National Cancer Control Program, Ministry of Health, Nairobi, Kenya.
Clinton Health Access Initiative, Nairobi, Kenya.
PLoS One. 2023 May 25;18(5):e0286202. doi: 10.1371/journal.pone.0286202. eCollection 2023.
Globally, cervical cancer is a major public health problem, with about 604,000 new cases and over 340,000 deaths in 2020. In Kenya, it is the leading cause of cancer deaths, with over 3,000 women dying in 2020 alone. Both the Kenyan cancer screening guidelines and the World Health Organization's Global Cervical Cancer Elimination Strategy recommend human papillomavirus (HPV) testing as the primary screening test. However, HPV testing is not widely available in the public healthcare system in Kenya. We conducted a pilot study using a point of care (POC) HPV test to inform national roll-out.
The pilot was implemented from October 2019 to December 2020, in nine health facilities across six counties. We utilized the GeneXpert platform (Cepheid, Sunnyvale, CA, USA), currently used for TB, Viral load testing and early infant diagnosis for HIV, for HPV screening. Visual inspection with acetic acid (VIA) was used for triage of HPV-positive women, as recommended in national guidelines. Quality assurance (QA) was performed by the National Oncology Reference Laboratory (NORL), using the COBAS 4800 platform (Roche Molecular System, Pleasanton, CF, USA). HPV testing was done using either self or clinician-collected samples. We assessed the following screening performance indicators: screening coverage, screen test positivity, triage compliance, triage positivity and treatment compliance. Test agreement between local GeneXpert and central comparator high-risk HPV (hrHPV) testing for a random set of specimens was calculated as overall concordance and kappa value. We conducted a final evaluation and applied the Nominal Group Technique (NGT) to identify implementation challenges and opportunities.
The screening coverage of target population was 27.0% (4500/16,666); 52.8% (2376/4500) were between 30-49 years of age. HPV positivity rate was 22.8% (1027/4500). Only 10% (105/1027) of HPV positive cases were triaged with VIA/VILI; 21% (22/105) tested VIA/VILI positive, and 73% (16/22) received treatment (15 received cryotherapy, 1 was referred for biopsy). The median HPV testing turnaround time (TAT) was 24 hours (IQR 2-48 hours). Invalid sample rate was 2.0% (91/4500). Concordance between the Cepheid and COBAS was 86.2% (kappa value = 0.71). Of 1042 healthcare workers, only 5.6% (58/1042) were trained in cervical cancer screening and treatment, and only 69% (40/58) of those trained were stationed at service provision areas. Testing capacity was identifed as the main challenge, while the community strategy was the main opportunity.
HPV testing can be performed on GeneXpert as a near point of care platform. However, triage compliance and testing TAT were major concerns. We recommend strengthening of the screening-triage-treatment cascade and expansion of testing capacity, before adoption of a GeneXpert-based HPV screening among other near point of care platforms in Kenya.
在全球范围内,宫颈癌是一个主要的公共卫生问题,2020 年全球有大约 60.4 万例新发病例和 34 万多例死亡病例。在肯尼亚,宫颈癌是癌症死亡的主要原因,仅 2020 年就有 3000 多名妇女死亡。肯尼亚癌症筛查指南和世界卫生组织全球消除宫颈癌战略都建议使用人乳头瘤病毒(HPV)检测作为主要筛查检测方法。然而,HPV 检测在肯尼亚的公共医疗体系中并不广泛应用。我们进行了一项试点研究,使用即时检测(POC)HPV 检测为全国推广提供信息。
该试点于 2019 年 10 月至 2020 年 12 月在肯尼亚六个县的九个卫生机构实施。我们利用 GeneXpert 平台(Cepheid,加利福尼亚州桑尼维尔),目前用于结核病、病毒载量检测和艾滋病毒早期婴儿诊断,进行 HPV 筛查。醋酸视觉检查(VIA)用于 HPV 阳性妇女的分流,如国家指南所建议。国家肿瘤学参考实验室(NORL)使用 COBAS 4800 平台(罗氏分子系统,加利福尼亚州普莱森顿)进行质量保证(QA)。HPV 检测可以由患者自己或临床医生采集样本进行。我们评估了以下筛查性能指标:筛查覆盖率、筛查检测阳性率、分流依从性、分流阳性率和治疗依从性。随机抽取一组标本,使用本地 GeneXpert 和中央比较器高危型 HPV(hrHPV)检测进行了测试一致性评估,计算了总体一致性和kappa 值。我们进行了最终评估,并采用名义群体技术(NGT)确定实施挑战和机会。
目标人群的筛查覆盖率为 27.0%(4500/16666);52.8%(2376/4500)年龄在 30-49 岁之间。HPV 阳性率为 22.8%(1027/4500)。只有 10%(105/1027)的 HPV 阳性病例接受了 VIA/VILI 分流;21%(22/105)的 VIA/VILI 检测阳性,73%(16/22)接受了治疗(15 人接受了冷冻治疗,1 人被转诊进行活检)。HPV 检测的中位周转时间(TAT)为 24 小时(IQR 2-48 小时)。无效样本率为 2.0%(91/4500)。Cepheid 和 COBAS 之间的一致性为 86.2%(kappa 值=0.71)。在 1042 名卫生工作者中,只有 5.6%(58/1042)接受过宫颈癌筛查和治疗培训,接受过培训的人中只有 69%(40/58)在服务提供地区工作。检测能力是主要挑战,而社区策略是主要机遇。
可以在 GeneXpert 上进行 HPV 检测作为接近即时检测的平台。然而,分流依从性和检测 TAT 是主要关注点。我们建议在肯尼亚其他接近即时检测的 HPV 筛查平台之前,加强筛查-分流-治疗的级联,并扩大检测能力。