Radiation therapy after radical prostatectomy: A single-centre radiation oncology experience in trends of referral and treatment practices

Patterns of Care Related to Post-Operative Radiotherapy for Patients with Prostate Cancer among Canadian Radiation Oncologists and Urologists

The American Society for Radiation Oncology (ASTRO) and American Urological Association (AUA) developed post-prostatectomy radiotherapy (RT) guidelines to aid patient counseling on adjuvant (ART) and salvage radiotherapy (SRT). Our study compared how aware and compliant Canadian radiation oncologists and urologists are to these guidelines. Our online survey was distributed through the Canadian Association of Radiation Oncology (CARO) and Canadian Urology Association (CUA) to radiation oncologists and urologists that treat prostate cancer. We used Wilcoxon rank-sum test and Chi-square test to compare radiation oncologists and urologists. P values for significant findings are reported. A total of 128 participants responded the survey, 52 radiation oncologists, and 76 urologists. The majority (82%) of radiation oncologists had read these guidelines, compared to only 49% of urologists (p < 0.001). Radiation oncologists were more likely to recommend ART >50% for adverse pathological findings post-radical prostatectomy compared to urologists (76 vs. 51%, p = 0.011). Urologists were more likely to monitor their patient's PSA level post-prostatectomy compared to radiation oncologists (93 vs. 77%, p = 0.016). Post-thematic analysis of open-ended questions revealed that urologists rarely refer patients to radiation oncologists for ART, with radiation oncologists confirming that they rarely receive referrals. This study demonstrates the low compliance to ASTRO/AUA guidelines. While radiation oncologists were more aware and compliant to guidelines, urologists were significantly more likely to monitor their patient's PSA. This study highlighted the need for better communication between urologists and radiation oncologists, especially in referrals for ART, to facilitate treatment delivery that is concordant with ASTRO/AUA guidelines.

Assessing guideline impact on referral patterns of post-prostatectomy patients to radiation oncologists

INTRODUCTION

Adjuvant radiotherapy (aRT) can improve biochemical progression-free survival in patients with high-risk features (HRF) after radical prostatectomy (RP). Guidelines from Alberta and the Genitourinary Radiation Oncologists of Canada (GUROC) recommend that patients with HRF be referred to radiation oncologists (RO) based on the findings from three randomized, controlled trials (RCT). Our study examines the impact of these recommendations both pre- (2005) and post- (2012) publication of RCT and GUROC guideline establishment.

METHODS

Patients undergoing RP during 2005 and 2012 were identified from the provincial cancer registry. Charts were retrospectively reviewed and variables of interest were linked to the registry data. RO referral patterns for each year were determined and variables influencing referral (extracapsular extension, positive margin, seminal vesicle invasion, and post-RP prostate-specific antigen [PSA]) were compared.

RESULTS

Median time to referral was 26.4 months in 2005 compared to 3.7 months 2012 (p<0.001). Among patients referred post-RP, a higher proportion was referred within six months in 2012 (21%) as compared to 2005 (13%) (p=0.003). Among eligible patients in 2012, 30% were referred for discussion of aRT compared to 24% in 2005 (p=0.003). There was a marked drop in patients referred for salvage radiation therapy beyond six months and a rise in the number of patients who are never referred.

CONCLUSIONS

Despite an increase in referral rates to RO post-RP from 2005-2012, more than 50% of those patients with HRF did not receive a referral. Initiatives aimed at improving multidisciplinary care and guideline adherence should be undertaken.