Breast cancer is the most common cancer affecting women worldwide. It is a distressing diagnosis and, as a result, considerable research has examined the psychological sequelae of being diagnosed and treated for breast cancer. Breast cancer is associated with increased rates of depression and anxiety and reduced quality of life. As a consequence, multiple studies have explored the impact of psychological interventions on the psychological distress experienced after a diagnosis of breast cancer.
To assess the effects of psychological interventions on psychological morbidities, quality of life and survival among women with non-metastatic breast cancer.
We searched the following databases up to 16 May 2013: the Cochrane Breast Cancer Group Specialised Register, CENTRAL, MEDLINE, EMBASE, CINAHL and PsycINFO; and reference lists of articles. We also searched the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP) search portal and ClinicalTrials.gov for ongoing trials in addition to handsearching.
Randomised controlled trials that assessed the effectiveness of psychological interventions for non-metastatic breast cancer in women.
Two review authors independently appraised and extracted data from eligible trials. Any disagreement was resolved by discussion. Extracted data included information about participants, methods, the intervention and outcome.
Twenty-eight randomised controlled trials comprising 3940 participants were included. The most frequent reasons for exclusion were non-randomised trials and the inclusion of women with metastatic disease. A wide range of interventions were evaluated, with 24 trials investigating a cognitive behavioural therapy and four trials investigating psychotherapy compared to control. Pooled standardised mean differences (SMD) from baseline indicated less depression (SMD -1.01, 95% confidence interval (CI) -1.83 to -0.18; P = 0.02; 7 studies, 637 participants, I(2) = 95%, low quality evidence), anxiety (SMD -0.48, 95% CI -0.76 to -0.21; P = 0.0006; 8 studies, 776 participants, I(2) = 64%, low quality evidence) and mood disturbance (SMD -0.28, 95% CI -0.43 to -0.13; P = 0.0003; 8 studies, 1536 participants, I(2) = 47%, moderate quality evidence) for the cognitive behavioural therapy group than the control group. For quality of life, only an individually-delivered cognitive behavioural intervention showed significantly better quality of life than the control with an SMD of 0.65 (95% CI 0.07 to 1.23; P = 0.03; 3 studies, 141 participants, I(2) = 41%, very low quality evidence). Pooled data from two group-delivered studies showed a non-significant overall survival benefit favouring cognitive behavioural therapy compared to control (pooled hazard ratio (HR) 0.76, 95% CI 0.25 to 2.32; P = 0.63; 530 participants, I(2) = 84%, low quality evidence). Four studies compared psychotherapy to control with one to two studies reporting on each outcome. The four studies were assessed as high risk of bias and provided limited evidence of the efficacy of psychotherapy. Adverse events were not reported in any of the included studies.
A psychological intervention, namely cognitive behavioural therapy, produced favourable effects on some psychological outcomes, in particular anxiety, depression and mood disturbance. However, the evidence for survival improvement is still lacking. These findings are open to criticism because of the notable heterogeneity across the included studies and the shortcomings of the included studies.