Male circumcision and penile cancer: a systematic review and meta-analysis

OBJECTIVE: We systematically reviewed the evidence of an association between male circumcision and penile cancer. METHODS: Databases were searched using keywords and text terms for the epidemiology of penile cancer. Random effects meta-analyses were used to calculate summary odds ratios (ORs) and 95% confidence intervals (CI). RESULTS: We identified eight papers which evaluated the association of circumcision with penile cancer, of which seven were case-control studies. There was a strong protective effect of childhood/adolescent circumcision on invasive penile cancer (OR = 0.33; 95% CI 0.13-0.83; 3 studies). In two studies, the protective effect of childhood/adolescent circumcision on invasive cancer no longer persisted when analyses were restricted to boys with no history of phimosis. In contrast, there was some evidence that circumcision in adulthood was associated with an increased risk of invasive penile cancer (summary OR = 2.71; 95% CI 0.93-7.94; 3 studies). There was little evidence for an association of penile intra-epithelial neoplasia and in situ penile cancer with circumcision performed at any age. CONCLUSIONS: Men circumcised in childhood/adolescence are at substantially reduced risk of invasive penile cancer, and this effect could be mediated partly through an effect on phimosis. Expansion of circumcision services in sub-Saharan Africa as an HIV prevention strategy may additionally reduce penile cancer risk

Factors affecting the prevalence of strongly and weakly carcinogenic and lower-risk human papillomaviruses in anal specimens in a cohort of men who have sex with men (MSM)

Background: MSM are at higher risk for invasive anal cancer. Twelve human papillomaviruses (HPVs) cause cervical cancer in women (Group 1 high-risk HPVs (hrHPVs)) and 13 HPVs are probable/possible causes (Group 2 hrHPVs) of cervical malignancy. HPVs rarely associated with malignancy are classified as lower-risk HPVs (lrHPVs). Materials and Methods: Dacron-swab anal-cytology specimens were collected from and data complete for 97% (1262/1296) of Multicenter AIDS Cohort Study (MACS) men tested for HPVs using the Linear Array assay. Multivariate Poisson regression analyses estimated adjusted prevalence ratios for Group 1/2 hrHPVs and lrHPVs, controlling for the effects of age, race, ethnicity, sexual partnerships, smoking; HIV-infection characteristics, treatment, and immune status among HIV-infected men. Results: HIV-infected men showed 35-90% higher prevalence of Group 1/2 hrHPVs and lrHPVs than HIV-uninfected men, and higher prevalence of multi-Type, and multiple risk-group infections. CD4+ T-cell count was inversely associated with HPV Group 2 prevalence (p<0.0001). The number of receptive anal intercourse (RAI) partners reported in the 24 months preceding HPV testing predicted higher prevalence of Group 1/2 hrHPVs. Men reporting ≥30 lifetime male sex partners before their first MACS visit and men reporting ≥1 RAI partners during the 24 months before HPV testing showed 17-24% and 13-17% higher prevalence of lrHPVs (p-values ≤0.05). Men reporting smoking between MACS visit 1 and 24 months before HPV testing showed 1.2-fold higher prevalence of Group 2 hrHPVs (p = 0.03). Both complete adherence to CART (p = 0.02) and HIV load <50 copies/mL (p = 0.04) were protective for Group 1 hrHPVs among HIV-infected men. Conclusions: HIV-infected men more often show multi-type and multi-group HPV infections HIV-uninfected men. Long-term mutual monogamy and smoking cessation, generally, and CART-adherence that promotes (HIV) viremia control and prevents immunosuppression, specifically among HIV-infected MSM, are important prevention strategies for HPV infections that are relevant to anal cancer. © 2013 Wiley et al

Manejo dos portadores das neoplasias intraepiteliais anais Managment of anal intra-epithelial neoplasia patients

Acredita-se que a neoplasia intraepitelial anal (NIA), provocada pelo HPV, seja a lesão precursora do carcinoma anal. Segundo a literatura, são encontradas entre 11% e 52% dos homens infectados pelo HIV, entre 6% a 20% dos homens e 1% a 2,8% das mulheres sem essa infecção. Entre 8,5% e 13% das NIA de alto grau evoluirão para carcinoma invasivo, indicando a necessidade do rastreamento e do seguimento desses doentes para prevenção. Não há tratamento satisfatório com baixos índices de morbidez e a recidiva é comum. Em geral, as formas de tratamento podem de ser divididas em tópicas, entre elas, ácido tricloroacético, podofilina, podofilotoxina, imiquimod, terapia fotodinâmica, e ablativas, ou seja, excisão cirúrgica, ablação pelo LASER, coagulação pelo infravermelho e eletrofulguração. Há, ainda, os que consideram aceitável a conduta expectante. O tratamento tópico se justifica pelo caráter multifocal da lesão e os ablativos têm taxas de complicação e recidiva muito semelhantes. De qualquer forma, doentes com qualquer anormalidade histológica necessitam de seguimento adequado, principalmente com colposcopia e citologia anal.<br>Anal intra-epithelial neoplasia (AIN), provoked by HPV, is considered as an anal cancer precursor. Some articles noticed that it occurred among 11% and 52% of men who have sex with men (MSM) infected with HIV and, among seronegatives, from 6% to 20% of men and from 1% to 2.8% of women. From 8.5% to 13% of high grade AIN will evolve to invasive carcinoma, needing follow-up and screening for prevention. There is no satisfactory treatment with low morbidity and recurrence is frequent. There are two main forms of treatment: topics (trichloroacetic acid, podophylin, podophylotoxin, imiquimod, photodynamic therapy) and ablatives (chirurgical excision, LASER, infrared, eletrocautery). Others consider acceptable an expectant management. Topical therapy is justified because of multifocal presentation of HPV induced lesions and ablative treatments have similar incidences of morbidity and recurrence. Anyway, patients with histological abnormalities need suitable follow-up, with anal Pap smears and high resolution anoscopy

Tracking online topics over time: understanding dynamic hashtag communities

Abstract Background Hashtags are widely used for communication in online media. As a condensed version of information, they characterize topics and discussions. For their analysis, we apply methods from network science and propose novel tools for tracing their dynamics in time-dependent data. The observations are characterized by bursty behaviors in the increases and decreases of hashtag usage. These features can be reproduced with a novel model of dynamic rankings. Hashtag communities in time We build temporal and weighted co-occurrence networks from hashtags. On static snapshots, we infer the community structure using customized methods. On temporal networks, we solve the bipartite matching problem of detected communities at subsequent timesteps by taking into account higher-order memory. This results in a matching protocol that is robust toward temporal fluctuations and instabilities of the static community detection. The proposed methodology is broadly applicable and its outcomes reveal the temporal behavior of online topics. Modeling topic-dynamics We consider the size of the communities in time as a proxy for online popularity dynamics. We find that the distributions of gains and losses, as well as the interevent times are fat-tailed indicating occasional, but large and sudden changes in the usage of hashtags. Inspired by typical website designs, we propose a stochastic model that incorporates a ranking with respect to a time-dependent prestige score. This causes occasional cascades of rank shift events and reproduces the observations with good agreement. This offers an explanation for the observed dynamics, based on characteristic elements of online media