The American Urological Association meeting this year was in San Antonio, Texas. This is the biggest urological meeting in the world with a very strong emphasis on prostate cancer update with respect to basic scientific research and clinical techniques and attitudes. The following is a brief summary of most current information presented at the AUA.

Age of diagnosis has continued to decrease in the PSA era. Ballentine Carter reported that younger men are more likely to have curable disease. PSA interpretation in younger men is less likely to be confounded by co-existent benign prostatic hyperplasia. The decrease in mortality of 4% per annum since 1994 was confirmed. The incidence rate however, is increasing at 2% per annum since 1995. This is independent of the effect of PSA screening. It is postulated that this increase may be due to lifestyle factors such as an increase in the average body mass index of the Western population. The Centre for Prostate Disease database found that by 1998 only 3.5% of men with carcinoma of the prostate presented with metastatic disease. They concluded that this is consistent with the screening program. For mortality to decrease as a result of screening the presentation of incurable disease must decline.

Aetiology refers to the causation of a disease. Work presented at the AUA confirmed that a first-degree relative has at least a three times increased incidence of contracting prostate cancer. The younger the age of the first-degree relative, the greater the risk to, for example, the son. A history of prostate cancer on the maternal side is also associated albeit more weakly with an increased risk of prostate cancer. The difference in racial susceptibility is thought to be due to differences in androgen metabolism, especially with respect to the activity of the five alpha reductase enzyme, which is responsible for converting testosterone to dihydrotestosterone. Three important unifying hypotheses were presented - the relationship between the oxidant and anti-oxidant balance, the intra-prostatic androgen balance as evidenced by the activity of five alpha reductase enzyme and the activity of IGF-1 levels. IGF represents insulin growth factor. Fascinating work based on the work of Dennis (Urol. 2002) demonstrated an eightfold increased risk for prostate cancer in men with a history of chronic prostatitis. This was based on a meta-analysis of the literature. It was postulated that infection increased the rate of free radical concentration within the prostate cancer cell and this combined with altered GST pi enzyme activity combined to create cellular mutation. It was postulated that anti-oxidants such as selenium may act to counter the increasing concentration of free radicals resulting from chronic prostatitis. The model of stomach cancer caused by a bacteria known as helico bacter pylori was compared. It was postulated that the three common anti oxidants taken to prevent prostate cancer, selenium, lycopene and vitamin E may act to interfere with this pathway towards cellular mutation. Once again, a diet high in animal fat was implicated with respect to causation. Also strongly implicated was obesity and a lack of physical exercise. It was postulated that obesity modifies the free radical concentration within the prostate. Obese men have doubled the risk of dying from prostate cancer and are more likely to be diagnosed with metastatic disease.

Large-scale prostate cancer prevention trials have been conducted and are currently underway. The Prostate Cancer Prevention Trial found that men taking Proscar (Finasteride) had a decreased likelihood of being diagnosed with prostate cancer at seven years, however, those who were diagnosed had an increased likelihood of having high-grade prostate cancer. This latter finding is the subject of considerable conjecture with many authorities suggesting that this observation is more artefactual than real. Nevertheless, the widespread use of Finasteride for chemo-prevention is not recommended. The SELECT trial suggests that a protective effect for daily vitamin E consumption. This was contrasted by other studies suggesting in fact a disadvantage and a third result suggesting no change at all in the likelihood of contracting prostate cancer. The use of statins which are cholesterol lowering drugs was observed to be linked to a lower risk of advanced prostate cancer. The men taking Statins had a third the risk of metastatic disease or death. The much-applauded work of Leitzmann (Jama 2004) concluded that "high ejaculation frequency was related to decreased risk of prostate cancer". Leitzmann defined high ejaculation as 21 ejaculations per month.

Twelve biopsies are now recommended as a routine rather than sextant biopsies. The biopsies should be taken from a lateral prostatic position. The number of positive cores, tumour length and percentage involvement was predictive of the pathological stage, (Singh H J, Urol. 2004). The significance of high-grade prostatic intra epithelium neoplasia was extensively studied. One study concluded that only 4.5% of men would be found to have prostate cancer on repeat biopsy after the initial biopsy demonstrated the presence of high grade PIN. Atypical small acinar proliferation (ASAP) was associated with a 36% chance of positive biopsy on re-biopsy of the prostate (More C K J, Ural 2005). Bastian P J (Cancer 2001) reported that "insignificant prostate cancer as defined as Gleason score less than six and less than three positive cores with less than 50% affected had associated with it an 8.4% chance of non organ confined disease. He concluded that the majority of T1C disease had significant disease.

The work of Antenor in a longitudinal screening study demonstrated that an initial PSA was strongly associated with subsequent prostate cancer development. For example, an initial PSA between 2-3 had a relative risk of prostate cancer of 14.9 in the Antenor study whereas it was associated with a relative risk of 5.5 in the Gann study. PSA velocity, an increase in PSA over time was presented as being by far the most dependable of all the PSA parameters. The annual increase of .75 nanograms per ml per year was presented as being acceptable. Work was presented demonstrating that a PSA increase of greater than 2 nanograms per ml two years before diagnosis was associated with a poor prognosis regardless of treatment. Whereas, a PSA velocity of less than .5 nanograms per ml per year in a man diagnosed with prostate cancer may indicate a patient suitable for active surveillance rather than active intervention. Thompson (NEJN 2004) demonstrated that at seven years 15% of men with a PSA less than 4 would have prostate cancer and that 15% of those diagnosed would have Gleason 7 prostate cancer. The PSA doubling time following surgical or radiotherapeutic treatment was highly significant with respect to prognosis. A PSA doubling time of less than three months was associated with a poor five-year survival. It was felt that the PSA doubling time post treatment could be used to identify those at risk of rapid progression. These men could be offered multi-modality therapy including the new chemotherapy protocols in a trial setting.

The technique of robot assisted laproscopic radical prostatectomy was much discussed at the AUA. It was agreed that meticulous surgical technique was the most critical determinant of a good surgical outcome, not the technology used to perform the operation. It was concluded that "the robot does not make a bad surgeon into a good operator". Conversely, it was accepted that many good surgeons prefer to use the robot to perform radical prostatectomy. In conclusion, the three goals of cure, preservation of potency and preservation of continence are more important than the manner in which the operation is performed.

The development of the fields of Genomics with its gene micro array technology and proteomics utilising mass spectroscopy are attempting to find new prostate cancer specific bio-markers. The use of magnetic resonance imaging and spectroscopy continues to generate interest both for guiding prostate biopsies and for predicting biologically significant prostate cancer. Emerging therapies include the use of Docetaxel, a chemotherapeutic agent which has been shown to prolong life by two to three months for patients with hormone resistant prostate cancer. Prostate cancer vaccines such as the dendritic cell vaccine continue to attract research interest.

Prostate cancer continues world wide to attract significant research funding in all aspects from screening to managing hormone resistant disease. Prevention is better than cure. Men should focus on a high fibre low fat diet supplemented by regular exercise.