Co-factors related to the causal relationship between human papillomavirus and invasive cervical cancer in Honduras.

BACKGROUND: A case-control study was conducted in Honduras to identify co-factors in the carcinogenic pathway by which human papillomavirus (HPV) causes invasive cervical cancer. METHODS: Ninety-nine cases aged 23-65 (median 47) years participated. Two controls were matched to each case by age and clinic where they first presented for cytological screening; controls had no cervical abnormalities. Information on risk factors was obtained by personal interviews in the clinics regarding sociodemographic, reproductive and behavioral characteristics. Human papillomavirus was detected in cervical scrapes by general primer-mediated polymerase chain reaction (PCR) followed by sequence analysis to identify the different types present. RESULTS: All cases had squamous cell tumours and most were FIGO (International Federation of Gynecologists and Obstetricians) class II or higher; HPV was strongly associated with cervical cancer (odds ratio [OR] = 7.66, 95% CI : 3.88-15.1). Among HPV-positive women, dose-response relationships were observed for education, age at first intercourse and exposure to wood smoke that persisted after adjustment for previous screening. Among HPV-negative women, the number of sexual partners and parity were associated with cervical cancer. The protective effect of previous cytological screening operated independently of HPV. CONCLUSIONS: Our findings speak for the powerful role that both primary and secondary education plays in fostering a lifestyle that reduces the risk of invasive cervical cancer. The data suggest that important elements of such a lifestyle include later age at first sexual intercourse, a limited number of pregnancies, greater likelihood of undergoing cytological screening and reduced exposure to carcinogens in the household environment.

Human papillomavirus infection, cervical dysplasia and invasive cervical cancer in Honduras: a case-control study.

A substantial body of evidence has confirmed human papillomavirus (HPV) infection as the central etiological agent in human cervical carcinogenesis. In Honduras, cervical cancer is the most common cancer among women, with a high annual incidence. We conducted a population-based, case-control study of 229 patients with different grades of CIN and invasive cervical cancer and 438 matched controls. A structured questionnaire was used to investigate known and probable risk factors for cervical cancer. Cervical scrapes were tested for the presence of different HPV types using a general primer-mediated PCR followed by PCR-based sequencing. HPV DNA was detected in 87% of all cancer in situ and invasive cancer cases, and 95% of invasive cases could be attributed to high-risk types. In control women, 39% were positive for HPV DNA sequences. HPV 16 prevalence ranked highest in all stages of cervical dysplasias, invasive cancers and controls. A statistically significant association with HPV was observed for CIN II, CIN III and invasive cancer, showing an upward trend to more severe lesions and being more pronounced for HPV 16 and related types. The OR for HPV 16- and 18-related invasive cancer cases was 14.88 (95% CI 5.12-43.25) and 74.66 (95% CI 7.77-717.62), respectively. Our results confirm a central role of HPV as the cause of cervical cancer in Honduras and provide information as to the type distribution of HPVs in the country.

Human papillomavirus and cervical cancer in Honduran women.

In this study, the relationship between human papillomavirus (HPV) infections and cervical cancer in women from Honduras was investigated. Fifteen biopsy samples, obtained from women with cervical cancer or carcinoma in situ, were embedded in paraffin and investigated for the presence of HPV. One 5-microns section was directly processed in lysis buffer and treated with proteinase K. The samples were first screened with an HPV general primer polymerase chain reaction PCR (GP-PCR) assay directed against the highly conserved L1 open reading frame of HPV. The HPV-positive biopsy specimens were rescreened with an HPV 6/11, 16, 18, 31, and 33 type-specific PCR assay. All four carcinoma in situ samples and 10 of 11 carcinomas were found to be positive for HPV. Of the carcinoma in situ samples, two contained HPV 16 DNA, one sample contained HPV 18 DNA, and one sample both HPV 16 and HPV 18 DNA. Of the carcinomas, three specimens contained HPV 16 DNA, two samples contained HPV 18 DNA, two carcinomas were positive for both HPV 16 and 18 DNA, one sample contained HPV 6/11 DNA, and two specimens were HPV positive in the GP-PCR assay but HPV negative in the type-specific PCR assays. This indicated the presence of an HPV type different from HPV 6, 11, 16, 18, 31, or 33. In one carcinoma, no HPV DNA was detected. These data suggest a close association between infection with HPV 16 and HPV 18 and cervical cancer in Honduras.