Analysis of pathologic extent of disease for clinically localized prostate cancer after radical prostatectomy and subsequent use of adjuvant radiation in a national cohort

The impact of positive surgical margin parameters and pathological stage on biochemical recurrence after radical prostatectomy: A systematic review and meta-analysis

BACKGROUND

To systematically review and perform a meta-analysis on the predictive value of the primary Gleason grade (PGG) at the positive surgical margin (PSM), length of PSM, number of PSMs, and pathological stage of the primary tumor on biochemical recurrence (BCR) in patients with prostate cancer (PCa) after radical prostatectomy (RP).

METHODS

A systematic literature search was performed using electronic databases, including PubMed, EMBASE, Cochrane Library, and Web of Science, from January 1, 2005, to October 1, 2023. The protocol was pre-registered in PROSPERO. Subgroup analyses were performed according to the different treatments and study outcomes. Pooled hazard ratios with 95% confidence intervals were extracted from multivariate analyses, and a fixed or random effect model was used to pool the estimates. Subgroup analyses were performed to explore the reasons for the heterogeneity.

RESULTS

Thirty-one studies that included 50,028 patients with PCa were eligible for this meta-analysis. The results showed that, compared to PGG3, PGG4/5 was associated with a significantly increased risk of BCR. Compared with PSM ≤3 mm, PSM ≥3 mm was associated with a significantly increased risk of BCR. Compared with unifocal PSM, multifocal PSM (mF-PSM) was associated with a significantly increased risk of BCR. In addition, pT >2 was associated with a significantly increased risk of BCR compared to pT2. Notably, the findings were found to be reliable based on the sensitivity and subgroup analyses.

CONCLUSIONS

PGG at the PSM, length of PSM, number of PSMs, and pathological stage of the primary tumor in patients with PCa were found to be associated with a significantly increased risk of BCR. Thus, patients with these factors should be treated differently in terms of receiving adjunct treatment and more frequent monitoring. Large-scale, well-designed prospective studies with longer follow-up periods are needed to validate the efficacy of these risk factors and their effects on patient responses to adjuvant and salvage therapies and other oncological outcomes.

Prognostic Value of Gleason Score at Positive Surgical Margin in Prostate Cancer: A Systematic Review and Meta-analysis

The individual clinical significance of a positive surgical margin (PSM) after radical prostatectomy has remained controversial. Studies have suggested that the Gleason grade (GG) at the PSM could improve predictive accuracy and decision making. Our objective was to systematically review the reported data to determine the effect of the GG at the PSM on the prognosis after radical prostatectomy. A systematic review was conducted by searching MEDLINE/PubMed for studies reported by June 2019 in accordance with the Preferred Reporting Items for Systematic Review statement. The keywords used included prostate cancer, radical prostatectomy, positive surgical margin, Gleason score, and/or Gleason grade. After a systematic literature review, 10 studies were included, comprising 14,108 patients, of whom 2454 (17.4%) had a PSM and 428 (14%) eventually experienced biochemical recurrence (BCR) within a median follow-up of 18 to 156 months. Data on neoadjuvant or adjuvant therapy were not estimable. In a meta-analysis, GG4 at PSM was significantly associated with BCR compared with GG3 (pooled hazard ratio, 1.87; 95% confidence interval, 1.53-2.28; z = 6.16). The Cochrane Q test (χ² = 5.88; P = .318) and I² test (I² = 15.0%) showed that no significant heterogeneity was present. GG4 at a PSM is a feature of biologically and clinically aggressive prostate cancer that is associated with a significant increase risk of BCR. GG at PSM should be recorded in each pathological report. Given this adverse prognostic value patients with GG4 at the PSM should be considered for multimodal therapy such as radiotherapy.

Urologists' referral and radiation oncologists' treatment patterns regarding high-risk prostate cancer patients receiving radiotherapy within 6 months after radical prostatectomy: A prospective cohort analysis

INTRODUCTION

Previous studies have observed low rates of adjuvant radiotherapy after radical prostatectomy (RP) for high-risk prostate cancer patients. However, it is not clear the extent to which these low rates are driven by urologists' referral and radiation oncologists' treatment patterns.

METHOD

The Clinician-Led Improvement in Cancer Care (CLICC) implementation trial was conducted in nine public hospitals in New South Wales, Australia. Men who underwent RP for prostate cancer during 2013-2015 and had at least one high-risk pathological feature of extracapsular extension, seminal vesicle invasion and/or positive surgical margins were included in these analyses. Outcomes were as follows: (i) referral to a radiation oncologist within 4 months after RP ('referred'); (ii) commencement of radiotherapy within 6 months after RP among those who consulted a radiation oncologist ('radiotherapy after consultation').

RESULTS

Three hundred and twenty-five (30%) of 1071 patients were 'referred', and 74 (61%) of 121 patients received 'radiotherapy after consultation'. Overall, the probability of receiving radiotherapy within 6 months after RP was 15%. The probability of being 'referred' increased according to higher 5-year risk of cancer-recurrence (P < 0.001).

CONCLUSION

Only 30% of patients with high-risk features are referred to a radiation oncologist with the likelihood of referral being influenced by the perceived risk of cancer-recurrence as well as the urologist's institutional/personal preference. When patients are seen by a radiation oncologist, 61% receive radiotherapy within 6 months after RP with the likelihood of receiving radiotherapy not being heavily influenced by increasing risk of recurrence. This suggests many suitable patients would receive radiotherapy if referred and seen by a radiation oncologist.

Travel Distance as a Barrier to Receipt of Adjuvant Radiation Therapy After Radical Prostatectomy

OBJECTIVES

Following radical prostatectomy (RP), adjuvant radiation therapy (RT) decreases biochemical recurrence and potentially improves metastasis-free and overall survival for patients with high-risk pathologic features. Since adjuvant RT typically occurs daily over several weeks, the logistical challenges of extensive traveling may be a significant barrier to its use. We examined the association between distance to treatment facility and use of adjuvant RT.

MATERIALS AND METHODS

We identified 97,568 patients in the National Cancer Database diagnosed from 2004 through 2011 with cT1-4N0-xM0-x prostate cancer and found to have high-risk pathologic features (pT3-4 stage and/or positive surgical margins) at RP. Multivariable logistic regression adjusting for sociodemographic and clinicopathologic factors was used to examine the association between travel distance and receipt of adjuvant RT, defined as radiotherapy initiated within 12 months after RP.

RESULTS

Overall, 10.6% (10,346) of the study cohort received adjuvant RT. On multivariable analysis, increasing travel distance was significantly associated with decreased use of adjuvant RT, with adjusted odds ratios of 1.0 (reference), 0.67, 0.46, 0.39, and 0.32 (all P<0.001) and prevalence of use at 12.6%, 8.8%, 6.3%, 4.9%, and 3.7% for patients living ≤25.0, 25.1 to 50.0, 50.1 to 75.0, 75.1 to 100.0, and >100.0 miles away, respectively.

CONCLUSIONS

Increasing travel distance was strongly associated with decreased use of adjuvant RT in this national cohort of postprostatectomy patients with high-risk pathologic features. These results strongly suggest that the logistical challenges of extensive travel are a significant barrier to the use of adjuvant RT. Efforts aimed at improving access to radiotherapy and reducing treatment time are urgently needed.

Pre- and post-prostatectomy variables associated with pelvic post-operative radiotherapy in prostate cancer patients: a national registry-based study

BACKGROUND

In patients with prostate cancer (PCa), the lack of clear guidelines on the use of radiotherapy after radical prostatectomy (RP) invites unwanted variation of this treatment. We describe the hazard ratios and probabilities related to the use of post-RP radiotherapy.

MATERIAL AND METHODS

Data were collected from the Cancer Registry of Norway and nine radiotherapy units. All patients were diagnosed with a non-metastatic PCa from January 2004 through June 2011. Adjuvant radiotherapy was defined as pelvic radiotherapy initiated <5 months after RP at a PSA <0.2 ng/ml. All other pelvic radiotherapy series were categorized as salvage radiotherapy, and, combined with adjuvant radiotherapy they were termed post-RP radiotherapy.

RESULTS

Of 6840 prostatectomized patients, 1170 (17%) had undergone post-RP radiotherapy, mainly as salvage radiotherapy. The number of adjuvant radiotherapy series almost tripled from 2009. Based on pre-prostatectomy variables (PSA, Gleason score, and clinical risk group) and findings in the prostatectomy specimens (status of resection margins, pathological tumor category and Gleason's score), the probability of post-RP radiotherapy ranged respectively from 14% to 73%, and from 4% to 83%.

CONCLUSIONS

In our study, post-RP radiotherapy was applied in approximately one in six patients. Based on the combination of PCa-specific variables routinely available at the time of diagnosis, a patient's probability of post-RP radiotherapy can be determined before decision of primary treatment strategy, followed by probability determination based on histopathological variables emerging from the prostatectomy specimen.

Patterns of care of IMRT usage in postoperative management of uterine cancer

OBJECTIVE

To analyze the patterns of care regarding intensity modulated radiation therapy (IMRT) usage in the postoperative management of uterine cancer.

METHODS

The National Cancer Database was queried to identify women with endometrial adenocarcinoma who underwent hysterectomy followed by external beam radiation between 2004-2012. Descriptive statistics were used to analyze IMRT usage with comparison via the Chi Square test. Overall survival was also compared between IMRT and three dimensional conformal radiation therapy. Multivariable logistic regression and multivariable Cox Regression were used to identify covariables that impact IMRT usage and improved survival respectively.

RESULTS

7839 women were included in this study. IMRT utilization increased from 1.9% in 2004 to 32.4% in 2012 (p<0.001). The adjusted odds ratio (OR) for IMRT in 2012 compared with 2004 was 24.90, 95% CI 15.24-40.67 (p<0.001). Aside from year, other predictors of IMRT usage on multivariate analysis were positive nodes, higher dose, private insurance and higher income. Black race was associated with lower IMRT usage compared to Whites with an OR of 0.60, 95% CI 0.44-0.81 (p=0.001). IMRT was not associated with significantly increased survival (HR 0.86, 95% CI 0.73-1.01, p=0.06). Black race and positive nodes were associated with decreased survival within the group studied whereas private insurance and higher income were associated with improved survival.

CONCLUSIONS

In this hospital-based registry, IMRT has significantly increased in utilization for postoperative radiation in uterine cancer between 2004-2012 although not resulting in significantly improved survival. Socioeconomic and racial disparities exist in the allocation of IMRT usage.

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.

The impact of body mass index on treatment outcomes for patients with low-intermediate risk prostate cancer

Background

Little is known about the relationship between preoperative body mass index and need for adjuvant radiation therapy (RT) following radical prostatectomy. The goal of this study was to evaluate the utility of body mass index in predicting adverse clinical outcomes which require adjuvant RT among men with organ-confined prostate cancer (PCa).

Methods

We used a prospective cohort of 1,170 low-intermediate PCa risk men who underwent radical prostatectomy and evaluated the effect of body mass index on adverse pathologic features and freedom from biochemical failure (FFbF). Clinical and pathologic variables were compared across the body mass index groups using an analysis of variance model for continuous variables or χ² for categorical variables. Factors related to adverse pathologic features were examined using logistic regression models. Time to biochemical recurrence was compared across the groups using a log-rank survivorship analysis. Multivariable analysis predicting biochemical recurrence was conducted with a Cox proportional hazards model.

Results

Patients with elevated body mass index (defined as body mass index ≥25 kg/m²) had greater extraprostatic extension (p = 0.004), and positive surgical margins (p = 0.01). Elevated body mass index did not correlate with preoperative risk groupings (p = 0.94). However, when compared with non-obese patients (body mass index <30 kg/m²), obese patients (body mass index ≥30 kg/m²) were much more likely to have higher rate of adverse pathologic features (p = 0.006). In patients with low- and intermediate- risk disease, obesity was strongly associated with rate of pathologic upgrading of tumors (p = 0.01 and p = 0.02), respectively. After controlling for known preoperative risk factors, body mass index was independently associated with ≥2 adverse pathologic features (p = 0.002), an indicator for adjuvant RT as well as FFbF (p = 0.001).

Conclusions

Body mass index of ≥30 kg/m² is independently associated with adverse pathologic features, which is an indicator for additional RT, particularly in patients with low-intermediate risk disease. Future studies may determine if this select group of patients may be best treated with definitive RT to reduce toxicity from additional RT following radical prostatectomy. We propose including body mass index in clinical decision-making for appropriate treatment recommendation for patients with low-intermediate risk PCa.

Patterns of Postprostatectomy Adjuvant Radiotherapy Techniques for Nonmetastatic Prostate Cancer in a Large National Cohort

PURPOSE

To analyze the contemporary patterns of care regarding adjuvant radiotherapy (RT) techniques for patients with pT3/4 disease or positive margins after prostatectomy.

PATIENTS AND METHODS

Men who were diagnosed with nonmetastatic prostate cancer and underwent prostatectomy between 2004 and 2012 were abstracted from the National Cancer Data Base. Only those with pT3-4Nx-0M0 or pT2cNx-0M0 with positive margins were included. We identified patients receiving RT to the pelvis to a dose between 5940 and 7560 cGy. Delivery of hormone therapy was also identified. Descriptive statistics were used to determine adjuvant RT use as well as patterns of care regarding RT dose and hormone use; data were compared by Pearson's chi-square test.

RESULTS

A total of 133,874 men were included in this study, of whom 12,073 (9.0%) received adjuvant RT. Of those receiving adjuvant RT, 4011 (33.2%) also received hormone therapy. There was a trend toward more frequent use of higher RT doses over time. RT doses of ≥ 7000 cGy were provided 21.4% of the time in 2004-2006 and increased over time to 38.9% by 2010-2012 (P < .001). There was also a rapid increase in the use of intensity-modulated radiotherapy from 20.7% of patients in 2004 to 69.2% in 2012.

CONCLUSION

Most men (91.0%) with pT3/T4 or pT2 disease with positive margins do not receive adjuvant RT. Use of intensity-modulated radiotherapy and RT dose escalation increased over time and are now used routinely. Hormone therapy is used in about one third of patients who are receiving RT, and its use has remained relatively stable over time.

Gaps between Evidence and Practice in Postoperative Radiotherapy for Prostate Cancer: Focus on Toxicities and the Effects on Health-Related Quality of Life

Adjuvant radiotherapy (ART) after prostatectomy for patients with high-risk features [extracapsular extension (ECE), seminal vesicle invasion (SVI), and positive margin] has been shown to be associated with improved biochemical disease-free survival in three large randomized trials and with improved overall survival in one. Similarly, salvage radiotherapy (SRT) can effectively achieve biochemical control in a significant proportion of patients with a rising PSA after surgery. Nonetheless, both approaches of postoperative RT remain highly underutilized. This might be partly due to concerns with overtreatment inherent to adjuvant approaches, and/or hesitance about causing radiation toxicities and their subsequent effects on the patient's quality of life. Herein, we review the literature lending evidence to these arguments. We show recent series of ART/SRT and their low rates of acute and long-term toxicities, translating only in transient decline in quality-of-life (QoL) outcomes. We conclude that concerns with side effects should not preclude the recommendation of an effective and curative-intent therapy for men with prostate cancer initially treated with radical surgery.

Predictors and rate of adjuvant radiation therapy following radical prostatectomy: A report from the Prostate Cancer Registry

INTRODUCTION

Long-term data from three randomized trials have demonstrated that adjuvant radiation therapy (ART) reduces the rate of biochemical failure in high-risk men following radical prostatectomy (RP). One of these trials has shown a survival advantage. We investigated the rate of ART in Victoria and the predictors for this treatment.

METHODS

We analysed data from eligible patients who were notified to the Victorian Prostate Cancer Registry (PCR) by 37 Victorian hospitals between 1 August 2008 and 31 October 2011. We defined ART as radiation therapy (RT) delivered within 6 months of RP. Predictors of ART receipt were modelled using adjusted and unadjusted logistic regression.

RESULTS

There were 4626 eligible cases from which 2018 underwent RP with recorded date of surgery. Of these eligible prostatectomy cases, a total of 89 received ART. A subgroup of 833 men had an adverse pathologic feature, of whom 78 received ART. In a multivariate model, pathologic tumour stage pT3a (odds ratio (OR) 2.64; 95% confidence interval (CI) 1.4-5.00; P = 0.003), pT3b (OR 4.58; 95% CI 2.12-9.89; P = 0.000), a positive surgical margin (OR 8.91; 95% CI 4.61-17.2; P = 0.000) and pathologic Gleason grade >7 (OR 7.18; 95% CI 1.54-33.6; P = 0.012) predicted receipt of ART.

CONCLUSION

Adverse pathologic features and high pathologic Gleason score predict for receiving ART in Victorian men after RP, but overall, ART is not commonly prescribed. This finding is consistent with other published series and may reflect clinician scepticism regarding the benefit of ART over salvage RT and concern about toxicity and the risk of over treatment.

A population-based analysis of contemporary patterns of care in younger men (<60 years old) with localized prostate cancer

PURPOSE

To analyze patterns of care in younger patients (<60 years old) with localized prostate cancer and to identify factors associated with selection of therapy using a large, population-based database.

METHODS

The Surveillance, Epidemiology, and End Results database was queried to identify men <60 years old diagnosed with localized prostate cancer between 2010 and 2011. Patients were determined to have undergone no active treatment, local therapy, radiation therapy (RT), or radical prostatectomy (RP). Univariate and multivariate logistic regression analyses were performed to identify factors associated with the use of definitive therapy.

RESULTS

A total of 12,732 men were included in this analysis. For the entire cohort, 12.5 % received no definitive treatment, 61.6 % RP, 22.0 % RT, and 3.3 % RP with adjuvant RT. Among men with low-, intermediate-, and high-risk prostate cancer, 17.2, 7.1, and 15.9 %, respectively, received no definitive therapy. RP was the most common choice of definitive therapy, utilized in 74.6 % of patients. Adjuvant RT after RP was utilized in 16.2 % of cases with positive margin and/or pT3/pT4 disease. African-American race, single marital status, and Medicaid/no insurance were associated with a decreased likelihood of receiving definitive treatment.

CONCLUSIONS

A significant proportion of younger men diagnosed with localized prostate cancer, particularly with low- or high-risk disease, are not receiving definitive therapy. African-American men, uninsured men, and patients with Medicaid or no medical insurance are less likely to receive definitive treatment.

Artificial urinary sphincter erosion after radical prostatectomy in patients treated with and without radiation

INTRODUCTION

There has been increasing evidence supporting the use of adjuvant radiotherapy after radical prostatectomy (RP) for prostate cancer. Significant stress incontinence after RP is not uncommon and the artificial urinary sphincter (AUS) is the gold standard of treatment. Our objective was to assess if increased use of radiotherapy after RP has changed the rate of erosion and infection in the face of improvement in radiation technique and equipment in men who had an AUS implanted in the last 10 years.

METHODS

We retrospectively examined 118 patients from December 2001 to January 2012 who underwent a RP with or without postoperative radiotherapy and subsequently had an AUS implanted. We divided the patients into two cohorts (Group 1: December 2001-December 2006 and Group 2: January 2007-January 2012). We reviewed all patient records for age, cuff size implanted, history of postoperative radiotherapy, previous incontinence surgery, revisions, and complications (erosion/infection).

RESULTS

There were 36 and 82 patients in Groups 1 and 2, respectively. The mean age was similar between groups, 67 years both groups (p = 0.980). The number of patients treated with postoperative radiotherapy was similar between groups (36% vs. 32%, p = 0.640, respectively). There was no difference in the incidence of erosion or infection between Group 1 and 2 (p = 0.848 and p = 0.178, respectively). The overall relative risk (RR) of erosion was significantly higher in those who had radiotherapy compared to those who did not (RR 4.05, 95% confidence interval 1.1-15.3).

CONCLUSIONS

Over the last 10 years, there has not been an increase in the number of patients receiving an AUS after RP and radiotherapy at our centre. During this time, the incidence of erosion and infection has not increased. However, our study reaffirms that the relative risk of erosion remains higher in patients who have had radiotherapy despite improvement in radiation treatment techniques and equipment.

Adjuvant versus salvage radiation therapy for prostate cancer patients with adverse pathologic features: comparative analysis of long-term outcomes

OBJECTIVES

To compare long-term outcomes of men with adverse pathologic features after adjuvant radiation therapy (ART) versus salvage radiation therapy (SRT) after radical prostatectomy at our institution.

METHODS

Patients treated with postprostatectomy radiation therapy with pT3 tumors, or pT2 with positive surgical margins, were identified. Cumulative freedom from biochemical failure (FFBF), freedom from metastatic failure (FFMF), and overall survival rates were estimated utilizing the Kaplan-Meier method. Multivariate analyses were performed to determine independent prognostic factors correlated with study endpoints. Propensity score analyses were performed to adjust for confounding because of nonrandom treatment allocation.

RESULTS

A total of 186 patients with adverse pathologic features treated with ART or SRT were identified. The median follow-up time after radical prostatectomy was 103 and 88 months after completion of radiation therapy. The Kaplan-Meier estimates for 10-year FFBF was 73% and 41% after ART and SRT, respectively (log-rank, P=0.0001). Ten-year FFMF was higher for patients who received ART versus SRT (98.6% vs. 80.9%, P=0.0028). On multivariate analyses there was no significant difference with respect to treatment group in terms of FFBF, FFMF, and overall survival after adjusting for propensity score.

CONCLUSIONS

Although unadjusted analyses showed improved FFBF with ART, the propensity score-adjusted analyses demonstrated that long-term outcomes of patients treated with ART and SRT do not differ significantly. These results, with decreased effect size of ART after adjusting for propensity score, demonstrate the potential impact of confounding on observational research.

Genomic classifier identifies men with adverse pathology after radical prostatectomy who benefit from adjuvant radiation therapy

PURPOSE

The optimal timing of postoperative radiotherapy (RT) after radical prostatectomy (RP) is unclear. We hypothesized that a genomic classifier (GC) would provide prognostic and predictive insight into the development of clinical metastases in men receiving post-RP RT and inform decision making.

PATIENTS AND METHODS

GC scores were calculated from 188 patients with pT3 or margin-positive prostate cancer, who received post-RP RT at Thomas Jefferson University and Mayo Clinic between 1990 and 2009. The primary end point was clinical metastasis. Prognostic accuracy of the models was tested using the concordance index for censored data and decision curve analysis. Cox regression analysis tested the relationship between GC and metastasis.

RESULTS

The cumulative incidence of metastasis at 5 years after RT was 0%, 9%, and 29% for low, average, and high GC scores, respectively (P = .002). In multivariable analysis, GC and pre-RP prostate-specific antigen were independent predictors of metastasis (both P < .01). Within the low GC score (< 0.4), there were no differences in the cumulative incidence of metastasis comparing patients who received adjuvant or salvage RT (P = .79). However, for patients with higher GC scores (≥ 0.4), cumulative incidence of metastasis at 5 years was 6% for patients treated with adjuvant RT compared with 23% for patients treated with salvage RT (P < .01).

CONCLUSION

In patients treated with post-RP RT, GC is prognostic for the development of clinical metastasis beyond routine clinical and pathologic features. Although preliminary, patients with low GC scores are best treated with salvage RT, whereas those with high GC scores benefit from adjuvant therapy. These findings provide the first rational selection of timing for post-RP RT.

Radiation therapy after radical prostatectomy for prostate cancer: evaluation of complications and influence of radiation timing on outcomes in a large, population-based cohort

Purpose

To evaluate the influence of timing of salvage and adjuvant radiation therapy on outcomes after prostatectomy for prostate cancer.

Methods

Using the Surveillance, Epidemiology, and End Results-Medicare linked database, we identified prostate cancer patients diagnosed during 1995–2007 who had one or more adverse pathological features after prostatectomy. The final cohort of 6,137 eligible patients included men who received prostatectomy alone (n = 4,509) or with adjuvant (n = 894) or salvage (n = 734) radiation therapy. Primary outcomes were genitourinary, gastrointestinal, and erectile dysfunction events and survival after treatment(s).

Results

Radiation therapy after prostatectomy was associated with higher rates of gastrointestinal and genitourinary events, but not erectile dysfunction. In adjusted models, earlier treatment with adjuvant radiation therapy was not associated with increased rates of genitourinary or erectile dysfunction events compared to delayed salvage radiation therapy. Early adjuvant radiation therapy was associated with lower rates of gastrointestinal events that salvage radiation therapy, with hazard ratios of 0.80 (95% CI, 0.67–0.95) for procedure-defined and 0.70 (95% CI, 0.59, 0.83) for diagnosis-defined events. There was no significant difference between ART and non-ART groups (SRT or RP alone) for overall survival (HR = 1.13 95% CI = (0.96, 1.34) p = 0.148).

Conclusions

Radiation therapy after prostatectomy is associated with increased rates of gastrointestinal and genitourinary events. However, earlier radiation therapy is not associated with higher rates of gastrointestinal, genitourinary or sexual events. These findings oppose the conventional belief that delaying radiation therapy reduces the risk of radiation-related complications.

Low rates of adjuvant radiation in patients with nonmetastatic prostate cancer with high-risk pathologic features

BACKGROUND

The 2013 American Urological Association/American Society for Radiation Oncology consensus guidelines recommend offering adjuvant radiotherapy (RT) after radical prostatectomy in patients with high-risk pathologic features for recurrence. In the current study, the authors examined practice patterns of adjuvant RT use in patients with elevated pathologic risk factors over a time period spanning the publication of supporting randomized evidence.

METHODS

Using the National Cancer Data Base, a total of 130,681 patients were identified who underwent surgical resection for prostate cancer between 2004 and 2011 with at least 1 of the following pathologic risk factors for early biochemical failure: pT3a disease or higher, positive surgical margins and/or lymph node-positive disease. Using multivariable logistic regression, the authors examined factors associated with adjuvant RT use including patient, clinical, demographic, and temporal characteristics.

RESULTS

Adjuvant RT was administered to 9.9% of the patients with at least 1 pathologic risk factor. Use of adjuvant RT did not change over the study period (P  = .23). On multivariable analysis, we found that patients treated at high-volume surgical facilities were less likely to receive adjuvant RT (15.9% vs 7.8%; odds ratio, 0.58 [95% confidence interval, 0.50-0.65]; P < .0001). Older age, comorbidities, black race, lower income, and lower population density were also associated with lower rates of adjuvant RT.

CONCLUSIONS

Use of adjuvant RT is uncommon and remained unchanged between 2004 and 2011. Patients treated at high-volume surgical facilities are less likely to receive adjuvant RT, irrespective of margin status.

Prediction of extraprostatic extension in patients with clinically organ-confined prostate cancer

INTRODUCTION

Preoperative parameters for predicting extraprostatic extension (ECE) in clinically organ-confined prostate cancer patients are not well defined. Our aim was to evaluate the roles of the biopsy Gleason score, prostate-specific antigen (PSA)-based parameters, volume, and clinical T classification in prediction of ECE.

MATERIALS AND METHODS

A total of 188 patients with clinically organ-confined prostate cancer who underwent radical prostatectomy from January 1998 to December 2007 were included in the study. Age, prostate volume, preoperative total serum PSA (tPSA), free PSA, PSA density (PSAD), biopsy Gleason score, and clinical T classification were analyzed by univariate and multivariate analyses to predict ECE.

RESULTS

Pathologic examination revealed 130 patients had organ-confined disease and 58 patients were positive for ECE. Multivariate logistic regression analyses showed that tPSA was an independent predictor of ECE. Gleason score ≥8 had a trend for predicting ECE. Receiver operating characteristic (ROC) curves suggested that tPSA and PSAD had a similar diagnosis performance in the whole cohort. For patients with Gleason score of 7, PSAD was found to be statistically better than tPSA for predicting ECE.

CONCLUSIONS

tPSA remains one of the most important factors for predicting ECE in prostate cancer patients. PSAD may be more helpful than tPSA for predicting ECE in the patients with Gleason score of 7.

The need for, and utilization of prostate-bed radiotherapy after radical prostatectomy for patients with prostate cancer in British Columbia

INTRODUCTION

Three randomized trials have demonstrated that post-radical prostatectomy (RP) radiotherapy decreases biochemical relapse for those with adverse pathology. Our purpose was to describe the incidence of pathologic risk factors for recurrence in a contemporary series of patients treated with RP and to describe the use of post-RP radiotherapy.

METHODS

All incident prostate cancers diagnosed between January 2005 and December 2007 were identified from the tumour registry. Cases were then linked to radiotherapy records which included dose and modality (external beam radiotherapy and brachytherapy). The pathology reports in the tumour registry were reviewed for pathologic stage, grade and margin status.

RESULTS

We identified 9223 patients with prostate cancer. Overall, 36.3% of patients treated with RP had positive margins, and may have benefited from adjuvant radiotherapy. After RP, 332 (15%) patients had radiotherapy to the prostate bed; of these, only 25 (1.1%) received truly adjuvant radiotherapy (delivered within 6 months with a prostate-specific antigen of <0.2 ng/mL). Of the 2181 patients treated with RP, 270 (12%) were seen by a radiation oncologist within 6 months of RP. Of the 1015 patients (47%) with adverse RP pathology (positive margins, extracapsular extension or seminal vesicle invasion), 230 (23%) were seen by a radiation oncologist within 6 months of RP.

CONCLUSION

Not all patients with adverse prostatectomy pathology were seen by a radiation oncologist post-prostatectomy, and very few received adjuvant radiotherapy despite almost half of them having risk factors for relapse.

Comparative effectiveness research for prostate cancer radiation therapy: current status and future directions

Comparative effectiveness research aims to help clinicians, patients and policymakers make informed treatment decisions under real-world conditions. Prostate cancer patients have multiple treatment options, including active surveillance, androgen deprivation therapy, surgery and multiple modalities of radiation therapy. Technological innovations in radiation therapy for prostate cancer have been rapidly adopted into clinical practice despite relatively limited evidence for effectiveness showing the benefit for one modality over another. Comparative effectiveness research has become an essential component of prostate cancer research to help define the benefits, risks and effectiveness of the different radiation therapy modalities currently in use for prostate cancer treatment.

Costs of early adjuvant radiation therapy after radical prostatectomy: a decision analysis

BACKGROUND

This analysis was carried out to evaluate the cost-effectiveness of adjuvant radiation therapy (ART) versus observation, using a decision analysis model based primarily upon the published results of the Southwest Oncology Group prospective trial (SWOG 8794).

PATIENTS AND METHODS

A decision analysis model was designed to compare ART versus observation over a 10-year time horizon. Probabilities of treatment success, utilization of salvage treatments, and rates of adverse events were taken from published results of SWOG 8794. Cost inputs were based on 2010 Medicare reimbursement rates. Primary outcome measure was incremental cost per prostate-specific antigen (PSA) success (i.e. serum PSA level <0.4 ng/ml).

RESULTS

ART results in a higher PSA success rate than observation with probability of 0.43 versus 0.22. The mean incremental cost per patient for ART versus observation was $6023. The mean incremental cost-effectiveness ratio was $26,983 over the 10-year period.

CONCLUSIONS

ART appears cost effective compared with observation based upon this decision analysis model. Future research should consider more costly radiation therapy (RT) approaches, such as intensity-modulated RT, and should evaluate the cost-effectiveness of ART versus early salvage RT.

Postprostatectomy radiation therapy: an evidence-based review

While the majority of men with localized prostate cancer who undergo a radical prostatectomy will remain disease free, men with certain clinical and pathological features are known to be at an increased risk for developing a biochemical recurrence and, ultimately, distant metastatic disease. The optimal management of these patients continues to be a source of controversy. To date, three randomized Phase III trials have demonstrated that adjuvant radiation therapy (ART) for patients with certain adverse pathological features results in an improvement in several clinically-relevant end points, including biochemical recurrence-free survival and overall survival. Despite the evidence from these trials showing a benefit for ART, many believe that ART results in overtreatment and unwarranted treatment morbidity for a significant number of patients. Many physicians, therefore, instead advocate for close observation followed by early salvage radiation therapy (SRT) at the time of a biochemical recurrence. The purpose of this review is to evaluate the evidence for and to distinguish between ART and early SRT. We will also highlight current and future areas of research for this patient population, including radiation treatment dose escalation, hypofractionation and androgen deprivation therapy. We will also discuss the cost–effectiveness of ART and early SRT.

Physician beliefs and practices for adjuvant and salvage radiation therapy after prostatectomy

PURPOSE

Despite results of randomized trials that support adjuvant radiation therapy (RT) after radical prostatectomy (RP) for prostate cancer with adverse pathologic features (APF), many clinicians favor selective use of salvage RT. This survey was conducted to evaluate the beliefs and practices of radiation oncologists (RO) and urologists (U) regarding RT after RP.

METHODS AND MATERIALS

We designed a Web-based survey of post-RP RT beliefs and policies. Survey invitations were e-mailed to a list of 926 RO and 591 U. APF were defined as extracapsular extension, seminal vesicle invasion, or positive surgical margin. Differences between U and RO in adjuvant RT recommendations were evaluated by comparative statistics. Multivariate analyses were performed to evaluate factors predictive of adjuvant RT recommendation.

RESULTS

Analyzable surveys were completed by 218 RO and 92 U (overallresponse rate, 20%). Adjuvant RT was recommended based on APF by 68% of respondents (78% RO, 44% U, p <0.001). U were less likely than RO to agree that adjuvant RT improves survival and/or biochemical control (p < 0.0001). PSA thresholds for salvage RT were higher among U than RO (p < 0.001). Predicted rates of erectile dysfunction due to RT were higher among U than RO (p <0.001). On multivariate analysis, respondent specialty was the only predictor of adjuvant RT recommendations.

CONCLUSIONS

U are less likely than RO to recommend adjuvant RT. Future research efforts should focus on defining the toxicities of post-RP RT and on identifying the subgroups of patients who will benefit from adjuvant vs. selective salvage RT.

Extended sampling at first biopsy improves cancer detection rate: results of a prospective, randomized trial comparing 12 versus 18-core prostate biopsy

PURPOSE

We determined whether increasing the number of cores at first prostate biopsy would improve the cancer detection rate without increasing the detection of clinically insignificant tumors.

MATERIALS AND METHODS

From January 2009 to January 2010 patients scheduled for prostate biopsy were randomized to 12 or 18-core sampling. Study inclusion criteria were 1) age 45 to 75 years, 2) abnormal digital rectal examination and/or prostate specific antigen 4 to 20 ng/ml, and 3) no previous biopsy. The primary end point was the cancer detection rate. Secondary end points were clinically insignificant cancer detection and morbidity.

RESULTS

A total of 150 patients were enrolled in the study. Preoperative variables were similar in the 2 groups of 75 patients each. Cancer was detected in 23 patients (30.7%) in group 1 and in 36 (48%) in group 2 (p = 0.02). More cases of insignificant cancer were detected in group 2 (p not significant). In men with prostate volume 65 cc or less the detection rate was 30.9% in group 1 and 52.8% in group 2 (p = 0.02). In men with prostate specific antigen 10 ng/ml or less the detection rate was 19.6% in group 1 and 38.4% in group 2 (p = 0.03). Two group 2 patients (5.5%) were diagnosed based on additional samples but the diagnosis corresponded to insignificant cancer. There was no statistically significant difference in morbidity.

CONCLUSIONS

The 18-core protocol improves prostate cancer detection without increasing morbidity. Results suggest that the 12-core biopsy protocol is adequate for prostate cancer detection at first biopsy.