Adjunctive colposcopy technologies for examination of the uterine cervix--DySIS, LuViva Advanced Cervical Scan and Niris Imaging System: a systematic review and economic evaluation

BACKGROUND

Women in England (aged 25-64 years) are invited for cervical screening every 3-5 years to assess for cervical intraepithelial neoplasia (CIN) or cancer. CIN is a term describing abnormal changes in the cells of the cervix, ranging from CIN1 to CIN3, which is precancerous. Colposcopy is used to visualise the cervix. Three adjunctive colposcopy technologies for examination of the cervix have been included in this assessment: Dynamic Spectral Imaging System (DySIS), the LuViva Advanced Cervical Scan and the Niris Imaging System.

OBJECTIVE

To determine the clinical effectiveness and cost-effectiveness of adjunctive colposcopy technologies for examination of the uterine cervix for patients referred for colposcopy through the NHS Cervical Screening Programme.

DATA SOURCES

Sixteen electronic databases [Allied and Complementary Medicine Database (AMED), BIOSIS Previews, Cochrane Database of Systematic Reviews (CDSR), Cochrane Central Register of Controlled Trials (CENTRAL), Cumulative Index to Nursing and Allied Health Literature (CINAHL), Database of Abstracts of Reviews of Effects (DARE), EMBASE, Health Management Information Consortium (HMIC), Health Technology Assessment (HTA) database; Inspec, Inside Conferences, MEDLINE, NHS Economic Evaluation Database (NHS EED), PASCAL, Science Citation Index Expanded (SCIE) and Science Citation Index (SCI) - Conference Proceedings], and two clinical trial registries [ClinicalTrials.gov and Current Controlled Trials (CCT)] were searched to September-October 2011.

REVIEW METHODS

Studies comparing DySIS, LuViva or Niris with conventional colposcopy were sought; a narrative synthesis was undertaken. A decision-analytic model was developed, which measured outcomes in terms of quality-adjusted life-years (QALYs) and costs were evaluated from the perspective of the NHS and Personal Social Services with a time horizon of 50 years.

RESULTS

Six studies were included: two studies of DySIS, one study of LuViva and three studies of Niris. The DySIS studies were well reported and had a low risk of bias; they found higher sensitivity with DySIS (both the DySISmap alone and in combination with colposcopy) than colposcopy alone for identifying CIN2+ disease, although specificity was lower with DySIS. The studies of LuViva and Niris were poorly reported and had limitations, which indicated that their results were subject to a high risk of bias; the results of these studies cannot be considered reliable. The base-case cost-effectiveness analysis suggests that both DySIS treatment options are less costly and more effective than colposcopy alone in the overall weighted population; these results were robust to the ranges tested in the sensitivity analysis. DySISmap alone was more costly and more effective in several of the referral groups but the incremental cost-effectiveness ratio (ICER) was never higher than £1687 per QALY. DySIS plus colposcopy was less costly and more effective in all reasons for referral. Only indicative analyses were carried out on Niris and LuViva and no conclusions could be made on their cost-effectiveness.

LIMITATIONS

The assessment is limited by the available evidence on the new technologies, natural history of the disease area and current treatment patterns.

CONCLUSIONS

DySIS, particularly in combination with colposcopy, has higher sensitivity than colposcopy alone. There is no reliable evidence on the clinical effectiveness of LuViva and Niris. DySIS plus colposcopy appears to be less costly and more effective than both the DySISmap alone and colposcopy alone; these results were robust to the sensitivity analyses undertaken. Given the lack of reliable evidence on LuViva and Niris, no conclusions on their potential cost-effectiveness can be drawn. There is some uncertainty about how generalisable these findings will be to the population of women referred for colposcopy in the future, owing to the introduction of the human papillomavirus (HPV) triage test and uptake of the HPV vaccine.

Flavopiridol (L86 8275; NSC 649890), a new kinase inhibitor for tumor therapy

Flavopiridol is a new synthetic flavone, structurally related to a natural alkaloid, originally purified from Dysoxylum binectariferum, a plant indigenous to India and used in Indian folk medicine. Flavopiridol was detected by a tandem screening system consisting in inhibition of the EGF-receptor Tyrosine phosphokinase and cytotoxicity. As a cytostatic mechanism, however, Flavopiridol strongly inhibits the cyclin-dependent kinases (cdk1, cdk2, cdk4, cdk7), with the potential to cause inhibition of cell cycle progression in G(1) and G(2) by multiple mechanisms relatable to cdk inhibition. In certain cell types, Flavopiridol induces apoptosis. The antitumor activity of that compound on human xenograft tumors is similar to standard cytostatic drugs and superior to them at least in prostate carcinoma. The dose limiting toxicity is diarrhea. Compared with other flavonoids or other kinase inhibitors Flavopiridol can be regarded as unique as no other compound is yet known that as specifically and potently inhibits nearly all the main cyclin dependent kinases and by that mechanisms can arrest cell cycle progression in G(1) as well as in G(2) and no other specific kinase inhibitor is known, which after i.v. or oral application reduces the growth of subcutaneous or subrenal xenografts of human tumors of different types. Initial results of a phase I study at the National Cancer Institute (NCI), USA, (Investigational New Drug Application no. 46211) provided some clinical and laboratory evidence for antineoplastic effect at nontoxic doses (no grade IV toxicities encountered). Thus, Flavopiridol is clearly in need of further clinical evaluation of its tumor therapeutic potential. In this review the chemical profile, tumorpharmacology (in vitro activity, inhibition of cdk's and preclinical in vivo activity), preclinical toxicology and pharmacokinetic of Flavopiridol are reviewed to provide a comprehensive source to aid further developmental efforts.

Tumour-free distance from serosa is a better prognostic indicator than depth of invasion and percentage myometrial invasion in endometrioid endometrial cancer

OBJECTIVE

To evaluate the prognostic performance of tumour-free distance (TFD) compared with depth of invasion (DOI) and percentage of myometrial invasion (MI).

DESIGN

Retrospective cohort study.

SETTING

Regional gynaecological oncology centre.

POPULATION

All women identified with stage I-III endometrioid endometrial carcinoma from January 2000 to December 2007, who had surgery at the Northern Gynaecological Oncology Centre (NGOC).

METHODS

Surgicopathological, follow-up and survival data were collected. Univariate and multivariate analyses were performed comparing TFD, DOI and MI with known prognostic factors. The prognostic accuracy of TFD was assessed by receiver operating characteristic (ROC) curve analyses, and an optimum cut-off was proposed.

MAIN OUTCOME MEASURES

Death from disease, recurrence and pelvic lymph node involvement.

RESULTS

A total of 288 women were identified. The median follow-up time was 67 months, with 40 recurrences and 32 disease-related deaths. When TFD, DOI and MI were separately examined in multivariate analyses with other covariates, TFD was an independent predictor of death from disease (HR 1.22; 95% CI 1.00-1.48; P = 0.05). In multivariate analyses including all three measures together (TFD, DOI and MI), TFD was an independent predictor of death from disease (HR 1.49; 95% CI 1.03-2.16; P = 0.04) and recurrence (HR 1.39; 95% CI 1.01-1.91; P = 0.05). TFD was also an independent predictor of lymph node involvement when examined separately (OR 0.74; 95% CI 0.56-0.96; P = 0.03), and together with DOI and MI (OR 0.67; 95% CI 0.49-0.92; P = 0.01), in women who had pelvic lymphadenectomy (n = 86). A TFD cut-off of 1.75 mm showed good prognostic performance.

CONCLUSIONS

The TFD measure may be a more accurate method of representing myometrial invasion in the staging for endometrial cancer.

Cervical cancer incidence in young women: a historical and geographic controlled UK regional population study

Background:

The commencing age of cervical screening in England was raised from 20 to 25 years in 2004. Cervical cancer incidence in young women of England is increasing. It is not clear if this is due to either greater exposure to population risk factors or reduced cervical screening.

Methods:

We measured if the relative risk of cervical cancer in younger women (20–29 years) of the north-east of England (NE) differed to that of women aged 30yrs and above since 2004. We also measured average annual percentage change (AAPC) in the 3 yr moving average incidence for all age-groups. Regional screening coverage rate and population risk factors were reviewed. Comparisons were made with Wales where screening continues to commence from the age of 20 yrs.

Results:

Cervical cancer incidence in women aged 20–29 increased annually by an average of 10.3% between 2000 and 2009. The rise in women aged 30–39 was less steep (3.5%/year) but no significant rise was observed in women aged 40–49. Socioeconomic factors remained stable or improved during the time period except for the incidence of chlamydia, herpes simplex and in particular, genital warts, which increased significantly in young women. Data from Wales show similar results.

Conclusion:

The incidence of cervical cancers in young women of the NE is increasing. The rise in incidence is unrelated to the change in screening policy in 2004. Close monitoring of incidence in young women and a greater attempt to reverse the current decline in screening coverage of women aged 25–29 years are recommended.

Borderline nuclear change, high-grade dyskaryosis not excluded: current concepts and impact on clinical practice

OBJECTIVE

Borderline nuclear change, high-grade dyskaryosis not excluded (B/HG) is a subcategory of the borderline category recommended by the British Society for Clinical Cytology as warranting direct referral to colposcopy. This subcategory is equivalent to the Bethesda category of atypical squamous cells, cannot exclude high-grade squamous intraepithelial lesion (ASC-H). The purpose of this study was to determine the validity and accuracy of using B/HG to identify potential cervical intraepithelial neoplasia (CIN) grade 2 or worse (CIN2+).

METHODS

Data were collected from the hospital pathology database for borderline, B/HG and high-grade cytology (moderate dyskaryosis and above), and their respective histological and colposcopic outcomes. SPSS was used for data analysis.

RESULTS

Of the 84,799 total cytology samples screened between July 2006 and December 2009, 5225 (6.1%) were reported as borderline, 309 (0.4%) as B/HG and 1222 (1.4%) as high-grade cytology. Thus, B/HG comprised 5.9% of the overall borderline category, in keeping with national guidelines (<10%). CIN2+ was confirmed in 86.6% of high-grade, 40.8% of B/HG and 3.0% of borderline cytology. Of 309 women reported with B/HG cytology, 239 had colposcopy. Colposcopic appearances showed a positive predictive value (PPV) of 71.8% for detecting CIN2+ and a negative predictive value of 60.7%.

CONCLUSIONS

The B/HG category was associated with a significantly higher incidence of CIN2+ compared with borderline cytology as a whole. This refining performance justifies its existence. Colposcopic appearances had a high PPV for detecting CIN2+. Therefore, colposcopy is recommended in patients with B/HG cytology and treatment should be offered if high-grade colposcopic changes are seen.

Intra-operative frozen section analysis for suspected early-stage ovarian cancer: 11 years of Gateshead Cancer Centre experience

OBJECTIVE

In centres in which intra-operative frozen section (FS) analysis is not performed, 'apparent' early-stage ovarian cancer diagnosed after surgery on paraffin section may require further restaging laparotomy or adjuvant chemotherapy. Previous studies on FS analysis have reported high sensitivity, specificity and overall accuracy. The objective of this article is to present the largest published dataset on the accuracy of FS analysis over an 11-year period from a single institution.

DESIGN

Diagnostic test accuracy.

SETTING

Northern Gynaecological Oncology Centre and Department of Cellular Pathology, Gateshead, UK.

POPULATION

1439 intra-operative FS analyses performed between January 2000 and December 2010 for suspected ovarian cancer.

METHODS

Prospectively collected data on FS analysis were compared with gold standard paraffin section.

MAIN OUTCOME MEASURES

Sensitivity, specificity, likelihood ratios and post-test probability.

RESULTS

The overall sensitivity and specificity of FS analysis were 91.2% and 98.6%, respectively. Positive and negative likelihood ratios were 64.7% and 0.09%, respectively. The pre-test probability of an ovarian tumour being borderline or malignant was 45.8%. When FS analysis was reported to be positive, the post-test probability increased to 98% (confidence interval, 97-99%). Conversely, when FS analysis was reported to be negative, the post-test probability decreased to 7% (confidence interval, 6-9%). The majority of false test results were either borderline tumours or of mucinous differentiation.

CONCLUSIONS

Intra-operative FS analysis has excellent diagnostic test accuracy and assists gynaecological oncologists to perform the appropriate surgery in 95% of cases, thereby preventing the morbidity of surgical staging in benign cases and the morbidity of restaging procedures or chemotherapy in early-stage malignant tumours.

Histological recurrence and depth of loop treatment of the cervix in women of reproductive age: incomplete excision versus adverse pregnancy outcome

OBJECTIVE

Recent meta-analyses have shown that loop treatment of the cervix of > 10 mm depth may be associated with adverse outcomes in future pregnancies. The aim of this study is to assess the rate of incomplete excision and recurrent disease in relation to depth of excision in women of reproductive age undergoing loop treatment.

DESIGN

Observational cohort study.

SETTING

Colposcopy Clinic, Northern Gynaecological Oncology Centre, Gateshead, UK.

POPULATION

In all, 1558 women undergoing loop treatment for high-grade cervical intraepithelial neoplasia (HGCIN) between 1998 and 2003.

METHODS

Women were followed up until 2008. Recurrence was analysed using Kaplan-Meier plots.

OUTCOME MEASURES

Incomplete excision rates and recurrence rates. Recurrence was defined as post-treatment disease with high-grade histology. Any dyskaryotic cytology on follow-up was also documented.

RESULTS

Recurrent high-grade disease on histology was found in 57/1558 (3.7%) women. In women ≤ 35 years old, despite a greater rate of incomplete excision at the endocervical margin at loop depths < 10 mm compared with ≥ 10 mm (24.4% versus 13.3%, P < 0.01), the recurrence rate was similar between the two groups (4.3% versus 3.4%, log-rank, P = 0.52). In contrast, a loop depth < 10 mm was associated with a higher disease recurrence rate (7.5% versus 3.0%, log-rank, P = 0.05) in women > 35 years.

CONCLUSION

In women of reproductive age requiring treatment for HGCIN, colposcopists performing loop excision should aim for < 10 mm depth. This provides adequate treatment for HGCIN and minimises the potential risk of adverse outcomes in future pregnancies.

Optical and Electrical Properties of Al1−xInxN Films Grown on Sapphire (0001) by Plasma Source Molecular Beam Epitaxy

A series of epitaxial InxAl1−xN alloy films (thickness ~ 150 nm) with 0 ≤ × ≤ 1.0 were grown by Plasma Source Molecular Beam Epitaxy (PSMBE) on sapphire (0001) at a low substrate temperature of 375 °C. X-ray diffraction (XRD) measurements confirm a c-axis oriented epitaxial growth of alloy films without any alloy segregation. However, the degree of crystalline mosaicity, compositional fluctuation and surface roughness, all increase with increasing x. The direct energy band gap of alloy films were determined using optical (UV-VIS) transmission and reflection measurements. The observed bowing of the direct gap versus x plot, when compared to the theoretical prediction, is less pronounced than seen in earlier studies reported in literature. Electrical resistivity and Hall effect measurements show n-type electrical conductivity in these alloys with carrier concentrations ~1019-1020 cm−3 for x > 0.5.

Optical Properties of Anatase, Rutile and Amorphous Phases of TiO2 Thin Films Grown at Room Temperature by RF Magnetron Sputtering

Anatase (A), rutile (R) and amorphous phase TiO2 thin films have been prepared by RF magnetron sputtering on unheated glass substrates by controlling the total pressure of sputtering gases (Ar + O2) and the substrate bias. The crystal structures of the films were confirmed by x-ray diffraction and Raman scattering. The analysis of optical absorption data for A- TiO2 film shows an energy bandgap (Eg) of 3.2 eV (indirect extrapolation) and ∼ 3.5 eV (direct extrapolation). On the other hand, R-TiO2 film shows Eg ∼ 2.9 eV (indirect) and 3.2 eV (direct). The latter film also shows the presence of amorphous regions with Eg ∼ 3.0 eV (indirect) and 3.8 eV (direct). The bandgap of both the films, obtained using indirect extrapolation, has a value range consistent with the previous measurements.