?Background:
Population screening for the early detection of cancer often relies on radiologic imaging and thus involves exposure to ionizing radiation. In asymptomatic individuals, this requires a particularly careful evaluation of the balance between the potential benefits and the radiation-associated risks. In accordance with the European Union Basic Safety Standards Directive, the German Radiation Protection Act requires that such early detection examinations be authorized by statutory ordinance. This authorization is based on a scientific assessment of benefits, adverse effects, and associated radiation risks, prepared by the Federal Office for Radiation Protection (BfS).
Objectives:
This contribution aims to describe the scientific framework used to assess the benefit-risk balance for cancer screening examinations involving ionizing radiation, focusing on low-dose computed tomography (LDCT) for lung cancer screening as an example. It further illustrates how systematic evidence assessment informs regulatory decision-making and supports the safe and effective application of radiological screening in asymptomatic individuals.
Methods:
The scientific evaluation by the BfS is based on a systematic review of available data from clinical evidence, esp. randomized controlled studies, combined with an assessment of the radiation-related risk. Key factors assessed include the effectiveness of screening in reducing disease-related mortality and the lifetime attributable risk associated with radiation exposure. Additionally, conditions and requirements are defined that are to be placed so that the benefit outweighs the potential adverse effects such as overdiagnosis and false-positive findings and the radiation risk.
Results:
In the case of lung cancer early detection through LDCT, the BfS concluded that the expected benefits outweigh the associated risks, leading to a positive benefit-risk profile when strict conditions for the implementation of the screening are applied. Based on this, formal approval was granted. Conditions cover aspects such as the target population, screening intervals, quality assurance, and imaging protocols to minimize radiation exposure and reduce false-positive findings. As a result, low-dose CT screening for lung cancer will be incorporated into the German healthcare system for statutory insured individuals by mid-2026.
Conclusion:
Rigorous scientific evaluation of cancer screening procedures using ionizing radiation is essential for protecting public health, particularly when screening asymptomatic individuals. The example of LDCT for lung cancer screening in Germany demonstrates how a structured benefit-risk assessment can guide regulatory decisions and implementation. Similar evaluation approaches are applied to other radiological cancer screenings, like the extension of the age limits in the German mammography screening program, highlighting the broader relevance of this framework for evidence-based cancer screening.