Human papillomavirus DNA prevalence and type distribution in anal carcinomas worldwide.

Knowledge about human papillomaviruses (HPV) types involved in anal cancers in some world regions is scanty. Here, we describe the HPV DNA prevalence and type distribution in a series of invasive anal cancers and anal intraepithelial neoplasias (AIN) grades 2/3 from 24 countries. We analyzed 43 AIN 2/3 cases and 496 anal cancers diagnosed from 1986 to 2011. After histopathological evaluation of formalin-fixed paraffin-embedded samples, HPV DNA detection and genotyping was performed using SPF-10/DEIA/LiPA25 system (version 1). A subset of 116 cancers was further tested for p16(INK4a) expression, a cellular surrogate marker for HPV-associated transformation. Prevalence ratios were estimated using multivariate Poisson regression with robust variance in the anal cancer data set. HPV DNA was detected in 88.3% of anal cancers (95% confidence interval [CI]: 85.1-91.0%) and in 95.3% of AIN 2/3 (95% CI: 84.2-99.4%). Among cancers, the highest prevalence was observed in warty-basaloid subtype of squamous cell carcinomas, in younger patients and in North American geographical region. There were no statistically significant differences in prevalence by gender. HPV16 was the most frequent HPV type detected in both cancers (80.7%) and AIN 2/3 lesions (75.4%). HPV18 was the second most common type in invasive cancers (3.6%). p16(INK4a) overexpression was found in 95% of HPV DNA-positive anal cancers. In view of the results of HPV DNA and high proportion of p16(INK4a) overexpression, infection by HPV is most likely to be a necessary cause for anal cancers in both men and women. The large contribution of HPV16 reinforces the potential impact of HPV vaccines in the prevention of these lesions.

Colonoscopic perforation: useful parameters for early diagnosis and conservative treatment.

OBJECTIVE: The purpose of this study is to determine useful parameters for the early diagnosis of colonoscopic perforation and to select those who would require surgical treatment. METHODS: We retrospectively reviewed the demographics, clinical and colonoscopic data, diagnostic-surgical interval, operative findings, complications, and hospital stay of patients who developed postcolonoscopy iatrogenic colonic perforation between January 2002 and December 2008. RESULTS: A retrospective multicentric study of patients diagnosed of colonoscopic perforation was performed. Fifty-four patients were found for final analysis (mean age, 71 years (26-91 years). Thirty-four were diagnostic and 20 were therapeutic colonoscopies. Most patients in whom the perforation was noticed during colonoscopy were treated surgically (p = 0.032) within 24 h (p = 0.004) and had a lesser degree of surgical peritonitis (p = 0.033). Those with deficient bowel preparation had more interventions (p < 0.05), ostomies (p = 0.015), and complications (p = 0.023) as well as major clinical (p < 0.001) and surgical peritonitis (p = 0.031). Patients with nonoperative management had fewer complications (p = 0.011) and lower hospital stay (p < 0.048). Surgical treatment within 24 h resulted in a lesser degree of surgical peritonitis (p < 0.001), fewer intestinal resections (p < 0.001), ostomies (p = 0.002) and complications (p < 0.047), and shorter hospital stay (p < 0.05). CONCLUSIONS: We recommend a conservative treatment for patients with the following conditions: good general health, unnoticed perforation during endoscopy, early diagnosis, no signs of diffuse peritonitis, proper colonic preparation, and a different injury mechanism to traction. Patients treated surgically after the first 24 h are likely to have a greater degree of peritonitis and more intestinal resections, ostomies, and complications.