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Summary of studies suggesting that social supports are associated with clinic outcomes in cancer.

Key findings suggesting an association between social support and clinical outcome in cancer
Cancer survival
Social isolation and loneliness are associated with an increased risk of risk of all-cause mortality, and increased risk of cancer mortality (meta-analysis of 90 prospective cohort studies, including >2 million adults)10 Higher perceived social support associated with 60% lower odds of death (study of 568 patients with gastrointestinal cancers)14
Cancer recurrence
The After Breast Cancer Pooling Project demonstrated higher rates of both cancer recurrence and breast cancer-specific mortality in more socially isolated women (study of 9267 patients with breast cancer)12
Quality of life
Higher perceived social support found to be associated with lower depressive symptoms and higher health-related quality of life (study of 1818 patients with cancer15 Social support positively predictive of better physical and mental health-related quality of life (study of 412 patients with breast cancer)16
Likelihood of cancer treatment
Patients with 2 or more support sources had higher odds of undergoing chemotherapy than those without social support (cross-sectional survey of 1087 adults with colon cancer)17
Hospital readmission
Limited social support associated with increased likelihood of hospital readmission within 90 days of index hospitalization discharge (study of >200 patients with hematological malignancies)18
Cancer incidence
Social isolation found to be associated with total cancer incidence later in life. Loneliness specifically, was associated with lung cancer incidence (Finnish longitudinal study of 2570 middle-aged men, mean follow-up: 20.44 years)19