Contemporary practice of radiotherapy post radical prostatectomy at a tertiary referral centre in Australia

Introduction Adverse features on histopathology (pT3, PSM) for radical

prostatectomy (RP) holds increased risk for disease progression.

Radiotherapy (RT) given in the adjuvant fashion gives a 50-60% benefit for biochemical progression free survival (EORTC1, SWOG2).

Early salvage RT may give equivalent benefit with less overtreatment. Two major randomised controlled trials are looking into this (RAVES, RADICALS).

Conclusions At our centre, 70% of patients were treated in the salvage setting.

Within the limits of short follow-up, there is no significant difference in the demographics or outcomes of the two groups.

At a median of 19 months >94% of patients are biochemically recurrence free.

Results Median PSA was 7.6 pre surgery and median age at RRP 61 years.

At RRP 7% of patients were Gleason 7, 20% Gl8-9 and 3% Gl6.

Androgen Deprivation Therapy (ADT) ADT given with RT may help with biochemical recurrence and overall survival. In our

cohort 27 of 71 patients (38%) were given hormones at the time of RT; 8 in an adjuvant setting, 19 in salvage setting.

26 were given hormones at the time of RT. One was used for PSA relapse.

There was a trend towards those with more adverse features (pT3, PSM, PSA >0.2) being given ADT.

Biochemical Failure At median follow-up of 19 months, 4 patients had biochemical failure by the ASTRO

definition and 2 by the Phoenix definition.

1 patient was given adjuvant RT (no ADT); 3 were given salvage RT (all ADT)

2 patients had bony metastasis (both salvage RT with ADT)

Median time to failure was 19 months.

Methods A prospective RT database identified 112 patients given RT post RP

between June 2008 and July 2012.

Seventy-one patients had RP performed at the Austin and pathology results readily available.

Retrospective chart review looking at patient characteristics, histopathology results, PSA data, RT parameters and side effects were compiled into a database.

Results were analysed with the intention to give adjuvant or salvage RT irrespective of the timeframe in which they received treatment.

Aim The management of prostate cancer has huge geographical variation.

The results of International based trials may not apply to our population.

There is little in the way of published data in Australia on RT post RP.

The Austin is a tertiary referral centre for prostate cancer performing around 100 RPs per year.

Our aim was to report our local experience of adjuvant and early salvage RT post RP.

Overall Toxicity is low with only 1 case of RTOG GU Grade 3+ toxicity in the acute setting. There was no Grade 3+ late toxicity at time of analysis (Late only reported in 66 patients). There was no statistical difference between the adjuvant and salvage groups.

References1) M Bolla et al. Postoperative radiotherapy after radical prostatectomy for high-risk prostate cancer: long-term results of a randomised controlled trial (EORTC trial 22911) Lancet (2012) published online Oct 19

2) IM Thompson et al. Adjuvant radiotherapy for pathological T3N0M0 prostate cancer significantly reduces risk of metastases and improves survival: long-term followup of a randomized clinical trial. J Urol, 181 (2009), pp. 956–962

There was no significant difference in the number of patients with positive margins or extra-capsular extension between the adjuvant and salvage RT groups.

Comparison of patient characteristics in Adjuvant and Salvage RT groups.The median age at starting RT reflect the delay to treatment.

Kevin CHU 1, James JACKSON 2, Yvonne TAN 2, Daryl LIM-JOON 2, Damien BOLTON 1, Shomik SENGUPTA 1

1 Department of Urology, Austin Health, Melbourne, 2 Department of Radiation Oncology, Austin Health, Melbourne

No. 163

Posters Proudly Supported by:

Adjuvant Salvage

pT3 15/21(71%)

38/50(76%)

PSM 18/21(86%)

42/50(84%)

Grade Acute GU

Acute GI

Late GU

Late GI

1 37 (52%)

20 (28%)

10 (15%)

8 (12%)

2 10 (14%)

8 (11%)

1 (2%)

2 (3%)

3 1(1%)

0(0%)

0 (0%)

0 (0%)

Adjuvant Salvage

Number of Patients 21 (30%) 50 (70%)

Median Age at RT 62 64

Median time to RT 6 months 19 months

Average PSA UDT 0.47 (0.05-12)

Dose in Gy (typical) 66 70