Environmental determinants of cancer outcomes: a scoping review

As cancer care evolves toward more individualized, survivorship-focused models, there is growing interest in the role of non-biological factors that shape outcomes after diagnosis. Environmental exposures, ranging from air pollution to urban infrastructure, are increasingly recognized as modifiable contributors not only to cancer incidence but also to outcomes after diagnosis. Yet, evidence on cancer outcomes remains fragmented. We conducted a scoping review to map existing literature on the relationship between environmental factors and cancer outcomes, including mortality, treatment-related toxicity, and health-related quality of life. Air pollution was extensively studied, with consistent associations with poorer lung cancer outcomes and emerging evidence for other cancers. Radon was another common exposure investigated, largely in relation to lung cancer. Other factors such as proximity to industrial sites, chemical pollutants, green space access, noise, and meteorological conditions were less frequently examined. Most studies focused on mortality, with limited attention to quality of life or treatment-related complications. Moreover, because many studies were ecological and/or did not model exposure timing relative to diagnosis and treatment, the literature often cannot separate increased cancer mortality driven by higher incidence from worse prognosis after diagnosis. Evidence directly addressing peri-treatment exposures, treatment tolerance/toxicity, and survivorship-specific outcomes remains sparse. Research was concentrated in high-income countries, while evidence from low- and middle-income regions was limited. This review highlights emerging mechanisms, data challenges, and opportunities for translational research and policy intervention, while underscoring the need for interdisciplinary, equity-focused approaches to strengthen causal inference and guide public health strategies.