The key objective of the Screening Group is to generate evidence about the accuracy, reproducibility, efficacy, benefits, harmful effects, and cost–effectiveness of various early detection interventions for breast, cervical, colorectal, and oral cancers, among others, in reducing deaths and improving patients′ quality of life in various settings.
Screening aims to reduce the incidence of and/or deaths from cancer by detecting early preclinical disease, for which treatment may be simpler and more effective than for advanced cancer diagnosed after the symptoms appear. Educating the population about the early symptoms of common cancers and ensuring access to prompt and appropriate diagnosis and treatment is also a well-recognized approach (“clinical early diagnosis”) to early detection of cancer.
For screening to be effective, the screening programme should be well organized and ensure high coverage of the eligible population; must incorporate a screening test that is accurate, feasible, affordable, culturally acceptable, and safe; should provide prompt diagnostic, treatment, and follow-up services to those with positive screening tests; and should ensure the quality at every step. Hence, screening programmes require significant human and financial resources. Screening also has its own undesired harmful effects, due to false-positive results leading to high levels of anxiety and unnecessary investigations and treatment, and false-negative results leading to false reassurance. To minimize the harms and increase the benefits of screening, the services should be evidence-based, quality-assured, and equitably distributed.
It is important to evaluate the effectiveness of a new screening method in reducing the disease burden, as well as its overall cost–effectiveness, before it is considered for widespread implementation in large population settings. The technologies proven to be effective in high-resource settings may not be feasible and/or affordable in low- and middle-income countries (LMICs), and alternative solutions may be needed to tackle the cancer burden in such settings. A major focus of the Screening Group is to identify and evaluate alternative solutions to the growing cancer burden in LMICs. These are not limited to screening technologies but also include simple treatment methods and vaccination against human papillomavirus. The ultimate goal of the Screening Group′s research initiatives is to catalyse the widespread implementation of feasible and cost-effective screening programmes in LMICs.