Is stroke incidence increased in survivors of adult cancers? A systematic review and meta-analysis

Purpose Existing research hints that people living with and beyond cancer are at an increased risk of stroke. However, there is insufficient evidence to appropriately inform guidelines for specific stroke prevention or management for cancer patients. We conducted a systematic review and meta-analysis to describe and quantify stroke incidence in people living with and beyond cancer. Methods Medline, CINAHL, and EMBASE were searched for epidemiological studies comparing stroke incidence between cancer and non-cancer patients. Reviewers independently extracted data; random-effects meta-analyses and quality assessment were performed. Results Thirty-six studies were narratively synthesised. Meta-analysis was conducted using seven studies. Methodological quality was high for most studies. Study populations were heterogeneous, and the length of follow-up and risk factors varied. There was a variation in risk between different cancer types and according to stroke type: pancreatic (HR 2.85 (95% CI 2.43–3.36), ischaemic) (HR 2.28 (95% CI 1.43–3.63), haemorrhagic); lung (HR 2.33 (95% CI 1.63–3.35), ischaemic) (HR 2.14 (95% CI 1.45–3.15), haemorrhagic); and head and neck (HR 1.54 (95% CI 1.40–1.69), haemorrhagic) cancers were associated with significantly increased incidence of stroke. Risk is highest within the first 6 months of diagnosis. Narrative synthesis indicated that several studies also showed significantly increased incidence of stroke in individuals with colorectal cancer, breast cancer, ovarian cancer, nasopharyngeal cancer, leukaemia, and myeloma, and those who have received radiotherapy for head and neck cancers and platinum-based chemotherapy may also have higher stroke incidence. Conclusions Stroke incidence is significantly increased after diagnosis of certain cancers. Implications for Cancer Survivors Cardiovascular risk should be assessed during cancer survivorship care, with attention to modifying shared cancer/cardiovascular risk factors.