Clinical Outcomes of the CHIRP Trial: A Phase II Prospective Randomized Trial of Conventionally Fractionated Versus Moderately Hypofractionated Prostate and Pelvic Nodal Radiation Therapy in Patients With High-Risk Prostate Cancer

Photon vs proton hypofractionation in prostate cancer: A systematic review and meta-analysis

BACKGROUND

High-level evidence on hypofractionated proton therapy (PT) for localized and locally advanced prostate cancer (PCa) patients is currently missing. The aim of this study is to provide a systematic literature review to compare the toxicity and effectiveness of curative radiotherapy with photon therapy (XRT) or PT in PCa.

METHODS

PubMed, Embase, and the Cochrane Library databases were systematically searched up to April 2022. Men with a diagnosis of PCa who underwent curative hypofractionated RT treatment (PT or XRT) were included. Risk of grade (G) ≥ 2 acute and late genitourinary (GU) OR gastrointestinal (GI) toxicity were the primary outcomes of interest. Secondary outcomes were five-year biochemical relapse-free survival (b-RFS), clinical relapse-free, distant metastasis-free, and prostate cancer-specific survival. Heterogeneity between study-specific estimates was assessed using Chi-square statistics and measured with the I2 index (heterogeneity measure across studies).

RESULTS

A total of 230 studies matched inclusion criteria and, due to overlapped populations, 160 were included in the present analysis. Significant lower rates of G ≥ 2 acute GI incidence (2 % vs 7 %) and improved 5-year biochemical relapse-free survival (95 % vs 91 %) were observed in the PT arm compared to XRT. PT benefits in 5-year biochemical relapse-free survival were maintained for the moderate hypofractionated arm (p-value 0.0122) and among patients in intermediate and low-risk classes (p-values < 0.0001 and 0.0368, respectively). No statistically relevant differences were found for the other considered outcomes.

CONCLUSION

The present study supports that PT is safe and effective for localized PCa treatment, however, more data from RCTs are needed to draw solid evidence in this setting and further effort must be made to identify the patient subgroups that could benefit the most from PT.

Randomized Trial of Concomitant Hypofractionated Intensity Modulated Radiation Therapy Boost Versus Conventionally Fractionated Intensity Modulated Radiation Therapy Boost for Localized High-Risk Prostate Cancer (pHART2-RCT)

PURPOSE

The aim of this work is to report on the results of a phase 2 randomized trial of moderately hypofractionated (MH) versus conventionally fractionated (CF) radiation therapy to the prostate with elective nodal irradiation.

METHODS AND MATERIALS

This was a single-center, prospective, phase 2 randomized study. Patients with high-risk disease (cT3, prostate-specific antigen level >20 ng/mL, or Gleason score 8-10) were eligible. Patients were randomized to either MH using a simultaneous integrated boost (68 Gy in 25 fractions to prostate; 48 Gy to pelvis) or CF (46 Gy in 23 fractions with a sequential boost to the prostate of 32 Gy in 16 fractions), with long-term androgen deprivation therapy. The primary endpoint was grade ≥2 acute gastrointestinal (GI) and genitourinary (GU) toxicity (Common Terminology Criteria for Adverse Events version 3.0). Secondary endpoints included late GI and GU toxicity, quality of life, and oncologic outcomes.

RESULTS

One-hundred eighty patients were enrolled; 90 were randomized to and received MH and 90 to CF. The median follow-up was 67.4 months. Seventy-five patients (41.7%) experienced a grade ≥2 acute GI and/or GU toxicity, including 34 (37.8%) in the MH and 41 (45.6%) in the CF arms, respectively (P = .29). Late grade ≥2 GI (P = .07) and GU (P = .25) toxicity was not significantly different between arms; however, late grade ≥3 GI toxicity was worse in the MH group (P = .01). There were no statistically significant quality-of-life differences between the 2 treatments. There were no statistically significant differences observed in cumulative incidence of biochemical failure (P = .71) or distant metastasis (P = .31) and overall survival (P = .46).

CONCLUSIONS

MH to the prostate and pelvis with androgen deprivation therapy for men with high-risk localized prostate cancer was not significantly different than CF with regard to acute toxicity, quality of life, and oncologic efficacy. However, late grade ≥3 GI toxicity was more common in the MH arm.

Hypofractionated radiation therapy combined with androgen deprivation therapy for high-risk localized prostate cancer

INTRODUCTION

This study aimed to analyse the treatment outcomes of moderately hypofractionated radiation therapy (RT) combined with androgen deprivation therapy (ADT) and the prognostic implications of prostate-specific antigen (PSA) kinetics in high-risk localized prostate cancer.

METHODS

The medical records of 140 patients who underwent definitive RT (70 Gy in 28 fractions) combined with ADT were retrospectively reviewed. ADT consists of a gonadotropin-releasing hormone agonist and an anti-androgen. Clinical outcomes included the biochemical failure rate (BFR), clinical failure rate (CFR), overall survival (OS) and prostate cancer-specific survival (PCSS). The BFR and CFR were stratified by the PSA nadir and the time to the PSA nadir, respectively. Acute and late genitourinary and gastrointestinal adverse events were also recorded.

RESULTS

The 5-year BFR, CFR, OS and PCSS rates were 9.8%, 4.5%, 90.2% and 98.7%, respectively. Ninety-five (67.9%) patients achieved a PSA nadir of 0.01 ng/mL. Patients with a PSA nadir >0.01 ng/mL had a significantly higher BFR and CFR (BFR, P = 0.001; CFR, P = 0.027), even after adjusting for other prognostic factors [per 0.1 ng/mL; BFR, hazard ratio (HR) 4.440, P < 0.001; CFR, HR 4.338, P = 0.001]. However, the time to the PSA nadir and pre-RT PSA were not significantly associated with the BFR and CFR. Six patients (4.3%) reported grade 3 late adverse events, mostly haematuria and haematochezia.

CONCLUSION

Definitive RT with moderate hypofractionation combined with long-term ADT showed good efficacy for high-risk localized prostate cancer. The lowest PSA nadir was significantly associated with a low recurrence rate, indicating the importance of PSA follow-up.

Prospective results for 5-year survival and toxicity of moderately hypofractionated radiotherapy with simultaneous integrated boost (SIB) in (very) high-risk prostate cancer

Purpose

High-risk (HR) prostate cancer patients usually receive high-dose radiotherapy (RT) using a two-phase sequential technique, but data on a simultaneous integrated boost (SIB) technique are lacking. We prospectively evaluated the long-term results of urinary (GU) and digestive (GI) toxicity and survival data for high-dose RT using a SIB technique in HR and very high-risk (VHR) prostate cancer.

Methods

Patients were treated using an SIB technique in 34 fractions, at a dose of 54.4 Gy to the pelvis and seminal vesicles and 74.8 Gy to the prostate, combined with 36 months of androgen-depriving therapy in a prospective multicenter study. Acute and late GU and GI toxicity data were collected. Overall survival (OS), biochemical-relapse-free survival (bRFS), loco-regional-relapse-free survival (LRRFS), metastasis-free-survival (MFS) and disease-free-survival (DFS) were assessed.

Results

We recruited 114 patients. After a median follow-up of 62 months, very few patients experienced acute (M0-M3) (G3-4 GU = 3.7 %; G3-4 GI = 0.9 %) or late (M6-M60) severe toxicity (G3-4 GU = 5.6 %; G3-4 GI = 2.8 %). The occurrence of acute G2 + GU or GI toxicity was significantly related to the consequential late G2 + toxicity (p < 0.01 for both GU and GI). Medians of OS, bRFS, LRRFS, MFS and DFS were not reached. At 60 months, OS, bRFS, LRRFS, MFS and DFS were 88.2 % [82.1; 94.7], 86.0 % [79.4 %;93.2 %], 95.8 % [91.8 %;99.9 %], 87.2 % [80.9 %;94.0 %] and 84.1 % [77.2 %;91.6 %] respectively.

Conclusion

SIB RT at a dose of 54.4 Gy to the pelvis and 74.8 Gy to the prostate is feasible, leading to satisfying tumor control and reasonable toxicity in HR and VHR prostate cancer.

PSMA-PET-guided dose-escalated volumetric arc therapy for newly diagnosed lymph node-positive prostate cancer: 5 Year outcomes following the FROGG and EviQ node-positive guidelines

INTRODUCTION

The Royal Australian and New Zealand College of Radiologists (RANZCR) Faculty of Radiation Oncology Genitourinary Group (FROGG) guidelines and online EviQ protocols incorporate prostate-specific membrane antigen (PSMA) positron emission tomography (PET)-guided dose-escalated intensity-modulated radiation therapy (DE-IMRT) for newly diagnosed lymph node (LN) positive prostate cancer. We evaluated late toxicity and efficacy outcomes following the FROGG and EviQ approach.

METHODS

Patients with LN-positive-only metastases on PSMA-PET imaging were offered curative therapy with 3 months neoadjuvant androgen deprivation therapy (ADT) followed by DE-IMRT and 3 years adjuvant ADT. IMRT was delivered via volumetric arc therapy (VMAT). We aimed to deliver 81 Gy in 45 fractions (Fx) to the prostate and PET-positive LNs, and 60 Gy in 45 Fx to elective pelvic nodes, contoured using the PIVOTAL guidelines.

RESULTS

Forty-five patients were included. The median number of PET-positive nodes boosted was 2 (range 1-6) and median boost volume 1.16 cc (range 0.15-4.14). Seventeen (38%) patients had PET-positive nodes outside of PIVOTAL contouring guidelines. With 60 months median follow-up, disease-free, metastasis-free, prostate cancer-specific and overall survival were 88.1%, 95.3%, 100% and 91.5%. There were no in-field nodal failures. Late grade 1, 2 and 3 gastrointestinal toxicities occurred in 4%, 2% and 0% of patients, and genitourinary toxicity in 18%, 18% and 4%. Lower limb grade 2 lymphoedema occurred in three patients (7%).

CONCLUSION

Outcomes following FROGG guidelines and EviQ are promising, with high long-term disease control and low toxicity. Contouring guidelines require modification due to the high rate of PET-positive nodes demonstrated beyond recommended coverage.

Late Toxicity of Moderately Hypofractionated Intensity-Modulated Proton Therapy Treating the Prostate and Pelvic Lymph Nodes for High-Risk Prostate Cancer

PURPOSE

To evaluate late gastrointestinal (GI) and genitourinary (GU) toxicity of moderately hypofractionated intensity modulated proton therapy (IMPT) targeting the prostate and pelvic lymph nodes.

METHODS AND MATERIALS

A target accrual of 56 patients with high-risk or unfavorable intermediate risk prostate cancer were enrolled into a prospective study (ClinicalTrials.gov: NCT02874014) of moderately hypofractionated IMPT. IMPT with pencil beam scanning was used to deliver 6750 and 4500 cGy relative biological effectiveness in 25 daily fractions simultaneously to the prostate and pelvic lymph nodes, respectively. All received androgen deprivation therapy. Late GI and GU toxicity was prospectively assessed using Common Terminology Criteria for Adverse Events version 4.0, at baseline, weekly during radiation therapy, 3-month postradiation therapy, and then every 6 months. Actuarial rates of late GI and GU toxicity were estimated using Kaplan-Meier method.

RESULTS

Median age was 75.5 years. Fifty-four patients were available for late toxicity evaluation. Median follow-up was 43.9 months (range, 16-66). The actuarial rate of late grade ≥2 GI toxicity at both 2 and 3 years was 7.4% (95% confidence interval [CI], 0.2%-14.2%). The actuarial rate of late grade 3 GI toxicity at both 2 and 3 years was 1.9% (95% CI, 0%-5.4%). One patient experienced grade 3 GI toxicity with proctitis. The actuarial rate of late grade ≥2 GU toxicity was 20.5% (95% CI, 8.9%-30.6%) at 2 years, and 29.2 % (95% CI, 15.5%-40.7%) at 3 years. None had grade 3 GU toxicity. The presence of baseline GU symptoms was associated with a higher likelihood of experiencing late grade 2 GU toxicity.

CONCLUSIONS

A moderately hypofractionated IMPT targeting the prostate and regional pelvic lymph nodes was generally well tolerated. Patients with pre-existing GU symptoms had a higher rate of late grade 2 GU toxicity. A phase 3 study is needed to assess any therapeutic gain of IMPT, in comparison with photon-based radiation therapy.

"Meta-analysis of elective pelvic nodal irradiation using moderate hypofractionation for high-risk prostate cancer" (MENHYP-ENI)

OBJECTIVES

Despite several advances in planning and delivery of radiotherapy (RT) for prostate cancer, the role of elective pelvic nodal irradiation (EPNI) remains controversial for high-risk disease. We performed a meta-analysis to evaluate the outcomes of patients treated with moderate hypofractionated RT (MHF-RT) with EPNI using modern radiotherapy techniques.

METHODS

Eligible studies were identified on Medline, Embase, the Cochrane Library, and proceedings of annual meetings through October 2021. We followed the PRISMA and MOOSE guidelines. A meta-regression analysis was performed to assess a possible correlation between selected variables and outcomes. A p-value <0.05 was considered significant.

RESULTS

Eighteen studies with a total of 1745 patients, median follow-up 61 months, treated with EPNI employing MHF-RT were included. The biochemical relapse-free survival (bRFS) at 5-, 7- and 10-year was 90% (95% CI 88-94%), 83% (95%CI 78-91%) and 78% (95%CI 68-88%). The 5-year prostate cancer-specific survival, disease-free survival, distant metastases-free survival and overall survival were 98% (95%CI 97-99%), 88.7% (95%CI 85-93%), 91.2% (95%CI 88-92%), and 93% (95%CI 90-96%), respectively. The rates of local, pelvic, and distant recurrence were 0.38% (95%CI 0-2%), 0.13% (95%CI 0-1.5%), and 7.35% (95%CI 2-12%), respectively. The rate of late GI and GU toxicity grade ≥ 2 were 6.7% (95%CI 4-9%), and 11.3% (95%CI 7.6-15%), with heterogeneity, but with rare cases of toxicity grade 3-5.

CONCLUSION

EPNI with concomitant MHF-RT provides satisfactory bRFS in the long-term follow-up, with low rates of GU and GI severe toxicities and minimal pelvic and local failure.

Elective pelvic nodal irradiation with a simultaneous hypofractionated integrated prostate boost for localized high risk prostate cancer: Long term results from a prospective clinical trial

BACKGROUND

To report on long-term results of elective pelvic nodal irradiation (EPNI) and a simultaneous hypofractionated prostate boost for high-risk prostate cancer.

MATERIALS AND METHODS

This was a prospective single-arm study. Patients with high-risk disease (cT3, PSA >20 ng/mL, or Gleason score 8-10) were eligible. Patients received 45 Gy in 25 fractions to the prostate and pelvic lymph nodes with a simultaneous intensity-modulated radiotherapy boost of 22.5 Gy to the prostate (total dose 67.5 Gy in 25 fractions), with androgen deprivation therapy (ADT) for 2-3 years. The primary endpoint was biochemical failure. Secondary endpoints included distant metastases and overall survival. Multivariable analysis was performed to look for predictive factors. Late toxicity was assessed using CTCAE v3.0.

RESULTS

230 patients enrolled. Median follow-up was 11.2 years (IQR 8.1-12.9). At 10 years, cumulative incidence of biochemical failure was 33.4%, distant metastasis was 16.5%, and overall survival was 76.3%. On multivariable analysis, PSA nadir ≥0.05 ng/mL was associated with biochemical failure (HR 6.8, 95% CI 4-11.8, p < 0.001) and distant metastases (HR 7.5, 95% CI 3.9-14.5, p < 0.0001). PSA nadir ≥0.1 ng/mL (HR 5.2, 95% 2.2-12, p = 0.0001) and ADT use ≤12 months (versus >24 months) (HR 2.3, 95% CI 1.3-3.9, p = 0.004) were associated with worse survival. The 5-year cumulative incidence of any late grade ≥3 gastrointestinal and genitourinary toxicity was 2.3% and 7.5%, respectively.

CONCLUSION

EPNI and a simultaneous hypofractionated prostate boost combined with long-term ADT for high-risk prostate cancer resulted in acceptable 10-year biochemical control and survival with low grade ≥3 toxicity.