New innovations in cervical cancer screening

[Quality of conventional PAP smears. Quality assessment and motivation for improvement]

The success of cytology in screening programs for cervical cancer is highly dependent on the smear quality. Interdisciplinary projects which evaluate the smear quality and the results of collection devices could be helpful for an improvement and a successful example for quality improvement is presented here. An average of 83% technically adequate and representative smears was documented for 12 million conventional PAP smears; however only an average of 68% technically adequate and representative smears was found for the group of least successful smear takers of all laboratories. This indicates a potential for improvement. Following an interdisciplinary project on smear quality improvement the average rate of representative smears increased from 69 to 83% and in another project this rate remained stable at 86%. Based on 158,411 conventional smears, representative smears were achieved in 92% using Cervex-Brush®, 86% using Szalay Spatula and 82% Cytobrush methods. The combinations of Cytobrush with the Ayre wooden spatula, cotton wool swab or Szalay Spatula achieved 97%, 94% and 92% representative smears, respectively.

Evaluation of visual inspection with acetic acid as a feasible screening test for cervical neoplasia

AIM

Alternative methods for cervical cancer screening have been sought. One method, direct visualization with acetic acid (VIA), has proven itself in many clinical trials as an adequate alternative to Pap-smears in developing countries. This study was designed to assess if visual inspection with acetic acid (VIA test) could be an appropriate alternative method for cervical cancer screening. Therefore, we compared VIA, as a stand-alone test, with the gold standard test (colposcopy) in detecting significant cervical pathology in our setting.

MATERIALS AND METHODS

The study population consisted of the women who attended the Gynecological Clinic in Ghaem Hospital from April 2008 to April 2009. All of them were tested with VIA. Then, 100 test-positive women and 100 test-negative women were randomly selected and underwent cytology and colposcopy. Cervical biopsies were conducted for the women with abnormal colposcopic findings. Sensitivity, specificity, positive predictive value and negative predictive value were calculated for each test and then were compared.

RESULTS

Sixty-nine women in the VIA-positive group and 61 women in the VIA-negative group had abnormal cytology. After studying the biopsies, 58 women with positive VIA, and two women with negative VIA had a final diagnosis of dysplasia. Positive predictive value for VIA and cytology were 58% and 33%, respectively.

CONCLUSION

The results of this study indicate that VIA may be a useful and feasible alternative screening test for cervical precancerous and cancerous lesions.

The current and future role of screening in the era of HPV vaccination

With the introduction of cervical screening programs, the incidence and mortality of cervical cancer has been drastically reduced. Techniques such as the traditional Papanicolaou test and the newer liquid-based cytology allow for the early detection of cervical abnormalities prior to the development of invasive cervical cancer. As oncogenic human papillomavirus (HPV) infection is necessary for cervical cancer, HPV-DNA testing has also been proposed as a routine screening method for the general population. Screening limitations, such as adherence, test sensitivity and specificity, access, and cost-effectiveness are reflected in current screening guidelines. The development of prophylactic cervical cancer vaccines is a major milestone in cervical cancer prevention. These vaccines protect against the initial infection of certain oncogenic HPV types, and therefore prevent the development of cervical dysplasia, precancerous lesions, and cervical cancer. Considering routine cervical cancer vaccination in adolescent girls, screening guidelines must adapt in order to retain efficient and cost-effective prevention measures. Although the true epidemiological and economic impact of cervical cancer vaccines cannot be immediately realized, mathematical models predict various scenarios in which vaccination, in addition to cervical screening, will be cost-effective and further reduce cervical cancer disease.

Taking a stand against cervical cancer

Help detect cervical cancer before it becomes difficult to treat. Here's how to encourage patients to get regular screening and to care for those with cancer.

Visual inspection with acetic acid as a feasible screening test for cervical neoplasia in Iran

The aim of this study was to estimate the sensitivity and specificity of visual inspection of the uterine cervix with acetic acid (VIA) as a screening test for cervical carcinoma and its precursors. One thousand and two hundred eligible women were screened by VIA and Papanicolaou smear. Those positive on one or both of these screening tests (n = 308) or those who had clinically suspicious lesions, even if the tests were negative [25% of remainders (n = 290)], were referred for colposcopy. Three hundred and fifty five of 598 women at colposcopy underwent biopsies or endocervical curettage. Those with cervical intraepithelial neoplasia I (CIN I) or worse lesions, diagnosed by histology, were considered true positive. VIA was positive in 191 women (16.1%). In 175 true-positive cases, VIA detected 130 cases, yielding a sensitivity of 74.3% and a specificity of 94%. By considering atypical squamous cell of undetermined significance or worse lesions on Papanicolaou smear as referring threshold for colposcopy, the sensitivity and specificity of cytology were 72 and 90.2%, respectively. In conclusion, the sensitivity and specificity of VIA is high and comparable with that of cytology. Hence, VIA can be undertaken as a feasible method of screening in cervical cancer in countries where access to cytopathology is limited.

Cervical biopsy-based comparison of a new liquid-based thin-layer preparation with conventional Pap smears

The objective of this study is to compare the diagnostic efficacy of universal collection medium (UCM) liquid-based cytology (LBC) (Digene Corp., MD) and the conventional Pap smear in a comparative study, using histologic results as the gold standard. This was a cross-sectional study. Conventional Pap smears and UCM LBC specimens, obtained from women in a low socioeconomic outpatient population referred to a tertiary center for gynecologic care, were compared. For the purpose of this study, when cervical specimens were collected for cytology, all women underwent colposcopy and biopsy was done if a cervical abnormality was observed. Cytologic evaluation of UCM LBC and conventional Pap smears were carried out separately, masked to the results of the other method. Agreement beyond chance between the two cytologic methods was ascertained by means of the unweighted kappa statistic. Sensitivity, specificity, and predictive values with 95% confidence intervals were calculated for both methods. McNemar's test was used to determine the level of association between the two cytology procedures. A total of 800 women were evaluated. Assessment of the overall agreement between the two cytologic methods yielded a kappa of 0.777 (P < 0.0001). After adjustment for histologic diagnosis, the computed kappa in each stratum was as follows: normal = 0.733; CIN 1 = 0.631; CIN 2/3 = 0.735; cancer = 0.652. The sensitivity and specificity of UCM LBC for detection of cervical intraepithelial lesions and cancer were 75.3% and 86.4%, respectively, not statistically different from the 81.8% and 85.2% seen with the conventional method. This study demonstrates that the UCM LBC method is as accurate as the conventional Pap smear cytology in detecting cervical intraepithelial lesions and cancer even so the UCM samples were systematically prepared from a second sampling of the cervix.

Photodynamic therapy of high-grade cervical intraepithelial neoplasia with 5-aminolevulinic acid

BACKGROUND AND OBJECTIVES

To determine the safety and efficacy of 5-aminolevulinic acid (ALA) as a topically applied photosensitizer for photodynamic therapy (PDT) of cervical intraepithelial neoplasia (CIN).

STUDY DESIGNS/MATERIALS AND METHODS

Forty women, who were at least 18 years old with persistent biopsy-proven CIN 2 and CIN 3 within the previous 3 months of enrollment, underwent PDT in a phase I and II design. Five escalating radiant energies (increments of 25 J/cm(2), beginning at 50-150 J/cm(2)) using a Coherent Dye Model 920 argon pumped dye laser providing light at 630 nm (maximum output 0.8 W) were used to perform PDT with a fixed dose of ALA (200 mg/ml). ALA was placed in a cervical cap fitted to the cervix. After 90 minutes, the cap was removed and the ectocervix was illuminated for 5-16 minutes, depending on the irradiance. Success was defined as the absence of CIN on Pap smear or colposcopic examination at 12-months. Patients were monitored for toxicity.

RESULTS

Thirty-two women (80%) completed the study with 1 year of follow-up. Sixty percent had CIN 3 and 40% CIN 2. Success rates at 4, 8, and 12 months were 51, 46, and 31%, respectively, and were not light-dose dependent. Three patients progressed from CIN 2 to CIN 3. Toxicity was tolerable and only consisted of spotting, vaginal discharge, mild cramping, and vaginal warmth. There was no apparent dose relationship to toxicity.

CONCLUSIONS

PDT at this light and ALA dose is well tolerated but has minimal activity in the treatment of CIN 2 and CIN 3. Other doses and schedules of light and ALA or novel photosensitizers may improve efficacy.