The theory that there is a "cancer personality" that increases breast cancer risk and reduces survival has been circulating in popular culture for decades. Books such as The Type C Connection: The Behavioral Links to Cancer and Your Health (1992) have been followed by more recent books such as Healing the Cancer Personality (2013).
However, while there is some limited evidence linking extremely severe stress and breast cancer risk, researchers generally have found no significant associations between personality traits and breast cancer risk or prognosis. Now a new study has again found no significant associations between personality and breast cancer risk or survival.
There is no cancer personality
As noted above, the theory that there is a cancer personality that predisposes women to breast cancer has not been borne out in the numerous studies that have been undertaken to study it. The following personality traits have been ruled out as contributing to the risk of developing breast cancer:
- Emotional repression
- Chronic anxiety
- Introversion or extraversion
- Anti-emotionality (an absence of emotional behavior or a lack of trust in one’s own feelings)
- Anger control (whether a lack of control or too much control)
- Hostility or Type A behavior
- Cynical distrust
- Style of coping behavior
- Openness to experience
- Joint effect of personality traits making up a proposed "cancer personality" (variously described, but typically including passive, emotionally inexpressive, conforming and unassertive traits).
Latest research finds personality and breast cancer not linked
The prospective study referenced at the beginning of this news story was designed to investigate whether personality is associated with breast cancer risk or survival. The study included 15,107 Japanese women aged 40 to 64 who completed the Eysenck Personality Questionnaire-Revised (EPQ-R) Short Form at enrollment. The women, who were cancer-free initially, were followed from 1990 to 2007.
Study participants were divided into quartiles for each EPQ-R subscale (extraversion, neuroticism, psychoticism, and lie) based on their scores. The analysis for each subscale was computed using the lowest quartile as reference. No association was found between any of the four personality subscales and breast cancer risk.
To investigate whether personality influences survival after breast cancer, the authors followed 250 of the women who developed breast cancer from diagnosis through 2008. A total of 45 of these women died during follow up (this included deaths from all causes, not just breast cancer). No significant associations were found between any of the personality subscales and risk of death. Women with a higher score of extraversion tended to have a lower risk of death, although this result was not statistically significant. The authors also performed the analyses excluding the 32 women diagnosed during the first three years of follow up. However, this did not essentially change the results with respect to either breast cancer risk or survival.
The authors conclude that personality does not appear to significantly impact the development or progression of breast cancer.
Selected breast cancer studies
Posttraumatic stress disorder and cancer risk: a nationwide cohort study
Gradus JL, Farkas DK, Svensson E, Ehrenstein V, Lash TL, Milstein A, et al. Posttraumatic stress disorder and cancer risk: a nationwide cohort study. European Journal of Epidemiology. Springer Science and Business Media LLC; 2015; 30:563-568 10.1007/s10654-015-0032-7
Depression and Antidepressant Use in Relation to Breast Cancer Risk in the Nurses Health Study
Reeves K, Okereke O, Qian J, Hankinson S. Depression and Antidepressant Use in Relation to Breast Cancer Risk in the Nurses Health Study. Cancer Epidemiology Biomarkers & Prevention. American Association for Cancer Research (AACR); 2015; 24:761.3-762 10.1158/1055-9965.epi-15-0107
Is personality associated with cancer incidence and mortality? An individual-participant meta-analysis of 2156 incident cancer cases among 42 843 men and women
Jokela M, Batty GD, Hintsa T, Elovainio M, Hakulinen C, Kivimäki M. Is personality associated with cancer incidence and mortality? An individual-participant meta-analysis of 2156 incident cancer cases among 42 843 men and women. British Journal of Cancer. Springer Science and Business Media LLC; 2014; 110:1820-1824 10.1038/bjc.2014.58
Chronic Social Isolation Is Associated with Metabolic Gene Expression Changes Specific to Mammary Adipose Tissue
Volden PA, Wonder EL, Skor MN, Carmean CM, Patel FN, Ye H, et al. Chronic Social Isolation Is Associated with Metabolic Gene Expression Changes Specific to Mammary Adipose Tissue. Cancer Prevention Research. American Association for Cancer Research (AACR); 2013; 6:634-645 10.1158/1940-6207.capr-12-0458
Personality Traits and Cancer Risk and Survival Based on Finnish and Swedish Registry Data
Nakaya N, Bidstrup PE, Saito-Nakaya K, Frederiksen K, Koskenvuo M, Pukkala E, et al. Personality Traits and Cancer Risk and Survival Based on Finnish and Swedish Registry Data. American Journal of Epidemiology. Oxford University Press (OUP); 2010; 172:377-385 10.1093/aje/kwq046
Mental Vulnerability and Survival After Cancer
Nakaya N, Bidstrup PE, Eplov LF, Saito-Nakaya K, Kuriyama S, Tsuji I, et al. Mental Vulnerability and Survival After Cancer. Epidemiology. Ovid Technologies (Wolters Kluwer Health); 2009; 20:916-920 10.1097/ede.0b013e3181b5f3b0
Personality Factors and Breast Cancer Risk: A 13-Year Follow-up
Bleiker EMA, Hendriks JHCL, Otten JDM, Verbeek ALM, van der Ploeg HM. Personality Factors and Breast Cancer Risk: A 13-Year Follow-up. JNCI: Journal of the National Cancer Institute. Oxford University Press (OUP); 2008; 100:213-218 10.1093/jnci/djm280