Sooner or later? Outcome analysis of 431 prostate cancer patients treated with postoperative or salvage radiotherapy

Finding safe dose-volume constraints for re-irradiation with SBRT of patients with prostate cancer relapse: The IEO experience

AIM

The primary aim of this study is to provide preliminary indications for safe constraints of rectum and bladder in patients re-irradiated with stereotactic body RT (SBRT).

METHODS

Data from patients treated for prostate cancer (PCa) and intraprostatic relapse, from 1998 to 2016, were retrospectively collected. First RT course was delivered with 3D conformal RT techniques, SBRT or volumetric modulated arc therapy (VMAT). All patients underwent re-irradiation with SBRT with heavy hypofractionated schedules. Cumulative dose-volume values to organs at risk (OARs) were computed and possible correlation with developed toxicities was investigated.

RESULTS

Twenty-six patients were included. Median age at re-irradiation was 75 years, mean interval between the two RT courses was 5.6 years and the median follow-up was 47.7 months (13.4-114.3 months). After re-irradiation, acute and late G ≥ 2 GU toxicity events were reported in 3 (12%) and 10 (38%) patients, respectively, while late G ≥ 2 GI events were reported in 4 (15%) patients. No acute G ≥ 2 GI side effects were registered. Patients receiving an equivalent uniform dose of the two RT treatments < 131 Gy appeared to be at higher risk of progression (4-yr b-PFS: 19% vs 33%, p = 0.145). Cumulative re-irradiation constraints that appear to be safe are D_30% < 57.9 Gy for bladder and D_30% < 66.0 Gy, D_60% < 38.0 Gy and V_{122.1 Gy} < 5% for rectum.

CONCLUSION

Preliminary re-irradiation constraints for bladder and rectum have been reported. Our preliminary investigation may serve to clear some grey areas of PCa re-irradiation.

Use of combined androgen deprivation therapy with postoperative radiation treatment for prostate cancer: Impact of randomized trials on clinical practice

PURPOSE

To assess the impact of RTOG-9601 and GETUG-AFU-16 on the routine use of combination androgen deprivation therapy (ADT) with postoperative radiotherapy (PORT) for prostate cancer (CaP).

MATERIAL AND METHODS

Patients with localized CaP treated with radical prostatectomy (RP) and PORT with or without ADT at a comprehensive cancer center from January 2006 to June 2007 (Period 1 = P1), July 2011 to December 2012 (Period 2 = P2), and January 2017 to June 2018 (Period 3 = P3) were included. Clinicopathologic features and treatment characteristics were analyzed and compared. Multivariable logistic regression was used to assess prognostic factors and association with ADT use. Statistical tests were two-sided and a P value <0.05 was considered significant. To validate the findings, United States National Cancer Database (NCDB) and Surveillance, Epidemiology, and End Results (SEER) data were collected to assess rates of combined ADT and PORT from 2004 to 2015.

RESULTS

Five hundred and two patients were included: 152 (P1), 185 (P2), and 165 (P3). PORT was most commonly delivered as early SRT (delivered >1 year post-RP with undetectable PSA or PSA >0.05 and ≤0.5 ng/ml) in all periods. The use of combination PORT and ADT increased over time: 14.5% (P1), 32% (P2), and 41% (P3) (P < 0.001). The proportion of patients that met eligibility criteria for either GETUG-AFU-16 or RTOG-9601 decreased from 47% (P1) to 35% (P3) (P = 0.04). International Society of Urological Pathology grade ≥4 (P < 0.002) and pre-PORT PSA >0.5 ng/ml (P < 0.001) were associated with use of ADT. Positive surgical margin status had a negative association (RR 0.5, P < 0.002). The NCDB demonstrated similar trends for use of combined ADT with PORT, increasing from 37% to 49% from 2004 to 2015.

CONCLUSION

The use of combined ADT with PORT increased over time. However, only a third of contemporary patients undergoing PORT are represented in the major trials supporting the evidence for combination treatment, highlighting the need to characterize the modern impact of this intensification strategy.

Adjuvant versus early salvage radiotherapy: outcome of patients with prostate cancer treated with postoperative radiotherapy after radical prostatectomy

Background

Adjuvant (ART) and salvage radiotherapy (SRT) are two common concepts to enhance biochemical relapse free survival (BCRFS) in patients with prostate cancer (PC). We analyzed differences in outcome between ART and SRT in patients with steep decline of PSA-levels after surgery to compare outcome.

Methods

We evaluated 253 patients treated with postoperative RT with a median age of 66 years (range 42–85 years) treated between 2004 and 2014. Patients with additive radiotherapy due to PSA persistence and patients in the SRT group, who did not achieve a postoperative PSA level <0.1 ng/mL were excluded. Hence, data of 179 patients was evaluated. We used propensity score matching to build homogenous groups. A Cox regression model was used to determine differences between treatment options. Median follow-up was 32.5 months (range 1.4–128.0 months).

Results

Early SRT at PSA levels <0.3 ng/mL was associated with significant longer BCRFS than late SRT (HR: 0.32, 95%-CI: 0.14–0.75, p = 0.009). Multiple Cox regression showed pre-RT PSA level, tumor stage, and Gleason score as predictive factors for biochemical relapse. In the overall group, patients treated with either ART or early SRT showed no significant difference in BCRFS (HR: 0.17, 95%-CI: 0.02–1.44, p = 0.1). In patients with locally advanced PC (pT3/4) BCRFS was similar in both groups as well (HR: 0.21, 95%-CI:0.02–1.79, p = 0.15).

Conclusion

For patients with PSA-triggered follow-up, close observation is essential and early initiation of local treatment at low PSA levels (<0.3 ng/mL) is beneficial. Our data suggest, that SRT administered at early PSA rise might be equieffective to postoperative ART in patients with locally advanced PC. However, the individual treatment decision must be based on any adverse risk factors and the patients’ postoperative clinical condition.

Study registration

The present work is approved by the Ethics Commission of the Technical University of Munich (TUM) and is registered with the project number 320/14.

The prognosis benefits of adjuvant versus salvage radiotherapy for patients after radical prostatectomy with adverse pathological features: a systematic review and meta-analysis

Background

The appropriate timing of radiotherapy (RT) for patients after radical prostatectomy (RP) with adverse pathological features (APFs) remains controversial. This systematic review was conducted to compare the efficacy of adjuvant radiotherapy (ART) and salvage radiotherapy (SRT).

Methods

PubMed, EMBASE, Web of Science and the Cochrane Library electronic databases were searched to retrieve the required. The hazard ratio (HR) and corresponding 95% confidence interval (CI) of overall survival (OS), biochemical recurrence-free survival (BRFS) and distant metastases-free survival (DMFS) were extracted. The survival benefits of ART with SRT (including early salvage radiotherapy (ESRT)) were analyzed. The process of the meta-analysis was performed with RevMan version 5.3.

Results

A total of fifteen retrospective studies were finally included in the final analysis including 5586 patients. The pooled analysis indicated that ART could achieve better control of prostate cancer and improve OS (p = 0.0006), BRFS (p < 0.0001) and DMFS (p < 0.0001), when compared to SRT. The subgroup analysis of the 5-year OS rate demonstrated that the ART group still had survival advantages compared to the SRT group (p = 0.0006). However, ART and SRT were comparable in 10-year OS rate (p = 0.07). ART had advantages over SRT in both 5-year (p = 0.0003) and 10-year BRFS (p = 0.0003). The subgroup analysis with different follow-up starting points from RP or RT was essentially consistent with the above results. The pooled analysis also showed that ART was superior to ESRT on OS (p = 0.008) and DMFS (p = 0.03), and comparable to ESRT on BRFS (p = 0.1).

Conclusions

According to this meta-analysis, ART could be served as a preferential treatment for patients with APFs after RP to improve prognosis. Certainly, high-quality, multicenter randomized controlled trials (RCTs) are expecting to confirm the outcomes of our meta-analysis in the future.

Early and late toxicity profiles of patients receiving immediate postoperative radiotherapy versus salvage radiotherapy for prostate cancer after prostatectomy

PURPOSE

The present study aims to evaluate both early and late toxicity profiles of patients receiving immediate postoperative radiotherapy (RT; adjuvant RT or additive RT) compared to salvage RT.

METHODS

We evaluated 253 patients with prostate cancer treated with either immediate postoperative (adjuvant RT, n = 42; additive RT, n = 39) or salvage RT (n = 137). Thirty-five patients received salvage treatment but did not achieve a postoperative prostate specific antigen (PSA) level <0.1 ng/ml and thus were excluded from analysis.

RESULTS

A significantly higher rate of early grade 1/2 proctitis in the immediate postoperative RT group without additional pelvic RT was observed (p = 0.02). Patients in the immediate postoperative RT group without additional pelvic RT showed significantly more early urinary tract obstructions (p = 0.003). Toxicity rates of early (<3 months) and late (3-6 months) postoperative RT were similar (p > 0.05). Baseline recovery rate of erectile dysfunction was better in patients with immediate postoperative RT without additional pelvic RT (p = 0.02; hazard ratio (HR) = 2.22, 95%-confidence interval, 95%-CI: 1.12-4.37). Recovery rate of urinary incontinence showed no significant difference in all groups (p > 0.05).

CONCLUSION

Patients receiving immediate postoperative RT (adjuvant or additive RT) without additional pelvic RT experience early gastrointestinal (GI) side effect proctitis and, as well as early genitourinary (GU) toxicity urinary tract obstruction more frequently than patients treated with salvage RT. Therefore, complete recovery after surgery is essential. However, we suggest basing the treatment decision on the patient's postoperative clinical condition and evaluation of any adverse risk factors, since many studies demonstrate a clear benefit for immediate postoperative RT (adjuvant or additive RT) in terms of oncological outcome.

Adjuvant Versus Early Salvage Radiation Therapy Following Radical Prostatectomy for Men with Localized Prostate Cancer

Radical prostatectomy (RP) is now the most common definitive treatment for high-risk prostate cancer. Unfortunately, many men will have residual microscopic disease after surgery alone. Despite level 1 evidence supporting the use of adjuvant radiation therapy (ART), <10% of men with adverse pathology (positive margins or T3 disease) receive ART in the USA. Early salvage radiation therapy (eSRT) at the time of biochemical recurrence has been proposed as an alternative strategy despite the lack of published randomized trials to support this approach. Multiple randomized trials are ongoing or recently completed to compare ART to eSRT, but given the long natural history of prostate cancer, long-term oncologic outcomes from these trials will not be reported for several years. In this review, we discuss the shifting trends in the diagnosis of high-risk prostate cancer given a decline in PSA screening, use of RP for high-risk disease, and compare and contrast the retrospective and randomized evidence regarding ART and SRT.

Postoperative Radiotherapy in Prostate Cancer: Acquired Certainties and Still Open Issues. A Review of Recent Literature

It is recognized that radiation therapy can eradicate microscopic tumor disease, even in postoperative prostate cancer patients, when extracapsular extension, positive surgical margins or increased prostate-specific antigen is found in surgical specimens. This review of recent literature analyzes and discusses acquired certainties and still open questions regarding type, timing, doses, techniques, toxicities, and associated hormonal therapies of radiotherapy prescribed after radical prostatectomy. Free full text available at www.tumorionline.it

Impact of dose intensified salvage radiation therapy on urinary continence recovery after radical prostatectomy: Results of the randomized trial SAKK 09/10

INTRODUCTION

Adjuvant radiation therapy (aRT) after radical prostatectomy (RP) is associated with impaired urinary continence recovery as compared to surveillance. Less is known regarding the effect of salvage radiation therapy (sRT) dose intensification on continence outcomes.

MATERIALS AND METHODS

Urinary continence recovery was investigated within a multicentre randomized trial in biochemically recurrent prostate cancer patients who received either 64 Gy (32 fractions) or 70 Gy (35 fractions) sRT. Incontinence was assessed using Common Toxicity Criteria for Adverse Events v4.0 at baseline, at the end of sRT and 3 months afterward. Quality of life (QoL) was assessed with the EORTC QoL questionnaires C30 and PR25 at baseline and 3 months after completion of sRT. A total of 344 patients were evaluable.

RESULTS

At baseline 233 (68%) of patients were fully continent and 14% in both arms became incontinent three months after treatment. Of the remaining 111 (32%) patients being incontinent at baseline, continence recovery was achieved 3 months after sRT by 44% vs. 41% with 64 vs. 70 Gy, respectively (p = 0.8). This analysis is limited by its short follow-up.

CONCLUSIONS

Dose intensification of sRT had no impact on early urinary continence recovery or prevalence of de novo incontinence.

Post-prostatectomy radiation therapy for locally recurrent prostate cancer

INTRODUCTION

Approximately 15-30% of men with localized prostate cancer will experience biochemical recurrence (BCR) after radical prostatectomy. Postoperative radiation therapy is used in men with adverse pathological features to reduce the risk of BCR or with curative intent in men with known BCR. In this study, we review the evidence for the adjuvant and salvage radiation therapy after radical prostatectomy. Areas covered: A literature review of the Medline and Embase databases was performed. The search strategy included the following terms: prostate cancer, adjuvant radiotherapy, salvage radiotherapy, radical prostatectomy, biochemical recurrence, and prostate cancer recurrence. Prospective randomized trials for the adjuvant radiotherapy and observational studies supporting salvage radiotherapy were included for discussion. Expert commentary: As postoperative radiotherapy is associated with non-trivial risks of acute and long-term toxicity and given the absence of compelling data supporting adjuvant over early salvage radiotherapy, the authors advocate, with rare exceptions, close observation and timely (early) salvage radiotherapy for patients with BCR and long life expectancy. Adjuvant radiotherapy may be considered in patients at high-risk for recurrence. Observation is appropriate in patients with limited life expectancy and/or absence of adverse features.

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.

Adjuvant versus salvage radiotherapy in prostate cancer: multi-institutional retrospective analysis of the Spanish RECAP database

PURPOSE

To compare adjuvant radiotherapy (ART) to salvage radiotherapy (SRT) after radical prostatectomy (RP) in a cohort of prostate cancer (PCa) patients. The primary aim was to comparatively assess 2- and 5-year biochemical relapse-free survival (BRFS). A secondary aim was to identify predictors of survival.

PATIENTS AND METHODS

Data were acquired from the RECAP database, a population-based prostate cancer registry in Spain. Inclusion criteria included RP (with or without lymphadenectomy) followed by ART or SRT. A total of 702 patients were analyzed. Pre-RT PSA values (>0.5 vs. ≤0.5 ng/ml), pathological stage (T1-2 vs. T3-4), post-surgical Gleason score (≤7 vs. 8-10), margin status (positive vs. negative), hormonal treatment (yes vs. no), and RT dose (≤66 Gy vs. >66 Gy) were evaluated to assess their impact on BRFS.

RESULTS

The mean patient age in the ART and SRT groups, respectively, was 64 years (range 42-82) and 64.8 years (range 42-82). Median follow-up after RT in the whole sample was 34 months (range 3-141). A total of 702 patients were included: 223 (31.8%) received ART and 479 (68.2%) SRT. BRFS rates (95% CI) in the ART and SRT groups at months 24 and 60 were, respectively: 98.1% (95.9-100.0%) vs. 91.2% (88.2-94.2%) and 84.5% (76.4-92.6%) vs. 74.0% (67.4-80.7%) (p = 0.004). No significant differences in OS were observed (p = 0.053). The following variables were significant predictors of biochemical recurrence in the SRT group: (1) positive surgical margin status (p = 0.049); (2) no hormonotherapy (p = 0.03); (3) total prostate dose ≤66 Gy (p = 0.004); and pre-RT PSA ≥0.5 ng/ml (p = 0.013).

CONCLUSIONS

This is the first nationwide study in Spain to evaluate a large cohort of PCa patients treated with RP followed by postoperative RT. ART yielded better 2- and 5-year BRFS rates, although OS was equivalent. These findings are consistent with most other published studies and support ART in patients with adverse prognostic characteristics after radical prostatectomy. Prospective trials are needed to compare immediate ART to early SRT to better determine their relative benefits.

Adjuvant and Salvage Radiotherapy after Radical Prostatectomy in Prostate Cancer Patients

CONTEXT

Prostate cancer (PCa) patients found to have adverse pathologic features following radical prostatectomy (RP) are less likely to be cured with surgery alone.

OBJECTIVE

To analyze the role of postoperative radiotherapy (RT) in patients with aggressive PCa.

EVIDENCE ACQUISITION

We performed a systematic literature review of the Medline and EMBASE databases. The search strategy included the terms radical prostatectomy, adjuvant radiotherapy, and salvage radiotherapy, alone or in combination. We limited our search to studies published between January 2009 and August 2016.

EVIDENCE SYNTHESIS

Three randomized trials demonstrated that immediate RT after RP reduces the risk of recurrence in patients with aggressive PCa. However, immediate postoperative RT is associated with an increased risk of acute and late side effects ranging from 15% to 35% and 2% to 8%, respectively. Retrospective studies support the oncologic efficacy of initial observation followed by salvage RT administered at the first sign of recurrence; however, the impact of this delay on long-term control remains uncertain. Hopefully, ongoing randomized trials will shed light on the role of adjuvant RT versus observation±salvage RT in individuals with adverse features at RP. Accurate patient selection based on clinical characteristics and molecular profile is crucial. Dose escalation, whole-pelvis RT, novel techniques, and the use of hormonal therapy might improve the outcomes of postoperative RT.

CONCLUSIONS

Immediate RT reduces the risk of recurrence after RP in patients with aggressive disease. However, this approach is associated with an increase in the incidence of short- and long-term side effects. Observation followed by salvage RT administered at the first sign of recurrence might be associated with durable cancer control, but prospective randomized comparison with adjuvant RT is still awaited. Dose escalation, refinements in the technique, and the concomitant use of hormonal therapies might improve outcomes of patients undergoing postoperative RT.

PATIENT SUMMARY

Postoperative radiotherapy has an impact on oncologic outcomes in patients with aggressive disease characteristics. Salvage radiotherapy administered at the first sign of recurrence might be associated with durable cancer control in selected patients but might compromise cure in others.

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.

Radiation Therapy after Radical Prostatectomy: Implications for Clinicians

Depending on the pathological findings, up to 60% of prostate cancer patients who undergo radical prostatectomy (RP) will develop biochemical relapse and require further local treatment. Radiotherapy (RT) immediately after RP may potentially eradicate any residual localized microscopic disease in the prostate bed, and it is associated with improved biochemical, clinical progression-free survival, and overall survival in patients with high-risk pathological features according to published randomized trials. Offering immediate adjuvant RT to all men with high-risk pathological factors we are over-treating around 50% of patients who would anyway be cancer-free, exposing them to unnecessary toxicity and adding costs to the health-care system. The current dilemma is, thus, whether to deliver adjuvant immediate RT solely on the basis of high-risk pathology, but in the absence of measurable prostate-specific antigen, or whether early salvage radiotherapy would yield equivalent outcomes. Randomized trials are ongoing to definitely answer this question. Retrospective analyses suggest that there is a dose–response favoring doses >70 Gy to the prostate bed. The evidence regarding the role of androgen deprivation therapy is emerging, and ongoing randomized trials are underway.

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.

Continuous prostate-specific antigen rise despite salvage radiotherapy following radical prostatectomy: Pattern of clinical relapse and predictive factors

Salvage radiotherapy for post-prostatectomy biochemical recurrence does not always control the disease. It would be useful to identify patients who would not benefit from radiotherapy to the prostate bed prior to making treatment recommendations. One such group of patients is those who experience continuously rising prostate-specific antigen (PSA) despite radiotherapy. The purpose of this study was to identify risk factors for continuous PSA increase and the pattern of radiological relapse during follow-up. We performed a retrospective comparison of two patient groups with PSA decline or continuous increase following salvage radiotherapy to the prostate bed. All patients received 3-D conformal radiotherapy (35 fractions of 2 Gy). Patients with continuous PSA increase were more likely to have had complete surgical resection (negative margins) and a shorter interval to radiotherapy (<24 months). However, the only statistically significant risk factor was Gleason score. Sixty-four percent of patients with a Gleason score of 9 developed continuously increasing PSA, indicating that residual subclinical cancer was not located in the prostate bed. The median time to radiological recurrence was 43 months. Isolated pelvic nodal recurrence was uncommon. Almost all patients with radiological recurrence had high-risk disease, in particular stage pT3. In conclusion, the majority of patients with biologically aggressive tumors with Gleason score 9 were not adequately treated with prostate bed radiotherapy alone. The predominant pattern of radiological recurrence was outside of the pelvis. Therefore, the problem of distant micrometastases has to be addressed.

Radiotherapy in Prostate Cancer Patients With Pelvic Lymphocele After Surgery: Clinical and Dosimetric Data of 30 Patients

INTRODUCTION

The purpose of the study was to evaluate the feasibility of irradiation after prostatectomy in the presence of asymptomatic pelvic lymphocele.

PATIENTS AND METHODS

The inclusion criteria for this study were: (1) patients referred for postoperative (adjuvant or salvage) intensity modulated radiotherapy (IMRT; 66-69 Gy in 30 fractions); (2) detection of postoperative pelvic lymphocele at the simulation computed tomography [CT] scan; (3) no clinical symptoms; and (4) written informed consent. Radiotherapy toxicity and occurrence of symptoms or complications of lymphocele were analyzed. Dosimetric data (IMRT plans) and the modification of lymphocele volume during radiotherapy (cone beam CT [CBCT] scan) were evaluated.

RESULTS

Between January 2011 and July 2013, in 30 of 308 patients (10%) treated with radiotherapy after prostatectomy, pelvic lymphocele was detected on the simulation CT. The median lymphocele volume was 47 cm(3) (range, 6-467.3 cm(3)). Lymphocele was not included in planning target volume (PTV) in 8 cases (27%). Maximum dose to lymphocele was 57 Gy (range, 5.7-73.3 Gy). Radiotherapy was well tolerated. In all but 2 patients, lymphoceles remained asymptomatic. Lymphocele drainage-because of symptom occurrence-had to be performed in 2 patients during IMRT and in one patient, 7 weeks after IMRT. CBCT at the end of IMRT showed reduction in lymphocele volume and position compared with the initial data (median reduction of 37%), more pronounced in lymphoceles included in PTV.

CONCLUSION

Radiotherapy after prostatectomy in the presence of pelvic asymptomatic lymphocele is feasible with acceptable acute and late toxicity. The volume of lymphoceles decreased during radiotherapy and this phenomenon might require intermediate radiotherapy plan evaluation.

Adjuvant and salvage radiotherapy after prostatectomy: a systematic review and meta-analysis

PURPOSE

In men with adverse prognostic factors (APFs) after radical prostatectomy (RP), the most appropriate timing to administer radiotherapy remains a subject for debate. We conducted a systemic review and meta-analysis to evaluate the therapeutic strategies: adjuvant radiotherapy (ART) and salvage radiotherapy (SRT).

MATERIALS AND METHODS

We comprehensively searched PubMed, EMBASE, Web of Science and the Cochrane Library and performed the meta-analysis of all randomized controlled trials (RCTs) and retrospective comparative studies assessing the prognostic factors of ART and SRT.

RESULTS

Between May 1998 and July 2012, 2 matched control studies and 16 retrospective studies including a total of 2629 cases were identified (1404 cases for ART and 1185 cases for SRT). 5-year biochemical failure free survival (BFFS) for ART was longer than that for SRT (Hazard Ratio [HR]: 0.37; 95% CI, 0.30-0.46; p<0.00001, I(2) = 0%). 3-year BFFS was significantly longer in the ART (HR: 0.38; 95% CI, 0.28-0.52; p<0.00001, I(2) = 0%). Overall survival (OS) was also better in the ART (RR: 0.53; 95% CI, 0.41-0.68; p<0.00001, I(2) = 0%), as did disease free survival (DFS) (RR: 0.53; 95% CI, 0.43-0.66; p<0.00001, I(2)  = 0%). Exploratory subgroup analysis and sensitivity analysis revealed the similar results with original analysis.

CONCLUSION

ART therapy offers a safe and efficient alternative to SRT with longer 3-year and 5-year BFFS, better OS and DFS. Our recommendation is to suggest ART for patients with APFs and may reduce the need for SRT. Given the inherent limitations of the included studies, future well-designed RCTs are awaited to confirm and update this analysis.

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.

Results of radical prostatectomy in newly diagnosed prostate cancer: long-term survival rates in locally advanced and high-risk cancers

BACKGROUND

Until just a few years ago, locally advanced or high-risk prostate cancer was generally considered incurable. Recently, however, evidence has accumulated that, even for these patients, the oncologic outcome after radical prostatectomy is not uniformly poor.

METHODS

13 262 evaluable patients with prostate cancer were treated with radical prostatectomy from 1992 to 2012. 4391 had a locally advanced stage, lymphogenous metastases, and/or unfavorable histopathological tumor characteristics. The endpoints of this retrospective, monocentric study were biochemical recurrence-free survival (postoperative PSA value less than 0.2 ng/mL), carcinoma-specific survival, and overall survival.

RESULTS

The rates of biochemical recurrence-free survival, carcinoma-specific survival, and overall survival at 10 years were 53%, 98%, and 89% for patients with extraprostatic tumor growth (tumor stage pT3a, 2675 patients); 19%, 87%, and 79% for patients with demonstrated invasion of the seminal vesicle (pT3b, 1373 patients); and 3%, 77%, and 69% for patients with tumor invasion of neighboring organs (pT4, 53 patients). The corresponding figures were 14%, 81%, and 71% for patients with lymph node metastases (682 patients); 32%, 93%, and 85% for those with a preoperative PSA value above 20 ng/mL (728 patients); and 25%, 70%, and 58% for those with a prostatectomy Gleason score of 8 or more points (559 patients).

CONCLUSION

Even patients with locally advanced, nodally metastasized, or localized high-risk prostate cancer do not necessarily have a poor outcome. Although most such patients have a biochemical recurrence after radical prostatectomy, their carcinoma-specific mortality within ten years of radical prostatectomy ranges from 2% to 30% depending on the risk constellation, while their overall survival rate over the same period ranges from 58% to 89%.

[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.

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.

Impact of pathological tumor stage for salvage radiotherapy after radical prostatectomy in patients with prostate-specific antigen < 1.0 ng/ml

BACKGROUND

To evaluate prognostic factors in salvage radiotherapy (RT) for patients with pre-RT prostate-specific antigen (PSA) < 1.0 ng/ml.

METHODS

Between January 2000 and December 2009, 102 patients underwent salvage RT for biochemical failure after radical prostatectomy (RP). Re-failure of PSA after salvage RT was defined as a serum PSA value of 0.2 ng/ml or more above the postradiotherapy nadir followed by another higher value, a continued rise in serum PSA despite salvage RT, or initiation of systemic therapy after completion of salvage RT. Biochemical relapse-free survival (bRFS) was estimated using the Kaplan-Meier method. Multivariate analysis was performed using the Cox proportional hazards regression model.

RESULTS

The median follow-up period was 44 months (range, 11-103 months). Forty-three patients experienced PSA re-failure after salvage RT. The 4-year bRFS was 50.9% (95% confidence interval [95% CI]: 39.4-62.5%). In the log-rank test, pT3-4 (p < 0.001) and preoperative PSA (p = 0.037) were selected as significant factors. In multivariate analysis, only pT3-4 was a prognostic factor (hazard ratio: 3.512 [95% CI: 1.535-8.037], p = 0.001). The 4-year bRFS rates for pT1-2 and pT3-4 were 79.2% (95% CI: 66.0-92.3%) and 31.7% (95% CI: 17.0-46.4%), respectively.

CONCLUSIONS

In patients who have received salvage RT after RP with PSA < 1.0 ng/ml, pT stage and preoperative PSA were prognostic factors of bRFS. In particular, pT3-4 had a high risk for biochemical recurrence after salvage RT.

[Tumour recurrence]

In Chap. 6 the German S3 guideline on prostate cancer addresses the issue of tumour recurrence following primary local treatment with curative intent, i.e. after radical prostatectomy or a form of radiotherapy. PSA recurrence after radical surgery is defined as a rising PSA of 0.2 ng/ml and after radiotherapy as an increase of at least 2 ng/ml above the individual nadir. Factors for the clinical judgement that a local recurrence is likely are empirical indicators from the primary tumour diagnosis and the PSA course after primary treatment. Salvage external beam radiotherapy after radical surgery does not require the histological proof of a local recurrence and should be initiated early (PSA < 0.5 ng/ml). Before salvage radical prostatectomy, which carries a higher complication rate, the presence of a local recurrence should be histologically verified.

Evaluation of the dynamic conformal arc therapy in comparison to intensity-modulated radiation therapy in prostate, brain, head-and-neck and spine tumors

To evaluate dynamic conformal arc therapy (DAT) dose distribution and clinical applicability in comparison to intensity‐modulated radiotherapy (IMRT) in different types of tumors and locations, twelve patients with prostate cancer with no node involvement and three patients with single tumors in the pituitary, in the neck and in the thoracic spinal region treated with IMRT, were retrospectively planned with DAT using Eclipse (V8.1). The prostate cases were also planned with three‐dimensional conformal radiation therapy (3DCRT). Dose distributions were evaluated through comparisons of dose‐volumetric histograms and in‐house IMRT protocol constraints, as well as validated via ion chamber array measurements. DAT plans for prostate showed a statistically comparable achievement of tumor conformity and dose sparing for bladder and rectum when compared to IMRT. Dose on femoral heads were similar to those achieved using 3DCRT. DAT could be planned with similar results to those obtained in IMRT for the dose constraints of the defined structures by using a 360° arc for the brain lesion and several arcs including noncoplanar ones for the head‐and‐neck and spinal tumors. Experimental validation of the calculated dose distributions via gamma analysis of composite distributions for DAT provided that more than 95% of the pixels satisfy the criteria 3 mm–3%, which was similar to that of IMRT. The average number of monitor units was approximately five times lower than IMRT. In conclusion, DAT is capable of providing conformal dose distributions to the targets accomplishing many of the IMRT dose constraints simultaneously. Experimental dose‐validation accuracy, ease of planning and reduced treatment times make DAT both acceptable and attractive for clinical use.

PACS numbers: 87.55.D‐, 87.55.dk, 87.55.Qr, 87.56.bd, 87.56.Fc, 87.53.Kn, 87.55. de, 87.55.kd

Clinical factors predicting late severe urinary toxicity after postoperative radiotherapy for prostate carcinoma: a single-institute analysis of 742 patients

PURPOSE

To investigate the clinical factors independently predictive of long-term severe urinary sequelae after postprostatectomy radiotherapy.

PATIENTS AND METHODS

Between 1993 and 2005, 742 consecutive patients underwent postoperative radiotherapy with either adjuvant (n = 556; median radiation dose, 70.2 Gy) or salvage (n = 186; median radiation dose, 72 Gy) intent.

RESULTS

After a median follow-up of 99 months, the 8-year risk of Grade 2 or greater and Grade 3 late urinary toxicity was almost identical (23.9% vs. 23.7% and 12% vs. 10%) in the adjuvant and salvage cohorts, respectively. On univariate analysis, acute toxicity was significantly predictive of late Grade 2 or greater sequelae in both subgroups (p <.0001 in both cases), and hypertension (p = .02) and whole-pelvis radiotherapy (p = .02) correlated significantly in the adjuvant cohort only. The variables predictive of late Grade 3 sequelae were acute Grade 2 or greater toxicity in both groups and whole-pelvis radiotherapy (8-year risk of Grade 3 events, 21% vs. 11%, p = .007), hypertension (8-year risk, 18% vs. 10%, p = .005), age ≤ 62 years at RT (8-year risk, 16% vs. 11%, p = .04) in the adjuvant subset, and radiation dose >72 Gy (8-year risk, 19% vs. 6%, p = .007) and age >71 years (8-year risk, 16% vs. 6%, p = .006) in the salvage subgroup. Multivariate analysis confirmed the independent predictive role of all the covariates indicated as statistically significant on univariate analysis.

CONCLUSIONS

The risk of late Grade 2 or greater and Grade 3 urinary toxicity was almost identical, regardless of the RT intent. In the salvage cohort, older age and greater radiation doses resulted in a worse toxicity profile, and younger, hypertensive patients experienced a greater rate of severe late sequelae in the adjuvant setting. The causes of this latter correlation and apparently different etiopathogenesis of chronic damage in the two subgroups were unclear and deserve additional investigation.

Impact of anatomical interventions on the localization of post-prostatectomy cancer patients

PURPOSE

Anatomical deformations of prostate-bed, rectum, and bladder can compromise the targeting accuracy in post-prostatectomy cancer patients. In this work, the impact of anatomical interventions on the localization data from post-prostatectomy patients who received image-guided IMRT was analyzed.

METHODS

Patients were localized daily with online kilovoltage cone-beam computed tomography (kV-CBCT). The target and the organs at risk (OARs) positional and volumetric changes were evaluated and couch shifts were applied. For patients with large target or OAR volumetric changes, quantified by either a rectal or bladder wall displacement of >5 mm on the CBCT sagittal images compared to the planning CT, repeated localization CBCT scans were performed following an interventional procedure. The procedure involves insertion of a catheter to deflate the rectum, evacuation of stools, and/or adjustment of bladder filling. The required shifts were then evaluated, and the IMRT treatment was subsequently delivered after proper patient positioning. The pre- and post-intervention shifts were compared in the lateral [left-right (LR)], longitudinal [superior-inferior (SI)], and vertical [anterior-posterior (AP)] directions. The percentage of shifts larger than 5 mm in all directions was also compared. Clinical target volume to planning target volume (CTV-to-PTV) expansion margins were estimated based on the pre- and post-intervention localization data.

RESULTS

Intervention was performed on all patients (n=17) treated between October 2008 and March 2009. The number of interventions ranged from 2 to 12 with a median number of 5, resulting in a total of 96 pairs of pre- and post-intervention shifts. The mean value (sigma) and standard deviation (sigma) of the shifts from pre- versus post-intervention data were LR, 0.0 +/- 3.0 mm vs. 0.5 +/- 2.8 mm; SI, 0.2 +/- 3.1 mm vs. -1.0 +/- 2.1 mm; and AP, -2.6 +/- 5.8 mm vs. 1.7 +/- 3.9 mm. The mean 3D shift distance was 7.0 +/- 3.1 mm vs. 5.0 +/- 2.6 mm. The percentage of pre-intervention shifts larger than 5 mm were 7%, 7%, and 45% in the LR, SI, and AP directions, respectively, compared to 8%, 4%, and 21% for post-intervention. Localization data from pre- and post-intervention procedures suggest that treatments that do not include intervention to correct for rectum/bladder anatomical variations require an additional 3.3 mm CTV-to-PTV margin.

CONCLUSIONS

Anatomical interventions reduced the localization errors arising from large volume and shape changes in the rectum and/or bladder compared to treatments without interventions.