Crispin Kahesa

Association between invasive cancer of the cervix and HIV-1 infection in Tanzania: the need for dual screening

BackgroundCancer of the cervix is the second commonest malignancy in females worldwide and is the leading malignancy among women in Tanzania. Cancer of the cervix has been strongly associated with Human Papilloma Virus (HPV) which is a sexually transmitted disease. However, the role of HIV-1 in the aetiology of cancer of the cervix is less clear. Studies suggest that HPV and HIV-1 infection are synergistic and therefore their dual occurrence may fuel increased incidence of cancer of the cervix and AIDS. We therefore conducted a study to determine the association between cancer of the cervix and HIV-1.MethodsThe study was carried out in Ocean Road Cancer Institute, Dar-es-salaam, Tanzania between January and March 2007. A hospital-based case control design was used to study 138 cases and 138 controls. The cases were consenting women 18 years and above with histologically confirmed squamous cell carcinoma of the cervix, while the controls were consenting non-cancer adult women attendants or visitors. The participants were counselled and tested for HIV-1 and interviewed to assess risk factors for cancer of the cervix and HIV-1. Estimation of risk was done by computing odds ratios and confidence intervals. Confounding and interaction between the factors were assessed using logistic regression.ResultsHIV-1 prevalence was much higher among the cases (21.0%) than among the controls (11.6%). In logistic regression, HIV-1 was associated with cancer of the cervix (OR = 2.9, 95% CI = 1.4–5.9). Among the cases the mean age was lower for HIV-1 infected (44.3 years) than HIV-1 uninfected women (54 years, p = 0.0001).ConclusionHIV-1 infection is associated with invasive cancer of the cervix. Resource-constrained countries with a high burden of HIV-1 and cervical cancer should adopt a high-risk approach that targets HIV-1 positive women for screening of cervical cancer initially by utilizing HIV/AIDS resources.

Human papillomavirus prevalence and type distribution in 3603 HIV-positive and HIV-negative women in the general population of Tanzania: the PROTECT study.

Objective: The aim of the Prevention of Cervical Cancer in Tanzania (PROTECT) study is to assess the prevalence of oncogenic human papillomavirus (HPV) and to determine the type distribution among women in the general population according to human immunodeficiency virus (HIV) status, in preparation for a potential HPV immunization program. Methods: We included 3603 women from the general population in urban and rural areas of Tanzania. All women underwent a gynecological examination where a Pap smear was obtained and cervical cells were collected to assess the presence of high-risk (HR) HPV DNA by hybrid capture 2 test. Genotyping was performed by the LiPaExtra method. These women were also tested for HIV. Results: The prevalence of HR HPV types was 20.1%, ranging from 14.8% in women with normal cytology to 94.2% in women with high grade squamous intraepithelial lesion (HSIL) or worse (100% in 5 cancers). In women with normal cytology or low-grade lesions, the most common type was HPV52 (3.2%), followed by HPV16 (2.1%). In contrast, HPV16 was the dominating type in HSIL or worse (32.8%). No cancers contained HPV52. The HR HPV prevalence was higher in HIV-positive women (46.7%) than in HIV-negative women (17.2%). No specific HR HPV types were significantly more common in HIV-positive women. Conclusion: The HPV type distribution is similar in HIV-positive and HIV-negative women. These results suggest that the HPV vaccines that are currently available could protect women from HPV infection independently of their HIV status.

Determinants of acceptance of cervical cancer screening in Dar es Salaam, Tanzania

ObjectiveTo describe how demographic characteristics and knowledge of cervical cancer influence screening acceptance among women living in Dar es Salaam, Tanzania.MethodsMultistage cluster sampling was carried out in 45 randomly selected streets in Dar es Salaam. Women between the ages of 25–59 who lived in the sampled streets were invited to a cervical cancer screening; 804 women accepted and 313 rejected the invitation. Information on demographic characteristics and knowledge of cervical cancer were obtained through structured questionnaire interviews.ResultsWomen aged 35–44 and women aged 45–59 had increased ORs of 3.52 and 7.09, respectively, for accepting screening. Increased accepting rates were also found among single women (OR 2.43) and among women who had attended primary or secondary school (ORs of 1.81 and 1.94). Women who had 0–2 children were also more prone to accept screening in comparison with women who had five or more children (OR 3.21). Finally, knowledge of cervical cancer and awareness of the existing screening program were also associated with increased acceptance rates (ORs of 5.90 and 4.20).ConclusionThere are identifiable subgroups where cervical cancer screening can be increased in Dar es Salaam. Special attention should be paid to women of low education and women of high parity. In addition, knowledge and awareness raising campaigns that goes hand in hand with culturally acceptable screening services will likely lead to an increased uptake of cervical cancer screening.

Risk factors for high-risk human papillomavirus detection among HIV-negative and HIV-positive women from Tanzania.

Background Human papillomavirus (HPV) is one of the most common sexually transmitted infections worldwide. The prevalence is dependent on several known factors notably sexual behavior and age, and factors still under scrutiny. Objective This study aimed to examine risk factors for high-risk (HR) HPV infection among HIV-positive and HIV-negative women from the general population of Tanzania and to assess whether specific risk factors could contribute to the high prevalence of HR HPV infection in older age found in some populations including Tanzanian women. Methods A cross-sectional study of 3699 women from Tanzania was conducted. We obtained information on sociodemographic and lifestyle factors through personal interview. Cervical swabs were collected for detection of HR HPV (Hybrid Capture 2; Qiagen, Hildesheim, Germany) and genotyping (LiPaExtra; Innogenetics, Gent, Belgium). Finally, we obtained a blood sample for HIV testing. Results HIV positivity was the strongest risk factor for HR HPV (odds ratio, 4.1; 95% confidence interval, 3.3–5.3). Young age, shorter duration of present relationship, and increasing number of sex partners were also associated with higher risk for HR HPV. Among women 20 to 29 years old, especially number of partners (P = 0.005) and HIV positivity (P < 0.0001) determined the risk. In underweight women 50 years or older (P = 0.004) and HIV positivity (P = 0.0009) increased the risk, whereas increasing number of partners was not related to the risk of HR HPV (P = 0.46). Conclusions Human papillomavirus risk factors among HIV-positive and HIV-negative women were similar, but the strength of association was greater among HIV-positive women, notably for lifetime number of sex partners, time in present relationship, genital warts, and body mass index. We were not able to identify a clear explanation for the high HPV prevalence among older women. However, in the age-stratified analysis, potential indicators of decreased immunity increased the risk for HPV infection among older women, whereas in younger women, risk was particularly associated with sexual activity.

Promoters of and barriers to cervical cancer screening in a rural setting in Tanzania

To investigate promoters and barriers for cervical cancer screening in rural Tanzania.

Performance of visual inspection with acetic acid and human papillomavirus testing for detection of high-grade cervical lesions in HIV positive and HIV negative Tanzanian women

The aim of this cross sectional study was to assess type distribution of human papillomavirus (HPV) among HIV positive and HIV negative women who underwent cervical cancer screening, and to examine the ability of visual inspection with acetic acid (VIA), the standard detection method in Tanzania, and HPV‐testing to detect cytologically diagnosed high grade lesions or cancer (HSIL+). Women from different areas in Tanzania were invited by public announcement to cervical cancer screening organized by Ocean Road Cancer Institute (Dar‐es‐Salaam). A total of 3,767 women were enrolled. Women underwent gynecological examination with collection of cervical cells for conventional cytological examination, and swab for HPV‐DNA detection (Hybrid‐Capture2) and genotyping (LiPAv2 test). Subsequently VIA was performed. The participants were also tested for HIV. HPV16, HPV52 and HPV18 were the three most common HR HPV types among women with HSIL+ cytology with prevalences of 42.9, 35.7 and 28.6%, respectively, in HIV positive women which was higher than among HIV negative women (30.2, 21.9 and 16.7%). A total of 4.5% of the women were VIA positive, and VIA showed a low sensitivity compared to HPV‐testing for detection of HSIL+. The sensitivity of VIA varied with staff VIA experience, HIV status and age. Vaccines including HPV16, HPV52 and HPV18 will likely reduce the number of HSIL+ cases independently of HIV status. The frequency of HSIL+ was high among HIV positive women, emphasizing the importance of establishing a screening program which also reaches HIV positive women. Our results highlight the importance of continuous training of staff performing VIA, and also point to the need for other screening methods such as HPV‐testing at low cost.

Risk factors for VIA positivity and determinants of screening attendances in Dar es Salaam, Tanzania

BackgroundTanzania is among the countries in the world where the cervical cancer incidence is estimated to be highest. Acknowledging an increase in the burden of cervical cancer, VIA was implemented as a regional cervical cancer screening strategy in Tanzania in 2002. With the aim of describing risk factors for VIA positivity and determinants of screening attendances in Tanzania, this paper present the results from a comparative analysis performed among women who are reached and not reached by the screening program”.Methods14 107 women aged 25–59 enrolled in a cervical cancer screening program in Dar es Salaam in the period 2002 – 2008. The women underwent VIA examination and took part in a structured questionnaire interview. Socioeconomic characteristics, sexual behavior, HIV status and high-risk (HR) HPV infection were determined in a subpopulation of 890 who participated and 845 who did not participate in the screening.ResultsBeing widowed/separated OR=1.41 (95% CI: 1.17-1.66), of high parity OR=3.19 (95% CI: 1.84-5.48) of low education OR= 4.30 (95% CI: 3.50-5.31) and married at a young age OR=2.17 (95% CI: 1.37-3.07) were associated with being VIA positive. Women who participated in the screening were more likely to be HIV positive OR= 1.59 (95% CI. 1.14-2.25) in comparison with women who had never attended screening, while no difference was found in the prevalence of HR-HPV infection among women who had attended screening and women who had not attended screening.ConclusionWomen who are widowed/separated, of high parity, of low education and married at a young age are more likely to be VIA positive and thus at risk of developing cervical cancer. The study further documents that a referral linkage between the HIV care and treatment program and the cervical cancer screening program is in place in the setting studied, where HIV positive were more likely to participate in the cervical cancer screening program than HIV negative women.

Prevalence and Type Distribution of Human Papillomavirus Among 1813 Men in Tanzania and the Relationship to HIV Status

Background Infection with high-risk (HR) human papillomavirus (HPV) is associated with penile cancer in men, cervical cancer in women, and anal cancer and certain types of head and neck cancers in both sexes. Few studies have assessed the prevalence and type distribution of HPV among men in sub-Saharan Africa, where the rates of HIV and penile and cervical cancer are high. Material and Methods We used data from a cross-sectional study among 1813 men in Tanzania. Penile samples were tested using Hybrid Capture 2, and genotyping was done by the INNO-LiPA HPV Genotyping Extra test. Blood samples were tested for HIV. The overall and type-specific prevalence and 95% confidence interval of HPV was estimated in relation to age and HIV status. Results The overall prevalence of HPV was 20.5% (95% confidence interval, 18.7–22.4), the most prevalent HR HPV types being HPV52, HPV51, HPV16, HPV18, HPV35, and HPV66. The HR HPV prevalence was significantly higher in HIV-positive men (25.7%) than in HIV-negative men (15.8%; P = 0.0027). The prevalence of HPV16, HPV18 and multiple HR HPVs tended to be higher among HIV-positive men (statistically nonsignificant), whereas no differences were observed for the other HPV types. Conclusions We found a high prevalence of HPV types 52, 51, 16, 18, 35, and 66. This information is of relevance in the understanding of HPV type distributions across populations. Although the prevalence of HPV16 and HPV18 was slightly higher among HIV-positive men, our results indicate that HIV status does not strongly influence the distribution of HPV types. Therefore, the currently available HPV vaccines could prevent HPV infection independently of HIV status.

Clinical and epidemiologic variations of esophageal cancer in Tanzania.

AIM To estimate the incidence of esophageal cancer (EC) in Kilimanjaro in comparison to other regions in Tanzania. METHODS We also examined the clinical, epidemiologic, and geographic distribution of the 1332 EC patients diagnosed and/or treated at Ocean Road Cancer Institute (ORCI) during the period 2006-2013. Medical records were used to abstract patient information on age, sex, residence, smoking status, alcohol consumption, tumor site, histopathologic type of tumor, date and place of diagnosis, and type and date of treatment at ORCI. Regional variation of EC patients was investigated at the level of the 26 administrative regions of Tanzania. Total, age- and sex-specific incidence rates were calculated. RESULTS Male patients 55 years and older had higher incidence of EC than female and younger patients. Of histopathologically-confirmed cases, squamous-cell carcinoma represented 90.9% of histopathologic types of tumors. The administrative regions in the central and eastern parts of Tanzania had higher incidence rates than western regions, specifically administrative regions of Kilimanjaro, Dar es Salaam, and Tanga had the highest rates. CONCLUSION Further research should focus on investigating possible etiologic factors for EC in regions with high incidence in Tanzania.

Cost-Effectiveness of Screening and Treatment for Cervical Cancer in Tanzania: Implications for other Sub-Saharan African Countries

OBJECTIVES To compare the institutional cost per person of screening and treatment between two groups of patients-those screened and those not screened before treatment for cervical cancer at Ocean Road Cancer Institute (ORCI) in Dar es Salaam, Tanzania-and to perform a cost-effectiveness analysis of the ORCI cervical cancer screening program. METHODS The study included 721 screened and 333 unscreened patients treated at ORCI for cervical cancer from 2002 to 2011. We compared the cost of cervical cancer treatment per patient with life-years gained for patients screened at ORCI versus not screened. RESULTS Patients with cancer were diagnosed at an earlier stage after participating in screening compared with nonparticipants. For example, 14.0% of stage I cancer patients had received screening by ORCI compared with 7.8% of unscreened cases. For stage IV cancer, these percentages were 1.4% and 6.9%, respectively. Average screening and treatment cost for patients receiving cancer screening (