Background
Tobacco use is strongly associated with cancer, with more than 60 carcinogens in tobacco smoke contributing to malignancies of the lung and at least 16 other cancer sites. Smoking cessation provides immediate and long-term benefits, including improved oxygenation, immune response, psychological well-being, and treatment tolerance. Despite clear evidence that cessation after a cancer diagnosis improves outcomes, up to 50% of patients who smoke at diagnosis continue during treatment. Smoking cessation therefore represents a critical, yet underutilised, opportunity to improve cancer outcomes, requiring stronger alignment between scientific evidence, clinical practice, and policy.
Methods
In 2022, an international Smoking Cessation and Cancer Working Group was established to strengthen the science–policy interface and accelerate the integration of smoking cessation into standard oncologic care. The group brings together researchers, statisticians, clinicians, public health experts, tobacco control specialists, and patient representatives from Europe, North America, and international organisations, including WHO and IARC. Coordinated by Cancer Patients Europe, the collaboration is structured around regular meetings to share updates, exchange ideas, review emerging evidence, and align research and advocacy priorities, with a specific focus on smoking cessation interventions, including after a cancer diagnosis.
Results
Since its inception, the group has acted as a global network to generate, share, and amplify evidence on smoking cessation in cancer care. Early outputs included scientific and policy-focused sessions at the UICC World Cancer Congress and the ENSP Conference in 2022, followed by continued engagement at the ENSP Conference 2023 and the World Cancer Congress 2024. These exchanges have catalysed concrete initiatives, including research projects and ongoing work in Italy and the US. Notably, the US-based effort includes an NCI-funded SUMMIT initiative focused on scaling up and sustaining smoking cessation interventions for cancer patients. Across initiatives in Europe, Canada, and the USA, evidence highlights that pharmacological interventions combined with behavioural and cognitive support offer the most effective approach for long-term cessation, with prognostic benefits comparable to improvements in cancer stage in some settings.
Conclusions
This collaboration illustrates how sustained, multidisciplinary engagement can bridge science and policy to address a persistent gap in cancer care. By aligning research evidence, clinical expertise, patient perspectives, and advocacy, the group contributes to repositioning smoking cessation as a first-line component of oncologic treatment rather than an optional supportive measure. Integrating smoking cessation interventions into standard cancer care pathways is essential to improving outcomes and advancing equitable, evidence-based cancer control globally.