The Evolution and Current Paradigm of Chemotherapy for Metastatic Castrate-Resistant Prostate Cancer

A comment on the International Society of Geriatric Oncology guidelines: evidence-based advice for the clinical setting

Largely a disease of older men, prostate cancer is likely to become a growing burden in the developed world as the population ages and overall life expectancy increases. Furthermore, prostate cancer management in older men is not optimal, reflecting the lack of training dedicated to senior adults in fellowship programs and the lack of specific guidelines to manage senior adults. The International Society of Geriatric Oncology (SIOG) convened a multidisciplinary Prostate Cancer Working Group to review the evidence base and provide advice on the management of the disease in senior age groups. The Working Group reported that advancing age, by itself, is not a reliable guide to treatment decision making for men with either localized or advanced prostate cancer. Instead, the SIOG guidelines advise health care teams to assess the patient's underlying health status, which is largely dictated by associated comorbid conditions, but also by dependency in activities of daily living and nutritional status, and to use the findings to categorize the individual into one of four groups: healthy, vulnerable, frail, or terminally ill. The guidelines recommend that a patient categorized as healthy or vulnerable (i.e., with reversible problems following geriatric intervention) should receive the same approach to treatment as a younger patient. Frail patients should be managed using adapted treatment strategies, and the terminally ill should receive symptomatic/palliative care only. The guidelines may have ongoing relevance as the treatment options for prostate cancer expand.

Management of prostate cancer

Prostate cancer is diagnosed in 37 000 new patients a year, and causes 10 000 deaths each year in the UK (Cancer Research UK, 2011). Diagnoses are increasingly the result of screening using measurement of prostate- specific antigen levels. The natural history of early disease is unclear. Autopsy studies before prostate-specific antigen screening showed an actual latent prevalence (not diagnosed during life) of around 30% at the age of 50 years and 75% at the age of 80 years, and many of these demonstrated local invasion (Franks, 1954). One of the main current challenges in urology is distinguishing indolent prostate cancers from potentially lethal ones. The specificity of the prostate-specific antigen test for clinically significant disease remains disappointingly low and population screening is not encouraged (Ilic et al, 2011). However, prostate-specific antigen testing is often done in good faith, but pre-test counselling is essential. Thus, prostate-specific antigen testing should only be undertaken by the patient's GP or on the advice of a urologist.