Objectives Cervical cancer is increasing but underestimated in developing countries. We calculated the observed and expected incidence of cervical cancer in Lusaka and Southern and Western provinces of Zambia. Methods/Materials Data for 2007-2012 was obtained for the 3 provinces. Data included age, residence, year of diagnosis, marital status, occupation, HIV, stage, radiotherapy and chemotherapy. Expected incidence in Southern and Western provinces was calculated based on observed incidence for Lusaka province, adjusting for HIV. Results Crude and age-standardized incidence rates (ASR) in Lusaka were 2-4 times higher than incidence in the other 2 provinces. Lusaka had a rate of 54.1/105 and ASR of 82.1/105 in the age group 15-49. The Southern province had a rate of 17.1/105 and ASR of 25.5/105; Western province rate of 12.3/105 and ASR rate of 17.2/105. The observed cervical cancer incidence rates in the Southern and Western provinces were lower than the rate in Lusaka, possibly due to the uncertainty of underreporting/under-diagnosis or actual lower risk for reasons yet unclear. HIV seroprevalence rate in patients from the 3 provinces were 46 – 93% higher than seroprevalence in the respective general populations. Conclusion Cervical cancer is significantly underestimated in Zambia and HIV has a significant role in pathogenesis. Future studies should establish methods for case ascertainment and better utilization of hospital- and population-based registries in Zambia and other similar developing countries.

IntroductionSub-Saharan Africa has the highest global incidence of cervical cancer. Cervical cancer is the most common cause of cancer morbidity and mortality among women in Zambia. HIV increases the risk for cervical cancer and with a national Zambian adult HIV prevalence of 16%, it is important to investigate the impact of HIV on the progression of cervical cancer. We measured differences in cervical cancer progression between HIV-positive and HIV-negative patients in Zambia.MethodsThis study included 577 stage I and II cervical cancer patients seen between January 2008 and December 2012 at the Cancer Diseases Hospital in Lusaka, Zambia. The inclusion criteria for records during the study period included known HIV status and FIGO stage I and II cervical cancer at initial date of registration in the Cancer Diseases Hospital. Medical records were abstracted for clinical and epidemiological data. Cancer databases were linked to the national HIV database to assess HIV status among cervical cancer patients. Logistic regression examined the association between HIV and progression, which was defined as metastatic or residual tumor after 3 months of initial treatment.ResultsA total of 2451 cervical cancer cases were identified, and after exclusion criteria were performed the final analysis population totaled 537 patients with stage I and II cervical cancer with known HIV status (224 HIV-positive and 313 HIV-negative). HIV-positive women were, on average, 10 years younger than HIV-negative women who had a median age of 42, ranging between 25 and 72. A total of 416 (77.5%) patients received external beam radiation, and only 249 (46.4%) patients received the recommended treatment of chemotherapy, external beam radiation, and brachytherapy. Most patients were stage II (85.7%) and had squamous cell carcinoma (74.7%). HIV-positive patients were more likely to receive lower doses of external beam radiation than HIV-negative patients (47% vs 37%; P<0.05, respectively). The median total dose of external beam radiation for HIV-positive and HIV-negative patients was 46 Gy and 50 Gy, respectively. HIV positivity did not lead to tumor progression (25.4% in HIV-positive vs 23.9% in HIV-negative, OR 1.04, 95% CI [0.57, 1.92]). However, among a subset of HIV-positive patients, longer duration of infection was associated with lower odds of progression.ConclusionThere was no significant impact on non-metastatic cervical cancer progression by HIV status among patients in Lusaka, Zambia. The high prevalence of HIV among cervical cancer patients suggest that HIV-positive patients should be a primary target group for HPV vaccinations, screening, and early detection.

Cervical cancer is the fourth most commonly diagnosed cancer and fourth leading cause of cancer death among women globally. 1 There were an estimated 570 000 cervical cancer cases and 311 000 deaths worldwide in 2018. [1][2][3] In low-resource countries, cervical cancer is the second most diagnosed and second leading cause of cancer mortality. 1,4 In Zambia, the cervical cancer incidence rate of about 43.1 per 100 000 per year and mortality of 20.0 per 100 000 per year are among the highest in the world. 1,3,5 HPV is the main causal agent of cervical cancer. HPV is responsible for 99.7% of all cervical carcinomas with high-risk HPV types 16 and 18 accounting for 75% of all cases. 4 The high-risk HPV oncogenic types 16 and 18 each has a prevalence of 21.6% in Zambia. 6