Schizophrenia, Antipsychotic Drugs, and Risk of Breast Cancer.

Abstract

Breast cancer is the commonest form of cancer among women. Literature suggests that women with schizophrenia are less likely to be screened for breast cancer and that, among women with schizophrenia who develop breast cancer, mortality rates are higher. This article examines recent meta-analyses and recent observational studies on the risk of breast cancer in women with schizophrenia, especially in the context of treatment with first generation and second generation antipsychotic (FGA, SGA) drugs. This article also examines the most recent observational study in detail to help readers better understand how to critically appraise this and, by extension, other studies in the field. In summary, studies in the field suggest that there is a small but statistically significant increase in the risk of breast cancer in women with schizophrenia relative to women without psychiatric disorders as well as relative to women with other psychiatric disorders. Women who appear to be most at risk are those in the perimenopausal age range and those with several years of exposure to FGA or prolactin raising antipsychotics. Whereas the possibility of residual confounding in observational studies precludes ascribing a causal role for antipsychotics, given that FGA and prolactin-raising SGA are associated with other adverse effects, it seems reasonable, wherever possible, to prefer SGA over FGA, and prolactin-sparing over prolactin-raising antipsychotics. Women with schizophrenia, and especially those who use prolactin raising antipsychotics for long periods, should be monitored for the risk of breast cancer as a special part of monitoring general health; and modifiable risk factors for breast cancer should be addressed through appropriate behavioral and pharmacological interventions. Women with schizophrenia comprise a vulnerable population, and their medical health should not be neglected even when caring for their mental health absorbs attention and time. Suggestions are provided for directions for future research.