The association between smoking and cervical human papillomavirus infection among women from indigenous communities in western Botswana.

INTRODUCTION: Cervical cancer, a malignancy caused by infection with oncogenic human papillomavirus, disproportionally affects women from low resource settings. Persistence of human papillomavirus infection may mediate an association between tobacco use and cervical cancer. In limited resource settings, women from indigenous communities are often marginalized and do not benefit from evidence-based interventions to prevent tobacco use or cervical cancer due to the limited reach of mainstream healthcare services to these communities. This study determined the association between smoking and high-risk human papillomavirus infection among women from indigenous communities in western Botswana. METHODS: A cross-sectional study of women in indigenous communities was conducted between June and October 2022. Demographic, clinical and self-reported smoking data were collected. Cervical cytology and HPV DNA testing for high-risk human papillomavirus genotypes were performed. Multilevel multivariable logistic regression models were fit to evaluate the association between smoking and high-risk human papillomavirus infection while adjusting for potential confounders. RESULTS: A total of 171 participants with a median (interquartile range) age of 40 (31-50) years from three settlements and two villages were recruited for the study. Of these, 17% were current smokers, 32.8% were living with HIV and high-risk human papillomavirus DNA was detected in 32.8% of the cervical specimens. Women who were current smokers, were nearly twice as likely to have cervical high-risk human papillomavirus infection compared to non-smokers (Adjusted Odds Ratio (95% CI); 1.74(1.09, 2.79)) after controlling for confounders. CONCLUSION: These data underscore the need for effective tobacco control to help mitigate cervical cancer risk in this setting. These findings can help inform decisions about targeted cervical cancer prevention and tobacco cessation interventions for women from indigenous communities.

Prevalence of high-risk human papilloma virus in women with high-grade squamous cell intraepithelial lesions in Botswana using Abbott RealTime HPV assay.

BACKGROUND: High-risk human papillomavirus (HR-HPV) has been demonstrated to be the necessary cause of cervical carcinoma. High-risk HPV detection has a prognostic significance for the women who are at increased risk of disease progression. HPV genotyping in cervical cancer precursor lesions is crucial for prevention and management of cervical cancer. This study was designed to investigate the distribution of HR-HPV genotypes among a group of patients with high-grade squamous intraepithelial lesions and higher, of the cervix, in Botswana. MATERIALS AND METHODS: 185-archived residual formalin-fixed paraffin-embedded cervical biopsies collected between the years, 2006 and 2008 were studied. These tissues were diagnosed with HSIL (n = 146) and squamous cell carcinoma (n = 39). DNA was extracted using the Abbott m2000 analyser (Abbott Laboratories, Illinois) using reagents provided by the manufacturer. HPV genotyping was done using the Abbott RealTime HR-HPV PCR, which qualitatively detects 14 HR-HPV (reported as HPV 16, 18 & Other HR-HPV). RESULTS: DNA was successfully extracted from 162/185 (87.6%) tissues as indicated by a positive ß-globin test. 132/162 (82%) tested positive for HR-HPV The HPV 16 prevalence was 50% (66/132), HPV 18 at 15.2% (20/132) and other Group 1 HR-HPV plus HPV 66 and 68 had a prevalence of 56.1% (74/132). Other HR-HPV types were common in HSIL than in carcinoma, while HPV 16 was more prevalent in carcinomas than other HR-HPV genotypes. CONCLUSION: In this study, HPV 16 and other HR-HPV genotypes were commonly associated with HSIL but HPV 18 was uncommon among Botswana women. Our data highlights the need for multivalent HPV vaccines with cross coverage for other high risk HPV other than HPV 16 and 18.

Prevalence of oncogenic human papillomavirus genotypes in patients diagnosed with anogenital malignancies in Botswana.

BACKGROUND: Human papillomavirus (HPV) associated malignancies are the leading cause of cancer death in Botswana. We sought to determine causative HPV types in patients with anogenital malignancies in Botswana to inform vaccine strategy. METHODS: We used formalin-fixed and paraffin-embedded (FFPE) tissue blocks from patients diagnosed with anal, penile and vulvar squamous cell carcinomas between the years, 2014 and 2016. Presence of HPV 16, 18, or other high-risk (HR) types was detected using Abbott m2000 real-time PCR platform. Tissues with other high-risk types were subsequently analysed using a multiplex qPCR assay that includes 15 validated fluorophore probes. RESULTS: A total of 126 tissue specimens, comprising of 21 anal (9 males, 12 females), 31 penile and 74 vulvar were studied. Ninety-three (73.8%) patients had their HIV status documented in the records while the rest did not. Eighty-three (83) out of 93 were HIV positive, a prevalence of 89.4% (95% CI: 81-94). HPV was detected in 68/126 (54%) tissues, of which 69% (95% CI: 54-79) had HPV 16 only, 28% (95% CI: 19-40) had other hr.-HPV types and 2.9% (95% CI, 3.5-10.1) were co-infected with HPV 16 and other hr.-types. Other high-risk types detected included HPV 26, 31, 33, 35, 39, 45, 51, 52, 66 and 68. HPV 18 was not detected. Multiple-type HPV infection was detected in 44 of 47 (93.6%) HIV positive participants co-infected with HPV. In HIV-negative individuals, only HPV 16 was detected. CONCLUSION: In our study, anogenital carcinomas were associated with HPV 16 and other hr.-HPV types besides HPV 16 and 18. HIV co-infected patients had multiple hr.-HPV types detected whereas in HIV-negative patients only HPV 16 was detected. Our study suggests that multivalent vaccines may be more suitable in this setting, especially for HIV-infected individuals.