Human papillomavirus DNA testing for cervical cancer screening in low-resource settings.
(41/1426)
BACKGROUND: In many low-resource settings, there are barriers to cytologic screening for cervical cancer. This study evaluates human papillomavirus (HPV) DNA testing as an alternative screening method. METHODS: Cervical samples from 2944 previously unscreened South African women aged 35-65 years were tested for high-risk types of HPV with the use of the Hybrid Capture I (HCI) assay. Women also had a Pap smear, direct visual inspection of the cervix, and Cervicography(TM). Women positive on any screening test were referred for colposcopy. Samples from women with biopsy-confirmed, low-grade squamous intraepithelial lesions (SILs) (n = 95), high-grade SILs (n = 74), or invasive cervical cancer (n = 12) and a random sample of women with no cervical disease (n = 243) were retested for HPV DNA with the use of the more sensitive Hybrid Capture II (HCII) assay. All P values are two-sided. RESULTS: High-risk HPV DNA was detected in 73.3% and 88.4% of 86 women with high-grade SIL or invasive cancer and in 12.2% of 2680 and 18.1% of 243 women without evidence of cervical disease, with the use of the HCI and HCII assays, respectively. HPV DNA testing with the HCII assay was more sensitive than cytology for detecting high-grade SIL and invasive cancer (McNemar's test, P =.04), and testing with the HCI assay was of equivalent sensitivity (P =.61). Cytology had a statistically significantly better specificity (96.8%) than either the HCI assay (87.8%) or the HCII assay (81.9%) (P<.01). Receiver operating characteristic curves identified test cutoff values that allow HPV DNA testing to identify 57% of women with high-grade SIL or cancer, while classifying less than 5% of women with no cervical disease as HPV DNA positive. CONCLUSIONS: HPV DNA testing has a sensitivity equivalent to, or better than, that of cytology. Since HPV DNA testing programs may be easier to implement than cytologic screening, HPV testing should be considered for primary cervical cancer screening in low-resource settings. (+info)
Completeness of excision and follow up cytology in patients treated with loop excision biopsy.
(42/1426)
AIMS: To assess the relation between the grade and the status of follow up cytology, the completeness of loop excision biopsies with cervical intraepithelial neoplasia (CIN), and the findings at follow up cytology, as well as the differences between complete and incomplete exclusion, using the odds ratio. Treatment failure was assessed. METHODS: 1600 women with CIN (290 CIN1, 304 CIN2, 1006 CIN3) were followed for a minimum of six months and a maximum of 10 years. A database was created and comparisons performed. The mean age of the patients was 37 years. RESULTS: Excision was complete in over 84% of loops. Residual disease and recurrence of high grade dyskaryosis was more common in women with CIN 3 than CIN 2 or 1. No high grade dyskaryosis was seen in the fifth follow up smear in patients with CIN 1 and CIN 2. Residual, recurrent, and persistent disease was most common in patients with incompletely excised CIN at ectocervical and endocervical margins and deep margins of resection than in patients with completely excised CIN. The odds ratios were significantly higher in the women who had incomplete excision of CIN at ectocervical, endocervical, both ecto- and endocervical, and deep margins of resection compared with those with apparent complete excision of CIN lesions. One patient developed invasive squamous cell carcinoma 44 months after loop excision which showed CIN 3 invading endocervical crypts and extending to both ectocervical and endocervical margins of resection. CONCLUSIONS: At long term follow up, patients with CIN who have residual disease are at increased risk of persistent disease and should therefore be followed up regularly with cytology and colposcopy. The findings support national policy of returning women with treated CIN of any grade to normal recall after five years except for cases of CIN3 where excision was incomplete or equivocal. In these cases follow up with annual smear for 10 years is recommended. (+info)
Inverse relationship between the expression of the human papillomavirus type 16 transcription factor E2 and virus DNA copy number during the progression of cervical intraepithelial neoplasia.
(43/1426)
The human papillomavirus type 16 (HPV-16) status of 43 cervical biopsies, which had been characterized histologically as normal, various grades of cervical intraepithelial neoplasia (CIN) and invasive squamous cell carcinoma, was examined by using (i) a novel antibody against the HPV-16 E2 protein, (ii) sensitive HPV-16 DNA in situ hybridization and (iii) microdissection/PCR for the E2 ORF. The data indicate that E2 protein expression is highest in koilocytes in lower-grade CIN (I), but decreases with increasing grade, whereas the detection of HPV DNA is delayed until CIN I/II, rising to the highest levels in carcinoma cells. Co-localization of E2 with HPV-16 DNA-positive cells was most commonly observed in koilocytes in CIN II lesions. PCR analyses of microdissected epithelium from the same or serial sections indicated that E2 ORFs were retained in an intact form in a number of higher-grade CIN lesions and invasive carcinomas. (+info)
Clonality of precursors of cervical cancer and their genetical links to invasive cancer.
(44/1426)
Two problems were the focus of this study. (1) Is precancer and/or invasive cancer of the human cervix a poly- or monoclonal proliferation of neoplastic cells? (2) Are simultaneously present precancers and cancers of the cervix clonally related, or do they arise independently? Microdissection of 37 neoplastic lesions with different degrees of histologic severity in 22 patients followed by polymerase chain reaction-based analysis of X-chromosome inactivation was used as a principal method. Invasive cancers were interpreted as monoclonal because samples invariably showed monoclonal signals. In two thirds of these cases, simultaneously present precursors had the identical X-chromosome inactivation pattern, but in one third the pattern was different. Polyclonality was seen in a subgroup of precursors, where there was no simultaneous presence of invasive cancer. In contrast, when invasive cancer was present, no precursor signaled polyclonality. Data taken together indicate that the pathogenesis of cervical cancer is probably even more complicated than that of other cancers involving selection of subclones from originally polyclonal precursors and possibility of coexistence of precursors of different monoclonal composition. The study also observed that a large field of normal cervical squamous epithelium (approximately 500 basal squamous epithelial cells) with nonrandom X-chromosome inactivation was present. It remains to be further investigated whether this phenomenon represents an embryologic lyonization pattern of X-chromosome inactivation or postembryologic clonal expansion of submorphologically transformed cells. (+info)
Efficacy in treatment of subclinical cervical HPV infection without intraepithelial neoplasia: systematic review.
(45/1426)
CONTEXT: The treatment of the subclinical Human papillomavirus (HPV) infection of the uterine cervix is controversial. OBJECTIVE: To assess the efficacy of any therapy for subclinical HPV infection of the cervix without intraepithelial neoplasia, via a search in the medical literature. METHOD: We performed a systematic review with a comprehensive reference search in Medline, LILACS, Excerpta Medica, AIDSLINE, Popline, Cochrane Library and other authors' reference lists to identify experimental studies of therapy for subclinical HPV infection without intraepithelial neoplasia of the uterine cervix. In order to identify unpublished studies, we also contacted experts in the area, clinical trial registries, pharmaceutical industries, government and research institutions. We also searched on the Internet and in the book-of-abstracts of some medical conferences. The studies identified were masked and selected by inclusion criteria to help ascertain their internal validity. The data about regression or progression of HPV infection were extracted from the studies included. RESULTS: We identified 67 studies related to the treatment of subclinical HPV infection without intraepithelial neoplasia of the uterine cervix. Only five clinical trials matched the inclusion criteria and none demonstrated significant differences between the experimental group and the control group concerning regression of HPV infection (with or without CIN I) or progression to higher grades of CIN. CONCLUSION: The evidence we found in the medical literature regarding the efficacy of any therapy for subclinical HPV infection without intraepithelial neoplasia of the uterine cervix was unsatisfactory. (+info)
Cervical neoplasia and repeated positivity of human papillomavirus infection in human immunodeficiency virus-seropositive and -seronegative women.
(46/1426)
Increased risk for cervical intraepithelial neoplasia (CIN) in human immunodeficiency virus (HIV)-infected women may be explained by repeated positivity of human papillomavirus (HPV) infection facilitated by HIV infection and related immunosuppression. As part of a longitudinal study with semiannual examinations, 268 women in Baltimore, Maryland (of whom 184 were HIV+), provided 1,426 cervicovaginal lavage specimens tested for HPV DNA by a polymerase chain reaction-based assay between 1992 and 1998. HPV positivity and time to HPV clearance according to HIV serostatus and CD4+ cell count were compared using models for correlated binary data and survival analysis. Of the 187 participants who had at least one positive measurement, the probability of subsequent HPV positivity among HIV- women and HIV+ women with CD4+ > or =200 and <200 cells/microl was 47.5%, 78.7%, and 92.9% (p < 0.001). Within-women HPV results were correlated (i.e., clustered) in each group (p < 0.01). Compared with HIV-participants, the relative incidence of HPV clearance was 0.29 and 0.10 among HIV+ women with CD4+ > or =200 and <200 cells/microl (p < 0.001). At the end of follow-up, 11 women had biopsy-confirmed CIN. The association of HIV and CIN (p = 0.014) was fully explained by repeated HPV positivity induced by HIV infection (p = 0.648). Reversal of immunosuppression following potent antiretroviral therapy must be expected to have a dramatic impact on HIV-related CIN. (+info)
The borderline cervical smear: colposcopic and biopsy outcome.
(47/1426)
AIMS: To review the outcome of women referred with smears showing borderline nuclear change (BNC), and to determine any differences in outcome if BNC was persistent, preceded by dyskaryosis, or followed treatment for cervical intraepithelial neoplasia (CIN). In addition, to determine criteria that might permit delineation of a BNC subtype, predictive of CIN. METHODS: The records of 178 women referred for colposcopy in 1993, with last smear showing BNC, were obtained from our laboratory database. The cytology, colposcopy, and biopsy follow up for a five year period were also obtained. The patients were divided into three categories according to their smear status before the last referral borderline smear: category 1, persistent BNC (n = 39); category 2, BNC preceded by dyskaryotic smears (n = 100); and category 3, BNC after treatment for CIN (n = 39). The referral borderline smears were reviewed on cases with negative outcome and those with a biopsy diagnosis of CIN2 and CIN3. RESULTS: In 50 women (28%) no biopsy was deemed necessary after colposcopic assessment. The biopsy results in the remaining 128 (72%) women were as follows: normal in 18 (10%), koilocytosis in 12 (7%), CIN1 in 45 (25%), CIN2 in 32 (18%), and CIN3 in 21 (12%) women. High grade lesions (CIN2, CIN3) were seen on biopsy in 14 of 39, 33 of 100, and six of 39 cases in category 1, category 2, and category 3, respectively. Blind review of the referral borderline smears from 53 women with a biopsy diagnosis of high grade lesions (32 CIN2, 21 CIN3) confirmed they were borderline in 23, upgraded them to mild dyskaryosis in 15, and found that 14 cases of isolated moderate or severe dyskaryotic cells had been missed originally. The borderline change was in mature squamous cells in five of 23 and in immature metaplastic epithelium in 18 of 23 cases. After smear review in 68 women with negative outcome, 36 smears were reclassified as negative in keeping with inflammation and atrophy, three were considered unsatisfactory, one was upgraded to CIN1, and 28 were confirmed as BNC. Of the latter, 25 of 28 were in mature squamous cells. The five year follow up on women with negative colposcopy (n = 50), negative loop excision of transformation zone (LETZ) (n = 18), and LETZ with koilocytosis (n = 12) showed subsequent high grade CIN on LETZ in 16, 0, and two patients, respectively. CONCLUSIONS: On referral of women for colposcopy with last smear showing BNC, the outcome was high grade CIN in over 30% of cases, irrespective of whether the borderline smear was preceded by another borderline smear or by a dyskaryotic smear. In contrast, in those referred because of BNC after treatment of CIN, high grade CIN was seen less frequently (15% of cases). Furthermore, in cases that necessitated loop excisions, high grade CIN was seen in 41%. This study also showed that BNC associated with inflammation or atrophy, or BNC in mature squamous cells, appears to have lower predictive value for CIN than those cases where BNC is associated with immature metaplastic epithelium. The use of terms such as "BNC favour reactive" for the former and "BNC favour dyskaryosis" for the latter is recommended, together with follow up by cytology and colposcopy, respectively. (+info)
Uneven distribution of HPV 16 E6 prototype and variant (L83V) oncoprotein in cervical neoplastic lesions.
(48/1426)
A previous Swedish study revealed that both prototype and variant HPV16 E6 oncoprotein, occur in about equal numbers in high-grade cervical intraepithelial neoplasia (HCIN), whereas variant HPV16 predominates in invasive cervical squamous carcinoma. Most of the malignant HPV16 variants contain a common mutation, L83V, in the E6 oncoprotein. In the present investigation, 28 HPV16 positive, invasive cervical adenocarcinomas were collected from a total number of 131 adenocarcinomas. These HPV16-positive cases were evaluated with analysis of the E6 gene, using a recently described PCR-SSCP method for identification of the specific mutation (L83V) in the E6 gene. The results obtained were correlated to findings in 103 preinvasive, HCIN, and 31 invasive cervical squamous carcinomas also infected with HPV16. The HPV16 E6 variant L83V was present in 40% of the HCIN lesions, in 54% of the invasive adenocarcinomas, in comparison to 81% of the invasive squamous carcinomas. The difference between HCIN and squamous carcinomas was statistically significant, P < 0.001, whereas the difference between HCIN and invasive adenocarcinomas was not statistically significant, P = 0.604. Prototype HPV16 and its E6 variant L83V are both prevalent in preinvasive and invasive cervical lesions in Swedish women. However, the obvious predominance of HPV16 variant in squamous carcinomas was not seen in adenocarcinomas. A single amino-acid shift in the HPV16 E6 gene appears to result in a different transforming potential in squamous and glandular cervical lesions. (+info)