From the Guidelines
Individuals with schizophrenia are at a higher risk of developing certain types of cancer, including lung, breast, and colorectal cancer, due to a combination of lifestyle factors, medication effects, and healthcare disparities. The association between schizophrenia and cancer risk is complex and multifaceted, involving factors such as higher smoking rates, poor diet, obesity, and sedentary behavior, as well as the potential effects of antipsychotic medications on cancer susceptibility 1.
Cancer Risk Patterns in Schizophrenia
- Lung cancer: higher rates among people with schizophrenia, primarily due to higher smoking rates in this population
- Breast cancer: more common, possibly related to elevated prolactin levels from antipsychotic medications
- Colorectal cancer: increased incidence, potentially due to lifestyle factors like poor diet, obesity, and sedentary behavior
- Prostate cancer: less frequent in men with schizophrenia, which may be linked to the antidopaminergic effects of antipsychotic medications
- Melanoma: lower rates, though the reasons remain unclear
Importance of Cancer Screening
Regular cancer screening is especially important for schizophrenia patients, with particular attention to lung, breast, and colorectal cancer surveillance 1. Patients with schizophrenia should be encouraged to undergo recommended age- and sex-appropriate cancer screenings and to reduce their modifiable cancer risk factors, such as obesity, physical inactivity, and smoking.
Healthcare Disparities and Cancer Risk
Healthcare disparities, including delayed cancer screening and diagnosis, may also contribute to the increased cancer risk in individuals with schizophrenia 1. Therefore, it is essential to address these disparities and ensure that individuals with schizophrenia receive comprehensive medical care, including regular cancer screening and health promotion interventions.
From the Research
Cancers Associated with Schizophrenia
- The relationship between schizophrenia and cancer incidence is complex, with some studies suggesting an increased risk of certain types of cancer, while others find no overall higher cancer risk 2, 3, 4.
- Specific cancers that have been associated with schizophrenia include:
- Colon cancer: a 190% increased risk (adjusted OR, 2.90; 95% CI, 1.85-4.57) 2, and a 308% increased risk in patients taking antipsychotics (adjusted OR, 4.08; 95% CI, 2.43-6.84) 2.
- Breast cancer: a marginal increased risk (adjusted OR, 1.52; 95% CI, 1.10-2.11) 2, and a significantly increased risk in women with schizophrenia (SIR, 1.31; 95% CI, 1.14-1.50; P < .001) 5.
- Lung cancer: a higher risk (IRR 1.42,95% CI 1.28-1.58) 3, and increased mortality 4.
- Oesophageal cancer: a higher risk (IRR 1.25,95% CI 1.07-1.46) 3.
- Pancreatic cancer: a higher risk (IRR 1.10,95% CI 1.01-1.21) 3.
- Some studies have also found a lower risk of certain cancers, such as prostate cancer (IRR 0.66,95% CI 0.55-0.79) 3.
- Disruptions in cancer care are common for patients with schizophrenia, and are associated with adverse outcomes, including cancer recurrence 6.
- Access to psychiatric treatment at cancer diagnosis may protect against critical disruptions in cancer care for this underserved population 6.