Histological features of human papilloma virus 16 and its association with the development and progression of anal squamous cell carcinoma

Clinicopathological aspects and prevalence of human papillomavirus in anal cancer

Anal cancer is relatively rare; however, its incidence has increased in recent years. Several risk factors are associated with the development of anal cancer, including age older than 50 years, low-fiber diet, chronic anal fistulas, smoking, multiple partners, anal intercourse practice, Human Immunodeficiency Virus infection and immunosuppression. However, the presence of human papillomavirus represents the main risk factor for the development of anal cancer. The aim of this study was to evaluate the clinicopathological aspects of a series of patients with anal carcinomas diagnosed in Hospital Araújo Jorge, Goiânia-Goiás, as well as the prevalence of human papillomavirus genome in these tumors. Clinical, pathological and socio-demographic data were collected from the respective medical files and paraffin blocks containing anal carcinomas specimens were used for DNA extraction and detection of human papillomavirus, by means of polymerase chain reaction, using short PCR fragment primers. Forty-three cases were selected and had the data analyzed, while 38 cases were tested for human papillomavirus genome detection. Among the evaluated patients, 62.8% were women; 53.4% of tumors were squamous cell carcinoma and 46.5% of the patients were aged between 60 and 75 years. Risk factors, such as smoking (39.5%) and alcoholism (20.9%) were recorded in the studied group. Lymph node metastases were detected in 30.2% of cases and 7.0% had distant metastasis. The detection of human papillomavirus DNA was positive in 76% of cases assessed and this was significantly associated with squamous cell carcinomas. Aggressive behavior and advanced stage of anal cancer described in this study highlight the need for preventive measures that contemplate these tumors, including vaccination against human papillomavirus.

Câncer anal e doenças sexualmente transmissíveis: qual a correlação?

OBJETIVO: O Câncer Anal é um tumor raro, cuja incidência é influenciada pelo comportamento sexual. O objetivo do trabalho é verificar a correlação entre o Câncer Anal e as Doenças Sexualmente Transmissíveis, como HPV, HIV, Infecção Gonocócica, Infecção por Clamídia, Sífilis e outras. MÉTODOS: Foram pesquisadas no site do Datasus as internações por Câncer Anal, HPV, HIV, Infecção Gonocócica, Infecção por Clamídia, Sífilis e outras DSTs, no SUS no Brasil, entre 1998 e 2007. O teste de correlação de Pearson foi aplicado. RESULTADOS: Há uma correlação positiva muito alta entre as internações por Câncer Anal e HPV (r = 0,98, p<0,001). Há uma correlação negativa entre as internações por Câncer Anal e as internações por Infecção Gonocócica (r = -0,81, p=0,005) e Infecção por Clamídia (r = -0,74, p=0,014). Não houve correlação estatisticamente significante entre Câncer Anal e as internações por HIV (r = 0,40, p=0,245), outras DSTs (r = 0,55, p=0,1) e Sífilis (r = -0,61, p=0,059). CONCLUSÃO: Há uma correlação positiva muito alta entre as internações por Câncer Anal e HPV no Brasil. Há uma correlação negativa entre as internações por Câncer Anal, Infecção Gonocócica e Infecção por Clamídia.

Early impact and performance characteristics of an established anal dysplasia screening program: program evaluation considerations

BACKGROUND

Screening for invasive anal cancer and its precursors is being increasingly advocated as a response to increasing incidence among HIV-infected persons. We implemented a comprehensive screening program in 2001 and report our early experience to inform monitoring and evaluation of such programs. Our research aims were: (1) to estimate incidence of and mortality from invasive anal cancer (IAC) before (1995-2000) and after (2001-2005) screening program implementation and (2) to examine potential screening program quality indicators.

METHODS

The study cohort included all patients under care for HIV infection at UCSD Owen Clinic between 1995-2005. Person-time incidence rates (IR) and case survival of IAC were estimated for the pre-screening (1995-2000) and post-screening (2001-2005) periods. High resolution anoscopy (HRA) operator accuracy was estimated by kappa agreement between cyto-histologic comparisons. Program quality indicators included: (1) screening coverage; (2) percent technically unsatisfactory cytology smears; (3) time between 1st abnormal cytology and 1st HRA; and (4) time between last clinic visit and last cytology.

RESULTS

28 cases of IAC and 13,411 person-years were observed between 1995-2005. IRs (95% CI) pre-screening and post-screening were 199 and 216 per 100,000 person-years, respectively. There was no routine treatment of high grade squamous intraepithelial lesions (HSIL) during the study period. The percent of patients with IAC requiring chemoradiation decreased from 90.9% to 70.6% (p=0.36). There was a significant improvement in cyto-histologic agreement at HRA with increasing operator experience (r=0.92, p=0.025). Screening coverage was 73% of the target population. Among 14 providers, the percent unsatisfactory cytology smears averaged 27% but varied from 0 - 62%. The median time from 1st abnormal cytology to 1st HRA was 258 days. The median interval between the last cytology and the last clinic visit was 207 days.

CONCLUSION

(1) The overall IR of IAC did not decline in the screening era and was higher than previous estimates for HIV cohorts; (2) stage shift to IAC of more favorable prognosis is a reasonable screening goal; (3) HRA accuracy varied by provider experience; (4) because of delay in access to HRA, digital rectal exam should be combined with cytology screening to detect palpable disease.