Prostate-Only Versus Whole-Pelvic Radiation Therapy in High-Risk and Very High-Risk Prostate Cancer (POP-RT): Outcomes From Phase III Randomized Controlled Trial

Five-Year Outcomes of Moderately Hypofractionated Proton Therapy Incorporating Elective Pelvic Nodal Irradiation for High-Risk Prostate Cancer

PURPOSE

To assess the efficacy of moderately hypofractionated intensity modulated proton therapy (IMPT) targeting the prostate/seminal vesicles and pelvic lymph nodes for high-risk (HR) or unfavorable intermediate-risk (UIR) prostate cancer (PCa).

MATERIALS AND METHODS

A prospective study (ClinicalTrials.gov: NCT02874014) of moderately hypofractionated IMPT accrued a target sample size of 56 patients with HR or UIR-PCa. The prostate/seminal vesicles and pelvic lymph nodes were treated simultaneously with 67.5 and 45 Gy, respectively, in 25 daily fractions. All received androgen deprivation therapy. Its primary objective was late gastrointestinal (GI) and genitourinary (GU) adverse events (AEs), and secondary objectives were a recurrence-free rate (RFR), including freedom from prostate-specific antigen (PSA) relapse and disease-free survival (DFS) at 5 years. PSA and AEs were evaluated at 3, 6, and 12 months post-IMPT, then every 6 months for 5 years, and then yearly thereafter. The actuarial rates of late GI and GU AEs, RFR, and DFS were estimated with the Kaplan-Meier method.

RESULTS

Median age was 75 years. Median PSA was 10.5 ng/mL. Fifty-three patients had HR-PCa; 2 had UIR-PCa. Median androgen deprivation therapy duration was 18 months. Median follow-up was 62 months. Late grade ≥2 and 3 GI AEs at 5 years were 16% and 4%, respectively. Late grade ≥2 and 3 GU AEs at 5 years were 41% and 0%, respectively. None had a grade ≥4 late AE. At 5 years, RFR and DFS were 90% and 89%, respectively. Seven patients had PCa recurrence, all detected by PSA relapse initially. Three patients died with PSA <0.1 ng/mL at last follow-up. None died of PCa or treatment-related AEs.

CONCLUSIONS

This regimen of moderately hypofractionated IMPT for HR or UIR-PCa yielded encouraging 5-year RFR, DFS, and late AE outcomes. A phase III study is needed to assess any therapeutic gain of IMPT compared with photon-based radiation therapy.

Pelvic Regional Control With 25 Gy in 5 Fractions in Stereotactic Radiation Therapy for High-Risk Prostate Cancer: Pooled Prospective Outcomes From the SHARP Consortium

PURPOSE

To evaluate the efficacy of 25 Gy in 5 fractions (25 Gy/5#) prophylactic pelvic nodal irradiation for regional control during stereotactic radiation therapy (SBRT) for high-risk prostate cancer.

METHODS AND MATERIALS

The multinational SHARP consortium database of patients treated with curative-intent prostate SBRT for high-risk prostate cancer was queried for prophylactic radiation therapy 25 Gy/5# to the pelvic lymph nodes. Details of Phoenix-defined biochemical failure and location of recurrence (local, regional, or distant) were extracted. Five-year biochemical failure-free survival (BFFS), metastasis-free survival, and overall survival were estimated by Kaplan-Meier method. Impact of potential prognostic factors (tumor stage, grade group [GG], prostate radiation therapy dose, and Androgen Deprivation Therapy (ADT) duration) was analyzed using Cox proportional hazards model.

RESULTS

A total of 171 patients were eligible for analysis. Two-thirds of the patients had GG 4-5 cancer. Prostate was irradiated to 40 Gy/5# in 51.5% of the cohort, whereas the rest received 35 to 36.25 Gy/5#. Median ADT duration was 15 months (IQR, 9-24). Over a median follow-up of 51 months, biochemical failure was recorded for 19 (11.1%) patients. Restaging with Prostate Specific Membrane Antigen (PSMA)-Positron Emission Tomography Computed Tomography (PETCT) showed recurrence within the pelvic nodes in 3 patients, all with co-occurring distant metastases. Overall pelvic control was 98.2%, with 5-year BFFS and overall survival being 86.1% and 89.3%, respectively. None of the prognostic factors showed a statistically significant impact on BFFS, except GG (adjusted HR 3.6 [95% CI, 0.9-13.0], P = .06).

CONCLUSIONS

For high-risk prostate cancer treated with SBRT, prophylactic pelvic nodal irradiation with 25 Gy/5# achieved near universal regional control.

Acute enteritis with pelvic SBRT: Influence of bowel delineation methods

Purpose

One fourth of the patients receiving SBRT to prostate and pelvis develop mild to moderate acute enteritis. In this study, we aim to study bowel dosimetry for different methods of bowel delineation in patients with and without acute bowel toxicity after whole-pelvic SBRT (WP-SBRT).

Methods and materials

In this prospective study, patients with high-risk prostate cancer treated with WP-SBRT were identified. Patients with acute bowel toxicity (CTCAE v5.0) were included as cases while those without were controls. All the patients had previously received 35-36.25 Gy in 5 fractions to the prostate and 25 Gy in 5 fractions to the pelvis. The bowel was contoured on the planning CT scan using seven different methods, namely- bowel bag (BB), small bowel loop (SB), large bowel loop (LB), combined bowel loop (BL) and bowel loops with margins (BL + 0.5 cm, BL + 1 cm and BL + 1.5 cm). The original clinically used plan was applied to all the contouring methods and dose-volume parameters studied.

Results

A total of 102 patients treated with WP-SBRT were screened and only those with properly documented acute toxicity were included for further analysis. While none of the patients had grade 3 bowel toxicity, 23 (22.5 %) patients had grade 1-2 acute enteritis, and 23 patients without were selected as cases and controls respectively. On visual assessment, the composite dose volume histogram (DVH) were similar for cases and controls for all the delineation methods studied. Objectively, the volume of the bowel structures receiving 7 Gy, 14 Gy, and 25 Gy did not show any statistically significant difference between cases and controls. One in five patients treated with WP-SBRT using bowel bag dose constraints of V7 < 1500 cc, V14 < 500 cc and V25 < 50 cc had acute enteritis.

Conclusion

There was no significant difference in planned bowel doses for different bowel delineation methods in patients with prostate cancer treated with WP-SBRT with or without acute bowel toxicity.

Pelvic Lymph Node Dissection in Prostate Cancer: Evidence and Implications

The role of extended pelvic lymph-node dissection (ePLND) in prostate cancer has been revisited in light of evidence from studies on staging via prostate-specific membrane antigen positron emission tomography/computed tomography. It is difficult to predict which individuals might benefit from ePLND. Patients should be counselled about this uncertainty and the risks of ePLND-associated morbidity as part of the shared decision-making process.

Integrating Prostate Specific Membrane Antigen-PET into Clinical Practice for Prostate Cancer

Prostate surface membrane antigen (PSMA)-PET imaging has significantly shaped the clinical management of prostate cancer, from localized to metastatic disease. It outperforms conventional imaging in both primary staging and detecting recurrence. PSMA-PET incorporation into the clinical workflow can alter treatment decisions, though the impact of observed stage migration on patient outcomes has yet to be well-characterized. There is growing interest in using PSMA-PET to predict treatment response across all stages of prostate cancer, and to select patients for PSMA radioligand therapy. Use of PSMA-PET will continue to expand for clinical applications as its role becomes better defined through prospective studies.

Prostate dose escalation may positively impact survival in patients with clinically node-positive prostate cancer definitively treated by radiotherapy: surveillance study of the Japanese Radiation Oncology Study Group (JROSG)

OBJECTIVE

To retrospectively analyze outcomes of patients who received definitive pelvic irradiation for clinically pelvic node-positive (cT1-4N1M0) prostate cancer (PCa).

MATERIALS AND METHODS

Clinical records of 148 patients with cT1-4N1M0 PCa treated with definitive pelvic radiotherapy (RT) between 2011 and 2015 were retrospectively collected from 25 institutions by the Japanese Radiation Oncology Study Group. The median age, initial prostate-specific antigen (PSA) level, and biologically effective dose (BED) to the prostate with α/β of 1.5 Gy were 69 (interquartile range [IQR], 65-74.3) years, 41.5 (IQR, 20.3-89) ng/ml, and 177.3 (IQR, 163.3-182) Gy, respectively. All patients underwent neoadjuvant androgen-deprivation therapy (ADT) for a median duration of 10 months. Most patients (141; 95.2%) received concurrent ADT during the irradiation period. The median duration of adjuvant ADT was 16 (IQR, 5-27.8) months. The Phoenix definition was used to assess biochemical failure.

RESULTS

The median follow-up period was 53.5 months (IQR, 41-69.3). The 5-year overall survival (OS) probability was 86.8%. The 5-year biochemical failure-free survival and clinical progression-free survival rates were 69.6% and 76.3%, respectively. Multivariate analysis indicated the BED to the prostate to be a significant prognostic factor for OS. Regarding late adverse events, the estimated cumulative incidences of late Grade 2 or higher gastrointestinal and genitourinary toxicities at 5 years were 8.2% and 5.8%, respectively.

CONCLUSION

Long-term ADT combined with definitive pelvic external beam RT for cT1-4N1M0 PCa leaded to favorable outcomes. Future prospective studies should validate the suggested survival benefit of local dose escalation to the prostate in this cohort.

Propensity Score Matched Analysis of External Beam Radiotherapy With or Without Focal Boost to Intraprostatic Lesions in Prostate Cancer

Background

This study evaluated the impact of radiotherapy (RT) with or without a simultaneous integrated boost (SIB) to intraprostatic lesions on survival, recurrence, and toxicity in localized prostate cancer (PCa). Key prognostic and predictive factors were also analyzed.

Materials and Methods

A retrospective analysis included 712 intermediate‐ and high‐risk PCa patients treated with external beam RT at 78 Gy, with or without SIB (up to 86 Gy), between 2010 and 2018. Propensity score matching (PSM) was used to ensure comparability. Outcomes assessed included biochemical disease‐free survival (bDFS), prostate cancer‐specific survival (PCSS), local recurrence (LR), distant metastasis (DM), and treatment‐related toxicities.

Results

After PSM, 417 patients were analyzed (208 with SIB, 209 without). Over a median follow‐up of 8.6 years, the SIB group showed higher 8‐year bDFS (93.8% vs. 83.5%; p = 0.006) and lower rates of DM (6.1% vs. 13.0%; p = 0.003) and LR (1.8% vs. 6.9%; p = 0.03). PCSS was similar between groups (95.7% vs. 92.3%; p = 0.38). Advanced T stage and absence of SIB were predictors of worse bDFS, DM, and LR, while higher Gleason score were associated with poorer PCSS and DM in multivariable analysis. There were no significant differences in 8‐year Grade ≥ 2 GU (10.1% vs. 10.5%; p = 0.98) or GI (7.8% vs. 6.5%; p = 0.64) toxicities between the SIB and non‐SIB groups.

Conclusions

SIB with external beam RT significantly improves bDFS and reduces LR and DM in intermediate‐ and high‐risk PCa, with no increase in significant toxicities. These findings emphasize the value of dose escalation in achieving better local control and long‐term outcomes while maintaining patient safety.

Hypofractionated Dose Escalation Radiotherapy for High-Risk Prostate Cancer: the survival analysis of the Prostate Cancer Study-5 (PCS-5), a GROUQ-led phase III trial

BACKGROUND AND OBJECTIVE

Prostate Cancer Study 5 (PCS5) compared conventional fractionated radiotherapy (CFRT) with hypofractionated radiotherapy (HFRT) in high-risk prostate cancer (PCa) patients, hypothesizing similar toxicity and survival outcomes. This report presents the efficacy analysis.

METHODS

PCS5 is a Canadian multicenter, open-label, phase 3 randomized control trial. Men with histologically proven, clinically localized PCa with one or more high-risk features (T3/T4, Gleason score ≥8, and prostate-specific antigen >20) were eligible. Patients were randomized 1:1 to CFRT (76 Gy/38 fractions [Fx] to the prostate and 46 Gy/23 Fx to the pelvic lymph nodes [PLNs]) or HFRT (68 Gy/25 Fx to the prostate and 45 Gy/25 Fx to the PLNs) and 28 mo of androgen suppression. The primary endpoint was toxicity; secondary endpoints included survival outcomes.

KEY FINDINGS AND LIMITATIONS

Of 329 patients, 164 were randomized to HFRT and 165 to CFRT, with 159 in the HFRT arm and 160 in the CFRT arm included in survival analyses. At the 5-yr median follow-up, there were no significant differences in overall survival (OS; 90.3% vs 89.7%; risk ratio [RR]: 1.01; 95% confidence interval [CI]: 0.93-1.09), PCa-specific survival (PCSS; 97.4% vs 97.5%; RR: 1.00; 95% CI: 0.93-1.07), biochemical recurrence-free survival (BCRFS; 85.2% vs 85.2%; RR: 1.00; 95% CI: 0.91-1.10), or distant metastasis-free survival (DMFS; 87.1% vs 87.1%; RR: 1.00; 95% CI: 0.92-1.09). Hazard ratios were 0.92 (95% CI: 0.56-1.53) for OS, 1.31 (95% CI: 0.46-3.78) for PCSS, 0.85 (95% CI: 0.56-1.30) for BCRFS, and 0.90 (95% CI: 0.56-1.43) for DMFS. Sample size was a limiting factor.

CONCLUSIONS AND CLINICAL IMPLICATIONS

There were no differences in survival outcomes between HFRT (68 Gy/25 Fx) and CFRT (76 Gy/38 Fx). HFRT, including PLN radiotherapy and long-term androgen deprivation therapy, should be considered a new standard of care for high-risk PCa patients undergoing external beam radiotherapy.

Bladder Adjuvant Radiation Therapy (BART): Acute and Late Toxicity From a Phase III Multicenter Randomized Controlled Trial

PURPOSE

To report toxicity from the multicenter phase III randomized trial of Bladder Adjuvant Radiation Therapy (BART) after radical cystectomy and chemotherapy in high-risk muscle-invasive bladder cancer (MIBC).

METHODS AND MATERIALS

Patients with nonmetastatic urothelial MIBC with ≥1 high-risk feature after radical cystectomy- pT3-4, pN1-3, nodal yield <10, positive margin, or ≥cT3 downstaged with neoadjuvant chemotherapy- were randomized 1:1 to observation (Obs) or adjuvant radiation therapy (RT) at 4 centers, stratified by pN stage (N0, N+) and chemotherapy (neoadjuvant, adjuvant, none). Stoma-sparing image guided intensity modulated RT 50.4 Gy in 28# was prescribed to the cystectomy bed and pelvic nodes. Acute toxicity (≤3 months of RT/randomization) and late toxicity were assessed per protocol using Common Terminology Criteria for Adverse Event v5.0. Patients progressing within 3 or 6 months of randomization were excluded from acute or late toxicity analysis, respectively.

RESULTS

The BART trial enrolled 153 patients (Obs = 76, RT = 77). About half (49%) had pN+. Nearly 90% received chemotherapy (70% neoadjuvant; most commonly gemcitabine plus cisplatin). In the RT arm, 63/77 completed RT per protocol with no toxicity-related RT termination. Of the 134 patients analyzable for acute toxicity, no difference was observed in grade 3 (Obs 4.2% vs RT 1.6%, P = .34). Grade 2 effects were higher with RT (17.5% vs 1.1%, P < .001), mainly diarrhea/enteritis or proctitis. Late toxicity was analyzable for 104 patients (Obs = 57, RT = 47) with a median follow-up of 27 months. Grades 3 to 4 toxicity were about 10% (Obs 10.5% vs RT 8.4%, P = .62), and cumulative late grade 2+ toxicity was similar in both groups (17.5% vs 23.3%, P = .27).

CONCLUSIONS

In the largest trial of adjuvant RT for high-risk urothelial MIBC, severe acute and late toxicity were low and similar with obervation or radiation therapy. The oncological outcomes are awaited.

Escalating the dose of high-dose-rate brachytherapy combined with external beam radiotherapy improves the disease control rate in patients with high- or very-high-risk prostate cancer

PURPOSE

High-dose-rate brachytherapy (HDR-BT) combined with external beam radiotherapy (EBRT) is an effective treatment for patients with high- and very-high-risk prostate cancer. We sought to identify the factors associated with reduced biochemical recurrence rates following HDR-BT.

METHODS

A total of 304 patients with high- or very-high-risk prostate cancer who underwent HDR-BT and EBRT were analyzed. EBRT comprised 50 Gy in 25 fractions and HDR-BT comprised 18 Gy in 2 fractions. Biochemical recurrence was defined as an increase in prostate specific antigen (PSA) by ≥2.0 ng/mL from the nadir level.

RESULTS

The median follow-up time was 8.2 years (range, 3.4‒13.7 years) after HDR-BT. The 5-year biochemical progression-free survival (bPFS), overall survival, and cause-specific survival rates were 87.4%, 93.3%, and 100%, respectively. In univariate and multivariable analyses, a biologically effective dose (α/β = 1.5) ≥ 240 Gy and androgen deprivation therapy (ADT) were significantly associated with better bPFS (p = 0.020 and 0.007, respectively), whereas pretreatment PSA ≥ 40 ng/mL and Gleason score group 5 were significantly associated with worse bPFS (p = 0.080 and 0.021, respectively). Grade ≥ 3 rectal toxicities occurred in 0.3% of patients and grade ≥ 3 urinary toxicities occurred in 3.4% of patients.

CONCLUSION

In patients with high- and very-high-risk prostate cancer treated with EBRT and HDR-BT, dose escalation and ADT were associated with improved tumor control. By comparison, Gleason score group 5 and pretreatment PSA >40 ng/mL were associated with worse tumor control.

« Augmented radiotherapy » in the management of high-risk prostate cancer (PCa): A systematic review

BACKGROUND

In patients with high-risk (HR) prostate cancer (PCa) treated with radiotherapy and androgen deprivation therapy (ADT), intensification with androgen receptor pathway inhibitor (ARPI) improves overall survival (OS), at the cost of significant side-effects. We hypothesized that "augmented RT" schedules (defined as either dose-escalation on the prostate gland over 78 Gy and/or addition of whole pelvic radiotherapy (WPRT)), combined with long-term ADT can reach excellent prostate cancer specific survival (PCSS) in this population with little detrimental impact on quality of life.

METHODS

We searched Pubmed database until February 8, 2024. Studies reporting both oncological and toxicity outcomes after "augmented RT" were deemed eligible. Studies without ADT or with ARPI intensification were deemed ineligible.

RESULTS

Dose-escalation within the prostate gland at doses over 78 Gy halved the risk of biochemical recurrence at 5 years, with however no impact on PCSS. The addition of WPRT provides a 5-year disease-free survival (DFS) reaching 89.5 % at 5 years, with no significant increase in late grade≥ 2 genito-urinary (GU) or gastrointestinal (GI) toxicity. Combined approaches result in 9-year PCSS ranging between 96.1 % and 100 %. Most approaches demonstrated excellent safety profiles.

CONCLUSIONS

"Augmented RT" reached excellent oncological outcomes, with minimal additional toxicity. The development of biomarkers might lead to further treatment personalization, in the rapidly evolving landscape of systemic therapies.

Elective pelvic nodal irradiation for elderly patients with high-risk prostate cancer: A more patient-oriented approach

The role of elective pelvic nodal irradiation (EPNI) for high-risk prostate cancer (hrPC) management is still an open issue, especially for the elderly patients. It is unclear whether older patients can experience the same benefit from the treatment strategies used for younger men. Hence, in absence of solid data, it appears reasonable to pursuit a shared decision-making process so that older patients can express their informed preferences about the different treatment options. In this letter, we discuss why caution appears reasonable on EPNI trade-off in hrPC patients aged 75 years or more.

Optimizing treatment for Gleason 10 prostate cancer: radiation dose escalation and 68Ga-PSMA-PET/CT staging

PURPOSE

This study aimed to investigate the effects of dose escalation through focal boost (FB) to intraprostatic lesions (IPLs) as well as the role of gallium-68 prostate-specific membrane antigen positron-emission tomography (68Ga-PSMA-PET/CT) for staging and treatment planning in patients with Gleason score (GS) 10 prostate cancer (PCa) receiving definitive radiotherapy (RT) and androgen deprivation therapy (ADT).

MATERIALS AND METHODS

We retrospectively analyzed data of 92 patients with GS 10 PCa who underwent definitive RT and ADT from March 2010 to October 2022. Freedom from biochemical failure (FFBF), prostate cancer-specific survival (PCSS), distant metastasis-free survival (DMFS), and overall survival (OS) rates were calculated using the Kaplan-Meier method. Survival outcomes were compared between patients staged with 68Ga-PSMA-PET/CT and those staged with conventional imaging modalities as well as between those who received a simultaneous integrated boost (SIB) and those who did not.

RESULTS

At a median follow-up time of 73 months, the 5‑year FFBF, PCSS, DMFS, and OS rates were 59.2%, 77.0%, 62.9%, and 67.6%, respectively. Disease progression was observed in 39 patients (42.4%), with most cases manifesting as distant metastasis (DM). A total of 56 patients (60.9%) were staged using 68Ga-PSMA-PET/CT, while 43 patients (46.7%) received FB to IPLs. Patients staged with 68Ga-PSMA-PET/CT had better FFBF and PCSS compared to those staged with conventional imaging. Patients undergoing an SIB had improved PCSS and DMFS. In the multivariable analysis, an ADT duration of 18 months or more was associated with improved FFBF, PCSS, DMFS, and OS. Application of an SIB was an additional independent predictor for improved FFBF, while staging with 68Ga-PSMA-PET/CT was associated with better PCSS.

CONCLUSION

We found that long-term ADT, increasing the radiation dose to primary tumor, and staging with 68Ga-PSMA-PET/CT improved clinical outcomes. Additional research is needed for validation.

Radioprotection of healthy tissue via nanoparticle-delivered mRNA encoding for a damage-suppressor protein found in tardigrades

Patients undergoing radiation therapy experience debilitating side effects because of toxicity arising from radiation-induced DNA strand breaks in normal peritumoural cells. Here, inspired by the ability of tardigrades to resist extreme radiation through the expression of a damage-suppressor protein that binds to DNA and reduces strand breaks, we show that the local and transient expression of the protein can reduce radiation-induced DNA damage in oral and rectal epithelial tissues (which are commonly affected during radiotherapy for head-and-neck and prostate cancers, respectively). We used ionizable lipid nanoparticles supplemented with biodegradable cationic polymers to enhance the transfection efficiency and delivery of messenger RNA encoding the damage-suppressor protein into buccal and rectal tissues. In mice with orthotopic oral cancer, messenger RNA-based radioprotection of normal tissue preserved the efficacy of radiation therapy. The strategy may be broadly applicable to the protection of healthy tissue from DNA-damaging agents.

Stereotactic body radiotherapy (SBRT) as a treatment for localized prostate cancer: a retrospective analysis

BACKGROUND

External beam radiotherapy (EBRT) is a standard treatment for localized prostate cancer, with recent advancements favoring a reduced number of treatment sessions. Stereotactic body radiotherapy (SBRT) is a form of radiotherapy that delivers higher doses per fraction, typically in five or fewer sessions. This retrospective study aims to evaluate the implementation of the PACE-SBRT protocol for localized prostate cancer at our center by assessing the incidence and severity of toxicity, as well as biochemical relapse-free survival.

METHODS

We conducted a retrospective analysis of patients with localized prostate cancer treated with SBRT at the Iridium Network in Antwerp, Belgium, who were treated between January 1, 2020, and December 31, 2022. Data were extracted from electronic medical records and included descriptive information on patient outcomes. Acute and late genitourinary (GU) and gastrointestinal (GI) toxicities were graded according to the Common Terminology Criteria for Adverse Events (CTCAE) version 4.0. Acute toxicity was defined as events occurring within 90 days post-SBRT, whereas late toxicity was evaluated at 6 months, 1 year, 2 years, and 3 years post treatment. Biochemical recurrence was defined via the Phoenix criteria, as a rise in PSA levels of 2 ng/mL or more above the post treatment nadir.

RESULTS

A total of 267 patients met the eligibility criteria for this study. In total, 9% of patients were low risk, 51% were intermediate risk, and 40% were high risk. The cumulative incidence of Grade 2 or higher GU toxicity was 27%, and for GI toxicity, it was 2%. At 24 months, 11.5% (20/175) of patients experienced CTCAE grade 2 or higher GU toxicity, and 1.7% (3/175) experienced grade 2 or higher GI toxicity. Biochemical relapse occurred in 1.5% (4/267) of patients, leading to a 2-year biochemical relapse-free survival rate of 98.5%.

CONCLUSION

SBRT for localized prostate cancer has favorable oncological outcomes with a low incidence of Grade 2 or higher toxicity. The results of this study are consistent with findings from prospective trials, suggesting that SBRT is an effective treatment modality. Trial registration Retrospectively registered.

Refining Risk Stratification of High-risk and Locoregional Prostate Cancer: A Pooled Analysis of Randomized Trials

BACKGROUND AND OBJECTIVE

Radiotherapy (RT) and long-term androgen deprivation therapy (ltADT; 18-36 mo) is a standard of care in the treatment of high-risk localized/locoregional prostate cancer (HRLPC). We evaluated the outcomes in patients treated with RT + ltADT to identify which patients have poorer prognosis with standard therapy.

METHODS

Individual patient data from patients with HRLPC (as defined by any of the following three risk factors [RFs] in the context of cN0 disease-Gleason score ≥8, cT3-4, and prostate-specific antigen [PSA] >20 ng/ml, or cN1 disease) treated with RT and ltADT in randomized controlled trials collated by the Intermediate Clinical Endpoints in Cancer of the Prostate group. The outcome measures of interest were metastasis-free survival (MFS), overall survival (OS), time to metastasis, and prostate cancer-specific mortality. Multivariable Cox and Fine-Gray regression estimated hazard ratios (HRs) for the three RFs and cN1 disease.

KEY FINDINGS AND LIMITATIONS

A total of 3604 patients from ten trials were evaluated, with a median PSA value of 24 ng/ml. Gleason score ≥8 (MFS HR = 1.45; OS HR = 1.42), cN1 disease (MFS HR = 1.86; OS HR = 1.77), cT3-4 disease (MFS HR = 1.28; OS HR = 1.22), and PSA >20 ng/ml (MFS HR = 1.30; OS HR = 1.21) were associated with poorer outcomes. Adjusted 5-yr MFS rates were 83% and 78%, and 10-yr MFS rates were 63% and 53% for patients with one and two to three RFs, respectively; corresponding 10-yr adjusted OS rates were 67% and 60%, respectively. In cN1 patients, adjusted 5- and 10-yr MFS rates were 67% and 36%, respectively, and 10-yr OS was 47%.

CONCLUSIONS AND CLINICAL IMPLICATIONS

HRLPC patients with two to three RFs (and cN0) or cN1 disease had the poorest outcomes on RT and ltADT. This will help in counseling patients treated in routine practice and in guiding adjuvant trials in HRLPC.

PATIENT SUMMARY

Radiotherapy and long-term hormone therapy are standard treatments for high-risk and locoregional prostate cancer. In this report, we defined prognostic groups within high-risk/locoregional prostate cancer and showed that outcomes to standard therapy are poorest in those with two or more "high-risk" factors or evidence of lymph node involvement. Such patients may therefore be the best candidates for intensification of treatment.

Management of Patients with Advanced Prostate Cancer. Report from the 2024 Advanced Prostate Cancer Consensus Conference (APCCC)

BACKGROUND AND OBJECTIVE

Innovations have improved outcomes in advanced prostate cancer (PC). Nonetheless, we continue to lack high-level evidence on a variety of topics that greatly impact daily practice. The 2024 Advanced Prostate Cancer Consensus Conference (APCCC) surveyed experts on key questions in clinical management in order to supplement evidence-based guidelines. Here we present voting results for questions from APCCC 2024.

METHODS

Before the conference, a panel of 120 international PC experts used a modified Delphi process to develop 183 multiple-choice consensus questions on eight different topics. Before the conference, these questions were administered via a web-based survey to the voting panel members ("panellists").

KEY FINDINGS AND LIMITATIONS

Consensus was a priori defined as ≥75% agreement, with strong consensus defined as ≥90% agreement. The voting results show varying degrees of consensus, as discussed in this article and detailed in the Supplementary material. These findings do not include a formal literature review or meta-analysis.

CONCLUSIONS AND CLINICAL IMPLICATIONS

The voting results can help physicians and patients navigate controversial areas of clinical management for which high-level evidence is scant or conflicting. The findings can also help funders and policymakers in prioritising areas for future research. Diagnostic and treatment decisions should always be individualised on the basis of patient and cancer characteristics, and should incorporate current and emerging clinical evidence, guidelines, and logistic and economic factors. Enrolment in clinical trials is always strongly encouraged. Importantly, APCCC 2024 once again identified important gaps (areas of nonconsensus) that merit evaluation in specifically designed trials.

Evolving Paradigms in Prostate Cancer: The Integral Role of Prostate-Specific Membrane Antigen Positron Emission Tomography/Computed Tomography in Primary Staging and Therapeutic Decision-Making

Prostate-specific membrane antigen (PSMA) positron emission tomography or computed tomography (PET/CT) has emerged as a superior imaging option to conventional imaging for prostate cancer. The majority of early evidence and prospective trials evaluated PSMA PET/CT in the biochemical recurrence or metastatic setting. However, there has been an increasing number of prospective trials in the primary setting. The purpose of this narrative review was to describe the role of PSMA PET/CT in localized primary prostate cancer. This narrative review focuses on the prospective evidence available in this setting. We detail the current practice and future potential for PSMA PET/CT to be used in multiple stages of localized primary prostate cancer. The most common practice currently for PSMA PET/CT is in the primary nodal and metastatic staging of high-risk prostate cancer. We describe other roles of PSMA PET/CT, including in intermediate-risk prostate cancer as well as local staging and the impact on radiation therapy and surgical management. We also discuss the potential future roles of PSMA PET/CT in prediagnosis such as risk stratification for biopsy, prognosis, and specific surgical roles. Potential pitfalls of PSMA PET/CT are also addressed. PSMA PET/CT has already had a significant influence on prostate cancer, and there will continue to be a greater role for this imaging modality in localized primary prostate cancer.

Quality Assurance in Radiotherapy (RT)-Specific Trials: Indian Scenario

AIMS

There is evidence that proper radiotherapy trial quality assurance (RTTQA) translates into improved outcomes for patients. However, the practice of RTTQA is heterogeneous and implemented in a diverse manner across trials. In this paper, we review the RTTQA report for randomised trials (RCT) conducted in India and present our experience with RTTQA for various clinical trials and highlight the key achievements and challenges.

MATERIALS AND METHODS

Search was performed using the keywords and the variations thereof for "radiotherapy" and author affiliations from India, its states and major metropolitan cities. Pubmed search filters were used to restrict results to RCT published in the past 5 years (2019-2024). Reporting of RTTQA procedures from publications and protocols was documented along with the protocol-specified dosimetric goals. We also evaluated a few clinical trials performed in the Department of Radiation Oncology at Tata Medical Center. The different RTTQA procedures and results for four representative clinical trials have been described.

RESULTS

A formal RTTQA process was reported by only one out of 24 randomised controlled trials and formal dosimetric goals were pre-specified by 9 of 13 trials where IMRT was used as treatment. RTTQA requirements were tailored for each clinical trial at Tata Medical Center. For the HYPORT trial, the RTTQA process focused on ensuring the matchline doses were homogenous. HYPORT B trial commissioned the use of a simultaneous integrated boost technique which emphasised conformal avoidance of dose spillage to contralateral breast and lung. HYPORT Adjuvant and PROPARA trials are multicentre clinical trials. While HYPORT Adjuvant focussed on ensuring that the dose delivery met the predefined constraints, segmentation of the target volume was important for the PROPARA trial.

CONCLUSION

We demonstrate different RTTQA procedures required for representative clinical trials and highlight key challenges encountered.

Controversies in the use of next-generation imaging for evaluation and treatment decision-making in patients with prostate cancer after biochemical recurrence: views from a Spanish expert panel

INTRODUCTION

Diagnosing and managing biochemical recurrence (BCR) of prostate cancer (PCa) following primary radical treatment remain a challenge. Implementing next-generation imaging (NGI) techniques has improved metastases detection. However, access to these techniques is heterogeneous, and controversies surround their use and subsequent treatment decisions. In November 2023, a multidisciplinary expert meeting was organized to discuss these aspects. This information was further reviewed in November 2024.

AREAS COVERED

NGI-specific tracers' selection, evidence supporting patient selection for NGI after BRC, current treatment strategies in patients with BRC, and the role of NGIs in current and future therapeutic approaches.

EXPERT OPINION

Despite improved detection performance compared to conventional imaging techniques, the application of NGIs to treatment decision-making and the impact on patient outcomes are yet to be proven. Given the lack of guidance, opinions and recommendations from multidisciplinary expert panels are valuable for diagnosing and adequately treating patients with BRC after radical treatment.

The risk of second malignancies following prostate cancer radiotherapy in the era of conformal radiotherapy: a statement of the Prostate Cancer Working Group of the German Society of Radiation Oncology (DEGRO)

A significant number of prostate cancer patients are long-term survivors after primary definitive therapy, and the occurrence of late side effects, such as second primary cancers, has gained interest. The aim of this editorial is to discuss the most current evidence on second primary cancers based on six retrospective studies published in 2021-2024 using large data repositories not accounting for all possible confounding factors, such as smoking or pre-existing comorbidities. Overall, prostate cancer patients treated with curative radiotherapy have an increased risk (0.7-1%) of the development of second primary cancers compared to patients treated with surgery up to 25 years after treatment. However, current evidence suggests that the implementation of intensity modulated radiation therapy is not increasing the risk of second primary cancers compared to conformal 3D-planned radiotherapy. Furthermore, increasing evidence indicates that highly conformal radiotherapy techniques may not increase the probability of second primary cancers compared to radical prostatectomy. Consequently, future studies should consider the radiotherapy technique and other confounding factors to provide a more accurate estimation of the occurrence of second primary cancers.

Moderate-Hypofractionated Radical Radiotherapy for Early-Stage Prostate Cancer: A Propensity Score Matching Analysis Comparing Dose Fractionation Patterns

IntroductionThis study evaluates the clinical outcomes, survival benefits, and toxicities of two moderate-hypofractionated radiotherapy (MHRT) patterns, 60 Gy in 20 fractions (60 Gy/20f) and 70 Gy in 28 fractions (70 Gy/28f), in early-stage prostate cancer patients.MethodsThis retrospective study analyzed data from 187 patients diagnosed between 2014 and 2023, using propensity score matching to ensure efficacy assessment accuracy. The primary endpoints reported were overall survival (OS) and disease-free survival (DFS), calculated using Kaplan-Meier analysis. Toxicity and side effects were evaluated using Criteria for Adverse Events v5.0, focusing on the urinary and gastrointestinal (GI) systems.ResultsAfter matching, each of the 60 Gy and 70 Gy groups included 73 patients. The median follow-up duration for all patients was 36.0 months. The OS rates for the 60 Gy and 70 Gy groups were 86.3% and 89.0%, respectively, with 3-year OS rates of 92.4% and 89.0% (P = 0.375). The 3-year DFS rates were 91.0% in the 60 Gy group and 81.0% in the 70 Gy group (P = 0.096), indicating no significant differences between the groups. The incidence of acute Grade 2 or higher urinary toxicities was comparable between the two groups (60 Gy group vs 70 Gy group: 9.6% vs 9.6%, P = 1.0), while the 70 Gy group demonstrated an advantage for late Grade 2 or higher toxicities (60 Gy group vs 70 Gy group: 12.3% vs 2.8%, P = .028). For the GI system, the incidence of acute toxicities was higher in the 60 Gy group, albeit not statistically significant (60 Gy group vs 70 Gy group: 11.0% vs 6.8%, P = .383), while late toxicities were equivalent between the groups (60 Gy group vs 70 Gy group: 1.4% vs 1.4%, P = 1.0).ConclusionBoth MHRT fractionation patterns demonstrate comparable survival outcomes and toxicities in early-stage prostate cancer, suggesting MHRT's viability as a primary treatment. The 60 Gy/20f pattern marginally favored survival, albeit not with statistical significance.

Biochemical control in intermediate- and high-risk prostate cancer after EBRT with and without brachytherapy boost

PURPOSE

External beam radiotherapy (EBRT) with or without brachytherapy boost (BTB) has not been compared in prospective studies using guideline-recommended radiation dose and recommended androgen-deprivation therapy (ADT). In this multicenter retrospective analysis, we compared modern-day EBRT with BTB in terms of biochemical control (BC) for intermediate-risk (IR) and high-risk (HR) prostate cancer.

METHODS

Patients were treated for primary IR or HR prostate cancer during 1999-2019 at three high-volume centers. Inclusion criteria were prescribed ≥ 76 Gy EQD2 (α/β = 1.5 Gy) for IR and ≥ 78 Gy EQD2 (α/β = 1.5 Gy) for HR as EBRT alone or with BTB. All HR patients received ADT and pelvic irradiation, which were optional in IR cases. BC between therapies was compared in survival analyses.

RESULTS

Of 2769 initial patients, 1176 met inclusion criteria: 468 HR (260 EBRT, 208 BTB) and 708 IR (539 EBRT, 169 BTB). Median follow-up was 49 and 51 months for HR and IR, respectively. BTB patients with ≥ 113 Gy EQD2Gy experienced a stable, good BC outcome compared with BTB at lower doses. Patients treated with ≥ 113 Gy EQD2Gy also experienced significantly improved BC compared with EBRT (10-year BC failure rates after ≥ 113 Gy BTB and EBRT: respectively 20.4 and 41.8% for HR and 7.5 and 20.8% for IR).

CONCLUSIONS

In patients with IR and HR prostate cancer, BTB with ≥ 113 Gy EQD2Gy offered a BC advantage compared with dose-escalated EBRT and lower BTB doses.

2023/2024 update of the national prostate cancer guidelines in Sweden

N/A.

Cancer research in South Asian Association for Regional Cooperation (SAARC) countries

Cancer is a major global health threat, with 35 million new cases projected by 2050, predominantly in low-income and middle-income-countries. Within South Asian Association for Regional Cooperation (SAARC) countries, a notable gap in cancer research investment and output compared with high-income countries highlights the need to strengthen research capacity. The rising cancer incidence across SAARC countries is not being matched by local research, particularly in clinical trials in molecular biology, targeted therapy, immunotherapy, and cancer vaccines. This paucity of research is problematic as guidelines and therapies developed in high-income countries might not be directly applicable to low-income and middle-income countries due to distinct regional sociocultural, genetic, and environmental factors and are often impractical in these countries due to cost and implementation challenges. This Series paper examines the cancer research landscape within SAARC countries, focusing on Bangladesh, Nepal, Sri Lanka, India, Pakistan, Afghanistan, Bhutan, and Maldives. We analyse PubMed publication rates and examine available infrastructure, current research (including clinical trials), and limitations and disparities among SAARC countries in terms of cancer research. Key challenges include disparities in health-care access, cultural and economic barriers, and little funding and infrastructure. Strengthening cancer research in SAARC countries requires building collaborative networks, improving research facilities and training, focusing on local epidemiological studies, and developing affordable technologies and treatments. Effective policy and stakeholder engagement could greatly advance cancer care in the region.

Salvage lymphadenectomy or radiation therapy in prostate cancer patients with biochemical recurrence and PET positive lymph nodes after radical prostatectomy: A systematic review and pooled analysis

OBJECTIVE

To analyze the oncologic outcomes of biochemical recurrence (BCR) patients who received salvage treatment of lymph node dissection (LND) or radiation therapy (RT) for positron emission tomography (PET)-positive lymph node recurrences following radical prostatectomy (RP).

METHODS

Research using the MEDLINE, Cochrane, and Web of Science databases was conducted until June 2023. Inclusion criteria were BCR patients that received salvage LND or RT for PET-positive lymph node recurrence following primary RP for prostate cancer. Studies with a follow-up period of less than 12 months were excluded.

RESULTS

This study included 2476 patients (995 LND, 1481 RT) from 19 publications. The pooled incidences were 51.1 % and 74.3 % in PSA response, 69.8 % and 26.9 % in PSA progression, 41.5 % and 26.9 % in image progression, 41.5 % and 32.0 % in systemic progression, 0.9 % and 0.5 % in overall mortality, and 6.5 % and 1.3 % in cancer-specific mortality in LND and RT, respectively. Limitations include high heterogeneity.

CONCLUSION

Although heterogeneity is high across all studies, the pooled rates of PSA, image, and systemic progressions are higher in LND than in RT concerning BCR patients with PET-positive lymph nodes. For future trial designs in BCR, assessing the optimal timing of PSMA PET scans, concurrent systemic therapy, and salvage therapy type is imperative.

Elective pelvic nodal irradiation in the setting of ultrahypofractionated versus moderately hypofractionated and conventionally fractionated radiotherapy for prostate cancer: Outcomes from 3 prospective clinical trials

Background and purpose

Data is needed regarding the use of ultrahypofractionated radiotherapy (UHRT) in the context of prostate cancer elective nodal irradiation (ENI), and how this compares to conventionally fractionated radiotherapy (CFRT) ENI with CFRT or moderately hypofractionated radiotherapy (MHRT) to the prostate.

Materials and methods

Between 2011-2019, 3 prospective clinical trials of unfavourable intermediate or high-risk prostate cancer receiving CFRT (78 Gy in 39 fractions to prostate; 46 Gy in 23 fractions to pelvis), MHRT (68 Gy in 25 fractions to prostate; 48 Gy to pelvis), or UHRT (35-40 Gy in 5 fractions to prostate +/- boost to 50 Gy to intraprostatic lesion; 25 Gy to pelvis) were conducted. Primary endpoints included biochemical failure (Phoenix definition), and acute and late toxicities (CTCAE v3.0/4.0).

Results

Two-hundred-forty patients were enrolled: 90 (37.5 %) had CFRT, 90 (37.5 %) MHRT, and 60 (25 %) UHRT. Median follow-up time was 71.6 months (IQR 53.6-94.8). Cumulative incidence of biochemical failure (95 % CI) at 5-years was 11.7 % (3.5-19.8 %) for CFRT, 6.5 % (0.8-12.2 %) MHRT, and 1.8 % (0-5.2 %) UHRT, which was not significantly different between treatments (p = 0.38). Acute grade ≥ 2 genitourinary toxicity was significantly worse for UHRT versus CFRT and MHRT, but not for acute grade ≥ 3 genitourinary, or acute gastrointestinal toxicities. UHRT was not associated with worse late toxicities.

Conclusion

ENI with UHRT resulted in similar oncologic outcomes to CFRT ENI with prostate CFRT/MHRT, with worse acute grade ≥ 2 GU toxicity but no differences in late toxicity. Randomized phase 3 trials of ENI using UHRT techniques are much anticipated.

Quantifying dose perturbations in high-risk prostate radiotherapy due to translational and rotational motion of prostate and pelvic lymph nodes

BACKGROUND

Radiotherapy of the prostate and the pelvic lymph nodes (LN) is a part of the standard of care treatment for high-risk prostate cancer. The independent translational and rotational (i.e., six-degrees-of-freedom, [6DoF]) motion of the prostate and LN target during and between fractions can perturb the dose distribution. However, no standard dose reconstruction method accounting for differential 6DoF target motion is available.

PURPOSE

We present a framework for monitoring motion-induced dose perturbations for two independently moving target volumes in 6DoF. The framework was used to determine the dose perturbation for the prostate and the LN target caused by differential 6DoF motion for a cohort of high-risk prostate cancer patients. As a potential first step toward real-time dose-guided high-risk prostate radiotherapy, we furthermore investigated if the dose reconstruction was fast enough for real-time application for both targets.

METHODS

Twenty high-risk prostate cancer patients were treated with 3-arc volumetric modulated arc therapy (VMAT). Kilovoltage intrafraction monitoring (KIM) with triggered kilovoltage (kV) images acquired every 3 throughout 7-10 fractions per patient was used for retrospective 6DoF intrafraction prostate motion estimation. The 6DoF interfraction LN motion was determined from a pelvic bone match between the planning CT and a post-treatment cone beam CT (CBCT). Using the retrospectively extracted motion, real-time 6DoF motion-including dose reconstruction was simulated using the in-house developed software DoseTracker. A data stream with the 6DoF target positions and linac parameters was broadcasted at a 3-Hz frequency to DoseTracker. In a continuous loop, DoseTracker calculated the target dose increments including the specified motion and, for comparison, without motion. The motion-induced change in D99.5% for the prostate CTV (ΔD99.5%) and in D98% for the LN CTV (ΔD98%) was calculated using the final cumulative dose of each fraction and averaged over all imaged fractions. The real-time reconstructed dose distribution of DoseTracker was benchmarked against a clinical treatment planning system (TPS) and it was investigated whether the calculation speed was fast enough to keep up with the incoming data stream.

RESULTS

Translational motion was largest in cranio-caudal (CC) direction (prostate: [-5.9, +8.4] mm; LN: [-9.9; +11.0] mm) and anterior-posterior (AP) direction (prostate:[-5.6; +6.9] mm; LN: [-9.6; +11.0] mm). The pitch was the largest rotation (prostate: [-22.5; +25.2] deg; LN: [-3.9; +5.5] deg). The prostate CTV ΔD99.5% was [-16.2; +2.5]% for single fractions and [-3.0; +1.7]% when averaged over all imaged fractions. The LN CTV ΔD98% was [-19.8; +1.2]% for single fractions and [-3.1; +0.9]% after averaging. Mean (Standard deviation) absolute dose errors in DoseTracker of 107.8% (Std: 1.9%) for the prostate and 105.5% (Std:1.4%) for the LN were corrected during dose reconstruction by automatically calculated normalization factors. It resulted in accurate calculation of the motion-induced dose errors with relative differences between DoseTracker and TPS dose calculations of -0.1% (Std: 0.5%) (prostate CTV ΔD99.5%) and -0.2% (Std: 0.5%) (LN CTV ΔD98%). The DoseTracker calculation was fast enough to keep up with the incoming inputs for all but two out of 107 184 dose calculations.

CONCLUSION

Using the developed framework for dose perturbation monitoring, we found that the differential 6DoF target motion caused substantial dose perturbation for individual fractions, which largely averaged out after several fractions. The framework was shown to provide reliable dose calculations and a sufficiently high-dose reconstruction speed to be applicable in real-time.

French AFU Cancer Committee Guidelines - Update 2024-2026: Prostate cancer - Diagnosis and management of localised disease

OBJECTIVE

The aim of the Oncology Committee of the French Urology Association is to propose updated recommendations for the diagnosis and management of localized prostate cancer (PCa).

METHODS

A systematic review of the literature from 2022 to 2024 was conducted by the CCAFU on the elements of diagnosis and therapeutic management of localized PCa, evaluating references with their level of evidence.

RESULTS

The recommendations set out the genetics, epidemiology and diagnostic methods of PCa, as well as the concepts of screening and early detection. MRI, the reference imaging test for localized cancer, is recommended before prostate biopsies are performed. Molecular imaging is an option for disease staging. Performing biopsies via the transperineal route reduces the risk of infection. Active surveillance is the standard treatment for tumours with a low risk of progression. Therapeutic methods are described in detail, and recommended according to the clinical situation.

CONCLUSION

This update of French recommendations should help to improve the management of localized PCa.

Nodal radiotherapy for prostate adenocarcinoma recurrence: predictive factors for efficacy

Background

Nodes are the second site for prostate cancer recurrence. Whole-pelvic radiotherapy (WPRT) has shown superiority over nodal stereotactic body radiotherapy (SBRT) in two retrospective cohorts. We aimed to compare both modalities and assess factors associated with treatment outcomes.

Materials and methods

This retrospective multicentric cohort study included patients from five institutions spanning from 2010 to 2022. Patients had a history of prostatic adenocarcinoma classified as N0 M0 at diagnosis with a first nodal-only pelvic castration-sensitive recurrence. Failure-free survival (FFS) was defined as the time from the end of RT to the first failure event-biochemical or imaging recurrence, or death.

Results

A total of 147 patients (pts) were analyzed, mainly treated for a recurrence after initial prostatectomy (87%), with 64 (43.5%) undergoing SBRT and 83 (56.5%) undergoing WPRT. SBRT was chosen mainly for dosimetric constraints (67%) and was associated with a lower rate of concomitant androgen deprivation therapy (ADT) prescription. With a median follow-up of 68 months [inter-quartile range (IQR) = 51], FFS was significantly lower in the SBRT group (p < 0.0001). In multivariable analysis, WPRT and ADT were associated with a longer FFS. Factors associated with a longer FFS after SBRT included associated ADT, lower prostate-specific antigen (PSA) levels, a PSA doubling time >6 months, and a Gleason score <8. SBRT was associated with a lower rate of genitourinary and gastrointestinal grade ≥2 complications.

Discussion

For an isolated pelvic nodal prostate cancer recurrence, SBRT is associated with a shorter FFS compared to WPRT. SBRT is often more convenient for patients and leaves further pelvic salvage options available, so it can be explored as an option for well-informed patients.

A Phase 1 Trial of Image Guided Risk Volume-Adapted Postprostatectomy Radiation Therapy

PURPOSE

This was a phase 1 trial with the primary objective of identifying the most compressed dose schedule (DS) tolerable using risk volume-adapted, hypofractionated, postoperative radiation therapy (PORT) for biochemically recurrent prostate cancer. Secondary endpoints included biochemical progression-free survival and quality of life (QOL).

METHODS AND MATERIALS

Patients were treated with 1 of 3 isoeffective DSs (DS1: 20 fractions, DS2: 15 fractions, and DS3: 10 fractions) that escalated the dose to the imaging-defined local recurrence (73 Gy3 equivalent dose in 2Gy fractions) and de-escalated the dose to the remainder of the prostate bed (48 Gy3 equivalent dose in 2Gy fractions). Escalation followed a standard 3 + 3 design with a 6-patient expansion at the maximally tolerated hypofractionated DS. Dose-limiting toxicity was defined as Common Terminology Criteria for Adverse Events v.4.0 grade (G) 3 toxicity lasting >4 days within 21 days of PORT completion or G4 gastrointestinal (GI) or genitourinary toxicities thereafter. QOL was assessed longitudinally through 24 months with the Expanded Prostate Cancer Index Composite short form.

RESULTS

Between January 2018 and December 2023, 15 patients were treated (3 with DS1, 3 with DS2, and 9 with DS3). The median follow-up was 48 months. No dose-limiting toxicities were observed on any DS, and thus, expansion occurred at DS3. The cumulative incidence of G3 GI and genitourinary toxicity was 7% and 9% at 24 months, respectively, with no G4 events observed. Transient, acute G2+ GI toxicity was the most common. QOL worsened transiently during study follow-up in urinary incontinence, GI, and sexual subdomains but was similar to baseline by 24 months. The biochemical progression-free survival was 91% at both 24 and 60 months.

CONCLUSIONS

The maximally tolerated hypofractionated DS for hypofractionated, risk volume-adapted PORT was determined to be DS3 (36.4 Gy to the prostate bed and 47.1 Gy to the imaging-defined recurrence in 10 daily fractions). No >G3 events were observed. Transient declines in QOL did not persist through 24 months.

Whole pelvis vs. hemi pelvis elective nodal radiotherapy in patients with PSMA-positive nodal recurrence after radical prostatectomy - a retrospective multi-institutional propensity score analysis

PURPOSE

Despite growing evidence for bilateral pelvic radiotherapy (whole pelvis RT, WPRT) there is almost no data on unilateral RT (hemi pelvis RT, HPRT) in patients with nodal recurrent prostate cancer after prostatectomy. Nevertheless, in clinical practice HPRT is sometimes used with the intention to reduce side effects compared to WPRT. Prostate-specific membrane antigen positron emission tomography / computed tomography (PSMA-PET/CT) is currently the best imaging modality in this clinical situation. This analysis compares PSMA-PET/CT based WPRT and HPRT.

METHODS

A propensity score matching was performed in a multi-institutional retrospective dataset of 273 patients treated with pelvic RT due to nodal recurrence (214 WPRT, 59 HPRT). In total, 102 patients (51 in each group) were included in the final analysis. Biochemical recurrence-free survival (BRFS) defined as prostate specific antigen (PSA) < post-RT nadir + 0.2ng/ml, metastasis-free survival (MFS) and nodal recurrence-free survival (NRFS) were calculated using the Kaplan-Meier method and compared using the log rank test.

RESULTS

Median follow-up was 29 months. After propensity matching, both groups were mostly well balanced. However, in the WPRT group there were still significantly more patients with additional local recurrences and biochemical persistence after prostatectomy. There were no significant differences between both groups in BRFS (p = .97), MFS (p = .43) and NRFS (p = .43). After two years, BRFS, MFS and NRFS were 61%, 86% and 88% in the WPRT group and 57%, 90% and 82% in the HPRT group, respectively. Application of a boost to lymph node metastases, a higher RT dose to the lymphatic pathways (> 50 Gy EQD2α/β=1.5 Gy) and concomitant androgen deprivation therapy (ADT) were significantly associated with longer BRFS in uni- and multivariate analysis.

CONCLUSIONS

Overall, this analysis presents the outcome of HPRT in nodal recurrent prostate cancer patients and shows that it can result in a similar oncologic outcome compared to WPRT. Nevertheless, patients in the WPRT may have been at a higher risk for progression due to some persistent imbalances between the groups. Therefore, further research should prospectively evaluate which subgroups of patients are suitable for HPRT and if HPRT leads to a clinically significant reduction in toxicity.

Late Urinary Toxicity and Quality of Life With Pelvic Radiation Therapy for High-Risk Prostate Cancer: Dose-Effect Relations in the POP-RT Randomized Phase 3 Trial

PURPOSE

The POP-RT phase 3 randomized trial showed improved biochemical failure-free survival and metastasis-free survival with whole pelvic radiation therapy versus prostate-only radiation therapy for high and very high-risk prostate cancer, albeit with worse RTOG late urinary toxicity. We report updated late urinary adverse effects and bladder dose-effect relations within this trial.

METHODS AND MATERIALS

Late urinary toxicity and the cumulative severity of each symptom during the follow-up period were graded using the Common Terminology Criteria for Adverse Events (CTCAE), version 5.0. Bladder dosimetry in 5-Gy increments (V5, V10, V15, V65, V68Gy) in the approved radiation therapy plans was compared with urinary symptoms and overall grade 2+ toxicity. Potential factors influencing urinary toxicity were tested using multivariable logistic regression analysis. Updated urinary quality of life (QOL) scores were compared between the trial arms.

RESULTS

Complete combined data for late urinary symptoms and dosimetry was available for 193 of 224 patients. At a median follow-up of 75 months, cumulative late urinary CTCAE grade 3 toxicity was low and similar for whole pelvic radiation therapy and prostate-only radiation therapy (5.2% vs 4.1%, P = .49), and grade 2 toxicity was 31.3% versus 22.7%, respectively (P = .12). Cumulative rates of each urinary symptom were similar between both arms. Multivariable analysis with age at diagnosis, known diabetes, tumor stage, trial arm, prior transurethral resection of prostate, grade 2+ acute urinary toxicity, low bladder dose (V10Gy), and moderate bladder dose (V40Gy) did not identify any significant association with late urinary toxicity. Urinary QOL scores was similar between both the arms for all the symptoms.

CONCLUSIONS

During long-term follow-up, whole pelvic radiation therapy resulted in low (∼5%) and similar grade 3 cumulative urinary toxicity as prostate-only radiation therapy. The long-term patient-reported QOL scores were similar. No causative factors affecting the late urinary toxicity were identified.

Moderately hypofractionated prostate-only versus whole-pelvis radiotherapy for high-risk prostate cancer: A retrospective real-world single-center cohort study

Background

The benefit of prophylactic whole pelvis radiation therapy (WPRT) in prostate cancer has been debated for decades, with evidence based mainly on conventional fractionation targeting pelvic nodes.

Aim

This retrospective cohort study aimed to explore the impact of adding moderately hypofractionated pelvic radiotherapy to prostate-only irradiation (PORT) on prognosis, toxicity, and quality of life in real-world settings.

Materials and methods

Patients with high-risk and conventionally staged prostate cancer (cT1-3N0M0) treated with moderately hypofractionated WPRT or PORT, using external beam radiotherapy alone or combined with high-dose-rate brachytherapy, at Örebro University Hospital between 2008 and 2021 were identified. Biochemical failure-free survival (BFFS), metastasis-free survival (MFS), prostate cancer-specific survival (PCSS), and overall survival (OS) were compared using Kaplan-Meier method and Cox proportional hazards. Toxicity and quality of life measures were also analysed.

Results

Among 516 patients (227 PORT, 289 WPRT), 5-year BFFS rates were 77 % (PORT) and 74 % (WPRT), adjusted HR=1.50 (95 % CI=0.88-2.55). No significant differences were found in MFS, PCSS, or OS in main analyses. WPRT was associated with a higher risk of acute grade ≥ 2 and 3 genitourinary toxicities whereas no differences in late toxicities or quality of life between PORT and WPRT were observed.

Conclusion

We found no significant differences in oncological outcomes or quality of life when comparing moderately hypofractionated PORT to WPRT. Some differences in toxicity patterns were observed. Despite caveats related to study design, our findings support the need for further research on WPRT's impact on treatment-related and patient-reported outcomes.

Volumetric Modulated Arc Therapy for High-Risk and Very High-Risk Locoregional Prostate Cancer in the Modern Era: Real-World Experience from an Asian Cohort

This study retrospectively evaluates the clinical outcomes of definitive volumetric modulated arc therapy (VMAT) for high-risk or very high-risk locoregional prostate cancer patients from an Asian institution. Consecutive patients who received VMAT (76 Gy in 38 fractions) between January 2017 and June 2022 were included. Whole pelvic radiotherapy (WPRT) (46 Gy in 23 fractions) was employed for clinically node-negative disease (cN0) and a Roach estimated risk of ≥15%, as well as simultaneous integrated boost (SIB) of 55-57.5 Gy to node-positive (cN1) disease. The primary endpoint was biochemical relapse-free survival (BRFS). Secondary endpoints included radiographic relapse-free survival (RRFS), metastasis-free survival (MFS) and prostate cancer-specific survival (PCSS). A total of 209 patients were identified. After a median follow-up of 47.5 months, the 4-year actuarial BRFS, RRFS, MFS and PCSS were 85.2%, 96.8%, 96.8% and 100%, respectively. The incidence of late grade ≥ 2 genitourinary (GU) and gastrointestinal (GI) toxicity were 15.8% and 11.0%, respectively. No significant difference in cancer outcomes or toxicity was observed between WPRT and prostate-only radiotherapy for cN0 patients. SIB to the involved nodes did not result in increased toxicity. International Society of Urological Pathology (ISUP) group 5 and cN1 stage were associated with worse RRFS (p < 0.05). PSMA PET-CT compared to conventional imaging staging was associated with better BRFS in patients with ISUP grade group 5 (p = 0.039). Five-year local experience demonstrates excellent clinical outcomes. PSMA PET-CT staging for high-grade disease and tailored pelvic irradiation based on nodal risk should be considered to maximize clinical benefit.

[Short- and medium-term tolerance of hypofractionated prostate radiotherapy with simultaneous integrated boost]

PURPOSE

This retrospective study was conducted to ensure that irradiation of the pelvic lymph node areas associated with simultaneous hypofractionated boost to the prostate according to the protocol implemented at the university hospital of Tours (France) does not result in excess urinary and digestive toxicity in the short and medium term.

MATERIALS AND METHODS

The study population included patients with localized unfavourable intermediate or high-risk prostate cancer. The dose delivered was 65Gy in 25 fractions of 2.6Gy to the prostate and seminal vesicles, and 50Gy in 25 fractions of 2Gy to the pelvic lymph nodes. Acute toxicity events (between the start of radiotherapy and the first follow-up consultation) and medium-term toxicity events (after the first follow-up consultation) were assessed using the CTCAE version 5.0 classification.

RESULTS

Sixty-three patients were treated according to the protocol between January 1st, 2020, and October 31st, 2022. The majority of them had high-risk prostate cancer (79%). The median follow-up was 15 months. Very few patients reported grade 3-4 toxicity acutely (6% urinary and 0% digestive toxicity) or in the medium term (7% urinary and 0% and digestive toxicity).

CONCLUSION

Radiotherapy of pelvic lymph node areas with simultaneous hypofractionated boost to the prostate is feasible, with low rates of severe acute and medium-term toxicity.

Elective Pelvic Lymph Node Radiation Therapy and the Risk of Death in Patients With Unfavorable-Risk Prostate Cancer: A Postrandomization Analysis

PURPOSE

Although a contemporary randomized clinical trial has led to the use of whole-pelvic radiation therapy (WPRT), long-term data evaluating a potential reduction in mortality are lacking and are addressed in the current study.

MATERIALS AND METHODS

From 2005 to 2015, 350 men with localized, unfavorable-risk prostate cancer (PC) were randomly assigned to receive androgen deprivation therapy (ADT) and RT plus docetaxel versus ADT and RT. Treatment of the pelvic lymph nodes was at the discretion of the treating physician. Multivariable Cox and Fine and Grays regression analyses were performed to assess whether a significant association existed between radiation treatment volume and all-cause mortality (ACM) and PC-specific mortality (PCSM), respectively, adjusting for known PC prognostic factors and comorbidity. An interaction term between age (categorized by dichotomization at 65 years to enable clinical interpretation and applicability of the results and which approximates the median (66 years [IQR, 61-70]) and radiation treatment volume was included in the analysis.

RESULTS

After a median follow-up of 10.20 years (IQR, 7.96-11.41), 89 men died (25.43%); of these, 42 died of PC (47.19%). Of the 350 randomly assigned patients, 88 (25.14%) received WPRT. In men younger than 65 years, WPRT was associated with a significantly lower ACM risk (adjusted hazard ratio [AHR], 0.33 [95% CI, 0.11 to 0.97]; P = .04) and lower PCSM risk (AHR, 0.17 [95% CI, 0.02 to 1.35]; P = .09) after adjusting for covariates, whereas this was not the case for men 65 years or older.

CONCLUSION

WPRT has the potential to reduce mortality in younger men with unfavorable-risk PC.

Patterns of Failure After Prostate-Only Radiotherapy in High-Risk Prostate Cancer: Implications for Refining Pelvic Nodal Contouring Guidelines

PURPOSE

To study prostate specific membrane antigen - positron emission tomography (Ga68PSMA-PETCT) based patterns of relapse at biochemical failure (BCF) after prostate-only radiotherapy (PORT) in high-risk (HR) prostate cancer and its implications on pelvic contouring recommendations.

METHODS AND MATERIALS

Patients with clinico-radiological high-risk node-negative prostate cancer treated with curative PORT and androgen deprivation therapy (ADT), either within the POP-RT randomised trial or off trial, who underwent a Ga68PSMA-PETCT upon BCF were included. Patterns of regional and distant recurrence on Ga68PSMA-PETCT were studied. Pelvic nodal recurrences were mapped with reference to the superior border of pubic symphysis. Pelvic lymph nodal caudal border (PLNcb) recommendations in the published contouring guidelines (RTOGcb, GETUGcb, PIVOTALcb, NRGcb, GFRUcb) were evaluated.

RESULTS

Of the total 262 patients screened, 68 eligible patients were included (POP-RT trial 35 patients; off-trial 33 patients). Median follow-up was 91 months (IQR, 72-117) and median time to BCF was 65 months (IQR, 49-83). Regional and distant recurrence was seen in 31 (46%) and 31 (46%) patients, respectively. Of the nodal recurrences, nearly half (46%, 14/31) had no distant metastases and 64% (20/31) had a failure in the common iliac nodal region. The lower-most nodal recurrence was 20 mm cranial to the top of pubic symphysis (RTOGcb, GETUGcb, GFRUcb) and 10 mm cranial to the PIVOTALcb. The PLNcb recommended by NRG guideline (NRGcb) had an inter-patient variability of 32 mm, ranging from 16 mm above to 16 mm below the top of pubic symphysis, and the lower most nodal recurrence ranged from 4 mm to 36 mm cranial to NRGcb.

CONCLUSION

Pelvic failures accounted for a major proportion of recurrences after prostate-only radiotherapy, with the caudal most nodal recurrence being 20 mm cranial to the top of pubic symphysis. This could have implications in defining the caudal border of contouring recommendations.

Is Ultrahypofractionated Whole Pelvis Radiation Therapy (WPRT) as Well Tolerated as Conventionally Fractionated WPRT in Patients With Prostate Cancer? Early Results From the HOPE Trial

OBJECTIVE

The aim of this work was to evaluate the acute toxicity and quality-of-life (QOL) impact of ultrahypofractionated whole pelvis radiation therapy (WPRT) compared with conventional WPRT fractionation after high-dose-rate prostate brachytherapy (HDR-BT).

METHODS AND MATERIALS

The HOPE trial is a phase 2, multi-institutional randomized controlled trial of men with prostate-confined disease and National Comprehensive Cancer Network unfavorable intermediate-, high-, or very-high-risk prostate cancer. Patients were randomly assigned to receive conventionally fractionated WPRT (standard arm) or ultrahypofractionated WPRT (experimental arm) in a 1:1 ratio. All patients underwent radiation therapy with 15 Gy HDR-BT boost in a single fraction followed by WPRT delivered with conventional fractionation (45 Gy in 25 daily fractions or 46 Gy in 23 fractions) or ultrahypofractionation (25 Gy in 5 fractions delivered on alternate days). Acute toxicities measured during radiation therapy and at 6 weeks posttreatment were assessed using the clinician-reported Common Terminology Criteria for Adverse Events version 5.0, and QOL was measured using the Expanded Prostate Cancer Index Composite (EPIC-50) and International Prostate Symptom Score (IPSS).

RESULTS

A total of 80 patients were enrolled and treated across 3 Canadian institutions, of whom 39 and 41 patients received external radiation therapy with conventionally fractionated and ultrahypofractionated WPRT, respectively. All patients received androgen deprivation therapy except for 2 patients treated in the ultrahypofractionated arm. The baseline clinical characteristics of the 2 arms were similar, with 51 (63.8%) patients having high or very-high-risk prostate cancer disease. Treatment was well tolerated with no significant differences in the rate of acute adverse events between arms. No grade 4 adverse events or treatment-related deaths were reported. Ultrahypofractionated WPRT had a less detrimental impact on the EPIC-50 bowel total, function, and bother domain scores compared with conventional WPRT in the acute setting. By contrast, more patients treated with ultrahypofractionated WPRT reached the minimum clinical important difference on the EPIC-50 urinary domains. No significant QOL differences between arms were noted in the sexual and hormonal domains.

CONCLUSIONS

Ultrahypofractionated WPRT after HDR-BT is a well-tolerated treatment strategy in the acute setting that has less detrimental impact on bowel QOL domains compared with conventional WPRT.

Long-Term Quality-of-Life Outcomes After Prostate Radiation Therapy With or Without High-Dose-Rate Brachytherapy Boost: Post Hoc Analysis of TROG 03.04 RADAR

PURPOSE

Adding high-dose-rate brachytherapy (BT) boost to external beam radiation therapy (EBRT) improves biochemical control but may affect patient-reported quality of life (QOL). We sought to determine long-term QOL outcomes for EBRT+BT versus EBRT alone.

METHODS AND MATERIALS

This was a post hoc analysis of the Trans-Tasman Radiation Oncology Group 03.04 Randomized Androgen Deprivation and Radiotherapy (TROG 03.04 RADAR) trial. Only patients who received 74 Gy conventionally fractionated EBRT (n = 260) or 46 Gy conventionally fractionated EBRT plus 19.5 Gy in 3 fractions high-dose-rate BT boost (n = 237) were included in this analysis. The primary endpoint was patient-reported QOL measured using the European Organisation for Research and Treatment of Cancer QOL (EORTC QLQ-C30) and prostate-specific QOL module (EORTC QLQ-PR25) questionnaires. We evaluated temporal changes in QOL scores, rates of symptom resolution, and the proportion of men who had decrements from baseline of >2 × the threshold for minimal clinically important change (2 × MCIC) for each domain.

RESULTS

At 5, 17, and 29 months after radiation therapy, the EBRT+BT group had 2.5 times (95% confidence interval [CI], 1.4-4.2; P < .001), 2.9 times (95% CI, 1.7-4.9; P < .001), and 2.6 times (95% CI, 1.4-4.6; P = .002) greater odds of reporting 2 × MCIC in urinary QOL score compared with EBRT. There were no differences beyond 29 months. EBRT+BT led to a slower rate of urinary QOL symptom score resolution up to 17 months after radiation therapy compared with EBRT (P < .001) but not at later intervals. In contrast, at the end of the radiation therapy period and at 53 months after radiation therapy, the EBRT+BT group had 0.65 times (95% CI, 0.44-0.96; P = .03) and 0.51 times (95% CI, 0.32-0.79; P = .003) the odds of reporting 2 × MCIC in bowel QOL symptom scores compared with EBRT. There were no significant differences in the rate of bowel QOL score resolution. There were no significant differences in global health status or sexual activity scores between the 2 groups.

CONCLUSIONS

There were no persistent differences in patient-reported QOL measures between EBRT alone and EBRT+BT. BT boost does not appear to negatively affect long-term, patient-reported QOL.

Ultrahypofractionated Radiation Therapy for Prostate Cancer Including Seminal Vesicles in the Target Volume: A Treatment-planning Study Based on the HYPO-RT-PC Fractionation Schedule

Purpose

Ultrahypofractionated (UHF) radiation therapy (RT) has become a treatment alternative for patients with localized prostate cancer. In more advanced cases, seminal vesicles (SVs) are routinely included in the target volume. The Scandinavian HYPO-RT-PC trial, which compared 42.7 Gy in 7 fractions (fr) to conventional fractionation (CF), did not include SVs in the clinical target volume. The primary objective of the present work was to implement a ultrahypofractionated-simultaneous integrated boost (UHF-SIB) for prostate cancer RT, incorporating SVs into the target volume based on this fractionation schedule. A secondary objective was to analyze the unintentional dose coverage of SVs from state-of-the-art volumetric modulated arc therapy treatments to the prostate gland only.

Methods and Materials

Two different equieffective UHF-SIB treatment schedules to SVs were derived based on the CF clinical schedule (50.0 Gy/25 fr to elective SVs and 70.0 Gy/35 fr to verified SV-invasion (SVI)) using the linear quadric model with α/β = 2 Gy and 3 Gy. The dose to the prostate was 42.7 Gy/7 fr in both schedules, with 31.2 Gy/37.8 Gy (α/β = 2 Gy) and 32.7 Gy/40.1 Gy (α/β = 3 Gy) to elective SV/verified SVI. Volumetric modulated arc therapy plans to the proximal 10 mm and 20 mm were optimized, and dose-volume metrics for target volumes and organs at risk were evaluated.

Results

Dose metrics were overall lower for UHF-SIB compared with CF. QUANTEC-based volume criteria were 2% to 7% lower for the rectum and 2% to 4% lower for the bladder in the UHF-SIB. The D98% to elective SV was 7 to 12 Gy3 lower with UHF-SIB, and the corresponding data for verified SVI were approximately 2 to 3 Gy3. The SV(10 mm) V90%/(29.5 Gy) for prostate-only treatments (42.7 Gy) were as follows: median (IQR), 99% (87-100) and 78% (58-99) for the clinical target volume and planning target volume, respectively.

Conclusions

UHF RT based on the HYPO-RT-PC fractionation schedule, with a SIB technique, to the prostate and the base of the SV can be planned with lower doses (EQD2) to organs at risk, compared with CF. The unintentional dose to the proximal parts of SVs in prostate-only treatment can be substantial.