Shared decision-making in prostate cancer care

Abstract

Most men with low-risk prostate cancer have several treatment options. Since there is no clear evidence that one option is better than another in terms of overall survival, the decision-making process is mainly guided by patients’ values and preferences . Therefore, patients with prostate cancer are increasingly engaged in the process of treatment decision-making. The purpose of this thesis was to: (1) describe factors that influence the treatment decision-making process (Chapter 2-3); and (2) explore how treatment decisions influence patients’ health-related quality of life after treatment (Chapter 4-6). In Chapter 2, we describe that the majority of patients with low-risk prostate cancer poorly understood the differences in disease recurrence, overall survival and risks of side effects among the various treatment options. More than half of the patients inaccurately perceived surgery as being more effective than radiotherapy in terms of risk of disease recurrence. Most patients underestimated the risks of side-effects following surgery compared to radiotherapy. And most patients overestimated the likelihood of eventually needing to start definitive treatment after a period of active surveillance. These misperceptions were less common in patients who consulted a radiotherapist or a clinical nurse specialist, and more common in men with elevated levels of emotional distress. In Chapter 3 we report that patients with localized prostate cancer who were actively involved in treatment decision-making had more knowledge about prostate cancer, experienced less decisional conflict, and less regret than patients who reported having experienced passive involvement. Additionally, patients who experienced less involvement than preferred experienced higher levels of decisional conflict. Therefore, our findings support a policy of encouraging all localized prostate cancer patients to be actively involved in the decision about their treatment. In Chapter 4 we describe differences in patient-reported physical and psychological functioning after treatment. Twelve months after treatment, surgery was associated with urinary incontinence, sexual dysfunction, and declined feelings of masculinity; external beam radiotherapy was associated with sexual dysfunction, hormonal/masculinity-related symptoms, and physical distress; and brachytherapy was associated with more urinary obstruction and irritative urinary symptoms, when compared to patients who started active surveillance. Decisional regret was comparable among treatment options. However, men who experienced hormonal/masculinity-related symptoms, who had less formal education and/or men with positive surgical margins reported more regret about the treatment decision. This information can be used to inform future patients about the benefits and risks of each treatment option. After surgery some patients experience biochemical recurrence (a PSA level that is not below 0). These patients are offered additional radiotherapy (salvage radiotherapy). The optimal timing to start this treatment is unknown. We observed that a longer interval (i.e. more time) between surgery and salvage radiotherapy was associated with significantly better sexual and urinary function (Chapter 5). Many men with prostate cancer will become long-term survivors (alive ≥ 5 years post-diagnosis). In Chapter 6 we evaluated differences in the prevalence of mental health problems between prostate cancer survivors and age-matched men from the general population. Long-term prostate cancer survivors had poorer mental health than men of a comparable age from the general population without a history of prostate cancer.