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Biomedical subjects

Philip E Castle

Publications and source records attributed to Philip E Castle.

At least 55 records · Page 3Linked to original sources
PubMed2004

Seroreactivity to human papillomavirus (HPV) types 16, 18, or 31 and risk of subsequent HPV infection: results from a population-based study in Costa Rica.

Whether antibodies to human papillomavirus (HPV) capsids, elicited by natural infection, are protective is unknown. This question was addressed in a population-based cohort of 7046 women in Costa Rica by examining the association between baseline seroreactivity to HPV-16, HPV-18, or HPV-31 virus-like particles and the risk of subsequent HPV infection at a follow-up visit 5-7 years after enrollment. Seropositivity to HPV-16, HPV-18, or HPV-31 was not associated with a statistically significant decreased risk of infection with the homologous HPV type [relative risk (RR) and [95% confidence interval (CI)], 0.74 (0.45-1.2), 1.5 (0.83-2.7), and 0.94 (0.48-1.8), respectively]. Seropositivity to HPV-16 or HPV-31 was not associated with a decreased risk of infection with HPV-16 or its genetically related types [RR (95% CI), 0.82 (0.61-1.1) and 0.93 (0.68-1.2), respectively]. Seropositivity to HPV-18 was not associated with a decreased risk of infection with HPV-18 or its genetically related types (RR 1.3; 95% CI 1.0-1.8). Thus, we did not observe immunity, although a protective effect from natural infection cannot be excluded because of the limits of available assays and study designs.

Adult↗
PubMed2004

Interlaboratory reliability of Hybrid Capture 2.

We evaluated the interlaboratory reproducibility of the Hybrid Capture 2 (HC2; Digene, Gaithersburg, MD), a test for oncogenic human papillomavirus (HPV) DNA, using data from 4 clinical center (CC) laboratories and the quality control (QC) laboratory participating in the ASCUS (atypical squamous cells of undetermined significance) and LSIL (low-grade squamous intraepithelial lesion) Triage Study (ALTS). Residual liquid cytology specimens were tested routinely throughout the duration of ALTS at CC laboratories, and a stratified (by time in the study) random sample of specimens was retested by the HPV QC laboratory using equivalent protocols. Of the specimens selected (N = 1,175, 5.50% of all specimens obtained), 1,072 (91.23%) had sufficient specimen volume for retesting. The kappa value between all CC laboratories and the HPV QC laboratory was 0.84 (95% confidence interval, 0.78-0.89), with kappa values for individual CCs and the HPV QC laboratory ranging from 0.79 to 0.89. Agreement between test results was lowest among results for women with negative cytologic findings (0.73); among those with equivocal or abnormal cytologic findings, kappa values were 0.80 or more. These data show that HC2 is a reliable test for detecting clinically relevant oncogenic HPV DNA.

Cytodiagnosis↗
PubMed2003

Effects of electron-beam irradiation on buccal-cell DNA.

Buccal cells were collected from 29 participants, by use of mouthwash rinses, and were split into equal aliquots, with one aliquot irradiated by electron-beam (E-beam) irradiation equivalent to the sterilizing dosage used by the U.S. Postal Service and the other left untreated. Aliquots were extracted and tested for DNA yields (e.g., TaqMan assay for quantifying human genomic DNA), genomic integrity, and amplification-based analysis of genetic variants (e.g., single-nucleotide polymorphisms [SNPs] and single tandem repeats [STRs]). Irradiated aliquots had lower median DNA yields (3.7 microg/aliquot) than untreated aliquots (7.6 microg/aliquot) (P<.0005) and were more likely to have smaller maximum DNA fragment size, on the basis of genomic integrity gels, than untreated aliquots (P<.0005). Irradiated aliquots showed poorer PCR amplification of a 989-bp beta-globin target (97% for weak amplification and 3% for no amplification) than untreated aliquots (7% for weak amplification and 0% for no amplification) (P<.0005), but 536-bp and 268-bp beta-globin targets were amplified from all aliquots. There was no detectable irradiation effect on SNP assays, but there was a significant trend for decreased detection of longer STRs (P=.01) in irradiated versus untreated aliquots. We conclude that E-beam irradiation reduced the yield and quality of buccal-cell specimens, and, although irradiated buccal-cell specimens may retain sufficient DNA integrity for some amplified analyses of many common genomic targets, assays that target longer DNA fragments (>989 bp) or require whole-genome amplification may be compromised.

Bioterrorism↗
PubMed2003

Cellular immune responses to human papillomavirus (HPV)-16 L1 in healthy volunteers immunized with recombinant HPV-16 L1 virus-like particles.

The causal association between papillomavirus (HPV) infection and cervical cancer has been demonstrated; the development of a prophylactic vaccine to protect against HPV infection may therefore reduce the incidence of this cancer worldwide. Noninfectious HPV-like particles (VLPs), composed of the L1 major capsid protein, are current candidate vaccines for prevention of HPV infection and cervical neoplasia. Although neutralizing antibodies have a pivotal role in the prevention of initial infection, cellular immune responses to HPV antigens may have an important role in viral clearance. A phase II trial was conducted to further evaluate the immunogenicity of a recombinant HPV-16 L1 VLP vaccine administered intramuscularly, without adjuvant, at 0, 1, and 6 months. Cell-mediated immune responses (lymphoproliferation and cytokine production) to HPV-16 L1 VLPs were evaluated in peripheral blood mononuclear cells (PBMCs) from 43 individuals receiving the L1 VLP vaccine and from 10 individuals receiving placebo. Vaccination resulted, at months 2 and 7 (i.e., 1 month after the second immunization and 1 month after third immunization, respectively), in increases in T cell-proliferative response to HPV-16 L1 VLPs (P<.001). In addition, significant increases in cytokine (interferon-gamma, interleukin [IL]-5 and IL-10) responses to L1 VLPs were observed after vaccination (P<.001). The strongest cytokine responses at month 7 were observed in individuals with high antibody titers at month 2, suggesting that neutralizing antibodies generated by initial vaccination may augment T cell responses to subsequent booster vaccinations. No significant increases in lymphoproliferative or cytokine responses to L1 VLPs were observed in individuals receiving placebo. In summary, the HPV-16 L1 vaccine induces not only robust B cell responses but also L1-specific T cell responses detectable by proliferation of both CD4+ and CD8+ T cells and in vitro production of both Th1- and Th2-type cytokines. Future efficacy studies are needed to evaluate whether and/or how VLP vaccines confer protection against genital HPV infection and associated disease.

Adolescent↗
PubMed2003

Stability of archived liquid-based cervical cytologic specimens.

BACKGROUND: Exfoliated cervical cell specimens collected in PreservCyt, a methanol-based medium used in ThinPrep liquid-based cytology, have been archived in epidemiologic studies. However, long-term DNA stability and cytologic stability of these biospecimens have not been evaluated. METHODS: Cervical specimens were collected into PreservCyt from participants in a natural history study of human papillomavirus (HPV) infection and cervical carcinoma in Guanacaste, Costa Rica (1993-2000), and stored at ambient temperatures. Thirty specimens classified as low-grade squamous intraepithelial lesions by liquid-based cytology were randomly chosen from each collection year (except for 1994) and selectively assessed for molecular and cytologic stability. Specimens were tested in 2001 for 1) HPV DNA by the Hybrid Capture 2 test, 2) beta-globin DNA by polymerase chain reaction amplification of multiple length fragments (268, 610, and 1327 bp), and 3) nuclear preservation by visual inspection of newly made liquid-based cytology slides. All testing was done masked to year of collection. Associations of stability and storage time were evaluated using standard contingency tables and chi-square tests for trend. RESULTS: Human papillomavirus DNA, as detected by the Hybrid Capture 2 test, was unaffected by storage time. Stability of beta-globin DNA (P(Trend) < 0.0001) and nuclear preservation (P(Trend) < 0.0001) declined with increasing storage time. Approximately 15% of specimens could not be amplified for any beta-globin DNA fragment after 5 years of storage (collected in 1996). In addition, cytology slides made from 41% specimens were rated as marginal (32%) or unsatisfactory (9%) after 8 years of storage (collected in 1993). CONCLUSIONS: Cervical specimens archived in PreservCyt underwent partial DNA and cytologic degradation after several years of storage. Methodologic studies to optimize long-term storage of cervical cells for epidemiologic studies of cervical carcinoma are needed.

Adult↗
PubMed2003

Baseline cytology, human papillomavirus testing, and risk for cervical neoplasia: a 10-year cohort analysis.

BACKGROUND: Annual Pap smear screening has been favored over less frequent screening in the United States to minimize the risk of cervical cancer. We evaluated whether simultaneous screening with a Pap test and human papillomavirus (HPV) testing is useful for assessing the risk for cervical intraepithelial neoplasia (CIN) 3 or cervical cancer. METHODS: We enrolled 23 702 subjects in a study of HPV infection at Kaiser Permanente, Northwest Division, Portland, OR. Data were analyzed for 20 810 volunteers who were at least 16 years old (mean = 35.9 years) with satisfactory baseline Pap tests and suitable samples for HPV testing. Women were followed for up to 122 months (from April 1, 1989, to June 30, 1999) to determine the risk for histopathologically confirmed CIN3 or cancer. RESULTS: Among 171 women with CIN3 or cancer diagnosed over 122 months, 123 (71.9%, 95% confidence interval [CI] = 65.2% to 78.7%) had baseline Pap results of atypical squamous cells or worse and/or a positive HPV test, including 102 (86.4%, 95% CI = 80.3% to 92.6%) of the 118 cases diagnosed within the first 45 months of follow-up. During this 45-month period, the cumulative incidence of CIN3 or cancer was 4.54% (95% CI = 3.61% to 5.46%) among women with a Pap test result of atypical squamous cells or worse, positive HPV tests, or both compared with 0.16% (95% CI = 0.08% to 0.24%) among women with negative Pap and HPV tests. Age, screening behavior, a history of cervical cancer precursors, and a history of treatment for CIN minimally affected results. CONCLUSIONS: Negative baseline Pap and HPV tests were associated with a low risk for CIN3 or cancer in the subsequent 45 months, largely because a negative HPV test was associated with a decreased risk of cervical neoplasia. Negative combined test results should provide added reassurance for lengthening the screening interval among low-risk women, whereas positive results identify a relatively small subgroup that requires more frequent surveillance.

Adolescent↗
PubMed2003

Detection of genomic amplification of the human telomerase gene (TERC) in cytologic specimens as a genetic test for the diagnosis of cervical dysplasia.

Invasive cervical carcinomas frequently reveal additional copies of the long arm of chromosome 3. The detection of this genetic aberration in diagnostic samples could therefore complement the morphological interpretation. We have developed a triple-color DNA probe set for the visualization of chromosomal copy number changes directly in thin-layer cervical cytology slides by fluorescence in situ hybridization. The probe set consists of a BAC contig that contains sequences for the RNA component of the human telomerase gene (TERC) on chromosome band 3q26, and repeat sequences specific for the centromeres of chromosomes 3 and 7 as controls. In a blinded study, we analyzed 57 thin-layer slides that had been rigorously screened and classified as normal (n = 13), atypical squamous cells (ASC, n = 5), low-grade squamous intraepithelial lesions (LSIL, n = 14), and high-grade squamous intraepithelial lesions (HSIL) grade 2 (CIN2, n = 8), and grade 3 (CIN3, n = 17). The percentage of tetraploid cells (P(Trend) < 0.0005) and cells with multiple 3q signals increased with the severity of the cytologic interpretation (P(Trend) < 0.0005). While only few normal samples, ASC and LSIL lesions, revealed copy number increases of 3q, 63% of the HSIL (CIN2) lesions and 76% of the HSIL (CIN3) lesions showed extra copies of 3q. We conclude that the visualization of chromosome 3q copy numbers in routinely prepared cytological material using BAC clones specific for TERC serves as an independent screening test for HSIL and may help to determine the progressive potential of individual lesions.

Algorithms↗
PubMed2003

Fertility and taxon-specific sperm binding persist after replacement of mouse sperm receptors with human homologs.

The zona pellucida surrounding ovulated mouse eggs contains three glycoproteins, two of which (ZP2 and ZP3) are reported sperm receptors. After fertilization, the zona pellucida is modified ad minimus by cleavage of ZP2, and sperm no longer bind. Crosstaxa sperm binding is limited among mammals, and human sperm do not bind to mouse eggs. Using transgenesis to replace mouse ZP2 and/or ZP3 with human homologs, mouse lines with human-mouse chimeric zonae pellucidae have been established. Unexpectedly, mouse, but not human, sperm bind to huZP2 and huZP2/huZP3 rescue eggs, eggs fertilized in vitro with mouse sperm progress to two-cell embryos, and rescue mice are fertile. Also unanticipated, human ZP2 remains uncleaved after fertilization, and mouse sperm continue to bind early rescue embryos. These observations are consistent with a model in which the supramolecular structure of the zona pellucida necessary for sperm binding is modulated by the cleavage status of ZP2.

Animals↗
PubMed2003

Chapter 4: Genital tract infections, cervical inflammation, and antioxidant nutrients--assessing their roles as human papillomavirus cofactors.

Cervical infections by approximately 15 human papillomavirus (HPV) types are the necessary cause of cervical cancer and its immediate precursor lesions. However, oncogenic HPV infections are usually benign and usually resolve within 1-2 years. A few of these infections persist and progress to cervical precancer and cancer. A number of cervical factors, such as infection by sexually transmitted pathogens other than HPV, cervical inflammation, and antioxidant nutrients, may influence the natural history of HPV infection along the pathways of persistence and progression or resolution. We examine the possible roles of these HPV cofactors in cervical carcinogenesis and discuss new methodologies that may enable researchers to measure relevant markers of the cervical microenvironment in which these cofactors may be active.

Antioxidants↗
PubMed2003

Chlamydia trachomatis, herpes simplex virus 2, and human T-cell lymphotrophic virus type 1 are not associated with grade of cervical neoplasia in Jamaican colposcopy patients.

BACKGROUND: A few recent studies have suggested that other sexually transmitted infections may increase the likelihood of a human papillomavirus (HPV) infection progressing to high-grade cervical neoplasia and cancer. GOAL: The goal was to assess whether exposures to Chlamydia trachomatis, human T-cell lymphotrophic virus type 1 (HTLV-I), and/or human simplex virus type 2 (HSV-2) are greater in colposcopy patients with cervical intraepithelial neoplasia grade 3 or cancer (CIN3+) than in patients with low-grade cervical neoplasia (CIN1). STUDY DESIGN: Sequential patients (n=447) attending a colposcopy clinic in Kingston, Jamaica, a country with high cervical cancer rates and high HTLV-I prevalence, were tested for (1) HPV DNA by L1 consensus primer (MY09/11) polymerase chain reaction assays, (2) C trachomatis DNA by ligase chain reaction, (3) C trachomatis antibodies by both microimmunofluorescence and a peptide (VS4) enzyme linked immunosorbent assay (ELISA), (4) HTLV-I antibodies by ELISA confirmed by western blotting, and (5) HSV-2 antibodies by a recombinant HSV-2-specific ELISA. Odds ratios and 95% confidence intervals were estimated with use of multinomial logistic regression models. RESULTS: HPV DNA detection was associated with grade of cervical neoplasia but other evaluated sexually transmitted infections were not. CONCLUSIONS: HTLV-I, C trachomatis, and/or HSV-2 were not associated with severity of cervical neoplasia in Jamaican women.

Adult↗
PubMed2003

Right-sided ectocervical lesions may be associated with false-negative cytology among women with histologic cervical intraepithelial neoplasia 2 or 3.

BACKGROUND: The association between the location of an ectocervical lesion and the sensibility of cytologic screening has not been adequately evaluated. METHODS: We evaluated the proportion of false-negative cytologic interpretations using three independent cytologic interpretations (conventional, PapNet, and ThinPrep) according to lesion location in 111 women with histologic cervical intraepithelial neoplasia 2 or 3 of a population-based study of cervical neoplasia conducted in Guanacaste, Costa Rica. Semiquantitative measures of human papillomavirus viral load were also considered. RESULTS: Lesions on a women's right ectocervix were associated with more frequent false-negative results than lesions on left ectocervix for each of the cytologic methods or when the most severe interpretation was considered (p = .004). Right-sided lesions had nonsignificantly lower viral loads than left-sided lesions (p = .2). CONCLUSIONS: Cervical intraepithelial neoplasia 2 or 3 located on the right side of the cervix may be poorly sampled with broom samplers in some settings, resulting in false-negative cytologic results.

Journal Article↗
PubMed2003

Comparison between prototype hybrid capture 3 and hybrid capture 2 human papillomavirus DNA assays for detection of high-grade cervical intraepithelial neoplasia and cancer.

We compared the performance of a prototype version of the Hybrid Capture 3 (HC3) human papillomavirus (HPV) DNA assay to the current generation Hybrid Capture 2 (HC2) assay, both of which target 13 oncogenic HPV types, for the detection of cervical intraepithelial neoplasia grade 3 and cancer (CIN3+) with cervicovaginal lavage specimens collected at enrollment into a 10-year cohort study at Kaiser Permanente (Portland, Oreg.). HC3 results for a risk-stratified sample (n = 4,364) were compared to HC2 results for the entire cohort (n = 20,810) with receiver operating characteristics curves, and the optimal cut points for both tests (relative light units [RLU]/positive control [PC]) for the detection of CIN3+ were determined. Specimens were also tested for HPV16 and HPV18 with separate HC3 type-specific probes. The optimal cut point for detecting CIN3+ was 1.0 RLU/PC for HC2, as previously shown, and was 0.6 RLU/PC for HC3. At the optimal cut points, HC3 and HC2 had similar screening performance characteristics for CIN3+ diagnosed at the enrollment visit. In analyses that included cases CIN3+ at enrollment and those diagnosed during early follow-up, HC3 had nonsignificantly higher sensitivity and equal specificity for the detection of CIN3+ compared to HC2; this increase in sensitivity was primarily the result of increased detection of CIN3+ in women who were 30 years of age or older and were cytologically negative (P = 0.006). We also compared the performance of the hybrid capture tests to MY09/11 L1 consensus primer PCR results (n = 1,247). HC3 was less likely than HC2 to test positive for specimens that tested positive by PCR for any untargeted types (P < 0.001). HC3 was less likely than HC2 to test positive for untargeted PCR-detected single infections with HPV53 (P = 0.001) and HPV66 (P = 0.01). There was good agreement between test positivity by PCR and by single type-specific HC3 probes for HPV16 (kappa = 0.76; 95% confidence interval [CI] = 0.71 to 0.82) and for HPV18 (kappa = 0.73; 95% CI = 0.68 to 0.79). In conclusion, we suggest that HC3 (>/=0.6 RLU/PC) may be slightly more sensitive than and equally specific test as HC2 (>/=1.0 RLU/PC) for the detection of CIN3+ over the duration of typical screening intervals.

Cross Reactions↗
PubMed2003

Human papillomavirus: epidemiology and public health.

Approximately 15 types of human papillomavirus (HPV) infection cause virtually all cases of cervical cancer. Human papillomavirus 16 is the major type, accounting for approximately 50% of cases. The major steps of cervical carcinogenesis include HPV infection, viral persistence and progression to precancer (as opposed to viral clearance), and invasion. Human papillomavirus is the most common sexually transmitted infection. However, most HPV infections become undetectable by even sensitive HPV DNA testing within 1 to 2 years. The prevalence of infection peaks at young ages and declines thereafter, perhaps as the result of HPV type-specific acquired immunity. Most HPV infections are neither microscopically evident nor visible, making HPV DNA detection the diagnostic reference standard. Poorly defined immunologic factors are the major determinants of viral outcome. Smoking, multiparity, and long-term oral contraceptive use increase the risk of persistence and progression. Other sexually transmitted infections (eg, Chlamydia trachomatis), chronic inflammation, and nutritional factors might also play a role. Overt, long-term viral persistence in the absence of precancer is uncommon. New prevention strategies can be derived from the evolving knowledge of HPV carcinogenesis. Human papillomavirus vaccination is the ultimate prevention strategy, and large-scale trials are already underway. In the meantime, HPV DNA diagnostics are more sensitive although less specific than cytology, permitting a consideration of lengthened screening intervals. In terms of public health education, clinicians and patients will need to shift discussions of the mildly abnormal Papanicolaou test to consideration of HPV infection as a common sexually transmitted infection that rarely causes cervical cancer.

Carrier State↗
PubMed2003

Immune profiling of plasma and cervical secretions using recycling immunoaffinity chromatography.

Small volumes of cervical secretions have limited measurements of immunity at the cervix, which may be important to studies of human papillomavirus (HPV). We report the use of recycling immunoaffinity chromatography to efficiently study immune profiles in cervical secretions. Frozen pairs of plasma and cervical secretions (collected on ophthalmic sponges) were selected randomly from women with normal cervical cytology (n = 50) participating in a natural history study of HPV in Guanacaste, Costa Rica. Single 25- micro l aliquots of plasma and (diluted) cervical secretions were assayed for interleukin (IL) -1 beta, -2, -4, -6, -8, -10, -12, -13, -15, IFN-alpha, -beta, -gamma, tumor necrosis factor-alpha, -beta, RANTES (regulated on activation normal T-cell express and secreted), MCP-1 (monocyte chemoattractant protein), -2, -3, macrophage inflammatory protein-1 alpha, -1 beta (regulated on activation normal T-cell express and secreted), macrophage colony-stimulating factor, IgG, IgA, and cyclooxygenase 2. All of the specimens were tested as blind replicates, and refrozen plasma was retested 4 months later. To evaluate the reproducibility of the repeat measurements and to examine the correlation between plasma and cervical secretions, we calculated kappa values with 95% confidence intervals among categorized analyte values and Spearman correlation coefficients (rho) among detectable, continuous analyte values. Measurements of all of the analytes in either plasma or cervical secretions were highly reproducible, with all of the kappa > or = 0.78 (70% above 0.90), and all of the rho > or = 0.88 (96% above 0.90). Only IL-1 beta (kappa = 0.60 and rho = 0.82) and IL-6 (kappa = 0.50 and rho = 0.78) levels were strongly correlated between plasma and cervical secretions. IFN-gamma, tumor necrosis factor-beta, RANTES, MCP-1, MCP -2, macrophage inflammatory protein-1 alpha, and macrophage colony-stimulating factor levels were especially poorly correlated between plasma and cervical secretions (kappa < or = 0.25 and rho < or = 0.25). We conclude that recycling immunoaffinity chromatography is a reproducible method of measuring immune profiles from biological specimens, and immune profiles are not well correlated between plasma and cervical secretions, perhaps necessitating cervical collections to study cervix-specific immunity in HPV natural history studies.

Adult↗
PubMed2002

Absolute risk of a subsequent abnormal pap among oncogenic human papillomavirus DNA-positive, cytologically negative women.

BACKGROUND: The addition of human papillomavirus (HPV) DNA testing to cytologic screening for cervical carcinoma is now being considered. The majority of women in screening cohorts who test positive for oncogenic types of HPV DNA have concurrent negative Pap tests. The absolute risk of a subsequent abnormal Pap test for these women is uncertain. Therefore, the proper counseling and clinical management of these women is also uncertain. METHODS: A subcohort of 2020 women with a negative Pap test who tested positive at enrollment for oncogenic HPV DNA types using the Hybrid Capture 2 Test were followed for 57 months at Kaiser Permanente (Portland, OR). Absolute risks of new abnormal cytologic interpretations were computed using Kaplan-Meier methods. Logistic regression models were used to evaluate determinants of a new abnormal Pap test. RESULTS: The cumulative incidence for a Pap test interpreted as atypical squamous cells or more severe (>or= ASC) was 16.8% (95% confidence interval [CI] = 15.0-18.6%), 6.4% (95% CI = 5.2-7.6%) for low-grade squamous intraepithelial lesions or more severe, and 2.2% (95% CI = 1.5-2.9%) for high-grade squamous intraepithelial lesions or more severe. By comparison, the cumulative incidence of greater than or equal to ASC among HPV-negative women was 4.2% (95% CI = 3.9-4.6%). The highest viral load (100 relative light units per the positive control or greater) was associated with a greater risk of an abnormal Pap test (odds ratio= 2.7, 95% CI = 1.7-4.1) than lower viral loads. CONCLUSIONS: These results suggest that about 15% of women in annual screening programs who concurrently have a negative Pap test and a positive oncogenic HPV test will have a subsequent abnormal Pap test within 5 years. This risk estimate will be useful to the many clinicians and patients likely to be diagnosed with an HPV infection and negative cytology if HPV DNA is added to general screening.

Adolescent↗
PubMed2002

A prospective study of high-grade cervical neoplasia risk among human papillomavirus-infected women.

BACKGROUND: In case-control studies, smoking, parity, and oral contraceptive use have been associated with an increased risk of cervical intraepithelial neoplasia grade 3 (CIN3) and cervical cancer among women who are infected with oncogenic human papillomavirus (HPV). However, these potential risk factors have not been adequately studied in prospective studies. METHODS: We studied 1812 women who were enrolled in a 10-year prospective study of cervical neoplasia at Kaiser Permanente in Portland, Oregon, and who at enrollment had tested positive for oncogenic HPV DNA and had responded to a questionnaire that included questions on smoking, oral contraceptive use, and parity. Absolute risks and crude relative risks (RRs) with 95% confidence intervals (CIs) for CIN3 or cervical cancer were computed for three time intervals (0-8, 9-68, and 69-122 months after enrollment) using the Kaplan-Meier method. Conditional logistic regression models were used to control for factors that may have influenced our risk estimates, specifically the cytologic interpretation of baseline Pap smear, number of Pap smears during follow-up, age at enrollment, age at prediagnosis visit, and age at diagnosis. All statistical tests were two-sided. RESULTS: Oral contraceptive use and parity were not associated with risk of CIN3 or cervical cancer. Former smokers, women who smoked less than one pack of cigarettes per day, and women who smoked one or more packs per day had crude RRs for CIN3 or cervical cancer for the entire follow-up period of 2.1 (95% CI = 1.1 to 3.9), 2.2 (95% CI = 1.2 to 4.2), and 2.9 (95% CI = 1.5 to 5.6), respectively, compared with never smokers. In the multivariable model, former smokers, women who smoked less than one pack/day, and women who smoked one or more packs/day had RRs of 3.3 (95% CI = 1.6 to 6.7), 2.9 (95% CI = 1.4 to 6.1), and 4.3 (95% CI = 2.0 to 9.3), respectively, for CIN3 or cervical cancer compared with never smokers. CONCLUSIONS: Smoking is associated with an increased risk of invasive cervical cancer in women who are infected with oncogenic HPV. Subsequent studies should examine the role of smoking in the multistage pathogenesis of cervical cancer.

Adult↗
PubMed2002

Human papillomavirus DNA remains detectable longer than related cervical cytologic abnormalities.

Cervical human papillomavirus (HPV) infections are at high risk of neoplastic progression if they persist. Persistence can be measured by repeated HPV DNA tests or by cytologic testing. Thus, it is useful to understand the relationship between these 2 measurements. To explore the relative timing of HPV DNA clearance versus cytologic regression, data were analyzed from 840 study participants who were followed-up by repeat thin-layer cytology and HPV testing by a hybrid capture test at 6-month intervals for 2 years. On average, HPV DNA detection persisted longer than related cytologic abnormalities (P<.001). HPV type-specific data from a subset of 448 women with complete polymerase chain reaction test data confirmed that HPV DNA persisted longer than cytologic abnormalities (P<.001). It appears that the natural history of HPV typically includes periods before and after cytologic abnormality, in which HPV DNA is the more sensitive indicator of infection.

Cervix Uteri↗