION

High risk HPV testing is superior to neural network based screening in identifying women at risk of developing CIN III. For women with normal cytology and borderline changes and a negative high risk HPV test, the screening interval can be considerably prolonged.

Genetic changes in solid tumors

Although most solid tumors are treated surgically, determining the genetic changes present in the tumor of an individual patient is becoming increasingly important for managing the oncology patient. Our knowledge of the genetic alterations that characterize and predispose to solid tumors continues to expand. Concurrently, the advent of newer technologies such as DNA chips has the potential to enable a more rapid and comprehensive assessment of these changes. The ultimate goal of this new information and technology is to provide sensitive and specific tests that reduce unnecessary procedures and optimize therapy. This review addresses the utility of molecular testing in evaluating cancer. A review of the current technology and hereditary cancer syndromes is also presented.

Photodetection of cervical intraepithelial neoplasia using 5-aminolevulinic acid-induced porphyrin fluorescence

BACKGROUND

Screening for cervical carcinoma and its precursors is based on cervical cytology and diagnostic colposcopy. Despite the decrease in the incidence of cervical carcinoma in countries with a good screening program, this rate of decline is leveling off. Known problems are false-negative rates of cytology and low specificity of colposcopy. This clinical study examined the diagnostic potential of porphyrin fluorescence in patients with cervical intraepithelial neoplasia Grade 1-3 (CIN 1-3).

METHODS

Sixty-eight women attending our colposcopy clinic underwent a gynecologic examination, including cytology, human papillomavirus (HPV) testing, and colposcopy. They received 10 mL 0.5% or 1.0% 5-aminolevulinic acid (5-ALA) topically. After 30-360 minutes, real-time image analysis was performed, and spectra were obtained from 685 sites.

RESULTS

Due to rapid photobleaching, 0.5% 5-ALA proved ineffective for fluorescence assessment. Using 1% 5-ALA, the authors found that fluorescence intensities correlated with incubation time; however, fluorescence contrast showed a maximum at 60-90 minutes (ratio 11:1). HPV DNA positive lesions showed significantly higher fluorescence. Fluorescence imaging after 60-90 minutes achieved similar sensitivity and specificity compared with colposcopy in detecting CIN with 94% and 51% versus 95% and 50%, respectively. However, the specificity was markedly improved by fluorescence spectroscopy, achieving 75%. The evaluation of spectral measurements revealed significantly higher values for CIN compared with normal tissue and for CIN 2/3 compared with CIN 1 (P < 0.001).

CONCLUSIONS

Using a time interval of 60-90 minutes after topical application of 1% 5-ALA, the authors observed specific porphyrin fluorescence of CIN. Fluorescence spectroscopy promises to become a valuable tool for the diagnosis of CIN.