Moving towards a strategy to accelerate cervical cancer elimination in a high-burden city-Lessons learned from the Amazon city of Manaus, Brazil

Abstract

The World Health Organization Call to Eliminate Cervical Cancer resonates in cities like Manaus, Brazil, where the burden is among the world's highest. Manaus has offered free cytology-based screening since 1990 and HPV immunization since 2013, but the public system is constrained by many challenges and performance is not well-defined. We obtained cervical cancer prevention activities within Manaus public health records for 2019 to evaluate immunization and screening coverage, screening by region and neighborhood, and the annual Pink October screening campaign. We estimated that among girls and boys age 14-18, 85.9% and 64.9% had 1+ doses of HPV vaccine, higher than rates for age 9-13 (73.4% and 43.3%, respectively). Of the 90,209 cytology tests performed, 24.9% were outside the target age and the remaining 72,230 corresponded to 40.1% of the target population (one-third of women age 25-64). The East zone had highest screening coverage (49.1%), highest high-grade cytology rate (2.5%) and lowest estimated cancers (38.1/100,000) compared with the South zone (32.9%, 1.8% and 48.5/100,000, respectively). Largest neighborhoods had fewer per capita screening locations, resulting in lower coverage. During October, some clinics successfully achieved higher screening volumes and high-grade cytology rates (up to 15.4%). Although we found evidence of some follow-up within 10 months post-screening for 51/70 women (72.9%) with high-grade or worse cytology, only 18 had complete work-up confirmed. Manaus has successfully initiated HPV vaccination, forecasting substantial cervical cancer reductions by 2050. With concerted efforts during campaigns, some clinics improved screening coverage and reached high-risk women. Screening campaigns in community locations in high-risk neighborhoods using self-collected HPV testing can achieve widespread coverage. Simplifying triage and treatment with fewer visits closer to communities would greatly improve follow-up and program effectiveness. Achieving WHO Cervical Cancer Elimination goals in high-burden cities will require major reforms for screening and simpler follow-up and treatment.

Fig 1. Approximate annual screening coverage among women age 25–64, Manaus, Brazil, 2010–2019.

Approximate coverage = Number of cytology tests (screening and follow-up) processed at public laboratory among target population (1/3 of women age 25–64 in Manaus). Data sources: 2010 to 2013: SISCOLO / DATASUS; 2014 to 2016: SISCOLO-AM / DPCC (Local system). 2017 to 2018: SUS Outpatient Information System (SIA / SUS); 2019: Manaus Cytopathology Laboratory -SEMSA- Manaus (considering only Pap tests for screening).

Fig 2. Female population age 25–64, screening units, coverage per residential neighborhoods in urban Manaus, Brazil, 2019.

Estimated female population is represented by size of dots. Colors are used only to distinguish screening units. Dots on the x-axis indicate neighborhoods without screening units and their population uses units from nearby neighborhoods. *Some screening units attend to women who reside outside the area, at times resulting in coverage estimates of greater than 100% (particularly for smaller units).

Fig 3. Clinical follow-up and results for women with high-grade cytology result in Manaus, Brazil.

ASC-H: Atypical squamous cells, cannot rule-out high-grade squamous intraepithelial lesion; AGC: Atypical glandular cells; HSIL: High-grade squamous intraepithelial lesion; SCC: Squamous cell carcinoma. CIN1≤: Grade I Cervical Intraepithelial neoplasia, chronic cervicitis with squamous metaplasia and Ectocervix without significant histological changes. CIN2 ≥ (Grade II Cervical Intraepithelial Neoplasia, Grade III Cervical Intraepithelial Neoplasia). Months between cytology and colposcopy/biopsy: mean = 4.17 months, median = 2 months.