Combination External Beam Radiation and Brachytherapy Boost With Androgen Suppression for Treatment of Intermediate-Risk Prostate Cancer: An Initial Report of CALGB 99809

Initial Quality of Life and Toxicity Analysis of a Randomized Phase 3 Study of Moderately Hypofractionated Radiation Therapy With or Without Androgen Suppression for Intermediate-Risk Adenocarcinoma of the Prostate: PCG GU003

Purpose

Our objective was to report the quality of life (QoL) analysis and toxicity in patients with intermediate-risk prostate cancer treated with or without androgen deprivation therapy (ADT) in Proton Collaborative Group (PCG) GU003.

Methods and Materials

Between 2012 and 2019, patients with intermediate-risk prostate cancer were enrolled. Patients were randomized to receive moderately hypofractionated proton beam therapy (PBT) to 70 Gy relative biologic effectiveness in 28 fractions to the prostate with or without 6 months of ADT. Expanded Prostate Cancer Index Composite, Short-Form 12, and the American Urological Association Symptom Index instruments were given at baseline and 3, 6, 12, 18, and 24 months after PBT. Toxicities were assessed according to Common Terminology Criteria for Adverse Events (version 4).

Results

One hundred ten patients were randomized to PBT either with 6 months of ADT (n = 55) or without ADT (n = 55). The median follow-up was 32.4 months (range, 5.5-84.6). On average, 101 out of 110 (92%) patients filled out baseline QoL and patient-reported outcome surveys. The compliance was 84%, 82%, 64%, and 42% at 3, 6, 12, and 24 months, respectively. Baseline median American Urological Association Symptom Index was comparable between arms (6 [11%] ADT vs 5 [9%] no ADT, P = .359). Acute and late grade 2+ genitourinary and gastrointestinal toxicity were similar between arms. The ADT arm experienced a QoL decline of mean scores in the sexual (-16.1, P < .001) and hormonal (-6.3, P < .001) domains, with the largest time-specific hormonal differences at 3 (-13.8, P < .001) and 6 (-11.2, P < .001) months. The hormonal QoL domain returned to baseline 6 months after therapy. There was a trend to baseline in sexual function 6 months after completion of ADT.

Conclusions

After 6 months of ADT, sexual and hormonal domains returned to baseline 6 months after completion of treatment for men with intermediate-risk prostate cancer.

Evidenced-based clinical practice guideline for prostate cancer (summary: Japanese Urological Association, 2016 edition)

These guidelines cover a wide range of topics from prostate cancer epidemiology to palliative care. Questions arising in daily clinical practice have been extracted and formulated as clinical questions. In the 4 years since the previous edition, there have been major changes - for example, robot-assisted prostatectomy has rapidly come into widespread use, and new hormones and anticancer drugs have been developed for castration-resistant prostate cancer. In response to these developments, the number of fields included in this guideline was increased from 11 in the 2012 edition to 16, and the number of clinical questions was increased from 63 to 70. The number of papers identified in searches of the existing literature increased from 4662 in the first edition, published in 2006, to 10 490 in the 2012 edition. The number of references has reached 29 448 just during this review period, indicating the exponential increase in research on the topic of prostate cancer. Clinical answers have been prepared based on the latest evidence. Recommendation grades for the clinical answers were determined by radiologists, pathologists, and other specialists in addition to urologists in order to reflect the recent advances and diversity of prostate cancer treatment. Here, we present a short English version of the original guideline, and overview its key clinical issues.

Urinary and Rectal Toxicity Profiles After Permanent Iodine-125 Implant Brachytherapy in Japanese Men: Nationwide J-POPS Multi-institutional Prospective Cohort Study

PURPOSE

To assess, in a nationwide multi-institutional cohort study begun in 2005 and in which 6927 subjects were enrolled by 2010, the urinary and rectal toxicity profiles of subjects who enrolled during the first 2 years, and evaluate the toxicity profiles for permanent seed implantation (PI) and a combination therapy with PI and external beam radiation therapy (EBRT).

METHODS AND MATERIALS

Baseline data for 2339 subjects out of 2354 patients were available for the analyses. Toxicities were evaluated using the National Cancer Institute's Common Terminology Criteria for Adverse Events, and the International Prostate Symptom Scores were recorded prospectively until 36 months after radiation therapy.

RESULTS

Grade 2+ acute urinary toxicities developed in 7.36% (172 of 2337) and grade 2+ acute rectal toxicities developed in 1.03% (24 of 2336) of the patients. Grade 2+ late urinary and rectal toxicities developed in 5.75% (133 of 2312) and 1.86% (43 of 2312) of the patients, respectively. A higher incidence of grade 2+ acute urinary toxicity occurred in the PI group than in the EBRT group (8.49% vs 3.66%; P<.01). Acute rectal toxicity outcomes were similar between the treatment groups. The 3-year cumulative incidence rates for grade 2+ late urinary toxicities were 6.04% versus 4.82% for the PI and the EBRT groups, respectively, with no significant differences between the treatment groups. The 3-year cumulative incidence rates for grade 2+ late rectal toxicities were 0.90% versus 5.01% (P<.01) for the PI and the EBRT groups, respectively. The mean of the postimplant International Prostate Symptom Score peaked at 3 months, but it decreased to a range that was within 2 points of the baseline score, which was observed in 1625 subjects (69.47%) at the 1-year follow-up assessment.

CONCLUSIONS

The acute urinary toxicities observed were acceptable given the frequency and retention, and the late rectal toxicities were more favorable than those of other studies.

MRI-based sector analysis enhances prostate palladium-103 brachytherapy quality assurance in a phase II prospective trial of men with intermediate-risk localized prostate cancer

PURPOSE

Palladium-103 ((103)Pd) may be superior to other isotopes in brachytherapy for localized intermediate-risk prostate cancer because of its relatively short half-life, higher initial dose rate, and greater dose heterogeneity within the target volume; these properties also underscore the need for accurate target delineation and postimplant quality assurance. We assessed the use of prostate sector analysis based on MRI for quality assurance after (103)Pd monotherapy.

METHODS AND MATERIALS

Fifty men with intermediate-risk prostate cancer underwent (103)Pd monotherapy in a prospective phase II trial at MD Anderson Cancer Center. Dosimetric analyses on day 30 after the implant were done using both CT and fused CT/MRI scans. Dosimetric variables were assessed for the entire prostate and for each of three or six sectors. Volumes and dosimetric variables were compared with paired t tests.

RESULTS

Postimplant dosimetric variables for the entire prostate were significantly different on CT vs. CT/MRI (p = 0.019 for V100 and p < 0.01 for D90). Prostate volumes were smaller on the CT/MRI scans (p < 0.00001). The base sector contributed the greatest difference, with doses based on CT/MRI lower than those based on CT (p < 0.01 for V100 and D90). To date, these lower base doses have not affected biochemical outcomes for patients with disease in prostate base biopsy samples.

CONCLUSIONS

CT/MRI is more precise than CT for prostate volume delineation and dosimetric quality assessment and thus provides superior heterogeneity control assessment after (103)Pd monotherapy implants.

Neoadjuvant chemoradiation followed by interstitial prostate brachytherapy for synchronous prostate and rectal cancer

PURPOSE

To describe outcomes with the use of neoadjuvant pelvic chemoradiation followed by prostate interstitial brachytherapy for the treatment of synchronous prostate and rectal cancers.

METHODS AND MATERIALS

An Internal Review Board approved retrospective review was undertaken of 4 patients with synchronous prostate and rectal cancer treated between 2006 and 2008. Patients underwent pelvic chemoradiation followed by prostate brachytherapy, then low anterior resection of the rectum with diverting loop ileostomy and adjuvant chemotherapy. Follow-up evaluation included imaging and laboratory analysis of cancer markers in addition to routine interval history and physical examination.

RESULTS

At 38-62 months postdiagnosis (24-53 months post-treatment), 6 of 8 cancers remained without evidence of relapse. One patient had rising carcinoembryonic antigen levels but no clinically evident rectal cancer relapse; another developed bony metastasis of his high-risk prostate cancer. Three patients experienced grade 1-2 treatment-related toxicity; one patient had grade 3 gastrointestinal toxicity from radiation and surgery, which precluded his receiving adjuvant chemotherapy and ileostomy reversal.

CONCLUSIONS

Chemoradiation followed by prostate brachytherapy, surgery, and adjuvant chemotherapy may be utilized to manage patients with synchronous prostate and rectal cancers.

Combination external beam radiation and brachytherapy boost with androgen deprivation for treatment of intermediate-risk prostate cancer: long-term results of CALGB 99809

BACKGROUND

Combined transperineal prostate brachytherapy and external beam radiation therapy (EBRT) is widely used for treatment of prostate cancer. Long-term efficacy and toxicity results of a multicenter phase 2 trial assessing combination of EBRT and transperineal prostate brachytherapy boost with androgen deprivation therapy (ADT) for intermediate-risk prostate cancer are presented.

METHODS

Intermediate-risk patients per Memorial Sloan-Kettering Cancer Center/National Comprehensive Cancer Network criteria received 6 months of ADT, and 45 grays (Gy) EBRT to the prostate and seminal vesicles, followed by transperineal prostate brachytherapy with I125 (100 Gy) or Pd103 (90 Gy). Toxicity was graded using the National Cancer Institute Common Toxicity Criteria version 2 and Radiation Therapy Oncology Group late radiation morbidity scoring systems. Disease-free survival (DFS) was defined as time from enrollment to progression (biochemical, local, distant, or prostate cancer death). In addition to the protocol definition of biochemical failure (3 consecutive prostate-specific antigen rises>1.0 ng/mL after 18 months from treatment start), the 1997 American Society for Therapeutic Radiology and Oncology (ASTRO) consensus and Phoenix definitions were also assessed in defining DFS. The Kaplan-Meier method was used to estimate DFS and overall survival.

RESULTS

Sixty-one of 63 enrolled patients were eligible. Median follow-up was 73 months. Late grade 2 and 3 toxicity, excluding sexual dysfunction, occurred in 20% and 3% of patients. Six-year DFS applying the protocol definition, 1997 ASTRO consensus, and Phoenix definitions was 87.1%, 75.1%, and 84.9%. Six deaths occurred; only 1 was attributed to prostate cancer. Six-year overall survival was 96.1%.

CONCLUSIONS

In a cooperative setting, combination of EBRT and transperineal prostate brachytherapy boost plus ADT resulted in excellent DFS with acceptable late toxicity for patients with intermediate-risk prostate cancer.

A pilot study of intensity modulated radiation therapy with hypofractionated stereotactic body radiation therapy (SBRT) boost in the treatment of intermediate- to high-risk prostate cancer

Clinical data suggest that large radiation fractions are biologically superior to smaller fraction sizes in prostate cancer radiotherapy. The CyberKnife is an appealing delivery system for hypofractionated radiosurgery due to its ability to deliver highly conformal radiation and to track and adjust for prostate motion in real-time. We report our early experience using the CyberKnife to deliver a hypofractionated stereotactic body radiation therapy (SBRT) boost to patients with intermediate- to high-risk prostate cancer. Twenty-four patients were treated with hypofractionated SBRT and supplemental external radiation therapy plus or minus androgen deprivation therapy (ADT). Patients were treated with SBRT to a dose of 19.5 Gy in 3 fractions followed by intensity modulated radiation therapy (IMRT) to a dose of 50.4 Gy in 28 fractions. Quality of life data were collected with American Urological Association (AUA) symptom score and Expanded Prostate Cancer Index Composite (EPIC) questionnaires before and after treatment. PSA responses were monitored; acute urinary and rectal toxicities were assessed using Common Toxicity Criteria (CTC) v3. All 24 patients completed the planned treatment with an average follow-up of 9.3 months. For patients who did not receive ADT, the median pre-treatment PSA was 10.6 ng/ml and decreased in all patients to a median of 1.5 ng/ml by 6 months post-treatment. Acute effects associated with treatment included Grade 2 urinary and gastrointestinal toxicity but no patient experienced acute Grade 3 or greater toxicity. AUA and EPIC scores returned to baseline by six months post-treatment. Hypofractionated SBRT combined with IMRT offers radiobiological benefits of a large fraction boost for dose escalation and is a well tolerated treatment option for men with intermediate- to high-risk prostate cancer. Early results are encouraging with biochemical response and acceptable toxicity. These data provide a basis for the design of a phase II clinical trial.

Phase II trial of combined high-dose-rate brachytherapy and external beam radiotherapy for adenocarcinoma of the prostate: preliminary results of RTOG 0321

PURPOSE

To estimate the rate of late Grade 3 or greater genitourinary (GU) and gastrointestinal (GI) adverse events (AEs) after treatment with external beam radiotherapy and prostate high-dose-rate (HDR) brachytherapy.

METHODS AND MATERIALS

Each participating institution submitted computed tomography-based HDR brachytherapy dosimetry data electronically for credentialing and for each study patient. Patients with locally confined Stage T1c-T3b prostate cancer were eligible for the present study. All patients were treated with 45 Gy in 25 fractions using external beam radiotherapy and one HDR implant delivering 19 Gy in two fractions. All AEs were graded according to the Common Terminology Criteria for Adverse Events, version 3.0. Late GU/GI AEs were defined as those occurring >9 months from the start of the protocol treatment, in patients with ≥18 months of potential follow-up.

RESULTS

A total of 129 patients from 14 institutions were enrolled in the present study. Of the 129 patients, 125 were eligible, and AE data were available for 112 patients at analysis. The pretreatment characteristics of the patients were as follows: Stage T1c-T2c, 91%; Stage T3a-T3b, 9%; prostate-specific antigen level ≤10 ng/mL, 70%; prostate-specific antigen level >10 but ≤20 ng/mL, 30%; and Gleason score 2-6, 10%; Gleason score 7, 72%; and Gleason score 8-10, 18%. At a median follow-up of 29.6 months, three acute and four late Grade 3 GU/GI AEs were reported. The estimated rate of late Grade 3-5 GU and GI AEs at 18 months was 2.56%.

CONCLUSION

This is the first prospective, multi-institutional trial of computed tomography-based HDR brachytherapy and external beam radiotherapy. The technique and doses used in the present study resulted in acceptable levels of AEs.

Combination of IG-IMRT and permanent source prostate brachytherapy in patients with organ-confined prostate cancer: GU and GI toxicity and effect on erectile function

PURPOSE

To assess toxicity outcomes of image-guided intensity-modulated radiation therapy (IG-IMRT) combined with permanent prostate seed implant in a cohort of patients with localized prostate cancer.

METHODS AND MATERIALS

A retrospective analysis was performed on 67 patients with the median pretreatment prostate-specific antigen level of 5.4. The Gleason score was less than 7 in 7 patients, 7 in 52 patients, and greater than 7 in 8 patients. The median followup was 28.2 months (range, 12-89.5 months). Treatment consisted of 45 (n=65) or 50.4 Gy (n=2) at 1.8 Gy/fraction of IG-IMRT to the prostate and seminal vesicles. Eight patients had simultaneous irradiation of pelvic lymph nodes to 45 (n=65) or 50.4 Gy (n=2). After IG-IMRT, patients received transperineal prostate implant boost with either (103)Pd (n=65, the prescribed D(90) of 100 Gy) or (125)I (n=2, D(90) of 110 Gy). Eleven patients received androgen deprivation therapy with radiotherapy.

RESULTS

Toxicity higher than Grade 3 was not observed. The combined incidence of acute and late Grade 3 genitourinary toxicity was 6%. The combined incidence of acute and late Grade 3 gastrointestinal toxicity was 3%. At least one episode of gastrointestinal bleeding on followup, which could be attributed to radiation, was recorded in 14.9% of patients. For patients achieving erections before radiation, the 3-year Kaplan-Meier potency preservation rate was 66.5%.

CONCLUSIONS

The early toxicity of the combination of IG-IMRT and low-dose rate brachytherapy boost in this study was favorable.