James Bentley

Aptima HPV E6/E7 mRNA Test Is as Sensitive as Hybrid Capture 2 Assay but More Specific at Detecting Cervical Precancer and Cancer

ABSTRACT Detection of human papillomavirus (HPV) E6/E7 oncogene expression may be more predictive of cervical cancer risk than testing for HPV DNA. The Aptima HPV test (Gen-Probe) detects E6/E7 mRNA of 14 oncogenic types. Its clinical performance was compared with that of the Hybrid Capture 2 DNA test (HC2; Qiagen) in women referred for colposcopy and those routinely screened. Aptima was also compared with the PreTect HPV-Proofer E6/E7 mRNA assay (Proofer; Norchip) in the referral population. Cervical specimens collected in PreservCyt (Hologic Inc.) were processed for HPV detection and genotyping with the Linear Array (LA) method (Roche Molecular Diagnostics, Laval, Quebec, Canada). Histology-confirmed high-grade cervical intraepithelial neoplasia (CIN 2) or worse (CIN 2+) served as the disease endpoint. On the basis of 1,418 referral cases (CIN 2+, n = 401), the sensitivity of Aptima was 96.3% (95% confidence interval [CI], 94.4, 98.2), whereas it was 94.3% (95% CI, 92.0, 96.6) for HC2. The specificities were 43.2% (95% CI, 40.2, 46.2) and 38.7% (95% CI, 35.7, 41.7), respectively (P < 0.05). In 1,373 women undergoing routine screening (CIN 2+, n = 7), both Aptima and HC2 showed 100% sensitivity, and the specificities were 88.3% (95% CI, 86.6, 90.0) and 85.3% (95% CI, 83.5, 87.3), respectively (P < 0.05); for women ≥30 years of age (n = 845), the specificities were 93.9% (95% CI, 92.3, 95.5) and 92.1% (95% CI, 90.3, 93.9), respectively (P < 0.05). On the basis of 818 referral cases (CIN 2+, n = 235), the sensitivity of Aptima was 94.9% (95% CI, 92.1, 97.7) and that of Proofer was 79.1% (95% CI, 73.9, 84.3), and the specificities were 45.8% (95% CI, 41.8, 49.8) and 75.1% (95% CI, 71.6, 78.6), respectively (P < 0.05). Both Aptima and Proofer showed a higher degree of agreement with LA genotyping than HC2. In conclusion, the Aptima test is as sensitive as HC2 but more specific for detecting CIN 2+ and can serve as a reliable test for both primary cervical cancer screening and the triage of borderline cytological abnormalities.

Clinical Performance of the PreTect HPV-Proofer E6/E7 mRNA Assay in Comparison with That of the Hybrid Capture 2 Test for Identification of Women at Risk of Cervical Cancer

ABSTRACT Human papillomavirus (HPV) DNA testing has a higher clinical sensitivity than cytology for the detection of high-grade cervical intraepithelial neoplasia or worse (CIN 2+). However, an improvement in specificity would be desirable. As malignant transformation is induced by HPV E6/E7 oncogenes, detection of E6/E7 oncogene activity may improve specificity and be more predictive of cervical cancer risk. The PreTect HPV-Proofer assay (Proofer; Norchip) detects E6/E7 mRNA transcripts from HPV types 16, 18, 31, 33, and 45 with simultaneous genotype-specific identification. The clinical performance of this assay was assessed in a cross-sectional study of women referred for colposcopy in comparison with the Hybrid Capture 2 (HC2; Qiagen) test, which detects DNA of 13 high-risk oncogenic HPV types collectively. Cervical specimens were collected in PreservCyt, and cytology was performed using the ThinPrep method (Hologic). The samples were processed for HPV detection with Proofer and HC2 and genotyping with the Linear Array method (Roche Molecular Systems). Histology-confirmed CIN 2+ served as the disease endpoint to assess the clinical performance of the tests. A total of 1,551 women were studied, and of these, 402 (25.9%) were diagnosed with CIN 2+ on histology. The Proofer assay showed a sensitivity of 78.1% (95% confidence interval [CI], 74.1 to 82.1) versus 95.8% (95% CI, 93.8 to 97.8) for HC2 (P < 0.05) and a specificity of 75.5% (95% CI, 73.0 to 78.0) versus 39.6% (95% CI, 36.8 to 42.4), respectively (P < 0.05). The lower sensitivity and higher specificity of Proofer for detection of CIN 2+ can be attributed to the fact that this test detects the expression of E6/E7 genes beyond a threshold from a limited number of oncogenic HPV types. In conclusion, Proofer is more specific than HC2 in identifying women with CIN 2+ but has a lower sensitivity.

Optimization of primary and secondary cervical cancer prevention strategies in an era of cervical cancer vaccination: A multi-regional health economic analysis

With the recent advent of cervical cancer vaccines, many questions relating to the best overall prevention methods for cervical disease are beginning to arise. A Markov model was used across five geographic regions (Canada, The Netherlands, Taiwan, UK, US) to examine the clinical benefits and cost-effectiveness of: (1) vaccination combined with screening, considering changes to screening-related parameters and (2) vaccination combined with screening, considering changes to screening policy. Given the assumptions used in this analysis, adding vaccination to current screening is likely to be cost-effective in the regions studied. When considering vaccination with several plausible changes to screening programmes, locations with the most frequent Papanicolaou smear testing may achieve the most efficiency gains by adopting a less frequent screening interval or incorporating HPV testing into their screening practices. Although it may be beneficial to change screening to maximize efficiency, the most cost-effective strategies for vaccination and screening combinations may not lead to the greatest reductions in cervical cancer; therefore such policy decisions may vary depending on region-specific goals. Finally, new screening paradigms such as primary HPV testing should be considered in future analyses.

Distribution of human papillomavirus genotypes in cervical intraepithelial neoplasia and invasive cervical cancer in Canada

Infection with high‐risk human papillomavirus (HPV) causes cervical intraepithelial neoplasia (CIN) and invasive cervical cancer (ICC). The distribution of HPV types in cervical diseases has been previously described in small studies for Canadian women. The prevalence of 36 HPV genotypes in 873 women with CIN and 252 women with ICC was assessed on cervical exfoliated cells analyzed with the Linear Array (Roche Molecular System). HPV16 was the most common genotype in CIN and ICC. The seven most frequent genotypes in order of decreasing frequency were HPV16, 51, 52, 31, 39, 18, and 56 in women with CIN1, HPV16, 52, 31, 18, 51, 39, and 33 in women with CIN2, HPV16, 31, 18, 52, 39, 33, and 58 in women with CIN3, and HPV16, 18, 45, 33, 31, 39, and 53 in women with ICC. HPV18 was detected more frequently in adenocarcinoma than squamous cell carcinoma (Pu2009=u20090.013). Adjustment for multiple type infections resulted in a lower percentage attribution in CIN of HPV types other than 16 or 18. The proportion of samples containing at least one oncogenic type was greater in CIN2 (98.4%) or CIN3 (100%) than in CIN1 (80.1%; Pu2009<u20090.001 for each comparison). Multiple type infections were demonstrated in 51 (20.2%) of 252 ICC in contrast to 146 (61.3%) of 238 women with CIN3 (Pu2009<u20090.001). Adjusting for multiple HPV types, HPV16 accounted for 52.1% and HPV18 for 18.1% of ICCs, for a total of 70.2%. Current HPV vaccines should protect against HPV types responsible for 70% of ICCs in Canadian women. J. Med. Virol. 83:1034–1041, 2011.

Maternal age-related rates of gestational trophoblastic disease.

OBJECTIVE: To estimate the incidence of gestational trophoblastic disease in Nova Scotia and to evaluate the effect of time and maternal age on these rates. METHODS: Information on women with a pathologically confirmed diagnosis of gestational trophoblastic disease was extracted from the Nova Scotia Gestational Trophoblastic Disease Registry between 1990 and 2005. The total numbers of deliveries and pregnancies were determined from the Nova Scotia Atlee Perinatal Database and consensus data derived from Statistics Canada. RESULTS: Four-hundred twenty-eight women were identified with gestational trophoblastic disease. Hydatidiform moles showed rates of 220/100,000 pregnancies, 264/100,000 total births, and 266/100,000 live births. Rates of partial mole were twofold higher than complete mole (P<.001). The rates of hydatidiform mole were highest in both younger (younger than 20 years old, P=.02) and older age groups (30–34 years old, P=.04, and at least 35 years old, P=.02). The rates of hydatidiform mole were highest in both younger (less than 20 years old, P=.02) and older age groups (30–34 years old, P .04, and 35 or more years old P=.02). The rates of partial moles were significantly higher in women older than 20 years of age (P<.001) and increased with increasing age (P<.001); the reverse trend was seen in complete mole (P<.001). There was no temporal change in rates or average age of hydatidiform mole during the study period. CONCLUSION: The rates of hydatidiform mole in Nova Scotia estimated by this population-based study using comprehensive validated information, are higher than most previously reported. Maternal age was a significant factor in the risk for molar pregnancies. LEVEL OF EVIDENCE: II

Initial Evaluation and Referral Guidelines for Management of Pelvic/Ovarian Masses

OBJECTIVESnTo optimize the management of adnexal masses and to assist primary care physicians and gynaecologists determine which patients presenting with an ovarian mass with a significant risk of malignancy should be considered for gynaecologic oncology referral and management.nnnOPTIONSnLaparoscopic evaluation, comprehensive surgical staging for early ovarian cancer, or tumour debulking for advanced stage ovarian cancer.nnnOUTCOMESnTo optimize conservative versus operative management of women with possible ovarian malignancy and to optimize the involvement of gynaecologic oncologists in planning and delivery of treatment.nnnEVIDENCEnPublished literature was retrieved through searches of PubMed or MEDLINE, CINAHL, and the Cochrane Library, using appropriate controlled vocabulary and key words. Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies. Grey (unpublished) literature was identified by searching the web sites of health technology assessment and health technology assessment-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies.nnnRECOMMENDATIONSn1. Primary care physicians and gynaecologists should always consider the possibility of an underlying ovarian cancer in patients in any age group who present with an adnexal or ovarian mass. (II-2B) 2. Appropriate workup of a perimenopausal or postmenopausal woman presenting with an adnexal mass should include evaluation of symptoms and signs suggestive of malignancy, such as persistent pelvic/abdominal pain, urinary urgency/frequency, increased abdominal size/bloating, and difficulty eating. In addition, CA125 measurement should be considered. (II-2B) 3. Transvaginal or transabdominal ultrasound examination is recommended as part of the initial workup of a complex adnexal/ovarian mass. (II-2B) 4. Ultrasound reports should be standardized to include size and unilateral/bilateral location of the adnexal mass and its possible origin, thickness of septations, presence of excrescences and internal solid components, vascular flow distribution pattern, and presence or absence of ascites. This information is essential for calculating the risk of malignancy index II score to identify pelvic mass with high malignant potential. (IIIC) 5. Patients deemed to have a high risk of an underlying malignancy should be reviewed in consultation with a gynaecologic oncologist for assessment and optimal surgical management. (II-2B).

Risk of Malignancy Index in the Evaluation of Patients With Adnexal Masses

OBJECTIVEnTo determine if the risk of malignancy index (RMI) can distinguish between benign and malignant adnexal masses in a population of women referred to a department of gynaecologic oncology for surgical resection of an adnexal mass.nnnMETHODSnWe performed a retrospective review of the medical of charts of 259 consecutive patients. Ninety-six charts did not have data available to calculate the RMI, leaving a total of 163 for review. Three definitions of RMI were compared; each incorporated menopausal status of the patient, ultrasound characteristics of the adnexal mass, and serum CA-125 level.nnnRESULTSnOf the masses resected, 105 were benign and 58 were malignant. The area under the ROC curve for all three definitions of RMI was 0.87. Using a cut-off of 120, the first RMI definition (RMI 1) had a sensitivity of 72% and a specificity of 87%; the second (RMI 2) had a sensitivity of 76% and a specificity of 81%; and the third (RMI 3) had a sensitivity of 74% and a specificity of 84%. These results are generally in agreement with published values.nnnCONCLUSIONnWe have validated the use of RMI to predict the risk of malignancy in a Nova Scotia population of women with adnexal masses. This will aid in more selective referral of patients to specialized oncology centres for cancer surgery, allowing for appropriate management of health care resources and optimization of treatment for women with gynaecological malignancies.

Introduction of molecular HPV testing as the primary technology in cervical cancer screening: Acting on evidence to change the current paradigm

Since being introduced in the 1940s, cervical cytology - despite its limitations - has had unequivocal success in reducing cervical cancer burden in many countries. However, we now know that infection with human papillomavirus (HPV) is a necessary cause of cervical cancer and there is overwhelming evidence from large-scale clinical trials, feasibility studies and real-world experience that supports the introduction of molecular testing for HPV as the primary technology in cervical cancer screening (i.e., HPV primary screening). While questions remain about the most appropriate age groups for screening, screening interval and triage approach, these should not be considered barriers to implementation. Many countries are in various stages of adopting HPV primary screening, whereas others have not taken any major steps towards introduction of this approach. As a group of clinical experts and researchers in cervical cancer prevention from across Canada, we have jointly authored this comprehensive examination of the evidence to implement HPV primary screening. Our intention is to create a common understanding among policy makers, agencies, clinicians, researchers and other stakeholders about the evidence concerning HPV primary screening to catalyze the adoption of this improved approach to cervical cancer prevention. With the first cohort of vaccinated girls now turning 21, the age when routine screening typically begins, there is increased urgency to introduce HPV primary screening, whose performance may be less adversely affected compared with cervical cytology as a consequence of reduced lesion prevalence post-vaccination.

Approaches for triaging women who test positive for human papillomavirus in cervical cancer screening

Substantial evidence exists to support the introduction of molecular testing for human papillomavirus (HPV) as the primary technology in cervical cancer screening. While HPV testing is much more sensitive than cytology for detection of high-grade precancerous lesions, it is less specific. To improve efficiency, it is therefore recommended that a specific test (like cytology) be used in triaging HPV positive women to colposcopy. A number of studies have been conducted that support the use of cytology alone or in conjunction with HPV genotyping for triage. The decision to incorporate genotyping also depends on the commercial HPV test that is selected since not all tests provide results for certain individual high-risk types. Regardless of whether policy officials decide to adopt a triage approach that incorporates genotyping, the use of liquid based cytology (LBC) may also improve screening performance by reducing diagnostic delays. With LBC, the same cell suspension from a single collection may be used for HPV testing and a smear can be immediately prepared if HPV status is positive. This was a critical lesson from a community based demonstration project in Montreal (VASCAR study), where conventional cytology exists and specimen co-collection was not permitted for ethical reasons, requiring HPV positive women to return for an additional screening visit prior to colposcopy.

Performance of ProEx C and PreTect HPV-Proofer E6/E7 mRNA tests in comparison with the hybrid capture 2 HPV DNA test for triaging ASCUS and LSIL cytology.

The clinical usefulness of the ProEx C (Becton Dickinson) and PreTect HPV‐Proofer E6/E7 mRNA tests (Proofer; Norchip) for the triage of ASCUS and LSIL cytology was determined in comparison with the Hybrid Capture 2 HPV DNA test (HC2; Qiagen). The study population consisted of women with a history of abnormal cytology referred to colposcopy. Histology‐confirmed CIN 2+ served as the disease endpoint. The study was based on 1,360 women (mean age 30.7 years), of whom 380 had CIN 2+. Among 315 with ASCUS (CIN 2+, n = 67), the sensitivities of ProEx C, Proofer, and HC2 to detect CIN 2+ were, 71.6, 71.6, and 95.5%, respectively, with a corresponding specificity of 74.6, 74.2, and 35.1%. Among 363 with LSIL (CIN 2+, n = 108), the sensitivities of ProEx C, Proofer, and HC2 were, 67.6, 74.1, and 96.3%, respectively, with a corresponding specificity of 60, 68.2, and 18.4%. Among 225 HC2‐positive ASCUS (CIN 2+, n = 64), 105 tested positive by ProEx C, reducing colposcopy referral by 53.3% and detecting 71.9% of CIN 2+; Proofer was positive in 112/225, reducing colposcopy referral by 50.2% and detecting 75.0% of CIN 2+. Among 312 HC2‐positive LSIL (CIN 2+, n = 104), 160 tested positive by ProEx C, reducing coloposcopy referral by 48.7% and detecting 66.3% of CIN 2+; Proofer was positive in 159/312, reducing colposcopy referral by 49.0% and detecting 75.0% of CIN 2+. In conclusion, both ProEx C and Proofer have a similar performance profile with a significantly higher specificity but lower sensitivity than HC2 for the detection of CIN 2+. Consequently, although they can reduce colposcopy referral, they will miss a proportion of CIN 2+ cases. This is a major limitation and should be taken into account if these tests are considered for ASCUS or LSIL triage. Diagn. Cytopathol. 2013;41:767–775.