Australian patterns of prostate cancer care: Are they evolving?

Disease mapping: Geographic differences in population rates of interventional treatment for prostate cancer in Australia

BACKGROUND

Treatment decisions for men diagnosed with prostate cancer depend on a range of clinical and patient characteristics such as disease stage, age, general health, risk of side effects and access. Associations between treatment patterns and area-level factors such as remoteness and socioeconomic disadvantage have been observed in many countries.

OBJECTIVE

To model spatial differences in interventional treatment rates for prostate cancer at high spatial resolution to inform policy and decision-making.

METHODS

Hospital separations data for interventional treatments for prostate cancer (radical prostatectomy, low dose rate and high dose rate brachytherapy) for men aged 40 years and over were modelled using spatial models, generalised linear mixed models, maximised excess events tests and k-means statistical clustering.

RESULTS

Geographic differences in population rates of interventional treatments were found (p<0.001). Separation rates for radical prostatectomy were lower in remote areas (12.2 per 10 000 person-years compared with 15.0-15.9 in regional and major city areas). Rates for all treatments decreased with increasing socioeconomic disadvantage (radical prostatectomy 19.1 /10 000 person-years in the most advantaged areas compared with 12.9 in the most disadvantaged areas). Three groups of similar areas were identified: those with higher rates of radical prostatectomy, those with higher rates of low dose brachytherapy, and those with low interventional treatment rates but higher rates of excess deaths. The most disadvantaged areas and remote areas tended to be in the latter group.

CONCLUSIONS

The geographic differences in treatment rates may partly reflect differences in patients' physical and financial access to treatments. Treatment rates also depend on diagnosis rates and thus reflect variation in investigation rates for prostate cancer and presentation of disease. Spatial variation in interventional treatments may aid identification of areas of under-treatment or over-treatment.

Variation in radiotherapy patterns of care in the radical treatment of South Australian men with non-metastatic prostate cancer between 2005-2015

BACKGROUND AND PURPOSE

To investigate associations between socio-demographic characteristics and radiotherapy patterns of care in non-metastatic prostate cancer [nmPCa] in South Australia [SA] between 2005-2015 and document practice patterns over time.

MATERIALS AND METHODS

Men with nmPCa receiving primary curative radiotherapy were identified from SA Prostate Cancer Clinical Outcomes Collaborative database. Adjuvant, salvage and palliative therapies were excluded. Associations between socio-demographic factors (age, residence, socio-economic status, diagnostic period) and radiotherapy mode (external beam radiotherapy [EBRT] vs. brachytherapy [BT]) and technique (low-dose-rate vs. high-dose-rate brachytherapy) were investigated using multivariable logistic regression with separate models for clinical risk categories.

RESULTS

Of the 1874 men who underwent primary RT, 80% received EBRT and 20% BT. For low and intermediate risk disease, likelihood of receiving EBRT was higher among older men (OR_low = 3.08; 95% CI 1.82-5.22 and OR_intermediate = 3.48; 2.28-5.31 for 65-74 yrs vs. <65 yrs) and lower among regional/remote compared with metropolitan residents (OR_low = 0.34; 0.17-0.67 and OR_intermediate = 0.57; 0.34-0.94). For intermediate and high risk disease, more recent diagnosis was associated with decreased likelihood of EBRT (OR_intermediate = 0.22; 95% CI 0.15-0.33 and OR_high = 0.50; 0.29-0.88, respectively). Among men receiving BT, low-dose-rate BT use decreased over time for low (OR = 0.19; 0.04-0.89) and intermediate risk disease (OR = 0.32; 0.12-0.84). Dose escalation and intensity modulation for EBRT increased after 2010.

CONCLUSION

Over the last decade substantial changes in RT for nmPCa were observed. Older age and more remote residence may be barriers to accessing specific types of RT. Further research to understand how these factors affect access is warranted to improve service provision.

Patterns of care and outcomes for men diagnosed with prostate cancer in Victoria: an update

BACKGROUND

To update patterns of care for men diagnosed with prostate cancer in Victoria, Australia between 2008 and 2015.

METHODS

From August 2008 to December 2015, 14 025 men diagnosed with prostate cancer were included. These data were obtained from the Prostate Cancer Outcome Registry - Victoria (PCOR-Vic). Frequencies were used to describe hospital and patient characteristics and treatment types. Comparisons were made between previous period of analysis (2008-2011) to the most recent period (2011-2015). Survival analysis using a stepwise Cox proportional hazards regression model was performed.

RESULTS

Mean age of diagnosis was 66.5 years and 44% of patients were diagnosed with Gleason 7 prostate cancer. Majority of notifications (63.6%) were received from a private institution and 70.2% of patients were diagnosed at a metropolitan institution. Most patients (95.3%) were diagnosed with clinically localized disease. Within 12 months of diagnosis, 55.9% of patients with low-risk disease received no active treatment. Radical prostatectomy was the most common primary treatment with curative intent (47%). When comparing of patterns of care between 2008-2011 and 2011-2015, the proportion of patients diagnosed with Gleason 9-10 disease increased, as has the proportion of patients diagnosed with metastatic disease.

CONCLUSION

With the PCOR-Vic, we were able to identify that increasing number of patients were diagnosed with high-risk and metastatic disease. There has been an overall decrease in radical treatment rates, likely due to active surveillance playing a significant role especially in patients with low-risk prostate cancer.

The Cambridge Prognostic Groups for improved prediction of disease mortality at diagnosis in primary non-metastatic prostate cancer: a validation study

BACKGROUND

The purpose of this study is to validate a new five-tiered prognostic classification system to better discriminate cancer-specific mortality in men diagnosed with primary non-metastatic prostate cancer.

METHODS

We applied a recently described five-strata model, the Cambridge Prognostic Groups (CPGs 1-5), in two international cohorts and tested prognostic performance against the current standard three-strata classification of low-, intermediate- or high-risk disease. Diagnostic clinico-pathological data for men obtained from the Prostate Cancer data Base Sweden (PCBaSe) and the Singapore Health Study were used. The main outcome measure was prostate cancer mortality (PCM) stratified by age group and treatment modality.

RESULTS

The PCBaSe cohort included 72,337 men, of whom 7162 died of prostate cancer. The CPG model successfully classified men with different risks of PCM with competing risk regression confirming significant intergroup distinction (p < 0.0001). The CPGs were significantly better at stratified prediction of PCM compared to the current three-tiered system (concordance index (C-index) 0.81 vs. 0.77, p < 0.0001). This superiority was maintained for every age group division (p < 0.0001). Also in the ethnically different Singapore cohort of 2550 men with 142 prostate cancer deaths, the CPG model outperformed the three strata categories (C-index 0.79 vs. 0.76, p < 0.0001). The model also retained superior prognostic discrimination in the treatment sub-groups: radical prostatectomy (n = 20,586), C-index 0.77 vs. 074; radiotherapy (n = 11,872), C-index 0.73 vs. 0.69; and conservative management (n = 14,950), C-index 0.74 vs. 0.73. The CPG groups that sub-divided the old intermediate-risk (CPG2 vs. CPG3) and high-risk categories (CPG4 vs. CPG5) significantly discriminated PCM outcomes after radical therapy or conservative management (p < 0.0001).

CONCLUSIONS

This validation study of nearly 75,000 men confirms that the CPG five-tiered prognostic model has superior discrimination compared to the three-tiered model in predicting prostate cancer death across different age and treatment groups. Crucially, it identifies distinct sub-groups of men within the old intermediate-risk and high-risk criteria who have very different prognostic outcomes. We therefore propose adoption of the CPG model as a simple-to-use but more accurate prognostic stratification tool to help guide management for men with newly diagnosed prostate cancer.

Evaluation of the changing landscape of prostate cancer diagnosis and management from 2005 to 2016

Background

Approaches to prostate cancer (PCa) diagnosis and treatment have evolved significantly over past decades. There has been an increasing focus on minimizing overdiagnosis and overtreatment of clinically insignificant PCa. The objective of this study was to evaluate the changes in the diagnostic approach and initial treatment strategy that has evolved over time in an Australian urological private practice.

Materials and methods

Men with newly diagnosed PCa were identified from the private practice electronic and paper medical records from 2005 to 2016 and data was consolidated into six groups of 2-year intervals. Diagnostic strategy was analyzed with particular reference to the use of multiparametric magnetic resonance imaging (mpMRI) scan and ⁶⁸Ga-prostate specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) scans. National Comprehensive Cancer Network risk group stratification was correlated with initial treatment strategy and compared over time.

Results

Chart review identified 839 men who had a mean age of 65.8 years. In 2011–2012, prebiopsy mpMRI scan was introduced. Its uptake correlated with a decrease in numbers of men diagnosed with low risk cancer (r = -0.80, P = 0.04) and an increase in numbers of men diagnosed with high-risk cancer (r = 0.90, P = 0.01). The use of ⁶⁸Ga-PSMA PET/CT was associated with decreasing use of CT and bone scans performed. Open radical prostatectomy had a declining trend particularly when robotic surgery (robotic assisted radical prostatectomy (RARP)) was introduced. Pelvic lymph node dissections performed progressively decreased. An increased use of luteinizing hormone receptor hormone (LHRH) antagonists was seen in favor of LHRH agonists. Whilst use of high dose rate brachytherapy declined, there was an increased use of low dose rate brachytherapy.

Conclusion

Prebiopsy mpMRI has been associated with an increased proportion of newly diagnosed men having clinically significant PCa. Over time, ⁶⁸Ga-PSMA PET/CT scans, robotic assisted radical prostatectomy (RARP) and LHRH antagonists have increased in use, whilst CT and bone scans, and pelvic lymph node dissections have decreased.

The Effect of Evolving Strategies in the Surgical Management of Organ-Confined Prostate Cancer: Comparison of Data from 2005 to 2014 in a Multicenter Setting

Introduction

The objective of this study was to evaluate changes of patient characteristics and surgical techniques in radical prostatectomy in Germany within the last decade.

Methods

Data from 44 German prostate cancer centers were included in the study. Patients’ characteristics (age, initial PSA value), surgical techniques (open vs. minimally invasive approaches), perioperative parameters (operating time, rate of nerve-sparing (NS) radical prostatectomies (RPs), hospitalization time, catheter indwelling time, surgical margin status, number of dissected lymph nodes (LN)), and pathological findings (tumor stage, Gleason score) were analyzed.

Results

Data from 11,675 patients who underwent RP between 2005 and 2014 were analyzed. The rate of open RP approaches decreased by 1.7% (p = 0.0164), the rate of minimally invasive approaches increased by 1.8% (p = 0.0164). Robot-assisted RPs (RARP) increased by 4.6% (p < 0.0001). The number of NS procedures and pelvic lymphadenectomy (LA) increased by 4.5% (p < 0.0001) and 4.7% (p < 0.0001), respectively. Catheter indwelling time and hospitalization time decreased by 1 day (p < 0.0001). No change in the rate of positive surgical margins (p = 0.5061) and the ratio of positive lymph nodes removed (p = 0.4628) was observed. The number of Gleason ≤6 tumors decreased significantly (p < 0.0001).

Conclusions

The number of RARP has significantly increased over the past decade and there is a trend towards surgeries on more advanced tumors with higher yields of lymph nodes dissected. At the same time, the rate of nerve-sparing procedures has significantly increased.

Prostate cancer screening with prostate-specific antigen: A guide to the guidelines

Background

Prostate cancer remains the most common non-skin cancer malignancy in men. Prostate-specific antigen (PSA) is recognized as a biomarker for the diagnosis, monitoring, and risk prediction of prostate cancer. Its use in the setting of prostate cancer screening has been controversial due to the risk of over diagnosis and over treatment.

Objective

Within Australia, there are inconsistent recommendations surrounding the use of PSA screening in clinical practice. In light of the 2016 PSA-screening guidelines by the major Australian health authorities, the current review aims to highlight the controversies and objectively outline the current recommendations within Australia.

Discussion

Health-care authorities across Australia have issued conflicting guidelines for prostate cancer screening culminating in confusion amongst health care practitioners and members of the public alike. A general consensus is held by other countries across the globe but differences amongst the specific details in how to best employ a PSA screening program still exist.