Salvage radiotherapy for PSA failure after radical prostatectomy

Italian Survey in Postoperative Radiation Therapy for Prostate Carcinoma by the Airo National Working Group on Prostate Radiotherapy: Definitive Results

Aims and background

The National Working Group on Prostate Radiotherapy of AIRO (Associazione Italiana Radioterapia Oncologica, Italian Association of Radiotherapeutic Oncology) was established in March 2001. A retrospective multicenter survey was performed to analyze the patterns of care for prostate cancer patients treated with postoperative radiotherapy following radical prostatectomy in Italy with regard to the year 2000.

Materials and methods

A structured questionnaire was mailed to 47 Italian radiotherapy centers to assess patient accrual in the postoperative setting in the interval comprised between period January-December 2000. Numbers of patients treated for different stages, specific prognostic factors indicating the need for adjuvant radiotherapy, fractionation schedules and prescription doses were acquired as well as other clinically important factors such as radiotherapy timing and the use of hormone therapy. More technical features of the treatment, such as patient positioning, mode of simulation, typical field setup and dose prescription criteria were also included in the questionnaire.

Results

The questionnaire was returned by 24 radiotherapy Institutions (51%) with a total number of 470 patients treated postoperatively in the year 2000. An average of about 20 patients were enrolled by each radiotherapy center. The age range was 45-81 years. Radiotherapy was delivered within 6 months of radical prostatectomy in 297 patients (65.4%) (mean, 3.4 months). In 157 (34.6%), the treatment was delivered as a salvage approach for biochemical or micro-macroscopic recurrence. Most of patients had locally advanced stage disease (pT3-pT4) (76%). Unfavorable prognostic factors, such as positive margins, capsular invasion, Gleason pattern score <7 were present in about 50% of patients.

Conclusions

The study confirmed that important risk factors for recurrences are present in a significant percentage of patients treated by radical prostatectomy. The number of patients that would benefit from adjuvant radiotherapy is therefore potentially very large. Future prospective studies should be conducted to assess and to clarify the respective roles of adjuvant and salvage radiotherapy in prostate cancer patients.

A phase II randomized placebo-controlled double-blind study of salvage radiation therapy plus placebo versus SRT plus enzalutamide with high-risk PSA-recurrent prostate cancer after radical prostatectomy (SALV-ENZA)

BACKGROUND

In men with a rising PSA following radical prostatectomy, salvage radiation therapy (SRT) offers a second chance for cure. Hormonal therapy can be combined with SRT in order to increase prostate tumor control, albeit with associated higher rates of treatment side effects. This trial studies the effectiveness of SRT combined with hormonal therapy using a more potent anti-androgen with a favorable side effect profile. Enzalutamide, a next generation selective androgen receptor antagonist, is approved by the Food and Drug Administration for the treatment of metastatic castrate-resistant prostate cancer (CRPC) where it has been shown to improve overall survival in combination with androgen deprivation therapy. The primary objective of this study is to evaluate the efficacy of combination SRT and enzalutamide for freedom-from-PSA-progression. Secondary objectives include time to local recurrence within the radiation field, metastasis-free survival and safety as determined by frequency and severity of adverse events.

METHODS/DESIGN

This is a randomized, double-blind, phase II, prospective, multicenter study in adult males with biochemically recurrent prostate cancer following radical prostatectomy. Following registration, enzalutamide 160 mg or placebo by mouth (PO) once daily will be administered for 6 months. Following two months of study drug, external beam radiotherapy to 66.6-70.2 Gray (Gy) will be administered to the prostate bed over 7-8 weeks while continuing daily placebo/enzalutamide. This is followed by two additional months of placebo/enzalutamide.

DISCUSSION

The SALV-ENZA trial is the first phase II placebo-controlled double-blinded randomized study to test SRT in combination with a next generation androgen receptor antagonist in men with high-risk recurrent prostate cancer after radical prostatectomy. The primary hypothesis of this study is that clinical outcomes will be improved by the addition of enzalutamide compared to standard-of-care SRT alone and pave the path for phase III evaluation of this combination.

TRIAL REGISTRATIONS

ClinicaltTrials.gov Identifier: NCT02203695 Date of Registration: 06/16/2014. Date of First Participant Enrollment: 04/16/2015.

Radiotherapy after Prostatectomy

Aims and background

The role of radiotherapy after prostatectomy is controversial. This paper tries to give some guidelines for everyday practice through an analysis of literature data.

Methods

The potential role of radiotherapy in the adjuvant and salvage setting is discussed. We also report and interpret available literature data for both settings.

Results

As regards an increase in or detectable prostate-specific antigen (PSA) after radical prostatectomy, about 40–50% of patients are rendered bNED with local salvage radiotherapy, but only 10–50% are long-term (5 years) biochemically controlled. A timely salvage treatment is crucial to optimize control probability. As regards adjuvant radiotherapy for undetectable postoperative PSA in patients at high risk of failure as judged on pathology, results are more encouraging. Recent data report bNED rates ≥70% at 5 years.

Conclusions

Although results are far from satisfactory, salvage radiotherapy should be considered for every patient with an increased or detectable PSA after surgery. Adjuvant radiotherapy seems preferable to salvage radiotherapy for patients at high (>30%) risk of failure.

Benefit on Biochemical Control of Adjuvant Radiation Therapy in Patients with Pathologically Involved Seminal Vesicles after Radical Prostatectomy

Aims and Background

To determine whether there is a benefit for biochemical control with adjuvant radiation therapy to the surgical bed following radical prostatectomy in patients with seminal vesicle invasion and pathologically negative pelvic lymph nodes (pT3b-pT4 pN0).

Methods

We retrospectively reviewed the clinical records of radical prostatectomy patients treated between 1995 and 2002. A total of 66 patients with seminal vesicle invasion were identified: 45 of these patients received adjuvant radiation therapy and 21 were observed. Radiation therapy was initiated within 4 months of prostatectomy. Median dose was 66 Gy (range, 60–70 Gy). Median follow-up from the day of surgery was 40.6 months (mean, 41.5; range, 12–99). Biochemical recurrence was defined as the first value ≥0.2 ng/ml.

Results

At two years, the proportion of patients free from biochemical recurrence was 80% in patients who received adjuvant radiation therapy versus 54% for those not given radiation therapy (P = 0.036). Actuarial biochemical recurrence at 5 years was 59% vs 41% for the radiation therapy and no radiation therapy groups, respectively. On univariate Cox regression model, the hazard of biochemical failure was also associated with a detectable (≥0.2 ng/ml) postsurgical prostate-specific antigen (P = 0.02) prior to radiation therapy. Pathological T stage (pT3b vs pT4), Gleason score, primary Gleason pattern and positive surgical margins were not significantly associated with biochemical recurrence. The hazard of biochemical failure was around 85% lower in the radiation therapy group than in the observation group (P = 0.002).

Conclusions

Data from the present series suggest that adjuvant radiation therapy for patients with seminal vesicle invasion and undetectable (≤0.2 ng/ml) postoperative prostate-specific antigen significantly reduces the likelihood of biochemical failure.

Survival analysis of patients with biochemical relapse after radical prostatectomy treated with androgen deprivation: Castration-resistance influential factors

INTRODUCTION

We evaluate the prognosis of patients with biochemical recurrence (BCR) treated with androgen deprivation therapy (ADT) and to determine the influential factors to castration resistance (CR) and death.

METHODS

From a series of 1310 patients with T1-T2 prostate cancer treated with radical prostatectomy between 1989 and 2012, 371 had BCR. Patients with lymph node involvement were excluded. We analyzed only the 159 treated with salvage ADT. At the end of the study, 77 (48%) had developed CR.

RESULTS

The median follow-up to CR was 9.2 years. The CR-resistant free survival (RFS) was 76 ± 3%, 62 ± 3% and 43 ± 9% in 5, 10 and 15 years, respectively. The RFS median time was 14 years. In the multivariate study, the prostate-specific antigen (PSA) doubling time (PSA-DT) was <6 months (p = 0.01) (hazard ratio [HR] 3; 95% confidence interval [CI] 1.4-6.8, p = 0.007); seminal vesicle involvement (HR 3.1; 95% CI 1.5-6.2, p = 0.01) and PSA velocity in ng/mL/year (HR 1.3; 95% CI 1.1-1.5, p = 0.002) with better cut-off points of 0.84 ng/mL/year (p = 0.04) (HR 4; 95% CI 1.7-9.4, p = 0.001) were influential variables. Specific survival (SS) at 5, 10 and 15 years since surgery was 96 ± 1, 85 ± 2 and 76 ± 4, respectively. The time of CR to death was 30 ± 6% at 5 years, with the median at 3.2 years. In the multivariate only Ki 67 (HR 1.04; 95% CI 1.005-1.08, p = 0.02) had an independent influence.

CONCLUSIONS

In BCR patients treated with ADT, the median to CR was 14 years. PSA-DT <6 months, PSA velocity (ng/mL/year) and seminal vesicle involvement were influential variables. From the CR, the median time to death was 3.2 years. Ki-67 marker was an independent influence.

Gold seed fiducials in analysis of linear and rotational displacement of the prostate bed

BACKGROUND AND PURPOSE

This study aimed to investigate the magnitude of interfraction prostate bed motion during radiotherapy using both the implanted gold seed fiducials and the soft tissue registration and to define reasonable planning target volume (PTV) margins for different localization methods.

MATERIAL AND METHODS

Thirteen prostatectomized prostate cancer patients, after implanting four gold seed fiducials into their prostate bed, were imaged daily using a pretreatment cone-beam computed tomography (CBCT). Linear and the rotational prostate bed motion (PBM) was measured for 466 CBCTs.

RESULTS

The linear PBM mean and standard deviation values in millimeters are 0.0 ± 0.5, 0.7 ± 2.1 and 0.8 ± 1.6 in the LR, SI and AP axes, respectively. In 20% of the fractions the rotation of the prostate bed in sagittal plane exceeds ±6° and in 5% it exceeds ±10° from the position on the planning CT. In the transversal and coronal planes 1% and 2% of it exceeds ±6°. The PTV margins are 2.4, 6.5 and 6.6mm in the LR, SI and AP axes, respectively, if imaging is performed for the first three treatment fractions.

CONCLUSION

The linear PBM is largest in the SI and AP axis, whereas the rotation is largest in the sagittal plane. Bone localization during the first three treatment fractions can reduce PTV margins by 52%, 18% and 10% in the LR, SI and AP axes, respectively, whereas in daily CBCT the use of the gold seed fiducials seems profitable.

Multimodality therapy for patients with high-risk prostate cancer: current status and future directions

Prostate cancer is the most commonly diagnosed cancer and second most common cause of cancer death in American men. Although high-risk disease accounts for less than 15% of diagnoses, high-risk prostate cancer patients have a cancer-specific mortality rate of 15% at 10 years. There is currently no consensus on the optimal management of high-risk disease because (1) there are different primary modalities available (ie, surgery, radiation), for which there are no randomized trials comparing efficacy; and (2) unstandardized timing of different therapies (ie, neoadjuvant v concurrent v adjuvant), which makes comparisons of efficacy problematic. Increased understanding into the mechanisms leading to the formation of advanced metastatic disease has spurred the development of agents to target these pathways. However, new questions regarding optimal management of disease arise with regard to the role of these therapies in combination with "conventional" primary modalities for earlier stage, high-risk prostate cancer patients. In this article, we review the transforming world of multimodality therapy in high-risk prostate cancer.

Treatment-related toxicity and symptom-related bother following postoperative radiotherapy for prostate cancer

INTRODUCTION

Patients have reported late effects and symptom-related bother following postoperative radiotherapy for prostate cancer.

METHODS

Patients treated with postoperative radiotherapy were surveyed at a median 56 months after radiotherapy using the Prostate Cancer Radiation Therapy instrument. A retrospective review was undertaken to obtain Radiation Therapy Oncology Group-Late Effects Normal Tissue (RTOG-LENT) toxicity scores at baseline and during follow-up.

RESULTS

Survey response was 64.5%. Median prostate bed radiation dose was 66 Gy given at a median 14 months after surgery. Adjuvant hormone therapy was given for 2 to 3 years to 40 patients; 22 received salvage therapy. PCRT impairment subscales were reported as mild for gastrointestinal dysfunction, moderate for genitourinary dysfunction and marked for sexual dysfunction. The use of one or more incontinence pads daily was reported by 25.6% and was similar to 23% use reported at baseline. Frequent or worse urinary frequency or hematuria was reported by 4.8%, and by 8.4% of respondents for bowel dysfunction. Moderate to severe disruption from bowel and bladder dysfunction was reported by up to 5.4% and 2.4% of respondents, respectively. Erectile function was described as poor to none in 88.3% of respondents, and dissatisfaction with sexual functioning was reported by 42.7%. Counselling or treatment was offered to 59% of those followed.

CONCLUSION

Combined surgery and postoperative radiotherapy are associated with low and moderate rates of bowel and bladder dysfunction respectively, with low reported bother. High levels of sexual dysfunction and bother are seen following combined therapy. More effective pre- and post-treatment counselling are required, along with research into more effective prevention and treatment strategies.

Salvage radiotherapy following biochemical relapse after radical prostatectomy: proceedings of the Genito-Urinary Radiation Oncologists of Canada consensus meeting

For patients with recurrent prostate cancer after radical prostatectomy, salvage radiotherapy is the only potentially curative treatment option. However, until recently there has been a paucity of data on the effectiveness of this approach. In light of recently published studies, the Genito-Urinary Radiation Oncologists of Canada (GUROC) met and crafted a consensus statement regarding the current place of salvage radiotherapy. GUROC also identified gaps in current knowledge and identified ongoing study protocols that will advance our knowledge in this area.This report summarizes the main conclusions of the meeting and the commentary provided during the consensus-building process, and outlines the consensus statement that was subsequently adopted.

Lymphotropic nanoparticle-enhanced magnetic resonance imaging (LNMRI) identifies occult lymph node metastases in prostate cancer patients prior to salvage radiation therapy

Twenty-six patients with prostate cancer status post-radical prostatectomy who were candidates for salvage radiation therapy (SRT) underwent lymphotropic nanoparticle enhanced MRI (LNMRI) using superparamagnetic nanoparticle ferumoxtran-10. LNMRI was well tolerated, with only two adverse events, both Grade 2. Six (23%) of the 26 patients, previously believed to be node negative, tested lymph node positive by LNMRI. A total of nine positive lymph nodes were identified in these six patients, none of which were enlarged based on size criteria.

Early salvage radiotherapy for patients with PSA relapse after radical prostatectomy

PURPOSE

To assess the effectiveness of early salvage radiotherapy (RT) for patients with prostate-specific antigen (PSA) relapse after radical prostatectomy (RP) retrospectively.

METHODS

Fifty-one patients underwent salvage RT for biochemical relapse of prostate cancer initially treated with RP. All patients had persistent or rising PSA >0.20 ng/ml at some point after surgery, or three successive PSA elevations after a postoperative nadir if PSA was < or =0.20 ng/ml. Most (96%) of pre-RT PSA were less or equal to 0.50 ng/ml, and median value was 0.25 ng/ml (range, 0.05-0.90 ng/ml). Median RT dose was 60 Gy (range, 50-66 Gy). Multivariate Cox regression analysis was performed for PSA before RP and salvage RT, margin status, seminal vesicle involvement, extracapsular invasion, Gleason score, PSA doubling time (PSADT), and RT dose to identify significant predictors of biochemical outcome.

RESULTS

Median follow-up was 36 months. The 3-year biochemical no evidence of disease rate (bNED) was 55.1%. On multivariate analysis only the following factors were significantly associated with improved bNED: PSADT >3.0 months (P = 0.008), Gleason score < or =7 (P = 0.01), and RT dose > or =60 Gy (P = 0.028).

CONCLUSIONS

Although a total dose of 60 Gy was effective at a low pre-RT PSA levels with short follow-up, an RT dose > or =60 Gy resulted in superior biochemical outcomes even in patients with a pre-RT PSA < or =0.50 ng/ml.

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

PURPOSE

To evaluate the outcome of postoperative radiotherapy (PORT) and salvage RT (SART) using a three-dimensional conformal two-dynamic arc (3D-ART) or 3D six-field technique in 431 prostate cancer patients.

METHODS AND MATERIALS

Of the 431 patients, 258 underwent PORT (started <6 months after radical prostatectomy) and 173 underwent SART because of biochemical failure after radical prostatectomy. The median patient age, preoperative prostate-specific antigen level, and Gleason score was 66 years, 9.4 ng/mL, and 7, respectively. The median radiation dose was 70 Gy in 35 fractions for both PORT and SART. The 3D six-field and 3D-ART techniques were used in 25.1% and 74.9% of patients, respectively. Biochemical failure was defined as a post-RT prostate-specific antigen nadir plus 0.1 ng/mL.

RESULTS

Acute toxicity included rectal events (PORT, 44.2% and 0.8% Grade 1-2 and Grade 3, respectively; SART, 42.2% and 1.2% Grade 1-2 and Grade 3, respectively) and urinary events (PORT, 51.2% and 2.3% Grade 1-2 and Grade 3-4, respectively; SART, 37.6% and 0% Grade 1-2 and Grade 3, respectively). Late toxicity also included rectal events (PORT, 14.7% and 0.8% Grade 1-2 and Grade 3-4, respectively; SART, 15.0% and 0.6% Grade 1-2 and Grade 3, respectively) and urinary events (PORT, 28.3% and 3.7% Grade 1-2 and Grade 3-4, respectively; SART, 19.3% and 0.6% Grade 1-2 and Grade 3, respectively). After a median follow-up of 48 months, failure-free survival, including biochemical and clinical failure, was significantly longer in the PORT patients (79.8% vs. 60.5%, p < 0.0001). Multivariate analysis showed that a prostate-specific antigen level postoperatively but before RT of >/=0.2 ng/mL (p < 0.001), Gleason score >6 (p = 0.025) and use of preoperative androgen deprivation (p = 0.002) correlated significantly with shorter failure-free survival. Multivariate analysis showed that PORT and the 3D-ART technique correlated with greater late urinary toxicity.

CONCLUSION

PORT and early referral for SART offer better disease control after radical prostatectomy. The greater urinary toxicity occurring after PORT and 3D-ART requires further investigation to improve the therapeutic index.

Radiotherapy after radical prostatectomy for adenocarcinoma of the prostate: a UK institutional experience and review of published studies

AIMS

The role of radiotherapy to the prostate bed after radical prostatectomy is the subject of much debate. We carried out a retrospective analysis of all patients treated with either adjuvant radiotherapy (ART) or salvage radiotherapy (SRT) in a single UK cancer centre and compared outcomes with published studies.

MATERIALS AND METHODS

All patients receiving radiotherapy at any time after a radical prostatectomy were identified and data collected. Patients were referred for ART because of positive surgical margins. SRT was carried out in patients with a detectable or rising prostate-specific antigen (PSA) postoperatively. Patients received either 55 Gy in 20 fractions or 60-64 Gy in 30-32 fractions. All but eight patients were treated using three-dimensional conformal radiotherapy. Both groups were combined for statistical analysis. Biochemical progression-free survival (BPFS) was calculated and displayed using Kaplan-Meier curves. Cox regression was used for univariate and multivariate analysis.

RESULTS

In total, 40 patients received postoperative radiotherapy and had a 3-year overall BPFS of 64%. There was no significant difference in 3-year BPFS between ART and SRT (73% vs 61%, P=0.33). Univariate analysis showed that 3-year BPFS was significantly longer if the highest postoperative PSA was<0.5 ng/ml compared with> or =0.5 ng/ml (83% vs 47%, P=0.019), and if the Gleason grade was <7 compared with > or =7 (92% vs 49%, P=0.007). A PSA at diagnosis<10 ng/ml, positive surgical margins, absence of seminal vesicle involvement and neoadjuvant hormones were all associated with a trend towards improved BPFS. Patients with all of these factors had a 3-year BPFS of 91%. Multivariate analysis of the same parameters showed that only Gleason grade remained statistically significant (P=0.019).

CONCLUSIONS

The results from this series are in line with published studies, and support the evidence that prostate bed radiotherapy may affect biochemical control in a proportion of patients at risk of relapse. It is not clear whether ART in patients at high risk of relapse or SRT on relapse is most effective.

Health-related quality of life after adjuvant and salvage postoperative radiotherapy for prostate cancer - a prospective analysis

BACKGROUND AND PURPOSE

The aim of the study was to analyze health-related quality of life changes after postoperative radiotherapy (RT) for prostate cancer.

MATERIALS AND METHODS

A group of 101 patients has been surveyed prospectively before (time A), at the last day (B), two months after (C) and >1 year after (D) RT using a validated questionnaire (Expanded Prostate Cancer Index Composite) with urinary, bowel, sexual and hormonal domains. The prostatic fossa was treated with a four-field box technique up to a total dose of 66.6 Gy.

RESULTS

While median urinary scores reached baseline levels already two months after radiotherapy (function/bother scores at time A-B-C-D: 94/89-89/75-94/89-94/89; A vs. B: p<0.01), bowel problems needed a longer time to recover (function/bother scores at time A-B-C-D: 96/100-85/89-88/93-96/100; A vs. B/C: p<0.01). Greater bladder volumes inside specific isodoses were associated with temporary significantly lower urinary bother scores and chronically lower urinary incontinence scores. Only 7% of patients reported of erections firm enough for intercourse before RT, so that RT-associated sexual toxicity played a minor role.

CONCLUSIONS

In contrast to bowel symptoms, acute urinary problems recover very soon after the end of postoperative RT. After >1 year, only minor HRQOL changes occurred in comparison to baseline scores.

Evidence-based radiation oncology: Definitive, adjuvant and salvage radiotherapy for non-metastatic prostate cancer

The standard treatment options based on the risk category (stage, Gleason score, PSA) for localized prostate cancer include surgery, radiotherapy and watchful waiting. The literature does not provide clear-cut evidence for the superiority of surgery over radiotherapy, whereas both approaches differ in their side effects. The definitive external beam irradiation is frequently employed in stage T1b-T1c, T2 and T3 tumors. There is a pretty strong evidence that intermediate- and high-risk patients benefit from dose escalation. The latter requires reduction of the irradiated normal tissue (using 3-dimensional conformal approach, intensity modulated radiotherapy, image-guided radiotherapy, etc.). Recent data suggest that prostate cancer may benefit from hypofractionation due to relatively low alpha/beta ratio; these findings warrant confirmation though. The role of whole pelvis irradiation is still controversial. Numerous randomized trials demonstrated a clinical benefit in terms of biochemical control, local and distant control, and overall survival from the addition of androgen suppression to external beam radiotherapy in intermediate- and high-risk patients. These studies typically included locally advanced (T3-T4) and poor-prognosis (Gleason score >7 and/or PSA >20 ng/mL) tumors and employed neoadjuvant/concomitant/adjuvant androgen suppression rather than only adjuvant setting. The ongoing trials will hopefully further define the role of endocrine treatment in more favorable risk patients and in the setting of the dose escalated radiotherapy. Brachytherapy (BRT) with permanent implants may be offered to low-risk patients (cT1-T2a, Gleason score <7, or 3+4, PSA <or=10 ng/mL), with prostate volume of <or=50 ml, no previous transurethral prostate resection and a good urinary function. Some recent data suggest a benefit from combining external beam irradiation and BRT for intermediate-risk patients. EBRT after radical prostatectomy improves disease-free survival and biochemical and local control rates in patients with positive surgical margins or pT3 tumors. Salvage radiotherapy may be considered at the time of biochemical failure in previously non-irradiated patients.

Long-term results and predictive factors of three-dimensional conformal salvage radiotherapy for biochemical relapse after prostatectomy

PURPOSE

Salvage radiotherapy (RT) is used to treat patients with biochemical failure after radical prostatectomy (RP). Although retrospective series have demonstrated that salvage RT will result in biochemical response in approximately 75% of patients, long-term response is much lower (20-40%). The purpose of this study was to determine prognostic factors related to the prostate-specific antigen (PSA) outcome after salvage RT.

METHODS AND MATERIALS

Between 1991 and 2004, 171 patients received salvage RT at the University of Heidelberg. Patient age, margin status, Gleason score, tumor grading, pathologic tumor stage, pre-RP and pre-RT PSA levels, and time from RP to rise of PSA were analyzed.

RESULTS

Median follow-up time was 39 months. The 5-year overall and clinical relapse-free survival were 93.8% and 80.8%, respectively. After RT serum PSA decreased in 141 patients (82.5%). The 5-year biochemical relapse-free survival was 35.1%. Univariate analysis showed following statistically significant predictors of PSA recurrence after RT: preoperative PSA level (p = 0.035), pathologic tumor classification (p = 0.001), Gleason score (p < 0.001), tumor grading (p = 0.004), and pre-RT PSA level (p = 0.031). On multivariate analysis, only Gleason score (p = 0.047) and pre-RT PSA level (p = 0.049) were found to be independently predictive of PSA recurrence.

CONCLUSIONS

This study represents one of the largest retrospective studies analyzing the outcome of patients treated with salvage RT at a single institution. Our findings suggest that patients with Gleason score <7 and low pre-RT PSA levels are the best candidates for salvage RT, whereas patients with high-grade lesions should be considered for additional treatment (e.g., hormonal therapy).

Influence of the initial rectal distension on posterior margins in primary and postoperative radiotherapy for prostate cancer

BACKGROUND AND PURPOSE

The aim of the study was to define the effect of different rectum fillings in the planning CT study on the posterior clinical target volume (CTV) displacements (PD) in primary and postoperative radiotherapy (RT) for prostate cancer.

MATERIALS AND METHODS

Fifty patients underwent CT scans in supine position with a full bladder and an empty bladder before RT and at several points in time during the treatment. PD were determined depending on the initial rectum volume (RV), average cross-sectional rectal area (CSA), and the rectal diameter at the level of the bladder neck (RD).

RESULTS

Posterior CTV motion was not found to be minimal with a particularly small initial rectum filling. Steeply increasing PD resulted for patients with RV>120cm(3), CSA>12cm(2), and RD>4.5cm. While below these critical values a posterior margin of 6mm/9mm allowed to cover 80%/90% of displacements, 18mm/24mm were needed for patients with larger rectum fillings. No correlation of increasing rectum distension with increasing PD was found at the apex level. PD could not be reduced by voiding the bladder.

CONCLUSIONS

Defining the posterior margin in prostate RT, the initial rectum distension and the superior-inferior CTV level has to be considered. Patients with large initial rectum fillings have preferentially the need for repeated planning CT scans or image-guided RT.

Radiothérapie pelvienne pour récidive biochimique isolée après prostatectomie pour cancer de prostate : quels volumes ?

After prostatectomy, radiotherapy is a potential curable treatment. From the surgery series, it is possible to identify all the localization at risk in case of biochemical relapse after prostatectomy. The target volume of irradiation has to be defined according to the pathological findings. The CTV is limited to the pelvic fascia laterally, to the anterior wall of the rectum behind. The inferior limit includes the anastomosis, and the superior is easier to define with the length of the prostatic gland. The inclusion of area of seminal vesicles and pelvic node areas should be discussed. The use of surgical clips on the anastomosis and image fusionning techniques including the preoperative imaging would help physicians to define the CTV's limits.

Cancer of the prostate

Prostate carcinoma, with about 190,000 new cases occurring each year (15% of all cancers in men), is the most frequent cancer among men in northern and western Europe. Causes of the disease are essentially unknown, although hormonal factors are involved, and diet may exert an indirect influence; some genes, potentially involved in hereditary prostate cancer (HPC) have been identified. A suspect of prostate cancer may derive from elevated serum prostate-specific antigen (PSA) values and/or a suspicious digital rectal examination (DRE) finding. For a definitive diagnosis, however, a positive prostate biopsy is requested. Treatment strategy is defined according to initial PSA stage, and grade of the disease and age and general conditions of the patient. In localized disease, watchful waiting is indicated as primary option in patients with well or moderately differentiated tumours and a life expectancy <10 years, while radical prostatectomy and radiotherapy (with or without hormone-therapy) could be appropriate choices in the remaining cases. Hormone-therapy is the treatment of choice, combined with radiotherapy, for locally advanced or bulky disease and is effective, but not curative, in 80-85% of the cases of advanced disease. Patients who develop a hormone-refractory prostate cancer disease (HRPC) have to be evaluated for chemotherapy because of the recent demonstration of improved overall survival (2-2.5 months) and quality of life with docetaxel in more than 1,600 cases.

Outcome of salvage radiotherapy for biochemical failure after radical prostatectomy with or without hormonal therapy

BACKGROUND

This study analyzed the outcome of salvage radiotherapy for biochemical failure after radical prostatectomy (RP). By comparing the outcomes for patients who received RT alone and for those who received combined RT and hormonal therapy, we assessed the potential benefits of hormonal therapy.

PATIENTS AND METHODS

This cohort was comprised of 101 patients who received salvage RT between 1990 and 2001 for biochemical failure after RP. Fifty-nine of these patients also received hormone. Margin status (positive vs. negative), extracapsular extension (yes vs. no), seminal vesicle involvement (yes vs. no), pathologic stage, Gleason score, pre-RP PSA, post-RP PSA, pre-RT PSA, hormonal use, radiotherapy dose and technique, RP at M. D. Anderson Cancer Center, and time from RP to salvage RT were analyzed. Statistically significant variables were used to construct prognostic groups.

RESULTS

Independent prognostic factors for the RT-alone group were margin status and pre-RT PSA. RP at M. D. Anderson Cancer Center was marginally significant (p = 0.06) in multivariate analysis. Pre-RT PSA was the only significant prognostic factor for the combined-therapy group. We used a combination of margin status and pre-RT PSA to construct a prognostic model for response to the salvage treatment based on the RT group. We identified the favorable group as those patients with positive margin and pre-RT PSA < or = 0.5 ng/mL vs. the unfavorable group as otherwise. This stratification separates patients into clinically meaningful groups. The 5-year PSA control probabilities for the favorable vs. the unfavorable group were 83.7% vs. 61.7% with radiotherapy alone (p = 0.03). Androgen ablation seemed to be most beneficial in the unfavorable group.

CONCLUSION

After prostatectomy, favorable-group patients may fare well with salvage radiotherapy alone. These patients may be spared the toxicity of androgen ablation. The other patients may benefit most from a combined approach with hormonal treatment. We further suggest that salvage radiotherapy should be given early when the PSA is still low.

[Delays and treatment interruptions: difficulties in administering radiotherapy in an ideal time-period]

Prescribed total radiation dose should be administered within in a specific time-frame and delays in commencing treatment and/or unplanned interruptions in radiation delivery are unacceptable because, in certain cancer sites, treatment-time prolongation can have a deleterious effect on local tumour control, and on patient outcomes. The present review evaluated the causes of initial treatment delays as well as interruptions in the scheduled radiotherapy. The literature search highlighted a significant concern in avoiding treatment-time prolongation in head and neck, cervix, breast and lung cancer. Among the causes involved in delay in radiotherapy commencement factors such as waiting lists, lack of material and human resources, and an increase complexity in planning, simulation and verification are highlighted. Most authors recommend radiotherapy commencement as soon as possible in radical (exclusive irradiation with active tumour present) and palliative situations with a maximum delay of no more than 6 to 8 weeks in the case of adjuvant radiotherapy (post-resection) programs. Interruptions during the course of treatment include: planned unit maintenance and servicing, acute patient toxicity or unexpected malfunction of linear accelerators; this last feature has the most deleterious effect on patients as well as radiotherapy practitioners. Interruptions that impact on the programmed time-course for radiotherapy needs to be compensated-for so as assure the biological equivalence in treatment efficacy with respect to cancer site and stage.

Current Opinion on Adjuvant and Salvage Treatment after Radical Prostatectomy

AIMS

The role of postoperative radiotherapy and hormone treatment after radical prostatectomy is uncertain, with no good evidence base to guide practice. In particular, it is not known whether a blanket policy of adjuvant therapy offers any advantage over a selective approach using salvage treatment in people who develop biochemical failure. Furthermore the technique for postoperative radiotherapy to the prostate bed has not been well described. We surveyed the opinion of UK clinical oncologists to describe current practice, with a view to informing the design of clinical trials in this setting.

MATERIALS AND METHODS

A questionnaire was designed to elicit the opinion and clinical practice of UK clinical oncologists on the use of radiotherapy and hormone therapy after radical prostatectomy. The questionnaire was distributed to the delegates at the British Institute of Radiology Conference 'Contemporary issues in Prostate Cancer Radiotherapy' on 9 May 2003.

RESULTS

Forty-nine out of 70 (70%) clinical oncologists completed the questionnaire. With an undetectable postoperative prostate-specific antigen (PSA) less than 0.04 ng/ml, opinion was divided on the role of adjuvant therapy. For example, adjuvant radiotherapy was recommended by 51% (25/49) of respondents for cases with pT3 margin positive disease. When recommending adjuvant radiotherapy, 60% (59/99) recommended hormone therapy in addition. In cases with an asymptomatic rising PSA after radical prostatectomy who had not received adjuvant therapy, 93% (43/46) recommended salvage radiotherapy, but the PSA threshold for recommending such treatment varied widely. The two most common dose-fractionation regimens for salvage radiotherapy to the prostate bed were 62-64 Gy in 2 Gy daily fractions (47%), and 50-55 Gy in 20 fractions (30%).

CONCLUSIONS

Opinion is varied within the UK on the role of radiotherapy and hormone therapy after radical prostatectomy. The results of this survey should inform the design of future clinical trials.

Impact of Volume Weighted Mean Nuclear Volume on Outcomes Following Salvage Radiation Therapy After Radical Prostatectomy

PURPOSE

Although salvage radiation therapy (RT) is a potentially curative treatment option for men with biochemical failure after radical prostatectomy (RP), to our knowledge there are no definitive pretreatment factors predicting patients likely to benefit from this treatment. We examined the impact of volume weighted mean nuclear volume (MNV) of biopsy specimens on disease outcomes and describe its usefulness as a new independent predictor.

MATERIALS AND METHODS

We analyzed 33 patients who received salvage RT for biochemical failure after RP, including 11 who had received neoadjuvant hormone therapy before RP. Salvage RT was delivered to the prostatic bed at a total dose of 60 Gy with a 4-field contoured technique. Unbiased estimates of MNV were calculated from more than 100 cancer nuclei per patient captured from biopsy specimens based on a stereological method and compared with other clinical and pathological findings, including patient age, pretreatment prostate specific antigen (PSA), PSA density, biopsy Gleason score, neoadjuvant therapy, surgical Gleason score, pathological stage, tumor volume, surgical margin status, biochemical disease-free duration before RT, nadir PSA and PSA doubling time before RT, and pre-RT PSA with regard to predicting the disease outcome after salvage RT.

RESULTS

The median followup after salvage RT was 43.4 months. A total of 17 patients (52%) experienced biochemical failure a median of 6.7 months (range 0 to 48.1) after RT. On univariate analysis MNV and log(pre-RT PSA) were significant predictors of disease outcome in all patients and in the 22 nonneoadjuvant patient subset (p = 0.0124 and 0.0159, respectively). Log(nadir PSA) and PSA doubling time were also significant in the latter subset (p = 0.0287 and 0.0475, respectively). However, dual multivariate analysis revealed that MNV was the only independent predictor in the 2 groups (logistic regression analysis p = 0.00931 and 0.03511, and Cox proportional hazards analysis p = 0.00483 and 0.02277, respectively). There was a statistically significant biochemical disease-free survival advantage for small vs large MNV in each data set (p = 0.0072 and 0.0036, respectively).

CONCLUSIONS

Our results suggest that an estimate of MNV contributes significantly to the prediction of biochemical control after salvage RT. However, further investigation in a larger nonneoadjuvant population is needed to confirm its significance in combination with other clinical and pathological findings.

Salvage radiotherapy in the treatment of prostate cancer

For patients undergoing radical prostatectomy for prostate adenocarcinoma, the most common cause of failure is an asymptomatic increase in levels of prostate-specific antigen (PSA). Salvage radiotherapy (RT) to the prostate bed has been used when there is no clinical evidence of metastatic disease. However, this is still not widely accepted because there is currently no consensus on the optimal management of an isolated PSA failure. Salvage RT given in a select group of patients is effective, with a 70% to 80% biochemical response rate and a long-term biochemical control rate as high as 35% to 40%. These data indicate that RT offers a substantial risk of curative salvage of patients who fail radical prostatectomy. Although there is interest in studying investigational modalities (eg, vaccine therapy) among patients with asymptomatic, PSA-detected recurrences after surgery, caution must be applied, and treatment modalities with known curative potential (ie, RT) should be used before noncurative techniques are attempted. This article outlines the rationale, results, and toxicity of salvage RT for an asymptomatic increase in PSA levels, with emphasis on identifying patients with favorable prognostic factors with higher rates of long-term biochemical control with local treatment.

Prostate cancer: radical prostatectomy

Today, more men than ever before are being followed after radical prostatectomy. Prognosis and follow-up should be based on the pathologic specimen. Measurable prostate-specific antigen (PSA) after surgery defines failure, with time to detectable PSA and rate of PSA rise being useful prognostic factors. The natural history of untreated biochemical failure is protracted, a fact to be considered in discussions of adjuvant treatment. Early in disease recurrence, imaging studies to locate residual disease rarely are useful clinically. Both adjuvant and salvage radiation to the prostate bed have benefits and risks, but neither is superior in overall prostate cancer survival. The timing of hormone therapy remains largely empiric. The promise of effective cytotoxic chemotherapy still is greater than its actual benefits, although novel cytostatic agents are being developed. The future management of this disease will improve with better molecular definition of risk and therapeutic response.

Contemporary management of prostate cancer: a practice survey of Ontario genitourinary radiation oncologists

OBJECTIVE

To survey radiation oncology practice in the utilization of hormonal and radiation therapy in the primary, adjuvant and salvage treatment of localized prostate cancer.

MATERIALS AND METHODS

Genitourinary radiation oncologists practicing in Ontario were invited to participate in a practice survey examining staging, hormonal and radiation management, and radiation technique for a variety of common clinical scenarios. Background demographic information was collected on all respondents. The survey consisted of three cases relating to the hormonal/radiation management of low-, intermediate-, and high-risk prostate cancer as well as two adjuvant and one salvage post-prostatectomy scenarios. The survey response rate was 70% (26/37).

RESULTS

Clinicians were more likely to utilize laboratory and imaging studies for staging as the risk categorization increased. Low-risk disease was managed with radiation alone in 26/26 (70 Gy in 65%, 74-79.8 Gy in 35%). Intermediate-risk disease was managed with radiation (70 Gy in 46%, 74-79.8 Gy in 54%) with neoadjuvant hormones in 58%. All respondents managed high-risk disease with adjuvant hormones in addition to radiation therapy (70-71 Gy in 85%, and 76 Gy in 15%). In the pT3a, margin negative (PSA undetectable) scenario, most individuals would not recommend adjuvant radiation (73%). If margins were positive, 30% would still not recommend adjuvant radiation. In the salvage scenario (slowly rising PSA 4 years post-prostatectomy for pT2a close margin disease), all respondents would manage with radiation therapy. Hormones were not routinely recommended in the initial management of the adjuvant and salvage scenarios. Radiation doses utilized for both adjuvant and salvage treatment ranged from 60-70 Gy (median 66 Gy).

CONCLUSIONS

General agreement exists for the management of low- and high-risk disease and in the post-prostatectomy salvage setting. Use of dose-escalation and neoadjuvant hormones in the intermediate-risk setting and use of post-prostatectomy adjuvant radiation in the pT3a scenarios varied among radiation oncologists. Current clinical practice in localized prostate cancer reflects the evolving information in the published medical literature.

Radical radiotherapy for prostate cancer

External beam radiotherapy is one of the curative treatment options for localised prostate cancer. This article will describe recent advances in prostate radiotherapy, focussing on the results of randomised trials which have addressed the role of radiation dose escalation and of adjuvant hormone therapy. Current controversies will then be considered, including the merits of radiotherapy in comparison with alternative approaches to early prostate cancer, and the possible role of adjuvant radiation following surgery. Finally, future developments will be described, including hypofractionation and dose individualisation, which have the potential to further improve the outcome of external beam radiotherapy for prostate cancer.

Selecting a secondary treatment

There is compelling evidence that early hormonal therapy prolongs life in many stages of prostate cancer. Large-scale trials to answer this question have not yet been conducted in surgically treated patients or in patients with PSA-only relapse. Thus, many physicians and patients use early hormone therapy in PSA-only relapse. Many unique new agents are being tested in this population and may offer benefits. Patients and physicians are encouraged to participate in such trials, with hormone therapy reserved for subsequent use. Following failure of primary hormone therapy, a standard algorithm of care exists: antiandrogen withdrawal, use of alternative or first-line anti-androgens. ketoconazole. and chemotherapy. At each interval, clinical trials should be offered since none of these maneuvers are proven to prolong life.

Indium-111-capromab pendetide radioimmunoscintigraphy and prognosis for durable biochemical response to salvage radiation therapy in men after failed prostatectomy

PURPOSE

We evaluated the prognostic significance of indium-111 (111In)-capromab pendetide imaging for patients with prostate cancer who underwent salvage radiotherapy (RT) for recurrent disease after prostatectomy.

PATIENTS AND METHODS

Records were reviewed for all men who underwent 111In-capromab pendetide imaging at a single institution from February 1997 through December 1999. We identified 30 eligible men who were radiographically negative for metastatic disease, who had increasing serum prostate-specific antigen (PSA) after primary radical prostatectomy, and who received salvage RT. Clinical interpretations of indium monoclonal antibody (In-mab) scan results were compared with postsalvage RT PSA response.

RESULTS

Using an American Society of Therapeutic Radiation and Oncology definition of PSA failure, in men with a positive scan in at least one location (n = 14), the cumulative 2-year PSA control after salvage RT was 0.38 +/- 0.13 (+/- SE) compared with 0.31 +/- 0.13 for men with a normal antibody scan in and outside the prostate fossa (n = 15; proportional hazard ratio [PHR] = 1.32; 95% confidence interval [CI], 0.52 to 3.36). For men with a positive antibody scan limited to the prostate fossa (n = 9), PSA control at 2 years was 0.13 +/- 0.12 (PHR 1.77; 95% CI, 0.65 to 4.85). The 2-year probability of PSA control after salvage RT for men with positive scan results outside the prostate bed irrespective of In-mab findings in the prostate fossa (n = 5) was 0.60 +/- 0.22 (PHR 0.81; 95% CI, 0.17 to 3.78).

CONCLUSION

In contrast to previous reports, for patients with postprostatectomy biochemical relapse who received salvage RT, presalvage RT In-mab scan findings outside the prostate fossa were not predictive of biochemical control after RT.

Significant correlation between rectal DVH and late bleeding in patients treated after radical prostatectomy with conformal or conventional radiotherapy (66.6-70.2 Gy)

PURPOSE

Investigating the correlation between dosimetric/clinical parameters and late rectal bleeding in patients treated with adjuvant or salvage radiotherapy after radical prostatectomy.

METHODS AND MATERIALS

Data of 154 consecutive patients, including three-dimensional treatment planning and dose-volume histograms (DVHs) of the rectum (including filling), were retrospectively analyzed. Twenty-six of 154 patients presenting a (full) rectal volume >100 cc were excluded from the analysis. All patients considered for the analysis (n = 128) were treated at a nominal dose equal to 66.6-70.2 Gy (ICRU dose 68-72.5 Gy; median 70 Gy) with conformal (n = 76) or conventional (n = 52) four-field technique (1.8 Gy/fr). Clinical parameters such as diabetes mellitus, acute rectal bleeding, hypertension, age, and hormonal therapy were considered. Late rectal bleeding was scored using a modified Radiation Therapy Oncology Group scale, and patients experiencing >or=Grade 2 were considered bleeders. Median follow-up was 36 months (range 12-72). Mean and median rectal dose were considered, together with rectal volume and the % fraction of rectum receiving more than 50, 55, 60, and 65 Gy (V50, V55, V60, V65, respectively). Median and quartile values of all parameters were taken as cutoff for statistical analysis. Univariate (log-rank) and multivariate (Cox hazard model) analyses were performed.

RESULTS

Fourteen of 128 patients experienced >or=Grade 2 late bleeding (3-year actuarial incidence 10.5%). A significant correlation between a number of cutoff values and late rectal bleeding was found. In particular, a mean dose >or=54 Gy, V50 >or=63%, V55 >or=57%, and V60 >or=50% was highly predictive of late bleeding (p <or= 0.01). A rectal volume <60 cc and type of treatment (conventional vs. conformal) were also significantly predictive of late bleeding (p = 0.05). Concerning clinical variables, acute bleeding (p < 0.001) was significantly related to late bleeding, and a trend was found for hypertension (p = 0.11). After patients were grouped into those with V50 >or=63% and those with V50 <63% (DVH grouping), data were fitted with a Cox regression hazard model using DVH grouping, rectal volume, and the main clinical parameters as independent variables. Results of the analysis showed that DVH grouping (relative risk 3.3; p = 0.04) and acute bleeding (relative risk 7.1; p = 0.001) are independently predictive of late bleeding.

CONCLUSIONS

DVHs of the rectum are significantly correlated with late bleeding for patients irradiated at 66.6-70.2 Gy after radical prostatectomy.

Pre-treatment nomogram for biochemical control after neoadjuvant androgen deprivation and radical radiotherapy for clinically localised prostate cancer

Phase III studies have demonstrated the clinical benefit of adding neo-adjuvant androgen deprivation to radical radiotherapy for clinically localised prostate cancer. We have developed a nomogram to describe the probability of PSA control for patients treated in this way. Five hundred and seventeen men with clinically localised prostate cancer were treated with 3-6 months of neo-adjuvant androgen deprivation and radical radiotherapy (64Gy in 32#) between 1988 and 1998. Median presenting PSA was 20 ng x ml(-1), and 56% of patients had T3/4 disease. Multivariate analysis of pre-treatment factors was performed, and a nomogram developed to describe PSA-failure-free survival probability. At a median follow-up of 44 months, 233 men had developed PSA failure. Presenting PSA, histological grade and clinical T stage were all highly predictive of PSA failure on multivariate analysis. The nomogram score for an individual patient is given by the summation of PSA (<10=0, 10-19=16, 20-49=44, > or =50=100), grade (Gleason 2-4=0, 5-7=44, 8-10=81) and T stage (T1/2=0, T3/4=35). For a nomogram score of 0, 50, 100 and 150 points the 2 year PSA control rate was 93, 87, 75 and 54%, and the 5 year PSA control rate was 82, 67, 44 and 18%. These results are comparable to those using surgery or higher doses of radical radiotherapy alone. The nomogram illustrates the results of multivariate analysis in a visually-striking way, and facilitates comparisons with other treatment methods.