Outcome of Incidental T1a & b Prostate Cancer

1. No. 032 Outcome of Incidental T1a & b Prostate Cancer in the PSA era: Implications for Photo-Selective Vaporisation of the Prostate Simon V. Bariol, Ming-Chak Lee, Andrew Ling, Andrew Brooks, Malcolm Drummond, Howard Lau, Manish Patel, Audrey Wang, Henry Woo Department of Urology, Westmead Hospital, Western Sydney Local Health District, New South Wales, Australia Introduction Benign prostatic hypertrophy (BPH) affects a large number of middle aged and elderly men. The advent of Photo-Selective Vaporisation of the Prostate (PVP) has challenged the gold standard Transurethral Resection of the Prostate (TURP) procedure for treatment of BPH. However, despite advantages of reduced bleeding and hospital stay of PVP, there is the loss of prostate tissue examination, and therefore potential to miss an incidental prostate cancer diagnosis. Existing literature shows a decreasing incidence of prostate cancer diagnosed from TURPs, currently estimated at between 5.2-12.0%. This decline has been largely attributed to the increasing use of Prostate Specific Antigen (PSA) screening. Although a significant proportion of patients diagnosed with incidental prostate cancer are managed conservatively, a Japanese study by Masue et al found 56.5% of T1a patients and 86.5% of T1b patient underwent some form of treatment including either hormone therapy, radiotherapy, chemotherapy or surgery. The clinical outcome of these patients with incidentally diagnosed prostate cancer has not been well established. A recent Swedish register-based study found a 10-year prostate cancer-specific mortality of 23.3% in the PSA era for incidentally diagnosed prostate cancer compared with 35.1% among patients with non-incidental diagnosed prostate cancer. However, further studies examining the natural history of incidental T1a & b prostate cancer is necessary to determine the optimum management of these patients. Results Incidental prostate cancer was histopathologically confirmed in 31 (4.1%) of the 764 patients who underwent TURP procedures at Westmead hospital between 1999 and 2009. Of the 31 patients, 8 (25.8%) had stage T1a (less than 5% involvement), 18 (58.1%) had stage T1b (greater than 5% involvement) and in 5 (16.1%) cases, the percentage of cancer involvement was not recorded. In the 8 patients with T1a disease, only 1 (12.5%) subsequently underwent TRUS-guided biopsy due to the large size of the resected TURP specimen (weighing 63g). The biopsy result showed no malignancy and the patient was managed with watchful waiting. In the 18 patients with T1b disease, 11 (61.1%) were managed with watchful waiting without further investigation and 7 (38.9%) received TRUS-guided prostate biopsies. Of the 6 patients who had positive results, 4 underwent definitive therapy (Gleason scores of 9, 7, 6 & 5) and 2 were managed conservatively (Gleason scores of 6 & 6). The one remaining patient in the T1b group with a negative biopsy result was also managed with watchful waiting (Figure 2). All patients who received definitive management underwent prior TRUS-guided biopsies and there was no statistically significant difference between this group and those managed conservatively in terms of age, pre-op PSA, Gleason grade and volume of disease. There was no documented incidence of cancer progression in the patients with incidental prostate cancer. Furthermore, of the 3 (9.7%) patients in our series who died, none occurred as a consequence of prostate-specific disease. Aim To examine the management and outcomes of patients with incidental T1a & b prostate cancer diagnosed via TURP in a large Australian university hospital. Methods Medical records of all patients who had TURP procedures at Westmead hospital from 1999 to 2009 were analysed retrospectively to identify incidental cases of prostate cancer. Patients known to have prostate cancer prior to TURP were excluded. Information was collected regarding (1) histopathologically verified prostate cancer diagnosis, (2) subsequent treatment undertaken, (3) incidence of cancer progression, (4) any prostate cancer-specific morbidity +/- mortality. Conclusions Although a small proportion of prostate cancer diagnoses would be missed in patients undergoing PVP procedures, the majority are low grade. However, there remains a risk of missing a diagnosis of clinically significant prostate cancer diagnosis with PVP in the PSA era. Longer term follow-up is required to more accurately establish the natural history and clinical outcome of patients with incidental prostate cancer. References Jones, J.S; Follis, H.W and Johnson, J.R. Probability of finding T1a and T1b (Incidental) prostate cancer during TURP has decreased in the PSA era. Prostate cancer and prostatic diseases (2009) 12, 57-60. Masue, N; Deguchi, T; Nakano, M; Ehara, H; uno, H and Takahashi, Y. Retrospective study of 101 cases with incidental prostate cancer stages T1a and T1b. International Journal of Urology (2005) 12, 1045-1049. Acknowledgements Department of Urology, Westmead Hospital, NSW, Australia Poster presentation sponsor