Laia Bruni

Worldwide prevalence and genotype distribution of cervical human papillomavirus DNA in women with normal cytology: a meta-analysis.

We set out to estimate the age and genotype-specific prevalence of cervical human papillomavirus (HPV) DNA in women with normal cervical cytology worldwide by meta-analysis of a systematic literature review. Reports on HPV prevalence published between January, 1995, and January, 2005, were retrieved. To be included, studies required information on cervical cytology, plus detailed descriptions of study populations, methods used to collect cervical samples, and assays used for HPV DNA detection and typing. Final analyses included 78 studies that could be separated into women with normal cytology, and of which subsets of 44 and 48 studies had data on age and type-specific HPV prevalence, respectively. Overall HPV prevalence in 157 879 women with normal cervical cytology was estimated to be 10.4% (95% CI 10.2-10.7). Corresponding estimates by region were Africa 22.1% (20.9-23.4), Central America and Mexico 20.4% (19.3-21.4), northern America 11.3% (10.6-12.1), Europe 8.1% (7.8-8.4), and Asia 8.0% (7.5-8.4). In all world regions, HPV prevalence was highest in women younger than 35 years of age, decreasing in women of older age. In Africa, the Americas, and Europe, a clear second peak of HPV prevalence was observed in women aged 45 years or older. On the basis of these estimates, around 291 million women worldwide are carriers of HPV DNA, of whom 32% are infected with HPV16 or HPV18, or both. The HPV types most commonly detected are similar to those most commonly described in pre-neoplastic and cancer cases, although the relative contribution of HPV16 and HPV18 is substantially lower in cytologically normal women.

Cervical Human Papillomavirus Prevalence in 5 Continents: Meta-Analysis of 1 Million Women with Normal Cytological Findings

BACKGROUND Baseline information on human papillomavirus (HPV) prevalence and type distribution is highly desirable to evaluate the impact of prophylactic HPV vaccines in the near future. METHODS A meta-analysis was performed of studies published between 1995 and 2009 that used polymerase chain reaction or Hybrid Capture 2 for HPV detection in women with normal cytological findings. RESULTS The analysis included 194 studies comprising 1,016,719 women with normal cytological findings. The estimated global HPV prevalence was 11.7% (95% confidence interval, 11.6%-11.7%). Sub-Saharan Africa (24.0%), Eastern Europe (21.4%), and Latin America (16.1%) showed the highest prevalences. Age-specific HPV distribution presented with a first peak at younger ages (<25 years) and, in the Americas and Africa, a rebound at older ages (≥45 years). Among the women with type-specific HPV data (n = 215,568), the 5 most common types worldwide were HPV-16 (3.2%), HPV-18 (1.4%), HPV-52 (0.9%), HPV-31 (0.8%), and HPV-58 (0.7%). CONCLUSIONS Although the prevalence of HPV in women with normal cytological findings is high and variable across world regions, HPV types 16, 18, 31, 52, and 58 are consistently found among the 10 most common types in all of them. These results represent the most comprehensive assessment of HPV burden among women with normal cytological findings in the pre-HPV vaccination era worldwide.

Epidemiology and Natural History of Human Papillomavirus Infections and Type-Specific Implications in Cervical Neoplasia

Worldwide human papillomavirus (HPV) prevalence in women with normal cytology at any given point in time is approximately 10% indicating that HPV is one of the most common sexually transmitted infections. HPV-16 is consistently the most common type and HPV-18 the second with some minor regional differences. Furthermore, across the spectrum of cervical lesions, HPV-16 is consistently the most common HPV type contributing to 50-55% of invasive cervical cancer cases strongly suggesting that this viral type has a biological advantage for transmission, persistency and transformation. The same phenomenon is observed albeit at a lower level for HPV-18 and HPV-45. Sexual behavioral patterns across age groups and populations are central to the description of the HPV circulation and of the risk of infection. The concept of group sexual behavior (in addition to individual sexual behavior) is important in exploring HPV transmission and has implications for defining and monitoring HPV and cancer prevention strategies. In natural history studies, the pattern of HPV DNA prevalence by age groups is similar to the patterns of HPV incidence. Rates of exposure in young women are high and often include multiple types. There is a spontaneous and rapid decrease of the HPV DNA detection rates in the middle-age groups followed by a second rise in the post-menopausal years. This article reviews: 1) the evidence in relation to the burden of HPV infections in the world and the contributions of each HPV type to the spectrum of cervical cellular changes spanning from normal cytology to invasive cervical cancer; 2) the critical role of the patterns of sexual behavior in the populations; and 3) selected aspects of the technical and methodological complexity of natural history studies of HPV and cervical neoplasia.

Worldwide burden of cervical cancer in 2008

BACKGROUND The knowledge that persistent human papillomavirus infection is the main cause of cervical cancer has resulted in the development of assays that detect nucleic acids of the virus and prophylactic vaccines. Up-to-date and reliable data are needed to assess impact of existing preventive measures and to define priorities for the future. MATERIALS AND METHODS Best estimates on cervical cancer incidence and mortality are presented using recently compiled data from cancer and mortality registries for the year 2008. RESULTS There were an estimated 530,000 cases of cervical cancer and 275,000 deaths from the disease in 2008. It is the third most common female cancer ranking after breast (1.38 million cases) and colorectal cancer (0.57 million cases). The incidence of cervical cancer varies widely among countries with world age-standardised rates ranging from <1 to >50 per 100,000. Cervical cancer is the leading cause of cancer-related death among women in Eastern, Western and Middle Africa; Central America; South-Central Asia and Melanesia. The highest incidence rate is observed in Guinea, with ∼6.5% of women developing cervical cancer before the age of 75 years. India is the country with the highest disease frequency with 134,000 cases and 73 000 deaths. Cervical cancer, more than the other major cancers, affects women <45 years. CONCLUSIONS In spite of effective screening methods, cervical cancer continues to be a major public health problem. New methodologies of cervical cancer prevention should be made available and accessible for women of all countries through well-organised programmes.

Human papillomavirus types in 115,789 HPV‐positive women: A meta‐analysis from cervical infection to cancer

Genotyping may improve risk stratification of high‐risk (HR) human papillomavirus (HPV)‐positive women in cervical screening programs; however, prospective data comparing the natural history and carcinogenic potential of individual HR types remain limited. A meta‐analysis of cross‐sectional HR HPV‐type distribution in 115,789 HPV‐positive women was performed, including 33,154 normal cytology, 6,810 atypical squamous cells of undetermined significance (ASCUS), 13,480 low‐grade squamous intraepithelial lesions (LSIL) and 6,616 high‐grade SIL (HSIL) diagnosed cytologically, 8,106 cervical intraepithelial neoplasia grade 1 (CIN1), 4,068 CIN2 and 10,753 CIN3 diagnosed histologically and 36,374 invasive cervical cancers (ICCs) from 423 PCR‐based studies worldwide. No strong differences in HPV‐type distribution were apparent between normal cytology, ASCUS, LSIL or CIN1. However, HPV16 positivity increased steeply from normal/ASCUS/LSIL/CIN1 (20–28%), through CIN2/HSIL (40/47%) to CIN3/ICC (58/63%). HPV16, 18 and 45 accounted for a greater or equal proportion of HPV infections in ICC compared to normal cytology (ICC:normal ratios = 3.07, 1.87 and 1.10, respectively) and to CIN3 (ICC:CIN3 ratios = 1.08, 2.11 and 1.47, respectively). Other HR types accounted for important proportions of HPV‐positive CIN2 and CIN3, but their contribution dropped in ICC, with ICC:normal ratios ranging from 0.94 for HPV33 down to 0.16 for HPV51. ICC:normal ratios were particularly high for HPV45 in Africa (1.85) and South/Central America (1.79) and for HPV58 in Eastern Asia (1.36). ASCUS and LSIL appear proxies of HPV infection rather than cancer precursors, and even CIN3 is not entirely representative of the types causing ICC. HPV16 in particular, but also HPV18 and 45, warrant special attention in HPV‐based screening programs.

Human papillomavirus prevalence and type distribution in penile carcinoma

Background: Penile carcinoma is an uncommon and potentially mutilating disease with a heterogeneous aetiology. Several risk factors have been established for its development. Human papillomavirus (HPV) infection seems to play an important role in the development of a subset of these carcinomas and its presence is thought to be related to the histological type. HPV prevalence in penile tumours is reported to be associated to a variety of morphological changes. Its determination will provide a better estimate for HPV related cancer burden and its preventable fraction. Methods: A systematic and comprehensive literature review of the major penile cancer studies published from 1986 until June 2008 evaluating the HPV prevalence among the different histological types was carried out. Results: 31 studies including 1466 penile carcinomas were reviewed. Global HPV prevalence was 46.9%. Relative contribution was: HPV-16 (60.23%), HPV-18 (13.35%), HPV-6/11 (8.13%), HPV-31 (1.16%), HPV-45 (1.16%), HPV-33 (0.97%), HPV-52 (0.58%), other types (2.47%). Assessment of multiple infections contribution is limited due to study design. Basaloid and warty squamous cell carcinomas were the most frequent HPV-related histological types, but keratinising and non-keratinising subtypes also showed prevalence rates of around 50%. Conclusions: About half of the penile tumours were associated with HPV 16–18 with little presence of other genotypes. Research on the mechanisms behind penile carcinogenesis is warranted. Available HPV vaccines are likely to be effective in penile tumours.

Potential impact of a nine-valent vaccine in human papillomavirus related cervical disease

BackgroundInformation on human papillomavirus (HPV) type distribution is necessary to evaluate the potential impact of current and future HPV vaccines. We estimated the relative contribution (RC) to invasive cervical cancer (ICC) and precancerous cervical lesions of the nine HPV types (HPV 6/11/16/18/31/33/45/52/58) included in an HPV vaccine currently under development.MethodsEstimations on ICC were based on an international study of 8,977 HPV positive cases and estimations on precancerous cervical lesions were extracted from a published meta-analysis including 115,789 HPV positive women. Globocan 2008 and 2010 World Population Prospects were used to estimate current and future projections of new ICC cases.ResultsRC of the 9 HPV types in ICC was 89.4%, with 18.5% of cases positive for HPV 31/33/45/52/58. Regional variations were observed. RCs varied by histology, ranging between 89.1% in squamous cell carcinomas (SCC) and 95.5% in adenocarcinomas (ADC). HPV 16/18/45 were detected in 94.2% of ADC. RC of the 9 types altogether decreased with age (trend test p < 0.0001), driven by the decrease in older ages of HPV 16/18/45. In contrast, the RC of HPV 31/33/52/58 increased with age. Due to population growth alone, projected estimates of ICC cases attributable to the 9 types are expected to rise from 493,770 new cases in 2012 to 560,887 new cases in 2025.The RCs of individual high risk HPV types varied by cytological and histological grades of HPV-positive precancerous cervical lesions, and there was an under representation of HPV 18 and 45 compared to ICC.ConclusionsThe addition of HPV 31/33/45/52/58 to HPV types included in current vaccines could prevent almost 90% of ICC cases worldwide. If the nine-valent vaccine achieves the same degree of efficacy than previous vaccines, world incidence rates could be substantially reduced.

EUROGIN 2011 roadmap on prevention and treatment of HPV-related disease

The EUROGIN 2011 roadmap reviews the current burden of human papillomavirus (HPV)‐related morbidity, as well as the evidence and potential practice recommendations regarding primary and secondary prevention and treatment of cancers and other disease associated with HPV infection. HPV infection causes ∼600,000 cases of cancer of the cervix, vulva, vagina, anus and oropharynx annually, as well as benign diseases such as genital warts and recurrent respiratory papillomatosis. Whereas the incidence of cervical cancer has been decreasing over recent decades, the incidence of anal and oropharyngeal carcinoma, for which there are no effective screening programs, has been rising over the last couple of decades. Randomized trials have demonstrated improved efficacy of HPV‐based compared to cytology‐based cervical cancer screening. Defining the best algorithms to triage HPV‐positive women, age ranges and screening intervals are priorities for pooled analyses and further research, whereas feasibility questions can be addressed through screening programs. HPV vaccination will reduce the burden of cervical precancer and probably also of invasive cervical and other HPV‐related disease in women. Recent trials demonstrated that prophylactic vaccination also protects against anogenital HPV infection, anogenital intraepithelial lesions and warts associated with vaccine types, in males; and anal HPV infection and anal intraepithelial neoplasia in MSM. HPV‐related oropharyngeal cancer could be treated less aggressively because of better survival compared to cancers of the oropharynx unrelated to HPV. Key findings in the field of cervical cancer prevention should now be translated in cost‐effective strategies, following an organized approach integrating primary and secondary prevention, according to scientific evidence but adapted to the local situation with particular attention to regions with the highest burden of disease.

Burden and trends of type-specific human papillomavirus infections and related diseases in the latin america and Caribbean region.

We present the burden of human papillomavirus (HPV)-related cancers (cancers of the cervix, anogenital region, oral cavity and pharynx) in terms of incidence and mortality, for the countries of the Latin America and Caribbean region. The region is a high-risk area for cancer of the cervix and, although incidence has declined since the 1960s, projected demographic changes imply that the actual burden of new cases will increase by more than 75% in the next 20 years, while the average and at diagnosis will increase. Approximately 65% of cervical cancer cases and 50% of the high risk lesions are associated with HPV-16 and 18. Incidence rates of other HPV-related cancers are significantly lower. The paper also describes the estimated impact of genital warts and the limited data available on the occurrence of HPV infections of the upper aerodigestive tract in the region.

Clinical malaria in African pregnant women

BackgroundThere is a widespread notion, based on limited information, that in areas of stable malaria transmission most pregnant women with Plasmodium falciparum infection are asymptomatic. This study aim to characterize the clinical presentation of malaria in African pregnant women and to evaluate the adequacy of case management based on clinical complaints.MethodsA hospital-based descriptive study between August 2003 and November 2005 was conducted at the maternity clinic of a rural hospital in Mozambique. All women attending the maternity clinic were invited to participate. A total of 2,330 women made 3,437 eligible visits, 3129 were analysed, the remainder were excluded because diagnostic results were unavailable or they were repeat visits. Women gave a standardized clinical history and had a medical exam. Malaria parasitaemia and haematocrit in capillary blood was determined for all women with signs or symptoms compatible with malaria including: presence and history of fever, arthromyalgias, headache, history of convulsions and pallor. Outcome measure was association of malaria symptoms or signs with positive blood slide for malaria parasitaemia.ResultsIn 77.4% of visits pregnant women had symptoms suggestive of malaria; 23% (708/3129) were in the first trimester. Malaria parasitaemia was confirmed in 26.9% (842/3129) of visits. Headache, arthromyalgias and history of fever were the most common symptoms (86.5%, 74.8% and 65.4%) presented, but their positive predictive values for malaria parasitaemia were low [28% (27–30), 29% (28–31), and 33% (31–35), respectively].ConclusionSymptoms suggestive of malaria were very frequent among pregnant women attending a rural maternity clinic in an area of stable malaria transmission. However, less than a third of them were parasitaemic. In the absence of microscopy or rapid diagnostic tests, a large proportion of women, including those in the first trimester of gestation, would be unnecessarily receiving antimalarial drugs, often those with unknown safety profiles for pregnancy. Accessibility to malaria diagnostic tools needs to be improved for pregnant women and drugs with a safety profile in all gestational ages are urgently needed.