Helen Trottier

Human Papillomavirus Infections with Multiple Types and Risk of Cervical Neoplasia

Background: Besides an established role for certain human papillomavirus (HPV) genotypes in the etiology of cervical cancer, little is known about the influence of multiple-type HPV infections on cervical lesion risk. We studied the association between multiple HPV types and cervical lesions among 2,462 Brazilian women participating in the Ludwig-McGill study group investigation of the natural history of HPVs and cervical neoplasia. Methods: Cervical specimens were typed by a PCR protocol. The cohorts repeated-measurement design permitted the assessment of the relation between the cumulative and concurrent number of HPV types and any-grade squamous intraepithelial lesions (SIL) and high-grade SIL (HSIL). Result: At individual visits, 1.9% to 3.2% of the women were infected with multiple HPVs. Cumulatively during the first year and the first 4 years of follow-up, 12.3% and 22.3% were infected with multiple types, respectively. HSIL risk markedly increased with the number of types [odds ratio (OR), 41.5; 95% confidence interval (95% CI), 5.3-323.2 for single-type infections; OR, 91.7; 95% CI, 11.6-728.1 for two to three types; and OR, 424.0; 95% CI, 31.8-5651.8 for four to six types, relative to women consistently HPV-negative during the first year of follow-up]. The excess risks for multiple-type infections remained after exclusion of women infected with HPV-16, with high-risk HPV types, or persistent infections, particularly for any-grade SIL. Coinfections involving HPV-16 and HPV-58 seemed particularly prone to increase risk. Conclusion: Infections with multiple HPV types seem to act synergistically in cervical carcinogenesis. These findings have implications for the management of cervical lesions and prediction of the outcome of HPV infections. (Cancer Epidemiol Biomarkers Prev 2006;15(7):1274–80)

HPV DNA, E6/E7 mRNA, and p16INK4a detection in head and neck cancers: a systematic review and meta-analysis

BACKGROUND We aimed to provide updated information about the global estimates of attributable fraction and type distribution of human papillomavirus (HPV) in head and neck squamous cell carcinomas by doing a systematic review and meta-analysis. METHODS We did a literature search on PubMed to identify studies that used PCR for detection of HPV DNA in head and neck squamous cell carcinomas with information about HPV genotype distribution. We included studies that tested 20 or more biopsies per cancer site and were published between July 15, 1990, and Feb 29, 2012. We collected information about sex, risk factors, HPV detection methods, and biomarkers of potentially HPV-induced carcinogenesis (E6/E7 mRNA and p16(INK4a)). If it was not possible to abstract the required information directly from the paper, we contacted the authors. We did a meta-analysis to produce pooled prevalence estimates including a meta-regression to explore sources of heterogeneity. FINDINGS 148 studies were included, contributing data for 12 163 cases of head and neck squamous cell carcinoma from 44 countries. HPV DNA was detected in 3837 cases. HPV16 accounted for 82·2% (95% CI 77·7-86·4) of all HPV DNA positive cases. By cancer site, pooled HPV DNA prevalence estimates were 45·8% (95% CI 38·9-52·9) for oropharynx, 22·1% (16·4-28·3) for larynx (including hypopharynx), and 24·2% (18·7-30·2) for oral cavity. The percent positivity of p16(INK4a) positive cases in HPV-positive oropharyngeal cancer cases was 86·7% (95% CI 79·2-92·9) and of E6/E7 mRNA positive cases was 86·9% (73·2-96·8). The estimate of HPV attributable fraction in oropharyngeal cancer defined by expression of positive cases of E6/E7 mRNA was 39·8% and of p16(INK4a) was 39·7%. Of subsites, tonsils (53·9%, 95% CI 46·4-61·3) had the highest HPV DNA prevalence. HPV DNA prevalence varied significantly by anatomical site, geographic region, but not by sex or tobacco or alcohol consumption. INTERPRETATION The contribution of HPV prevalence in head and neck squamous cell carcinoma and in particular that of HPV16 in the oropharynx shows the potential benefit of prophylactic vaccines. FUNDING European Commission.

High grade cervical lesions are caused preferentially by non-European variants of HPVs 16 and 18

The intratypic variability of HPVs 16 and 18 has been extensively studied and has been used as an important tool in epidemiological studies of viral transmission, persistence and progression to clinically relevant cervical lesions. Infections by non‐European variants of HPVs 16 and 18 are associated with an increased risk for the development of high grade squamous intraepithelial lesions (HSIL). Our aim was to correlate the intratypic molecular variability of both HPV types and risk of persistent infection and lesion outcome in a cohort study conducted in Brazil. We characterized molecular variants of HPV types 16 and 18 by sequencing a fragment of the LCR, and of the E6 and L1 genes, for HPV‐16 variants only. For both types, European variants composed the most prevalent and diverse group. Persistent infections with HPV‐18 were associated with continuous detection of European variants. However, risk for simultaneous detection of HSIL and HPV DNA was higher in women harboring non‐European variants of HPV‐16. The same trend was observed with HSIL detected during follow‐up. Our study confirms the association between non‐European variants and risk of cervical neoplasia, and highlights the importance of their geographic distribution for cervical cancer risk assessment.

Type-Specific Duration of Human Papillomavirus Infection: Implications for Human Papillomavirus Screening and Vaccination

BACKGROUND Understanding the duration of human papillomavirus (HPV) infection may help find suitable end points for vaccine trials and testing intervals in screening studies. We studied genotype-specific infection duration among 2462 women enrolled in the Ludwig-McGill cohort study. METHODS Cervical specimens collected every 4-6 months were tested by a polymerase chain reaction protocol. Actuarial techniques were used to estimate the duration of HPV infection and to investigate the influence of age, number of sexual partners, and coinfection with multiple HPV types. RESULTS At enrollment, the prevalence of infection with high-risk HPV types was 10.6%, and the prevalence of infection with low-risk HPV types was 6.1%; incidence rates were 6.1 and 5.0 infections per 1000 women-months, respectively. Prevalent infections took longer to clear than incident infections (mean time to clearance, 18.6 months vs. 13.5 months). The mean duration of incident infection with high- and low-risk HPV varied according to the analytic approach used to measure this variable and showed considerable variation by HPV type (range, 5.1-15.4 months). Age and number of partners did not influence infection duration, whereas coinfection was associated with increased infection duration. The mean duration of HPV-16 monoinfection was 11.0 months, and the mean duration of HPV-16 coinfection was 15.4 months. CONCLUSION There was considerable variation among HPV types with regard to the duration of infection. Coinfection with multiple types contributed to an increased infection duration.

HAART and Progression to High-Grade Anal Intraepithelial Neoplasia in Men Who Have Sex with Men and Are Infected with HIV

BACKGROUND Human immunodeficiency virus (HIV)-seropositive men who have sex with men (MSM) are at risk for anal intraepithelial neoplasia (AIN) and cancer. The goal of this study was to identify risk factors associated with high-grade AIN (AIN-2,3) in HIV-positive MSM, including the receipt of highly active antiretroviral therapy (HAART). METHODS A cohort study involving 247 HIV-seropositive MSM receiving HAART or initiating HAART was followed up every 6 months for 3 years with human papillomavirus (HPV) testing and high-resolution anoscopy to identify predictors of AIN-2,3 by Cox regression analysis and period prevalence logistic regression. RESULTS AIN-2,3 was observed during the study in 132 (53%) of 247 participants. The progression rate to AIN-2,3 from a lesser abnormality at baseline was 12.8 cases per 1000 person-months (95% confidence interval [CI], 9.8-16.5 cases per 1000 person-months). The risk of AIN-2,3 increased with age (odds ratio [OR], 3.09 [95% CI, 1.12-8.52] for men 40-49 years of age and 4.78 [95% CI, 1.29-17.73] for men >50 years of age, compared with men <40 years of age) and for men whose CD4+ cell counts were <50 cells/mm(3) before starting HAART (OR, 14.40 [95% CI, 1.45-143.58]). Men who had been receiving their current HAART regimen for >4 years had a marginally significant lower risk of AIN-2,3 after adjustment for HPV (OR, 0.28 [95% CI, 0.07-1.06]) compared with those treated for <4 years. Anal HPV type 16 (HPV16) or type 18 (HPV18) infections (OR, 14.18; [95% CI, 3.51-57.32]) and HPV16 and HPV18 co-infection (OR, 31.03 [ 95% CI, 5.68-169.60]) were strongly associated with progression to AIN-2,3. CONCLUSION HPV16 and HPV18 infections and a low nadir CD4+ cell count increase the risk of AIN-2,3. Receiving the same HAART regimen for >4 years may contribute some benefit against AIN-2,3.

Epidemiology of Mucosal Human Papillomavirus Infection and Associated Diseases

This article describes the epidemiology of mucosal human papillomavirs (HPV) in adults and children, its mode of transmission and its associated diseases. Over 40 genotypes of HPV infect the epithelial lining of the anogenital tract and other mucosal areas of the body. HPV is the most common sexually transmitted infection globally, with high prevalences found in both females and males. The predominant route of transmission is via sexual contact, although mother-to-child transmission is also possible. HPV infection may exist asymptomatically or may induce the formation of benign or malignant tumours in the genital, oral or conjunctival mucosa. Although most infections clear spontaneously, those that persist result in substantial morbidity and invoke high costs associated with the treatment of clinically relevant lesions. Some 13–18 mucosal HPV types are considered to have high oncogenic potential. HPV is recognized unequivocally as the main causal factor for cervical cancer, and is further responsible for a substantial proportion of many other anogenital neoplasms and head and neck cancers. Infections with HPV types that have low oncogenic risk, such as HPV-6 and 11, are associated with benign lesions of the anogenital areas known as condylomata acuminata (genital warts), oral papillomas, conjunctival papillomas, as well as low-grade squamous intra-epithelial lesions of the cervix. Perinatally acquired HPV can also cause recurrent respiratory papillomatosis in infants and young children. The implementation of HPV vaccination therefore has the potential to prevent a substantial proportion of HPV-related disease in the future.

Human Papillomavirus Infection and Reinfection in Adult Women: the Role of Sexual Activity and Natural Immunity

There is a paucity of data on whether or not women can be reinfected with human papillomavirus (HPV) types to which they were exposed to earlier in life and on the role of natural immunity. The observation of HPV infection at older ages may be explained by the reactivation of a latent infection or new exposure from sexual activity. Our objective was to analyze the association between reinfection and sexual activity. We analyzed data from 2,462 women enrolled in the Ludwig-McGill cohort and followed every 4 to 6 months for up to 10 years. We performed HPV typing and viral load measurements via PCR and determined HPV-16 seroreactivity at enrollment. Incidence of infection and reinfection were estimated for individual types. Adjusted relative risks (RR) for the association between infection/reinfection and new sexual partners were calculated using Cox regression. Rates of initial infection and reinfection postclearance were statistically comparable. RRs of initial infection or reinfection were consistently associated with new sexual partners [2.4 (95% confidence intervals; 95% CI, 2.0-3.1) for first infection, 3.7 (1.1-13.8) for reinfection with the same type, and 2.3 (1.5-3.7) for reinfection with a different type]. Reinfection in older women was also associated with new sexual partners (RR, 2.8; 95% CI, 1.4-5.3) as were new infections with HPV-16 among women with serologic evidence of prior HPV-16 exposure (RR, 3.0; 95% CI, 1.6-5.3). Viral loads at initial infection and at reinfection were comparable. HPV infection and reinfection were strongly associated with sexual activity. This study suggests that natural immunity does not play a role in controlling the extent of reinfections.

Role of repeated biopsy of the prostate in predicting disease progression in patients with prostate cancer on active surveillance

Active surveillance (AS) with deferred treatment is an established management option for patients with prostate cancer and favorable clinical parameters. The impact of repeat biopsy after diagnosis was examined in a cohort of men with prostate cancer on AS.

Red blood cell transfusion threshold in postsurgical pediatric intensive care patients: a randomized clinical trial.

Background:The optimal transfusion threshold after surgery in children is unknown. We analyzed the general surgery subgroup of the TRIPICU (Transfusion Requirements in Pediatric Intensive Care Units) study to determine the impact of a restrictive versus a liberal transfusion strategy on new or progressive multiple organ dysfunction syndrome (MODS). Methods:The TRIPICU study, a prospective randomized controlled trial conducted in 17 centers, enrolled a total of 648 critically ill children with a hemoglobin equal to or below 9.5 g/dL within 7 days of pediatric intensive care unit (PICU) admission to receive prestorage leukocyte-reduced red-cell transfusion if their hemoglobin dropped below either 7.0 g/dL (restrictive) or 9.5 g/dL (liberal). A subgroup of 124 postoperative patients (60 randomized to restrictive and 64 to the liberal group) were analyzed. This study was registered at http://www.controlled-trials.com and carries the following ID ISRCTN37246456. Results:Participants in the restrictive and liberal groups were similar at randomization in age (restrictive vs. liberal: 53.5 ± 51.8 vs. 73.7 ± 61.8 months), severity of illness (pediatric risk of mortality [PRISM] score: 3.5 ± 4.0 vs. 4.4 ± 4.0), MODS (35% vs. 29%), need for mechanical ventilation (77% vs. 74%), and hemoglobin level (7.7 ± 1.1 vs. 7.9 ± 1.0 g/dL). The mean hemoglobin level remained 2.3 g/dL lower in the restrictive group after randomization. No significant differences were found for new or progressive MODS (8% vs. 9%; P = 0.83) or for 28-day mortality (2% vs. 2%; P = 0.96) in the restrictive versus liberal group. However, there was a statistically significant difference between groups for PICU length of stay (7.7 ± 6.6 days for the restrictive group vs. 11.6 ± 10.2 days for the liberal group; P = 0.03). Conclusions:In this subgroup analysis of pediatric general surgery patients, we found no conclusive evidence that a restrictive red-cell transfusion strategy, as compared with a liberal one, increased the rate of new or progressive MODS or mortality.

Delays in diagnosis and treatment among children and adolescents with cancer in Canada.

Few studies have investigated delays in diagnosis and treatment among children and adolescents with cancer, especially from the perspective of an entire country. Detailed understanding of delays along the continuum of cancer patient care is important in order to establish appropriate benchmarks for timely oncological care. Our objective was to characterise the different components of delay in 2,896 Canadian children and adolescents (aged 0–19 years) with cancer that were enrolled in the Treatment and Outcome Surveillance component of the Canadian Childhood Cancer Surveillance and Control Program from 1995 to 2000.