Predictive factors for late genitourinary and gastrointestinal toxicity in patients with prostate cancer treated with adjuvant or salvage radiotherapy

Late genitourinary toxicity in salvage radiotherapy for prostate cancer after radical prostatectomy: impact of daily fraction doses

OBJECTIVE

To evaluate the impact of daily fraction doses on late genitourinary (GU) toxicity after salvage radiotherapy (SRT) for prostate cancer.

METHODS

This multi-institutional retrospective study included 212 patients who underwent SRT between 2008 and 2018. All patients received image-guided intensity-modulated SRT at a median dose of 67.2 Gy in 1.8-2.3 Gy/fraction. The cumulative rates of late grade ≥2 GU and gastrointestinal (GI) toxicities were compared using Gray test, stratified by the ≤2.0 Gy/fraction (n = 137) and ≥2.1 Gy/fraction groups (n = 75), followed by multivariate analyses. The total dose was represented as an equivalent dose in 2-Gy fractions (EQD2) with α/β = 3 Gy.

RESULTS

After a median follow-up of 63 months, the cumulative rates of 5-year late grade ≥2 GU and GI toxicities were 14% and 2.5%, respectively. The cumulative rates of 5-year late grade ≥2 GU toxicity in the ≥2.1 Gy/fraction and ≤2.0 Gy/fraction groups were 22% and 10%, respectively (P = .020). In the multivariate analysis, ≥2.1 Gy/fraction was still associated with an increased risk of late grade ≥2 GU toxicity (hazard ratio, 2.37; 95% confidence interval, 1.12-4.99; P = .023), while the total dose was not significant.

CONCLUSION

The present results showed that ≥2.1 Gy/fraction resulted in a higher incidence of late grade ≥2 GU toxicity in SRT.

ADVANCES IN KNOWLEDGE

The impact of fraction doses on late GU toxicity after SRT remains unknown. The results suggest that higher fraction doses may increase the risk of late GU toxicity in SRT.

Why Do Men Reject Adjuvant Radiotherapy following Radical Prostatectomy? A Systematic Survey

INTRODUCTION

The aim of this study was to investigate non-adherence rates to adjuvant radiotherapy (aRT) after radical prostatectomy (RP) and to obtain patient reported reasons for rejecting aRT despite recommendation by a multidisciplinary team discussion (MTD).

METHODS

In a retrospective monocentric analysis, we identified 1,197 prostate cancer patients who underwent RP between 2014 and 2022 at our institution, of which 735 received a postoperative MTD recommendation. Patients with a recommendation for aRT underwent a structured phone interview with predefined standardised qualitative and quantitative questions and were stratified into "adherent" (aRT performed) and "non-adherent" groups (aRT not performed).

RESULTS

Of 55 patients receiving a recommendation for aRT (7.5% of all RP patients), 24 (44%) were non-adherent. Baseline tumour characteristics were comparable among the groups. "Fear of radiation damage" was the most common reason for rejection, followed by "lack of information," "feeling that the treating physician does not support the recommendation" and "the impression that aRT is not associated with improved oncological outcome." Salvage radiotherapy was performed in 25% of non-adherent patients.

CONCLUSION

High rates of non-adherence to aRT after RP were observed, and reasons for this phenomenon are most likely multifactorial. Multidisciplinary and individualized patient counselling might be a key for increasing adherence rates.

Impact of radiation doses on clinical relapse of biochemically recurrent prostate cancer after prostatectomy

The relationship between radiation doses and clinical relapse in patients receiving salvage radiotherapy (SRT) for biochemical recurrence (BCR) after radical prostatectomy (RP) remains unclear. We identified 292 eligible patients treated with SRT between 2005 and 2018 at 15 institutions. Clinical relapse-free survival (cRFS) between the ≥ 66 Gy (n = 226) and < 66 Gy groups (n = 66) were compared using the Log-rank test, followed by univariate and multivariate analyses and a subgroup analysis. After a median follow-up of 73 months, 6-year biochemical relapse-free survival, cRFS, cancer-specific survival, and overall survival rates were 58, 92, 98, and 94%, respectively. Six-year cRFS rates in the ≥ 66 Gy and < 66 Gy groups were 94 and 87%, respectively (p = 0.022). The multivariate analysis revealed that Gleason score ≥ 8, seminal vesicle involvement, PSA at BCR after RP ≥ 0.5 ng/ml, and a dose < 66 Gy correlated with clinical relapse (p = 0.015, 0.012, 0.024, and 0.0018, respectively). The subgroup analysis showed the consistent benefit of a dose ≥ 66 Gy in patients across most subgroups. Doses ≥ 66 Gy were found to significantly, albeit borderline, increase the risk of late grade ≥ 2 GU toxicity compared to doses < 66 Gy (14% vs. 3.2%, p = 0.055). This large multi-institutional retrospective study demonstrated that a higher SRT dose (≥ 66 Gy) resulted in superior cRFS.

Comparison Between Dose-Escalated Intensity Modulated Radiation Therapy and 3-Dimensional Conformal Radiation Therapy for Salvage Radiation Therapy After Prostatectomy

Purpose

To compare long-term outcomes and late toxicity between patients treated with 3-dimensional conformal radiation therapy (3D-CRT) and with dose-escalated intensity modulated radiation therapy (IMRT) as salvage radiation therapy (SRT) after prostatectomy.

Methods and Materials

A total of 110 patients who had been treated at our institution between 2010 and 2018 with SRT for biochemical recurrence after radical prostatectomy were included. The patients were treated either by 3D-CRT with 64 Gy (59 patients) or by IMRT with 70 Gy (51 patients). The irradiation target was the prostate bed only (106 patients) or the prostate bed and pelvic region (4 patients). Twelve patients (11%) received concurrent androgen deprivation therapy. The differences in clinical outcomes and late gastrointestinal (GI) and genitourinary (GU) toxicity between the 3D-CRT and IMRT groups were retrospectively assessed. Toxicities were recorded using the Common Terminology Criteria for Adverse Events, version 5.0. Prostate-specific antigen (PSA) progression after SRT was defined as an increase in the serum PSA level of 0.2 ng/mL from the PSA nadir after SRT and confirmed by a second PSA measurement that was higher than the first.

Results

The median follow-up time was 7.8 years for 3D-CRT (range:,0.3-9.2 years) and 3.1 years for IMRT (range, 0.4-7.2 years). There was no significant difference in the 4-year biochemical no-evidence-of-disease (bNED) rate between the 3D-CRT and IMRT groups (43.5% vs 52.1%; P = .20). Toxicity analysis showed no significant difference in late GI or GU toxicities of grade 2 or greater between the 3D-CRT and IMRT groups. The respective 4-year cumulative rates of toxicity in the 3D-CRT and IMRT groups were as follows: grade ≥2 GI toxicity, 8.8% and 4.4% (P = .42); grade ≥2 GU toxicity, 19.1% and 20.3% (P = .93); and grade ≥2 hematuria, 5.3% and 8.0% (P = .67). In the 3D-CRT group, the 8-year cumulative rates of GI toxicity, GU toxicity, and hematuria of grade 2 or greater were 8.8%, 28.4%, and 12.6%, respectively.

Conclusions

Dose-escalated IMRT showed no improvements in bNED or late toxicity compared with 3D-CRT. In addition, the results suggest that GU toxicity can occur after a long period (even after 6 years), whereas GI toxicity is seldom newly observed after 4 years.

Outcomes and Prediction Models for Exclusive Prostate Bed Salvage Radiotherapy among Patients with Biochemical Recurrence after Radical Prostatectomy

BACKGROUND

The addition of androgen-deprivation therapy (ADT) or pelvic radiation to prostate bed salvage radiotherapy (SRT) has been debated for prostate cancer patients with biochemical recurrence (BCR) after radical prostatectomy. This study aimed to assess the outcomes and propose prediction models for exclusive prostate bed SRT.

METHODS

This is a prospective observational cohort study with patients who underwent SRT with a pre-SRT PSA < 1.5 ng/mL after radical prostatectomy. Patients were treated with 70-Gy SRT to the prostate bed exclusively. Kaplan-Meier survival analyses and Cox regression analyses were applied for depicting and predicting BCR-free survival, ADT-free survival, and metastasis-free survival (MFS). Regression-based coefficients were used to develop nomograms.

RESULTS

A total of 105 patients were included and 91 patients were eligible. The median follow-up period was 39 months. The 5-year BCR-free survival, ADT-free survival, and MFS were 37%, 50%, and 66%, respectively. Multivariable analysis showed that a pre-SRT PSA < 0.45 ng/mL was the only independent factor associated with longer BCR-free survival (p = 0.034), while a PSA-DT > 8 months had better ADT-free survival (p = 0.008). Patients with a PSA-DT > 8 months showed a 100% MFS and a 43% 5-year absolute benefit in MFS than a PSA-DT ≤ 8 months. All patients with a pre-SRT PSA < 0.45 ng/mL and PSA-DT > 8 months were free from subsequent ADT and any metastasis.

CONCLUSIONS

In patients with a PSA < 0.45 ng/mL and PSA-DT > 8 months for post-prostatectomy BCR, prostate bed SRT provided excellent outcomes without the need for concomitant ADT or pelvic radiotherapy.

A comparison of side-effects and quality-of-life in patients operated on for prostate cancer with and without salvage radiation therapy

PURPOSE

The extent of late side-effects in prostate cancer patients, after radical prostatectomy (RP = reference group) and salvage radiation therapy (SRT) in a self-reporting perspective (PROM) is still under-reported. We aimed to investigate the rate and severity of side-effects and quality-of-life (QoL) according to PROM.

METHODS AND MATERIALS

A PROM survey was administered to a cohort of SRT patients matched to a reference group with median follow-up 10 years after surgery. In total, 740 patients were analyzed. To investigate the association between SRT versus reference group regarding side-effects and QoL, a Poisson regression analysis was conducted and presented as relative risk estimates (RR) together with 95% confidence intervals regarding questions related to urinary, rectal, sexual symptoms and QoL.

RESULTS

RRs ranged from of 1.7-6.5 on rectal symptoms and 1.2-1.4 for urinary symptoms. In general health, QoL and sexual function all RRs were below 1.1. With increasing age, higher RRs were seen for urinary leakage and lowered sexual function whereas longer time following irradiation showed higher RRs for rectal symptoms and rectal leakage. Limitations of this study include the cross-sectional design and lack of baseline assessment.

CONCLUSIONS

Adding SRT to RP does not seem to result in other than acceptable side-effects in the majority of men receiving SRT when taking a long follow-up time (median 10 years after surgery) into account. However, a subset of men develop severe side-effects where rectal bleeding dominates.

Impact of advanced radiotherapy techniques and dose intensification on toxicity of salvage radiotherapy after radical prostatectomy

The safety and efficacy of dose-escalated radiotherapy with intensity-modulated radiotherapy (IMRT) and image-guided radiotherapy (IGRT) remain unclear in salvage radiotherapy (SRT) after radical prostatectomy. We examined the impact of these advanced radiotherapy techniques and dose intensification on the toxicity of SRT. This multi-institutional retrospective study included 421 patients who underwent SRT at the median dose of 66 Gy in 2-Gy fractions. IMRT and IGRT were used for 225 (53%) and 321 (76%) patients, respectively. At the median follow-up of 50 months, the cumulative incidence of late grade 2 or higher gastrointestinal (GI) and genitourinary (GU) toxicities was 4.8% and 24%, respectively. Multivariate analysis revealed that the non-use of either IMRT or IGRT, or both (hazard ratio [HR] 3.1, 95% confidence interval [CI] 1.8-5.4, p < 0.001) and use of whole-pelvic radiotherapy (HR 7.6, CI 1.0-56, p = 0.048) were associated with late GI toxicity, whereas a higher dose ≥68 Gy was the only factor associated with GU toxicities (HR 3.1, CI 1.3-7.4, p = 0.012). This study suggested that the incidence of GI toxicities can be reduced by IMRT and IGRT in SRT, whereas dose intensification may increase GU toxicity even with these advanced techniques.

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.

Proton therapy- the modality of choice for future radiation therapy management of Prostate Cancer?

BACKGROUND

Proton Therapy (PR) is an emerging treatment for prostate cancer (Pca) patients. However, limited and conflicting data exists regarding its ability to result in fewer bladder and rectal toxicities compared to Photon Therapy (PT), as well as its cost efficiency and plan robustness.

MATERIALS AND METHODS

An electronic literature search was performed to acquire eligible studies published between 2007 and 2018. Studies comparing bladder and rectal dosimetry or Gastrointestinal (GI) and Genitourinary (GU) toxicities between PR and PT, the plan robustness of PR relative to motion and its cost efficiency for Pca patients were assessed.

RESULTS

28 studies were eligible for inclusion in this review. PR resulted in improved bladder and rectal dosimetry but did not manifest as improved GI/GU toxicities clinically compared to PT. PR plans were considered robust when specific corrections, techniques, positioning or immobilisation devices were applied. PR is not cost effective for intermediate risk Pca patients; however PR may be cost effective for younger or high risk Pca patients.

CONCLUSION

PR offers improved bladder and rectal dosimetry compared to PT but this does not specifically translate to improved GI/GU toxicities clinically. The robustness of PR plans is acceptable under specific conditions. PR is not cost effective for all Pca patients.

Quality of Life Changes >10 Years After Postoperative Radiation Therapy After Radical Prostatectomy for Prostate Cancer

PURPOSE

To analyze long-term quality-of-life (QoL) changes related to postoperative radiation therapy (RT) after radical prostatectomy.

METHODS AND MATERIALS

Patients who received postoperative 3-dimensional conformal RT in the years 2003 to 2008 with 1.8 to 2.0 Gy fractions up to 66.0 to 66.6 Gy (n = 181) were surveyed using the Expanded Prostate Cancer Index Composite questionnaire before the beginning of RT (A); on the last day (B); and 2 months (C), 1 to 3 years (D), 6 to 9 years (E), and 10 to 13 years (F) after RT.

RESULTS

Mean urinary bother, urinary incontinence bother, and bowel bother score changes (in relation to baseline at time A) of 13, 14, and 7 and 14, 15, and 7 were found at times E and F, respectively (P < .01 for all comparisons). Sexual function scores decreased 6 and 8 points on average (P < .01). Patient age at the time of RT had a considerable impact on urinary bother and urinary incontinence bother, with increasing differences over time when comparing patients aged <68 versus ≥68 years: 0 versus 7 and 0 versus 7 points at time D and 8 versus 23 and 6 versus 35 points at time F, respectively. Patients who did not respond to RT with a decreasing prostate-specific antigen level had greater urinary and urinary incontinence bother and bowel bother score changes >10 years after treatment (25 vs 12; P = .04, 36 vs 10; P = .03, and 20 vs 5; P = .07, respectively). A higher rectal dose was associated with greater acute and long-term bowel bother score decrease. No correlation was found between the dose to the bladder and QoL changes.

CONCLUSIONS

In contrast to early evaluations in the first years, significantly decreasing QoL in the urinary, bowel, and sexual domains was found >5 years after RT. Aging is likely to be a major factor. Younger patients who responded to the treatment had the most favorable long-term QoL results. As 3-dimensional conformal RT was used in this study, intensity modulated concepts could result in improved outcomes.

Postoperative adjuvant and very early salvage radiotherapy after prostatectomy in high-risk prostate cancer patients can improve specific and overall survival

PURPOSE

Adjuvant radiotherapy (ART) for biochemical relapse (BR) after radical prostatectomy (RP) showed increased disease-free survival (DFS) in three previous randomized trials. Retrospective phase II trials evaluated if early salvage RT (ESRT) is equivalent to ART. Our study aims to compare ART and ESRT to salvage RT.

MATERIALS AND METHODS

We compared RP plus ART and ESRT versus SRT. Indication for RT was made by PSA determination after RP: ART when PSA ≤ 0.2 ng/ml, ESRT when PSA ≤ 0.3 after PSA rise from 0.0 to SRT PSA ≥ 0.3. The cause of death of each patients was analyzed, DFS, cause-specific survival (CSS) overall survival (OS) and metastasis-free survival (MFS) in relation to RT intention.

RESULTS

Between 1993 and 2008, 204 patients with a median age of 65 years (44-75) were treated. The median follow-up was 160 months (28.1-273.3). At diagnosis, 89.7% had localized clinical stages and 90.2% had Gleason (G) ≤ 7. The median PSA was 10 (range 4-101). The postoperative G was ≥ 7 in 66.2%; 56.4% had ≥ 2 positive margins; 29.4% received ART, 20% ESRT and 59.3% SRT. The DFS for ART, ESRT and SRT was 74, 56 and 39% with significant differences between the three groups (p < 0.001). ART + ESRT were combined versus SRT; for the DFS, the significant differences (p < 0.001) remained 67% versus 39%. Positive margins, pT3 and pre-RT PSA were significant factors on multivariate analysis. The CSS in the ART + ESRT group was 92 vs. 78% in the SRT group (p < 0.05). OS was 69% in ART + ESRT vs. 57% in SRT (p < 0.05). MFS was 82.7% in ART + ESRT vs. 67.4% in SRT.

CONCLUSIONS

In this study the ART + ESRT presented benefits versus SRT in DFS, CSS, OS and MFS.

Salvage radiotherapy after radical prostatectomy: Long-term results of urinary incontinence, toxicity and treatment outcomes

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We report on long-term toxicity of salvage radiotherapy with a focus on incontinence.

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Salvage radiotherapy results in good long-term biochemical control.

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Toxicity and urinary incontinence rates are high after salvage radiotherapy.

Purpose

For patients with local recurrent disease after radical prostatectomy (35–54%) salvage radiotherapy (SRT) is the treatment of choice. In the post prostatectomy setting, SRT may impose risk at increased toxicity. As data on long-term toxicity, especially on urinary incontinence, are scarce, we report on the long-term treatment outcomes, toxicity and urinary incontinence rates after SRT.

Materials and methods

Patients with biochemically recurrent prostate cancer after radical prostatectomy, who were treated with SRT (3D-CRT) at our institution between 1998 and 2012, were included in this retrospective cohort analysis. Primary endpoint was urinary incontinence rate. Secondary endpoints were acute and late grade ≥2 genitourinary (GU) and gastrointestinal (GI) toxicity rates, biochemical progression-free survival (bPFS), distant metastasis-free survival (DMFS), disease specific survival (DSS), and overall survival (OS).

Results

244 patients were included. Median follow-up after SRT was 50 months (range: 4–187 months). Before start of SRT 69.7% of patients were continent for urine. After SRT de novo urinary incontinence complaints (grade ≥ 1) occurred in the respective acute and late phase in 6.1% and 17.6% of patients. Respective acute grade ≥2 GU and GI toxicity was 19.2% and 17.6%. Late grade ≥2 toxicity for GU was 29.9% and for GI was 21.3%, respectively. The respective 5-year bPFS, OS, DSS and DMFS rates were 47.6%, 91.8%, 98.8% and 80.5%.

Conclusions

Experience at our institution with SRT demonstrates that this results in good long-term biochemical control. However, toxicity and urinary incontinence rates were high.

Results of Dose-adapted Salvage Radiotherapy After Radical Prostatectomy Based on an Endorectal MRI Target Definition Model

OBJECTIVES

To assess the outcome of patients treated with a dose-adapted salvage radiotherapy (SRT) protocol based on an endorectal magnetic resonance imaging (erMRI) failure definition model after radical prostatectomy (RP).

METHODS

We report on 171 relapsing patients after RP who had undergone an erMRI before SRT. 64 Gy were prescribed to the prostatic bed with, in addition, a boost of 10 Gy to the suspected local relapse as detected on erMRI in 131 patients (76.6%).

RESULTS

The 3-year biochemical relapse-free survival (bRFS), local relapse-free survival, distant metastasis-free survival, cancer-specific survival, and overall survival were 64.2±4.3%, 100%, 85.2±3.2%, 100%, and 99.1±0.9%, respectively. A PSA value >1 ng/mL before salvage (P=0.006) and an absence of biochemical progression during RT (P=0.001) were both independently correlated with bRFS on multivariate analysis. No significant difference in 3-year bRFS was observed between the boost and no-boost groups (68.4±4.6% vs. 49.7±10%, P=0.251).

CONCLUSIONS

A PSA value >1 ng/mL before salvage and a biochemical progression during RT were both independently correlated with worse bRFS after SRT. By using erMRI to select patients who are most likely expected to benefit from dose-escalated SRT protocols, this dose-adapted SRT approach was associated with good biochemical control and outcome, serving as a hypothesis-generating basis for further prospective trials aimed at improving the therapeutic ratio in the salvage setting.

Late urinary morbidity and quality of life after radical prostatectomy and salvage radiotherapy for prostate cancer. Scand J Urol 2017;51:457-463. [PMID: 28748716 DOI: 10.1080/21681805.2017.1354314]

OBJECTIVE

There is a paucity of knowledge of long-term urinary morbidity in patients treated for prostate cancer (PCa) with radical prostatectomy (RP) and salvage radiotherapy (SRT). Improved long-term survival calls for heightened awareness of late effects from radiotherapy after RP. The purpose of this study was to assess late urinary morbidity and its potential impact on quality of life (QoL) in patients treated with RP plus SRT compared with patients treated with RP alone.

MATERIALS AND METHODS

Long-term morbidity and QoL were evaluated using a cross-sectional design with validated questionnaires in urinary morbidity [Danish Prostatic Symptom Score (DAN-PSS)] and QoL [European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire Core 30 (EORTC QLQ-C30)]. Included were a total of 227 patients treated with SRT and 192 treated with RP in the periods 2006-2010 and 2005-2007, respectively.

RESULTS

Weak stream, straining, frequency and nocturia were significantly more prevalent in patients treated with RP + SRT than in patients treated with RP alone. Patients treated with RP + SRT generally suffered from more severe urinary symptoms. The QoL scores of the two treatment groups were not statistically significantly different, but a high level of urinary morbidity was significantly related to decreased QoL (p = 0.000).

CONCLUSIONS

Patients treated with SRT have a higher rate of urinary morbidity than do patients treated with RP alone. Severe urinary morbidity was significantly related to decreased QoL, but did not differ between the two treatment groups.

The dose-response of salvage radiotherapy following radical prostatectomy: A systematic review and meta-analysis

PURPOSE/OBJECTIVES

To date neither the optimal radiotherapy dose nor the existence of a dose-response has been established for salvage RT (SRT).

MATERIALS/METHODS

A systematic review from 1996 to 2015 and meta-analysis was performed to identify the pathologic, clinical and treatment factors associated with relapse-free survival (RFS) after SRT (uniformly defined as a PSA>0.2ng/mL or rising above post-SRT nadir). A sigmoidal dose-response curve was objectively fitted and a non-parametric statistical test used to determine significance.

RESULTS

71 studies (10,034 patients) satisfied the meta-analysis criteria. SRT dose (p=0.0001), PSA prior to SRT (p=0.0009), ECE+ (p=0.039) and SV+ (p=0.046) had significant associations with RFS. Statistical analyses confirmed the independence of SRT dose-response. Omission of series with ADT did not alter results. Dose-response is well fit by a sigmoidal curve (p=0.0001) with a TCD₅₀ of 65.8Gy, with a dose of 70Gy achieving 58.4% RFS vs. 38.5% for 60Gy. A 2.0% [95% CI 1.1-3.2] improvement in RFS is achieved for each Gy. The SRT dose-response remarkably parallels that for definitive RT of localized disease.

CONCLUSIONS

This study provides level 2a evidence for dose-escalated SRT>70Gy. The presence of an SRT dose-response for microscopic disease supports the hypothesis that prostate cancer is inherently radio-resistant.

Contemporary Update of a Multi-Institutional Predictive Nomogram for Salvage Radiotherapy After Radical Prostatectomy

PURPOSE

We aimed to update a previously published, multi-institutional nomogram of outcomes for salvage radiotherapy (SRT) following radical prostatectomy (RP) for prostate cancer, including patients treated in the contemporary era.

METHODS

Individual data from node-negative patients with a detectable post-RP prostate-specific antigen (PSA) treated with SRT with or without concurrent androgen-deprivation therapy (ADT) were obtained from 10 academic institutions. Freedom from biochemical failure (FFBF) and distant metastases (DM) rates were estimated, and predictive nomograms were generated.

RESULTS

Overall, 2,460 patients with a median follow-up of 5 years were included; 599 patients (24%) had a Gleason score (GS) ≤ 6, 1,387 (56%) had a GS of 7, 244 (10%) had a GS of 8, and 230 (9%) had a GS of 9 to 10. There were 1,370 patients (56%) with extraprostatic extension (EPE), 452 (18%) with seminal vesicle invasion (SVI), 1,434 (58%) with positive surgical margins, and 390 (16%) who received ADT (median, 6 months). The median pre-SRT PSA was 0.5 ng/mL (interquartile range, 0.3 to 1.1). The 5-yr FFBF rate was 56% overall, 71% for those with a pre-SRT PSA level of 0.01 to 0.2 ng/mL (n = 441), 63% for those with a PSA of 0.21 to 0.50 ng/mL (n = 822), 54% for those with a PSA of 0.51 to 1.0 ng/mL (n = 533), 43% for those with a PSA of 1.01 to 2.0 ng/mL (n = 341), and 37% for those with a PSA > 2.0 ng/mL (n = 323); P < .001. On multivariable analysis, pre-SRT PSA, GS, EPE, SVI, surgical margins, ADT use, and SRT dose were associated with FFBF. Pre-SRT PSA, GS, SVI, surgical margins, and ADT use were associated with DM, whereas EPE and SRT dose were not. The nomogram concordance indices were 0.68 (FFBF) and 0.74 (DM).

CONCLUSION

Early SRT at low PSA levels after RP is associated with improved FFBF and DM rates. Contemporary nomograms can estimate individual patient outcomes after SRT in the modern era.

Simple diagrammatic method to delineate male urethra in prostate cancer radiotherapy: an MRI based approach

Stereotactic body radiotherapy (SBRT) is being increasingly utilized in the treatment of prostate cancer. With the advent of high-precision radiosurgery systems, it is possible to obtain dose distributions akin to high-dose rate brachytherapy with SBRT. However, urethral toxicity has a significant impact on the quality of life in patients with prostate cancer. Contouring the male urethra on a CT scan is difficult in the absence of an indwelling catheter. In this pictorial essay, we have used the MRI obtained for radiotherapy planning to aid in the delineation of the male urethra and have attempted to define guidelines for the same.

Salvage Radiation Therapy Dose Response for Biochemical Failure of Prostate Cancer After Prostatectomy-A Multi-Institutional Observational Study

PURPOSE

To determine whether a dose-response relationship exists for salvage radiation therapy (RT) of biochemical failure after prostatectomy for prostate cancer.

METHODS AND MATERIALS

Individual data from 1108 patients who underwent salvage RT at 10 academic centers were pooled. The cohort was enriched for selection criteria more likely associated with tumor recurrence in the prostate bed (margin positive and pre-RT prostate-specific antigen [PSA] level of ≤2.0 ng/mL) and without the confounding of planned androgen suppression. The cumulative incidence of biochemical failure and distant metastasis over time was computed, and competing risks hazard regression models were used to investigate the association between potential predictors and these outcomes. The association of radiation dose with outcomes was the primary focus.

RESULTS

With a 65.2-month follow-up duration, the 5- and 10-year estimates of freedom from post-RT biochemical failure (PSA level >0.2 ng/mL and rising) was 63.5% and 49.8%, respectively, and the cumulative incidence of distant metastasis was 12.4% by 10 years. A Gleason score of ≥7, higher pre-RT PSA level, extraprostatic tumor extension, and seminal vesicle invasion were associated with worse biochemical failure and distant metastasis outcomes. A salvage radiation dose of ≥66.0 Gy was associated with a reduced cumulative incidence of biochemical failure, but not of distant metastasis.

CONCLUSIONS

The use of salvage radiation doses of ≥66.0 Gy are supported by evidence presented in the present multicenter pooled analysis of individual patient data. The observational reporting method, limited sample size, few distant metastasis events, modest follow-up duration, and elective use of salvage therapy might have diminished the opportunity to identify an association between the radiation dose and this endpoint.

Acute and late urinary toxicity following radiation in men with an intact prostate gland or after a radical prostatectomy: A secondary analysis of RTOG 94-08 and 96-01

INTRODUCTION

To estimate the contribution of the prostate gland and prostatic urethral inflammation to urinary symptoms after radiation therapy for prostate cancer, we performed a secondary analysis of urinary toxicity after primary radiation to an intact prostate vs. postprostatectomy radiation to the prostatic fossa in protocols RTOG 94-08 and 96-01, respectively.

MATERIALS AND METHODS

Patients randomized to the radiation-alone arms (without hormone therapy) of the 2 trials were evaluated, including 104 men receiving primary prostate radiation to 68.4Gy on RTOG 94-08 and 371 men receiving 64.8Gy to the prostatic fossa on RTOG 96-01. Acute and late urinary toxicity were scored prospectively by RTOG scales. Chi-square test/logistic regression and cumulative incidence approach/Fine-Gray regression model were used for analyses of acute and late toxicity, respectively.

RESULTS

Grade≥2 acute urinary toxicity was significantly higher after primary prostatic radiation compared with postprostatectomy radiation (30.8% vs. 14.0%; P<0.001), but acute grade≥3 toxicity did not differ (3.8% vs. 2.7%; P = 0.54). After adjusting for age, primary radiation resulted in significantly higher grade≥2 acute urinary toxicity (odds ratio = 3.72; 95% CI: 1.65-8.37; P = 0.02). With median follow-up of 7.1 years, late urinary toxicity was not significantly different with primary vs. postprostatectomy radiation (5-year grade≥2: 16.7% vs. 18.3%; P = 0.65; grade≥3: 6.0% vs. 3.3%; P = 0.24).

CONCLUSIONS

Primary radiation to an intact prostate resulted in higher grade≥2 acute urinary toxicity than radiation to the prostatic fossa, with no difference in late urinary toxicity. Thus, a proportion of acute urinary toxicity in men with an intact prostate may be attributable to inflammation of the prostatic gland or urethra.

Factors influencing biochemical recurrence in patients who have received salvage radiotherapy after radical prostatectomy: a systematic review and meta-analysis

Several studies have evaluated the risk factors influencing biochemical recurrence (BCR) of prostate cancer in patients receiving salvage radiotherapy (SRT) for BCR after radical prostatectomy (RP), but the results remain conflicting. In this study, we performed a meta-analysis to resolve this conflict. We searched the following databases: PubMed, Embase, and Web of Science using the following terms in "All fields": "salvage radiation therapy," "salvage IMRT," "S-IMRT," "salvage radiotherapy," "SRT," "radical prostatectomy," "RP," "biochemical recurrence," "BCR," "biochemical relapse." Eleven studies, with a total of 1383 patients, were included in our meta-analysis. Of all the variables, only Gleason score (GS) ≥7 (odds ratio [OR]: 3.82; 95% confidence interval [CI]: 2.60-5.64) and pathological tumor (pT) stage ≥3a (OR: 1.82; 95% CI: 1.36-2.42) were positively correlated with BCR. However, SRT combined with androgen deprivation therapy (ADT) (OR: 0.63; 95% CI: 0.44-0.90) and radiation therapy (RT) dose ≥64 Gy (OR: 0.35; 95% CI: 0.19-0.64) were negatively correlated with BCR. Perineural invasion (OR: 2.64; 95% CI: 1.11-6.26), preoperative prostate-specific antigen (PSA) ≥10 ng ml-1 (OR: 1.36; 95% CI: 0.94-1.96), positive surgical margin (OR: 0.92; 95% CI: 0.7-1.19), and seminal vesicle involvement (SVI) (OR: 1.09; 95% CI: 0.83-1.43) had no effect on BCR. Our meta-analysis indicated that pT stage, GS, RT dose, and SRT combined with ADT may influence BCR, while preoperative PSA, surgical margin, perineural invasion, and SVI have only a weak effect on BCR.

No increase in toxicity of pelvic irradiation when intensity modulation is employed: clinical and dosimetric data of 208 patients treated with post-prostatectomy radiotherapy

OBJECTIVE

To compare the toxicity of image-guided intensity-modulated radiotherapy (IG-IMRT) to the pelvis or prostate bed (PB) only. To test the hypothesis that the potentially injurious effect of pelvic irradiation can be counterbalanced by reduced irradiated normal tissue volume using IG-IMRT.

METHODS

Between February 2010 and February 2012, 208 patients with prostate cancer were treated with adjuvant or salvage IG-IMRT to the PB (102 patients, Group PB) or the pelvis and prostate bed (P) (106 patients, Group P). The Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer criteria were used to evaluate toxicity.

RESULTS

Median follow-up was 27 months. Toxicity G ≥ 2 in Group PB: in the bowel acute and late toxicities were 11.8% and 10%, respectively; urinary acute and late toxicities were 10.8% and 15%, respectively. Toxicity G ≥ 2 in Group P: in the bowel acute and late toxicities were both 13.2%; urinary acute and late toxicities were 13.2% and 15.1%, respectively. No statistical difference in acute or late toxicity between the groups was found (bowel: p = 0.23 and p = 0.89 for acute and late toxicity, respectively; urinary: p = 0.39 and p = 0.66 for acute and late toxicity, respectively). Of the clinical variables, only previous abdominal surgery was correlated with acute bowel toxicity. Dosimetric parameters that correlated with bowel toxicity were identified.

CONCLUSION

The toxicity rates were low and similar in both groups, suggesting that IG-IMRT allows for a safe post-operative irradiation of larger volumes. Further investigation is warranted to exclude bias owing to non-randomized character of the study.

ADVANCES IN KNOWLEDGE

Our report shows that modern radiotherapy technology and careful planning allow maintaining the toxicity of pelvic lymph node treatment at the acceptable level, as it is in the case of PB radiotherapy.

Adjuvant radiotherapy for pathologically advanced prostate cancer improves biochemical recurrence free survival compared to salvage radiotherapy

AIM: To evaluate the long-term outcomes of patients receiving adjuvant and salvage radiotherapy following prostatectomy with adverse pathologic features and an undetectable prostate specific antigen (PSA).

METHODS: A retrospective review was performed of patients who received post-prostatectomy radiation at Loyola University Medical Center between 1992 and 2013. Adverse pathologic features (Gleason score ≥ 8, seminal vesicle invasion, extracapsular extension, pathologic T4 disease, and/or positive surgical margins) and an undetectable PSA following prostatectomy were required for inclusion. Adjuvant patients received therapy with an undetectable PSA, salvage patients following biochemical recurrence (BCR). Post-radiation BCR, overall survival, bone metastases, and initiation of hormonal therapy were assessed. Kaplan-Meier time-to-event analyses and stepwise Cox proportional hazards regression (HR) were performed.

RESULTS: Post-prostatectomy patients (n = 134) received either adjuvant (n = 47) or salvage (n = 87) radiation. Median age at radiotherapy (RT) was 63 years, and median follow-up was 53 mo. Five-year post-radiation BCR-free survival was 78% for adjuvant vs 50% salvage radiotherapy (SRT) (Logrank P = 0.001). Patients with radiation administered following a detectable PSA had an increased risk of BCR compared to undetectable: PSA > 0.0-0.2: HR = 4.1 (95%CI: 1.5-11.2; P = 0.005); PSA > 0.2-1.0: HR = 4.4 (95%CI: 1.6-11.9; P = 0.003); and PSA > 1.0: HR = 52 (95%CI: 12.9-210; P < 0.001). There was no demonstrable difference in rates of overall survival, bone metastases or utilization of hormonal therapy between adjuvant and SRT patients.

CONCLUSION: Adjuvant RT improves BCR-free survival compared to SRT in patients with adverse pathologic features and an undetectable post-prostatectomy PSA.

A phase 2 trial of salvage radiation and concurrent weekly docetaxel after a rising prostate-specific antigen level after radical prostatectomy

PURPOSE/OBJECTIVES

We sought to assess the utility of docetaxel administered concurrently with salvage radiation therapy (SRT) following postprostatectomy biochemical failure (BF).

METHODS AND MATERIALS

Men with postprostatectomy BF were accrued on a single-arm phase 2 clinical trial. SRT doses ranged from 64.8 to 70.2 Gy and were delivered in 1.8-Gy fractions to the prostate bed alone as the clinical target volume with a +1-cm uniform planning target volume expansion. The primary endpoint was progression-free survival at 4 years compared with the Stephenson nomogram estimate. Kaplan-Meier methods were used to assess late toxicity, BF, and distant metastases. An unplanned matched-pair analysis was performed with 19 patients treated with SRT alone.

RESULTS

Nineteen men were accrued and treated. Median follow-up was 4.8 years. Median pre-RT prostate-specific antigen level was 0.7 ng/mL (interquartile range, 0.4-1.3 ng/mL). All 8 cycles of docetaxel were completed in 17 (89%) patients. Acute grade 1-4 toxicities were observed in 79%, 50%, 58%, and 11%, respectively. A total of 68% of acute grade 1 toxicities were related to fatigue, urinary, or bowel symptoms. For grade 2 toxicities, 76% were related to neutropenia, fatigue, or urinary symptoms. Acute grade 3 and 4 toxicities were most commonly neutropenia (84% and 100%, respectively). All late toxicities were grade 1 to 2 with 89% related to bowel or urinary function. Predicted 4-year progression-free survival was 39% and observed was 42% (90% confidence interval [CI], 24-60). Matched-pair analysis demonstrated no significant improvement in BF (P = .96, hazard ratio, 0.98; 90% CI, 0.4-2.3) or distant metastases (P = .09; hazard ratio, 0.3; 90% CI, 0.07-1.2), and no difference between late bowel (P = .60) or urinary toxicity (P = .41).

CONCLUSIONS

Docetaxel can safely be administered concurrently with SRT without significantly impacting posttreatment toxicity. Neutropenia was the most significant acute toxicity. Given the small sample size, no clear clinical benefit was observed. Larger studies are needed to determine the efficacy of concurrent docetaxel in this setting.

Integrating Geriatric Assessment into Decision-Making after Prostatectomy: Adjuvant Radiotherapy, Salvage Radiotherapy, or None?

Despite current advancements in the field, management of older prostate cancer patients still remains a big challenge for Geriatric Oncology. The International Society of Geriatric Oncology (ISGO) has recently updated its recommendations in this area, and these have been widely adopted, notably by the European Association of Urology. This article outlines the principles that should be observed in the management of elderly patients who have recently undergone prostatectomy for malignancy or with a biochemical relapse following prostatectomy. Further therapeutic intervention should not be considered in those patients who are classified as frail in the geriatric assessment. In patients presenting better health conditions, salvage radiotherapy is to be preferred to adjuvant radiotherapy, which is only indicated in certain exceptional cases. Radiotherapy of the operative bed presents a higher risk to the elderly. Additionally, hormone therapy clearly shows higher side effects in older patients and therefore it should not be administered to asymptomatic patients. We propose a decision tree based on the ISGO recommendations, with specific modifications for patients in biochemical relapse.

Low Use of Immediate and Delayed Postoperative Radiation for Prostate Cancer with Adverse Pathological Features

PURPOSE

Level 1 evidence supports immediate radiation in post-prostatectomy patients with adverse pathological features while analogous evidence for delayed radiation is lacking. We evaluated immediate and delayed radiation practice patterns and identified factors affecting their use.

MATERIALS AND METHODS

Using the National Cancer Data Base we identified 57,448 men diagnosed with pT3 disease and/or positive margins from 2004 to 2009. Postoperative radiation use through 2011 was analyzed by time trends and multivariate analysis.

RESULTS

A total of 4,316 men (7.5%) received immediate radiation, 1,637 (2.8%) received delayed radiation and 51,495 (90%) were observed. Immediate and delayed radiation use remained relatively stable except for a small but significant decrease in immediate radiation in 2008. This decrease was associated with a relative increase in delayed radiotherapy. Compared to 2004 men diagnosed in 2007 to 2009 had 1.3-fold to 1.5-fold higher odds of delayed radiation than of immediate radiation (p <0.01). The strongest predictors of immediate radiation were margin status, T stage, N stage, Gleason score and patient age. Men with positive margins, seminal vesicle invasion, nodal disease, or Gleason score 8 or greater and younger men had 2.3-fold to sixfold greater odds of receiving immediate radiation than observation (p <0.01). Men with positive margins, seminal vesicle invasion or nodal metastases were also more likely to receive immediate rather than delayed radiation (p <0.01).

CONCLUSIONS

Post-prostatectomy radiation is performed sparingly. Immediate radiation rates remain low but do not appear to be influenced substantially by delayed radiation use. Consistent with the evidence, patients at high risk for recurrence are more likely to undergo immediate radiation rather than observation or delayed radiation.

A case-matched study of toxicity outcomes after proton therapy and intensity-modulated radiation therapy for prostate cancer

BACKGROUND

The authors assessed whether proton beam therapy (PBT) for prostate cancer (PCa) was associated with differing toxicity compared with intensity-modulated radiation therapy (IMRT) using case-matched analysis.

METHODS

From 2010 to 2012, 394 patients who had localized PCa received 79.2 Gray (Gy) relative biologic effectiveness (RBE) delivered with either PBT (181 patients) or IMRT (213 patients). Patients were case-matched on risk group, age, and prior gastrointestinal (GI) and genitourinary (GU) disorders, resulting in 94 matched pairs. Both exact matching (risk group) and nearest-neighbor matching (age, prior GI/GU disorders) were used. Residual confounding was adjusted for by using multivariable regression. Maximum acute and late GI/GU Common Terminology Criteria for Adverse Events-graded toxicities were compared using univariate and multivariable logistic and Cox regression models, respectively.

RESULTS

Bladder and rectum dosimetry variables were significantly lower for PBT versus IMRT (P ≤ .01). The median follow-up was 47 months (range, 5-65 months) for patients who received IMRT and 29 months (range, 5-50 months) for those who received PBT. On multivariable analysis, which exploited case matching and included direct adjustment for confounders and independent predictors, there were no statistically significant differences between IMRT and PBT in the risk of grade ≥ 2 acute GI toxicity (odds ratio, 0.27; 95% confidence interval [CI], 0.06-1.24; P = .09), grade ≥ 2 acute GU toxicity (odds ratio, 0.69; 95% CI, 0.32-1.51; P = .36), grade ≥ 2 late GU toxicity (hazard ratio, 0.56; 95% CI, 0.22-1.41; P = .22), and grade ≥ 2 late GI toxicity (hazard ratio, 1.24; 95% CI, 0.53-2.94; P = .62).

CONCLUSIONS

In this matched comparison of prospectively collected toxicity data on patients with PCa who received treatment with contemporary IMRT and PBT techniques and similar dose-fractionation schedules, the risks of acute and late GI/GU toxicities did not differ significantly after adjustment for confounders and predictive factors.

Long-term complications in men who have early or late radiotherapy after radical prostatectomy

INTRODUCTION

Choosing adjuvant radiotherapy (RT) or salvage RT after radical prostatectomy (RP) for locally advanced prostate cancer is controversial. Performing RT early after RP may increase the risk of urinary complications compared to RT performed later. We evaluated the urinary complication rates of men treated with surgery followed by early or late RT.

METHODS

Using a retrospective chart review, we compared rates of urinary incontinence (UI), bladder neck contracture (BNC), or urethral stricture in men with prostate cancer treated with early RT (<6 months after RP) or late RT (≥6 months after RP), 3 years after RT.

RESULTS

In total, 652 patients (between 2000 and 2007) underwent early RT (162, 24.8%) or late RT (490, 75.2%) after RP. The mean time to early RT was 3.6 months (range: 1-5 months) and to late RT was 30.1 months (range: 6-171 months). At 3 years post-RT, UI rates were similar in the early RT and the late RT groups (24.5% vs. 23.3%, respectively, p = 0.79). Prior to RT, 27/652 (4%) patients had a BNC and 11/652 (1.7%) had a urethral stricture, of which only 1 BNC persisted at 3 years post-RT. After RT, 17/652 (2.6%) BNC and 4/652 (0.6%) urethral stricture developed; of these, 6 BNC and 2 urethral strictures persisted at 3 years.

CONCLUSION

Rates of UI, BNC, and urethral stricture were similar with early and late RT at 3 years post-RT. These findings suggest that the timing of RT after RP does not alter the incidences of these urinary complications and can aid in the decision-making process regarding adjuvant RT versus salvage RT.

[Postoperative radiotherapy of prostate cancer]

Between 10 and 40% of patients who have undergone a radical prostatectomy may have a biologic recurrence. Local or distant failure represents the possible patterns of relapse. Patients at high-risk for local relapse have extraprostatic disease, positive surgical margins or seminal vesicles infiltration or high Gleason score at pathology. Three phase-III randomized clinical trials have shown that, for these patients, adjuvant irradiation reduces the risk of tumoral progression without higher toxicity. Salvage radiotherapy for late relapse allows a disease control in 60-70% of the cases. Several research in order to improve the therapeutic ratio of the radiotherapy after prostatectomy are evaluate in the French Groupe d'Étude des Tumeurs Urogénitales (Gétug) and of the French association of urology (Afu). The Gétug-Afu 17 trial will provide answers to the question of the optimal moment for postoperative radiotherapy for pT3-4 R1 pN0 Nx patients, with the objective of comparing an immediate treatment to a differed early treatment initiated at biological recurrence. The Gétug-Afu 22 questions the place of a short hormonetherapy combined with image-guided, intensity-modulated radiotherapy (IMRT) in adjuvant situation for a detectable prostate specific antigen (PSA). The implementation of a multicenter quality control within the Gétug-Afu in order to harmonize a modern postoperative radiotherapy will allow the development of a dose escalation IMRT after surgery.

A Phase III trial to investigate the timing of radiotherapy for prostate cancer with high-risk features: background and rationale of the Radiotherapy -- Adjuvant Versus Early Salvage (RAVES) trial

OBJECTIVES

To test the hypothesis that observation with early salvage radiotherapy (SRT) is not inferior to 'standard' treatment with adjuvant RT (ART) with respect to biochemical failure in patients with pT3 disease and/or positive surgical margins (SMs) after radical prostatectomy (RP). To compare the following secondary endpoints between the two arms: patient-reported outcomes, adverse events, biochemical failure-free survival, overall survival, disease-specific survival, time to distant failure, time to local failure, cost utility analysis, quality adjusted life years and time to androgen deprivation.

PATIENTS AND METHODS

The Radiotherapy - Adjuvant Versus Early Salvage (RAVES) trial is a phase III multicentre randomised controlled trial led by the Trans Tasman Radiation Oncology Group (TROG), in collaboration with the Urological Society of Australia and New Zealand (USANZ), and the Australian and New Zealand Urogenital and Prostate Cancer Trials Group (ANZUP). In all, 470 patients are planned to be randomised 1:1 to either ART commenced at ≤4 months of RP (standard of care) or close observation with early SRT triggered by a PSA level of >0.20 ng/mL (experimental arm). Eligible patients have had a RP for adenocarcinoma of the prostate with at least one of the following risk factors: positive SMs ± extraprostatic extension ± seminal vesicle involvement. The postoperative PSA level must be ≤0.10 ng/mL. Rigorous investigator credentialing and a quality assurance programme are designed to promote consistent RT delivery among patients.

RESULTS

Trial is currently underway, with 258 patients randomised as of 31 October 2013. International collaborations have developed, including a planned meta-analysis to be undertaken with the UK Medical Research Council/National Cancer Institute of Canada Clinical Trials Group RADICALS (Radiotherapy and Androgen Deprivation In Combination with Local Surgery) trial and an innovative psycho-oncology sub-study to investigate a patient decision aid resource.

CONCLUSION

On the current evidence available, it remains unclear if ART is equivalent or superior to observation with early SRT.

Intensified adjuvant treatment of prostate carcinoma: feasibility analysis of a phase I/II trial

PURPOSE

To perform a preliminary feasibility acute and late toxicity evaluation of an intensified and modulated adjuvant treatment in prostate cancer (PCa) patients after radical prostatectomy.

MATERIAL AND METHODS

A phase I/II has been designed. Eligible patients were 79 years old or younger, with an ECOG of 0-2, previously untreated, histologically proven prostate adenocarcinoma with no distant metastases, pT2-4 N0-1, and with at least one of the following risk factors: capsular perforation, positive surgical margins, and seminal vesicle invasion. All patients received a minimum dose on tumor bed of 64.8 Gy, or higher dose (70.2 Gy; 85.4%), according to the pathological stage, pelvic lymph nodes irradiation (57.7%), and/or hormonal therapy (69.1%).

RESULTS

123 patients were enrolled and completed the planned treatment, with good tolerance. Median follow-up was 50.6 months. Grade 3 acute toxicity was only 2.4% and 3.3% for genitourinary (GU) and gastrointestinal (GI) tract, respectively. No patient had late grade 3 GI toxicity, and the GU grade 3 toxicity incidence was 5.8% at 5 years. 5-year BDSF was 90.2%.

CONCLUSIONS

A modulated and intensified adjuvant treatment in PCa was feasible in this trial. A further period of observation can provide a complete assessment of late toxicity and confirm the BDSF positive results.

Complications and outcomes of salvage robot-assisted radical prostatectomy: a single-institution experience

OBJECTIVE

To determine the peri-operative outcomes of men undergoing salvage robot-assisted prostatectomy (RARP) and to examine the complications, functional consequences and need for additional treatments after salvage RARP.

PATIENTS AND METHODS

At total of 51 consecutive patients underwent salvage RARP after previous failed local therapy. Biochemical recurrence (BCR) was defined as two postoperative PSA measurements ≥0.2 ng/mL. Complications at any time postoperatively were recorded prospectively using a modified Clavien system. The Kaplan-Meier method was used for survival estimation, and regression models were used to identify the predictors of BCR or progression-free survival (PFS) and complications.

RESULTS

The median age at salvage RARP was 68 years and a median of 68 months had elapsed from the time of primary treatment. The median follow-up was 36 months. The median operation duration was 179 min with a median estimated blood loss of 175 mL. In all, 50% of patients had pathological stage 3 disease and positive surgical margins were found in 31% of patients. The estimated 3-year BCR-free or PFS was 57%. The overall complication rate was 47%, with a 35% major complication rate (Grade III-V). Potency was maintained in 23% of preoperatively potent patients and 45% of all patients regained urinary control. No clinical variables were predictive of major complications, but all patients with postoperative bladder neck contracture were incontinent. A higher PSA level and extracapsular extension were significantly associated with BCR or progression (P < 0.01).

CONCLUSIONS

Salvage RARP provides oncological control with potential avoidance of systemic non-curative therapy. Complication, incontinence and erectile dysfunction rates are significant but frequently correctable. This reinforces the need for proper patient counselling and selection.

Adjuvant versus salvage radiotherapy for high-risk prostate cancer patients

Radiotherapy (RT) after prostatectomy may potentially eradicate any residual localized microscopic disease in the prostate bed. The current dilemma is whether to deliver adjuvant RT solely on the basis of high-risk pathology (pT3 or positive margins), but in the absence of measurable prostate-specific antigen, or whether early salvage radiotherapy (SRT) would yield equivalent outcomes. Although the results of current randomized trials answering this very question remain years away, the best evidence to date supports early SRT as the better strategy. In terms of SRT, the pooled evidence reveals that one should initiate RT at the lowest prostate-specific antigen possible to maximize results. Similarly, the pooled data suggest that there is a dose-response favoring doses >70 Gy to the prostate bed. The evidence regarding the role of androgen deprivation therapy and the use of elective pelvic nodal RT is weak, and ongoing randomized trials are underway. Several clinical scenarios are presented for discussion.

Dose-adapted salvage radiotherapy after radical prostatectomy based on an erMRI target definition model: toxicity analysis

BACKGROUND

To assess treatment tolerance by patients treated with a dose-adapted salvage radiotherapy (SRT) protocol based on an multiparametric endorectal magnetic resonance imaging (erMRI) failure definition model after radical prostatectomy (RP).

MATERIAL AND METHODS

A total of 171 prostate cancer patients recurring after RP undergoing erMRI before SRT were analyzed. A median dose of 64 Gy was delivered to the prostatic bed (PB) with, in addition, a boost of 10 Gy to the suspected relapse as visualized on erMRI in 131 patients (76.6%). Genitourinary (GU) and gastrointestinal (GI) toxicities were scored using the RTOG scale.

RESULTS

Grade ≥ 3 GU and GI acute toxicity were observed in three and zero patients, respectively. The four-year grade ≥ 2 and ≥ 3 late GU and GI toxicity-free survival rates (109 patients with at least two years of follow-up) were 83.9 ± 4.7% and 87.1 ± 4.2%, and 92.1 ± 3.6% and 97.5 ± 1.7%, respectively. Boost (p = 0.048) and grade ≥ 2 acute GU toxicity (p = 0.008) were independently correlated with grade ≥ 2 late GU toxicity on multivariate analysis.

CONCLUSIONS

A dose-adapted, erMRI-based SRT approach treating the PB with a boost to the suspected local recurrence may potentially improve the therapeutic ratio by selecting patients that are most likely expected to benefit from SRT doses above 70 Gy as well as by reducing the size of the highest-dose target volume. Further prospective trials are needed to investigate the use of erMRI in SRT as well as the role of dose-adapted protocols and the best fractionation schedule.

Management of patients with biochemical recurrence after local therapy for prostate cancer

Nearly three-quarters of a million American men who have been treated with prostatectomy and/or radiation therapy experience an increasing prostate-specific antigen level known as biochemical recurrence. Although androgen-deprivation therapy remains a reasonable option for some men with biochemical recurrence, deferring androgen ablation or offering nonhormonal therapies may be appropriate in patients in whom the risk of clinical or metastatic progression and prostate cancer-specific death is low. A risk-stratified approach informed by the patient's prostate-specific antigen kinetics, comorbidities, and personal preferences is recommended to determine the best management approach.

Contemporary issues in radiotherapy for clinically localized prostate cancer

Radiotherapy is a valid curative alternative to surgery for prostate cancer. However, patient selection is critical to ensure patients obtain benefits from therapy delivered with curative intent. Dose-escalated radiation has been shown to improve patient outcomes, facilitated by development of robust image guidance and better target delineation imaging technologies. These concepts have also rekindled interest in hypofractionated radiotherapy in the forms of stereotactic body radiotherapy and brachytherapy. Postprostatectomy radiotherapy also improves long-term biochemical outcome in men at high risk of local recurrence.

Late rectal and bladder toxicity following radiation therapy for prostate cancer: Predictive factors and treatment results

AIM

This study aimed at investigating factors associated to late rectal and bladder toxicity following radiation therapy and the effectiveness of Hyperbaric Oxygen Therapy (HBOT) when toxicity is grade ≥2.

BACKGROUND

Radiation is frequently used for prostate cancer, but a 5-20% incidence of late radiation proctitis and cystitis exists. Some clinical and dosimetric factors have been defined without a full agreement. For patients diagnosed of late chronic proctitis and/or cystitis grade ≥2 treatment is not well defined. Hyperbaric Oxygen Therapy (HBOT) has been used, but its effectiveness is not well known.

MATERIALS AND METHODS

257 patients were treated with radiation therapy for prostate cancer. Clinical, pharmacological and dosimetric parameters were collected. Patients having a grade ≥2 toxicity were treated with HBOT. Results of the intervention were measured by monitoring toxicity by Common Toxicity Criteria v3 (CTCv3).

RESULTS

Late rectal toxicity was related to the volume irradiated, i.e. V50 > 53.64 (p = 0.013); V60 > 38.59% (p = 0.005); V65 > 31.09% (p = 0.002) and V70 > 22.81% (p = 0.012). We could not correlate the volume for bladder. A total of 24 (9.3%) patients experienced a grade ≥2. Only the use of dicumarinic treatment was significant for late rectal toxicity (p = 0.014). A total of 14 patients needed HBOT. Final percentage of patients with a persistent toxicity grade ≥2 was 4.5%.

CONCLUSION

Rectal volume irradiated and dicumarinic treatment were associated to late rectal/bladder toxicity. When toxicity grade ≥2 is diagnosed, HBOT significantly ameliorate symptoms.

The contribution of the cone beam Kv CT (CBKvCT) to the reduction in toxicity of prostate cancer treatment with external 3D radiotherapy

OBJECTIVE

Show that verification through cone beam Kv CT (CBKvCT) in a series of patients treated with 3D external radiotherapy (3DRT) for prostate cancer (PC) is related to a reduction in acute and late toxicity levels.

MATERIALS AND METHOD

A retrospective, non-randomized study of two homogeneous groups of patients treated between 2005 and 2008, 46 were verified using electronic portal devices (EPIDs) and 48 through CBKvCT. They received 3DRT for localized PC (T1-T3N0M0) and were prescribed the same doses. Treatment was simulated and planned with the same criteria with the same equipment with a median follow-up time of 24 months (12-54 months). Urinary and gastrointestinal toxicity was determined using Common Toxicity Criteria scale, version 4 and RTOG scales. Statistical analysis of data was performed where p < 0.005 being significative.

RESULTS AND DISCUSSION

With an overall median follow-up time of 24 months, the levels of proctitis were, respectively, 19.56, 15.21 and 15.2 % in the first group, compared with 4.17, 2.08 and 8.33 % in the second. Statistically, less total and late proctitis, late rectal bleeding, anal fissure, total and acute haematuria, total and acute urinary frequency and total urinary incontinence was observed. No statistically significant evidence of a lowering in toxicity neither in terms of acute and late dysuria nor of a relationship to the TNM, Gleason or PSA or in the grade of stability.

CONCLUSION

Verification through CBKvCT in this series is associated with a statistically significant lowering toxicity. This justifies its use. Greater monitoring would be necessary to assess the impact of verification at the level of biochemical control.

Permanent seed brachytherapy for locally recurrent prostate cancer after radical prostatectomy: a case report and review of the literature

PURPOSE

To describe the management of a patient with locally recurrent prostate cancer in the prostate bed, 10 years after a radical prostatectomy.

METHODS AND MATERIALS

A 71-year-old man had a radical prostatectomy for a Gleason 7 clinical T2a carcinoma of the prostate in 2000. Final pathologic stage was pT3a pN0. Postoperatively his prostate-specific antigen was undetectable, but by 2008 it was 1.0ng/mL and in 2011 it reached to 1.43ng/mL. He was referred for consideration of salvage radiotherapy. Staging workup was negative but transrectal ultrasound revealed a 15cc recurrence in the prostate bed. A combination of external beam radiation therapy (4600/23/4.5 weeks to the pelvis) and a brachytherapy boost (115Gy) was selected for definitive management. Androgen ablation was not used.

RESULTS

The treatment was well tolerated. The brachytherapy boost was planned in a similar fashion to a de novo implant for an intact prostate. The postimplant dosimetry was evaluated using magnetic resonance imaging-computed tomography (MR-CT) fusion and appeared satisfactory. Acute toxicity was minimal. Six months after brachytherapy, the prostate-specific antigen had fallen from 1.43 to 0.05ng/mL.

CONCLUSIONS

Dose escalation with combined external beam and brachytherapy may be feasible if recurrent disease can be visualized using transrectal ultrasound and encompassed in an implanted volume. Although longer followup and a larger series of patients are required to demonstrate safety and efficacy, consideration should be given this approach.

[Organ-limited prostate cancer with positive resection margins. Importance of adjuvant radiation therapy]

For pT3 prostate cancer with positive resection margins, the importance of postoperative radiation therapy is confirmed by a high level of evidence. However, for the pT2,R1 situation prospective, randomized studies concerning this question are lacking. Despite better local tumor control in the pT2 stage the PSA recurrence rate lies between 25% and 40% and positive margins are an independent factor for recurrence. Retrospective studies suggest a positive effect of adjuvant or salvage radiation for the oncological outcome in the pT2,R1 situation. On the other hand the side effects profile, with a potentially negative influence of postoperative continence and various delayed toxicities, is not insignificant despite modern radiation techniques and in the era of ultrasensitive PSA analysis should be considered in the risk-benefit assessment. As long as the optimal initiation of postoperative radiation therapy is unclear, the assessment of indications for adjuvant or salvage radiation for organ-limited prostate cancer with positive resection margins should be made after an individual patient consultation and under consideration of the recurrence risk factors, such as the Gleason grade and the localization and extent of the resection margins.

Three Years of Salvage IMRT for Prostate Cancer: Results of the Montpellier Cancer Center

Background. To assess the feasibility of salvage intensity-modulated radiation Therapy (IMRT) and to examine clinical outcome. Patients and Methods. 57 patients were treated with salvage IMRT to the prostate bed in our center from January, 2007, to February, 2010. The mean prescription dose was 68 Gy in 34 fractions. Forty-four patients received concomitant androgen deprivation. Results. Doses to organs at risk were low without altering target volume coverage. Salvage IMRT was feasible without any grade 3 or 4 acute gastrointestinal or urinary toxicity. With a median follow-up of 21 months, one grade 2 urinary and 1 grade ≥2 rectal late toxicities were reported. Biological relapse-free survival was 96.5% (2.3% (1/44) relapsed with androgen suppression and 7.7% (1/13) without). Conclusion. Salvage IMRT is feasible and results in low acute and chronic side-effects. Longer follow-up is warranted to draw conclusions in terms of oncologic control.

Post-prostatectomy image-guided radiation therapy: evaluation of toxicity and inter-fraction variation using online cone-beam CT

PURPOSE

The purpose of this study is to assess the acute and late genitourinary (GU) and gastrointestinal (GI) toxicities of cone-beam computed tomography (CBCT) guided conformal adjuvant and salvage post-prostatectomy radiotherapy (RT) compared with RT with port films.

MATERIALS AND METHODS

Sixty-eight patients (group 1) were treated with RT following radical prostatectomy (RP) using CBCT-guided conformal RT to a median dose of 68.4Gy. CBCT images were acquired three to five times weekly and were automatically co-registered to a reference CT. A comparative group (group 2) included 150 patients who received post-RP RT with weekly port films to a median dose of 64.8Gy. GU and GI toxicities were graded in both the acute and late settings using Radiation Therapy Oncology Group criteria. Associations between toxicity and study variables were evaluated by odds ratios (ORs) estimated by logistic regression.

RESULTS

Grades 2 and 3 acute GU toxicity were experienced by 13% (n=9) and 2% (n=1) of patients in group 1, respectively, while 13% (n=19) had grade 2 acute GU toxicity in the control group (group 2). Grade 2 acute GI toxicity was experienced by 13% (n=9) and 15% (n=23) in groups 1 and 2, respectively. Acute GU (P=0.67) and GI (P =0.84) toxicities were not significantly different between the two groups. There were no associations detected between CBCT and acute GI toxicity (OR 0.76, P=0.57) or acute GU (OR 1.16, P=0.75). Increased odds of acute GU toxicity were observed for doses>68.4Gy (OR 12.81, P=0.04), which were only delivered in the CBCT group. CBCT mean variations (standard deviation) for 1053 fractions were 2.8mm (2.8), 2.0mm (2.4) and 3.1mm (2.9) in the left-to-right, anterior-to-posterior (AP) and superior-to-inferior (SI) axes, respectively. Corrective shifts for variance≥5mm were required for 15%, 6% and 19% of fractions in the left-to-right, anterior-to-posterior and superior-to-inferior axes, respectively.

CONCLUSIONS

Rates of acute toxicity with CBCT-guided post-RP RT to 68.4Gy were similar to treatment to 64.8Gy without image-guidance RT. Acceptable early toxicity profiles suggest that CBCT is a reasonable strategy for image guidance, but the value of CBCT must be weighed against potential increased risk of secondary cancers due to increased radiation exposure.

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.