Prostate cancer: the new evidence base for diagnosis and treatment.

Although prostate cancer (PC) has a significant mortality, there is debate regarding the utility of PC screening. This debate continues as major studies investigating the value of population-based screening have yet to be concluded. Despite this, there is increasing evidence from preliminary reports from these series, as well as numerous others relating to outcome prediction for PC, that early detection leads to improved outcomes and a decrease in the burden of metastatic disease on our healthcare system. PC is rarely symptomatic until it has metastasised to bone and because of this PSA-based screening remains the only widely available and reliable method of diagnosis for organ-confined disease. There is now compelling evidence to show that: 1. Cancers diagnosed by screening are more likely to be early stage, when most can be cured by a number of different treatment options. 2. The maximum benefits of screening are for men aged 50-70 years. Older men have a greater chance of a clinically insignificant cancer being diagnosed for which treatment is not necessary. 3. The familial risks of PC are well recognised. In particular, men with one or more first-degree relatives already diagnosed with the disease should be actively encouraged to undergo screening. 4. Modern histopathological assessment of fine core needle biopsies of the prostate allows for the likely behaviour of cancer present to be accurately predicted. Changes that mimic those of malignancy can be confidently identified, so these cases are no longer incorrectly diagnosed. These improvements mean that now most men aged 50-70 years diagnosed with PC will have clinically significant cancers that require treatment.

PSA testing and DRE, TRUS scanning with sector biopsy, improved histology, curative treatments, and active surveillance for prostate cancer: a success story for men's health.

PSA, DRE, and TRUS sector biopsy have been used clinically internationally for almost two decades and have been available in New Zealand since 1993. The incidence of prostate cancer has approximately doubled. Many countries especially in Western Europe, North America and including Australia report decreases in prostate cancer mortality due to this change ranging from 10 to 39%. This has not so far occurred in New Zealand, however, and likely reasons for this are discussed. They include a negative approach encouraged by the New Zealand Guidelines Group and others, and more difficult access to investigations and treatments for New Zealand men than other countries. Technological advances in TRUS sector biopsy, histological diagnosis, and management are discussed. Changes in international prostate cancer mortality data and results from several clinical trials are also discussed. It is concluded that the weight of evidence in favour of PSA/DRE testing is now overwhelming and that potentially between 200 and 300 of the 600 men who currently die of prostate cancer in New Zealand could be saved by the application of current technology.