The Impact of Definitive Local Therapy for Lymph Node-Positive Prostate Cancer: A Population-Based Study

Prognostic impact of prostate-specific membrane antigen positron emission tomography (PSMA PET) staging for clinically node-positive prostate cancer

INTRODUCTION

In the current American Joint Committee on Cancer staging system, patients with pelvic nodal metastases are considered stage IV prostate cancer. This study aims to investigate whether men with prostate-specific membrane antigen positron emission tomography (PSMA PET)-detected pelvic node-positive prostate cancer at diagnosis have a better outcome compared to men with node-positive disease identified on conventional imaging.

METHODS

This is a retrospective cohort study comparing the outcomes of men with node-positive prostate cancer and disease confined to the pelvis, staged with conventional versus PSMA PET imaging. Men had to be treated definitively with a combination of androgen deprivation therapy and radiation treatment to the prostate and pelvic lymph nodes. Kaplan-Meier and Cox regression analysis was used to compare biochemical failure-free survival (BFFS) and overall survival (OS).

RESULTS

Seventy-six men with nodal metastases confined to the pelvis were identified. Fifty-one were detected with PSMA PET while 25 were staged with conventional imaging. PSMA PET staged patients had a lower proportion of Gleason 8-10 disease (78% vs. 96%) as well as a lower median prostate-specific antigen (11 ng/mL vs. 26 ng/mL). BFFS at 4 years was 72% with PSMA PET-detected node-positive disease vs. 38% with conventionally detected node-positive disease. Four-year OS was 93% with PSMA PET staged patients vs. 76% with conventionally staged patients. On multivariate analysis, the PSMA PET staged group was associated with improved BFFS (Adjusted HR = 3.00, 95% CI 1.43, 6.29, P = 0.004) and OS (Adjusted HR = 5.81, 95% CI 1.43, 23.7, P = 0.007).

CONCLUSION

Men with PSMA PET-detected node-positive prostate cancer confined to the pelvis have significantly better biochemical control and survival compared to those with node-positive pelvic disease identified through conventional staging.

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.

Evaluation of Treatment Outcomes of Prostate Cancer Patients With Lymph Node Metastasis Treated With Definitive Radiotherapy: Comparative Analysis of PSMA PET/CT and Conventional Imaging

PURPOSE

We investigated the impact of prostate-specific membrane antigen (PSMA) PET/CT compared with conventional imaging on treatment outcomes for node-positive prostate cancer (PCa) patients who underwent androgen deprivation therapy (ADT) and external radiotherapy (RT).

PATIENTS AND METHODS

A multicentric, retrospective study recruited patients with node-positive PCa patients who underwent conventional radiological evaluation or PSMA PET/CT and received ADT and RT at 3 hospitals from 2009 to 2021 were enrolled. Patients underwent prostate and pelvis RT, accompanied by a minimum of 6 months of ADT. The primary endpoints were progression-free survival (PFS) and PCa-specific survival (PCSS). Cox regression analyzed the association of survival with potential prognostic factors, whereas logistic regression identified the predictors of bone and lymph node metastasis.

RESULTS

The median follow-up time was 64.0 months. The majority of patients (64.1%) underwent PSMA PET/CT for staging. The 5-year rates of PFS and PCSS were 63.7% and 83.7%, respectively. Disease progression was observed in 90 patients (36.3%). In multivariable analysis, ADT duration of less than 24 months and post-RT prostate-specific antigen (PSA) nadir were prognostic for PFS. Early clinical T stage and PSMA PET/CT predicted better PCSS. Patients staged with PSMA PET/CT had exhibited significantly higher 5-year PCSS rates than compared with those staged with conventional imaging (95.1% vs 76.9%; P = 0.01). Shorter ADT duration and higher PSA levels after RT independently predicted bone metastasis in multivariable logistic regression. Advanced T stage, shorter ADT duration, and higher PSA levels after neoadjuvant ADT predicted nonregional lymph node recurrence.

CONCLUSIONS

ADT with pelvis RT is an effective treatment option for node-positive PCa patients. The PSMA PET/CT outperformed conventional imaging in PCSS, emphasizing the importance of precise clinical staging for patients undergoing definitive RT.

Hypofractionated radiation therapy combined with androgen deprivation therapy for clinically node-positive prostate cancer

PURPOSE

This study aimed to analyze the treatment outcomes of combined definitive radiation therapy (RT) and androgen deprivation therapy (ADT) for clinically node-positive prostate cancer.

MATERIALS AND METHODS

Medical records of 60 patients with clinically suspected metastatic lymph nodes on radiological examination were retrospectively analyzed. Eight patients (13.3%) were suspected to have metastatic common iliac or para-aortic lymph nodes. All patients underwent definitive RT with a dose fractionation of 70 Gy in 28 fractions. ADT was initiated 2-3 months before RT and continued for at least 2 years. Biochemical failure rate (BFR), clinical failure rate (CFR), overall survival (OS), and prostate cancer-specific survival (PCSS) were calculated, and genitourinary and gastrointestinal adverse events were recorded.

RESULTS

The median follow-up period was 5.47 years. The 5-year BFR, CFR, OS, and PCSS rates were 19.1%, 11.3%, 89.0%, and 98.2%, respectively. The median duration of ADT was 2.30 years. BFR and CFR increased after 3 years, and 11 out of 14 biochemical failures occurred after the cessation of ADT. Grade 2 and beyond late genitourinary and gastrointestinal toxicity rates were 5.0% and 13.3%, respectively. However, only two grade 3 adverse events were reported, and no grade 4-5 adverse events were reported. Patients with non-regional lymph node metastases did not have worse BFR, CFR, or adverse event rates.

CONCLUSION

This study reported the efficacy and tolerable toxicity of hypofractionated definitive RT combined with ADT for clinically node-positive prostate cancer. Additionally, selected patients with adjacent non-regional lymph node metastases might be able to undergo definitive RT combined with ADT.

Local Therapy on Clinically Lymph Node-positive Prostate Cancer: A Systematic Review and Meta-analysis

CONTEXT

Patients with clinically lymph node-positive (cN1) prostate cancer (PCa) are traditionally regarded to have metastatic disease, and the role of local therapy (LT) in their treatment remains unclear.

OBJECTIVE

To evaluate the outcomes of cN1 PCa patients treated with LT, and secondarily to compare between different modalities of LT, including radiotherapy (RT) and radical prostatectomy (RP).

EVIDENCE ACQUISITION

A bibliographic search was performed using Medline, Embase, and the Cochrane Library to identify studies comparing the survival outcomes of cN1 PCa patients treated with LT (RT or RP) with those who did not receive any form of LT (observation or androgen deprivation therapy alone). The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) recommendations were followed. Survival outcomes of the addition of LT were assessed using a random-effect model.

EVIDENCE SYNTHESIS

A total of 8522 patients across eight studies were included. LT significantly improved overall survival (OS) across all time points from 2 to 10 yr compared with patients without LT, most notably providing a durable benefit in 10-yr OS (odds ratio [OR]: 1.49, 95% confidence interval [CI] 1.06-2.10). Both RT and RP were associated with benefits to both OS and recurrence-free survival, with no significant difference in OS between both modalities in medium-term follow-up (4-yr OR: 0.76, 95% CI 0.41-1.40, p = 0.19).

CONCLUSIONS

Regardless of modality, the use of LT in cN1 patients improved OS. Future studies should aim to identify patients who could benefit from LT and include more comprehensive survival data including biochemical recurrence.

PATIENT SUMMARY

In this study, we evaluated the outcomes of clinically lymph node-positive (cN1) prostate cancer (PCa) patients treated with local therapy (LT) and compared between different modalities of LT, including radiotherapy (RT) and radical prostatectomy (RP). We found that the addition of LT for cN1 PCa patients leads to a significant improvement in survival outcomes, most notably for overall survival, with no significant difference between RT and RP.

Androgen deprivation alone versus combined with pelvic radiation for adverse events and quality of life in clinically node-positive prostate cancer

The COHORT trial was conducted to compare the efficacy of androgen deprivation therapy (ADT) alone versus combined with radiation therapy (ADT + RT) for clinically node-positive prostate cancer. We reported adverse events and quality of life between the two treatment groups. Fifty-nine patients were randomized to receive ADT alone or ADT + RT and analyzed as per-protocol. Patients allocated to the ADT alone arm received ADT for at least 2 years. Patients in the ADT + RT arm received additional pelvic RT. Higher rates of grade ≥ 2 acute genitourinary (0% vs. 7.1%) and late gastrointestinal adverse events (0% vs. 14.3%) were reported in the ADT + RT arm compared with the ADT alone. However, grade ≥ 2 late genitourinary toxicity was more common in the ADT alone than the ADT + RT arm (9.7% vs. 3.6%). No grade ≥ 3 adverse events were reported. There was no statistically significant difference in EPIC scores between two treatment arms. However, the urinary and bowel domains tended to decrease and recover in the ADT + RT arm. In conclusion, ADT + RT demonstrated higher rates of adverse events compared to ADT alone. However, the addition of RT did not significantly impact the quality of life.

Immediate radiotherapy versus observation in patients with node-positive prostate cancer after radical prostatectomy

BACKGROUND

The optimal management of node-positive (pN1) prostate cancer following radical prostatectomy (RP) remains uncertain. Despite randomized evidence, utilization of immediate, life-long androgen deprivation therapy (ADT) remains poor, and recent trials of early salvage radiotherapy included only a minority of pN1 patients. We therefore emulated a hypothetical pragmatic trial of adjuvant radiotherapy versus observation in men with pN1 prostate cancer.

METHODS

Using the RADICALS-RT trial to inform the design of a hypothetical trial, we identified men aged 50-69 years with pT2-3 Rany pN1 M0, pre-treatment PSA < 50 ng/mL prostate cancer in the NCDB from 2006 to 2015 treated with 60-72 Gy of adjuvant RT (aRT) ± ADT within 26 weeks of RP or observation. After estimating a propensity score for receipt of aRT, we estimated absolute and relative treatment effects using stabilized inverse probability of treatment (sIPW) re-weighting.

RESULTS

In total, 3510 patients were included in the study, of whom 587 (17%) received aRT (73% with concurrent ADT). Median follow-up was 40.0 -months, during which 333 deaths occurred. After sIPW re-weighting, baseline characteristics were well-balanced. Adjusted overall survival (OS) was 93% versus 89% at 5-years and 82% versus 79% at 7-years for aRT versus observation (p = 0.11). In IPW-reweighted Cox regression, aRT was associated with a lower risk of all-cause mortality (ACM) than observation, but this did not reach statistical significance (HR 0.70 p = 0.06). In analyses examining heterogeneity of treatment effects, aRT was associated with improved ACM only for men with Gleason 8-10 disease (HR 0.59, p = 0.01), ≥2 positive LNs (HR 0.49, p = 0.04 for 2 positive LNs; HR 0.42, p = 0.01 for ≥3 positive LNs), or negative surgical margins (HR 0.50, p = 0.02).

CONCLUSIONS

In observational analyses designed to emulate a hypothetical target trial of aRT versus observation in pN1 prostate cancer, aRT was associated with improved OS only for men with Gleason 8-10 disease, ≥2 positive LNs, or negative surgical margins.

Impact of prostate radiotherapy on survival outcomes in clinically node-positive prostate cancer: A multicentre retrospective analysis

PURPOSE

To evaluate clinical outcomes for cN1M0 prostate cancer treated with varied modalities.

MATERIALS AND METHODS

Men with radiological stage cN1M0 prostate cancer on conventional imaging, treated from 2011-2019 with various modalities across four centres in the UK were included. Demographics, tumour grade and stage, and treatment details were collected. Biochemical and radiological progression-free survival (bPFS, rPFS) and overall survival (OS) were estimated using Kaplan Meier analyses. Potential factors impacting survival were tested with univariable log-rank test and multivariable Cox-proportional hazards model.

RESULTS

Total 337 men with cN1M0 prostate cancer were included, 47% having Gleason grade group 5 disease. Treatment modalities included androgen deprivation therapy (ADT) in 98.9% men, either alone (19%) or in combinations including prostate radiotherapy (70%), pelvic nodal radiotherapy (38%), docetaxel (22%), or surgery (7%). At median follow up of 50 months, 5-year bPFS, rPFS, and OS were 62.7%, 71.0%, and 75.8% respectively. Prostate radiotherapy was associated with significantly higher bPFS (74.1% vs 34.2%), rPFS (80.7% vs 44.3%) and OS (86.7% vs 56.2%) at five years (log rank p < 0.001 each). On multivariable analysis including age, Gleason grade group, tumour stage, ADT duration, docetaxel, and nodal radiotherapy, benefit of prostate radiotherapy persisted for bPFS [HR 0.33 (95% CI 0.18-0.62)], rPFS [HR 0.25 (0.12-0.51)], and OS [HR 0.27 (0.13-0.58)] (p < 0.001 each). Impact of nodal radiotherapy or docetaxel was not established due to small subgroups.

CONCLUSION

Addition of prostate radiotherapy to ADT in cN1M0 prostate cancer yielded improved disease control and overall survival independent of other tumour and treatment factors.

Management of Pathologic Node-Positive Prostate Cancer following Radical Prostatectomy

PURPOSE OF REVIEW

Approximately 15% of prostate cancer patients have lymph node metastases at the time of radical prostatectomy (RP). However, there is no universally accepted standard of care for these men. The options for treatment in this subset of patients range from observation to a combination of adjuvant androgen deprivation therapy (aADT) and radiation therapy (RT).

RECENT FINDINGS

A recent systematic review showed that there was no clear choice out of the options above to treat these patients. Studies have shown that patients treated with adjuvant radiation therapy have lower all-cause mortality when compared to patients treated with salvage radiation therapy. In this review, we summarize treatment options for pathologic node-positive (pN1) patients and discuss the urgent need for robust clinical trials that includes observation as the control group to help establish a standard of care for treating patients with node-positive prostate cancer after RP.

Treating Primary Node-Positive Prostate Cancer: A Scoping Review of Available Treatment Options

There is currently no consensus on the optimal treatment for patients with a primary diagnosis of clinically and pathologically node-positive (cN1M0 and pN1M0) hormone-sensitive prostate cancer (PCa). The treatment paradigm has shifted as research has shown that these patients could benefit from intensified treatment and are potentially curable. This scoping review provides an overview of available treatments for men with primary-diagnosed cN1M0 and pN1M0 PCa. A search was conducted on Medline for studies published between 2002 and 2022 that reported on treatment and outcomes among patients with cN1M0 and pN1M0 PCa. In total, twenty-seven eligible articles were included in this analysis: six randomised controlled trials, one systematic review, and twenty retrospective/observational studies. For cN1M0 PCa patients, the best-established treatment option is a combination of androgen deprivation therapy (ADT) and external beam radiotherapy (EBRT) applied to both the prostate and lymph nodes. Based on most recent studies, treatment intensification can be beneficial, but more randomised studies are needed. For pN1M0 PCa patients, adjuvant or early salvage treatments based on risk stratification determined by factors such as Gleason score, tumour stage, number of positive lymph nodes, and surgical margins appear to be the best-established treatment options. These treatments include close monitoring and adjuvant treatment with ADT and/or EBRT.

Prostate and metastasis-directed focal therapy in prostate cancer: hype or hope?

INTRODUCTION

The paradigm of focal therapy's role in metastatic patients is being challenged by evolving attitudes and emerging data. At the current time, specifically regarding prostate cancer, does the evidence indicate this is more hype or hope?

AREAS COVERED

We searched the literature via PubMed, MEDLINE, and Embase for studies from 2014 to the present addressing focal therapy with non-palliative intent in metastatic prostate cancer patients, emphasizing prospective trials when available. We sought to address all common clinical scenarios: de novo synchronous diagnosis, oligorecurrence, oligoprogression, and mCRPC disease.

EXPERT OPINION

Current evidence is strongest, and in our opinion practice-changing, for prostate-directed RT in de novo metastatic patients with low metastatic burden. Metastasis-directed therapy with SBRT is consistently shown to have low rates of toxicity, and promising rates of ADT-free survival and progression-free survival. These can be utilized on a patient-by-patient basis with these endpoints in mind, but do not yet show sufficient benefit to be standard of care. This is a rich area of ongoing research, and many trials should publish in the coming years to shed light on many unanswered questions, including the role of cytoreductive prostatectomy, systemic therapy combined with MDT, and the integration of modern PET imaging.

Ten‐year outcomes of whole‐pelvic intensity‐modulated radiation therapy for prostate cancer with regional lymph node metastasis

BACKGROUND

Management of pelvic node-positive prostate cancer has been challenging and controversial. We conducted a study to evaluate the outcomes of whole-pelvic (WP) simultaneous integrated boost (SIB) intensity-modulated radiation therapy (IMRT) combined with androgen deprivation therapy (ADT).

METHODS

A total of 67 consecutive patients with cT1c-4N1M0 prostate cancer were definitively treated by WP SIB-IMRT. Neoadjuvant ADT (median: 8.3 months) was administered in all cases. WP SIB-IMRT was designed to simultaneously deliver 78, 66.3, and 58.5 Gy in 39 fractions to the prostate plus seminal vesicles, metastatic lymph nodes (LNs), and the pelvic LN region, respectively. Adjuvant ADT (median: 24.7 months) was administered in 66 patients.

RESULTS

The median follow-up period was 81.6 months (range: 30.5-160.7). Biochemical relapse-free, overall, and prostate cancer-specific survival rates at 10 years were 59.8%, 79.6%, and 86.3%, respectively. Loco-regional recurrence was not observed. Being in International Society of Urological Pathology grade group 5 and having a posttreatment detectable nadir prostate-specific antigen (PSA) level (≥0.010 ng/ml) were significantly associated with worse prostate cancer-specific survival and progression of castration resistance. The 10-year cumulative incidence rates of grade 2 and 3 late toxicities were, respectively, 1.5% and 0% for genitourinary, 0% and 1.5% for gastrointestinal events. No grade 4 acute or late toxicities were observed.

CONCLUSIONS

WP SIB-IMRT can be safely administered to patients with pelvic node-positive prostate cancer. Since grade group 5 and detectable nadir PSA levels are risks for castration resistance, we may need to increase the intensity of treatment for such cases.

Evaluation of the role of local therapy in patients with cN1M0 prostate cancer: A population-based study from the SEER database

Objective

To investigate the prognostic value of local therapy (LT) in cN1M0 prostate cancer (PCa).

Methods

Patients diagnosed with cN1M0 PCa were extracted from the surveillance, epidemiology, and end results (SEER) database. Kaplan-Meier (KM) curve was used to compare the survival outcomes between patients treated with and without LT. Further, among patients receiving LT, KM analysis was also applied to investigate the survival differences in patients with radical prostatectomy (RP) and radiation therapy (RT). Propensity score matching (PSM) analysis was performed to balance the basic characteristics of patients in each group and make it comparable when exploring the survival impact of different treatment types. Finally, uni- and multivariable Cox proportional-hazards models were utilized to identify independent prognostic factors associated with overall survival (OS) and cancer-specific survival (CSS) in this population.

Results

Patients treated with LT had significantly better OS (P<0.0001) and CSS (P<0.0001) than those without LT, as well as in most subgroups, except for non-White patients, or those with ISUP grade group 1 or T3 stage. Notably, patients receiving RP also had significantly better OS (P=0.00012) and CSS (P=0.0045) than those treated with RT alone, especially in those aged ≥75 years old, prostate-specific antigen (PSA) 10-20 ng/mL, ISUP grade 1-3 or non-white patients. Finally, clinical T stage, ISUP grade group and the administration of LT were identified to be independent prognostic factors for OS and CSS among cN1M0 PCa patients.

Conclusion

The cN1M0 PCa patients treated with LT were associated with significantly better survival. Among patients receiving LT, the combination of RP and PLND could lead to a better prognosis compared to RT alone in most subgroups. An individualized treatment strategy is warranted to be developed after weighing the benefits and risks of treatment.

Common iliac node positive prostate cancer treated with curative radiotherapy: N1 or M1a?

PURPOSE

Common iliac (CI) nodes are staged as (oligo)metastatic M1a for prostate cancer. It is unclear if outcomes of pelvic node-positive (cN1) differ from CI node-positive (CI-M1a) prostate cancer after curative treatment. Present study compares outcomes in these patients treated with radical whole pelvic radiotherapy and long-term ADT.

MATERIALS AND METHODS

Patients with node positive adenocarcinoma prostate were identified, either CI-M1a or cN1, from a prospectively maintained database. Over 75% of these patients were staged with Ga68PSMA-PETCT at diagnosis. All patients received long-term ADT and moderately or extremely hypofractionated radiotherapy to the prostate and pelvis including the CI region. At biochemical failure (BCF), restaging was done with Ga68PSMA-PETCT to establish the patterns of failure. CI-M1a cohort was classified as proximal or distal CI nodal location and studied for outcomes.

RESULTS

Of the 130 patients analyzed, 87 had cN1 and 43 had CI-M1a stage. Median duration of ADT before RT was 7 months and total duration was atleast 24 months. Majority (65%) had Gleason grade group IV-V while 75% had ≥T3 disease. After a median FU of 61 months, BCF in the 2 groups were similar, cN1, 21/87 (24.1%); CI-M1a, 11/43 (25.6%), p=0.86. At BCF, restaging Ga68-PSMA-PET-CT located distant metastases in 20 (63%) of the 32 patients (57% in cN1, and 73% in CI-M1a, p=0.47). Five-year biochemical failure-free survival (cN1; 77.4% and CI-M1a; 70.4%, p=0.43), distant metastasis-free survival (cN1; 86.9% and CI-M1a; 79.4%, p=0.23) and overall survival (cN1 92.6% and CI-M1a 90.1%, p=0.80) were similar in the two groups. Outcomes within CI-M1a were similar for proximal versus distal CI nodal location, 5-year BFFS 73.6% vs 58.6% (p=0.81).

CONCLUSION

Oligometastatic CI-M1a and cN1 prostate cancer patients showed similar outcomes when treated with curative whole pelvic radiotherapy and long-term ADT. The treatment for these 'oligometastatic' patients should be prospectively evaluated and optimized accordingly.

ACR-ABS-ASTRO Practice Parameter for Transperineal Permanent Brachytherapy of Prostate Cancer

AIM/OBJECTIVES/BACKGROUND

The American College of Radiology (ACR), American Brachytherapy Society (ABS), and American Society for Radiation Oncology (ASTRO) have jointly developed the following practice parameter for transperineal permanent brachytherapy of prostate cancer. Transperineal permanent brachytherapy of prostate cancer is the interstitial implantation of low-dose rate radioactive seeds into the prostate gland for the purpose of treating localized prostate cancer.

METHODS

This practice parameter was developed according to the process described under the heading The Process for Developing ACR Practice Parameters and Technical Standards on the ACR website (https://www.acr.org/Clinical-Resources/Practice-Parameters-and-Technical-Standards) by the Committee on Practice Parameters-Radiation Oncology of the Commission on Radiation Oncology, in collaboration with ABS and ASTRO.

RESULTS

This practice parameter provides a framework for the appropriate use of low-dose rate brachytherapy in the treatment of prostate cancer either as monotherapy or as part of a treatment regimen combined with external-beam radiation therapy. The practice parameter defines the qualifications and responsibilities of all involved radiation oncology personnel, including the radiation oncologist, medical physicist, dosimetrist, radiation therapist, and nursing staff. Patient selection criteria and the utilization of supplemental therapies such as external-beam radiation therapy and androgen deprivation therapy are discussed. The logistics of the implant procedure, postimplant dosimetry assessment, and best practices with regard to safety and quality control are presented.

CONCLUSIONS

Adherence to established standards can help to ensure that permanent prostate brachytherapy is delivered in a safe and efficacious manner.

Radiotherapy plus androgen-deprivation therapy for PSA persistence in lymph node-positive prostate cancer

The treatment for lymph node involvement (LNI) after radical prostatectomy (RP) has not been established. This study aimed to reveal the outcomes of various management strategies among patients with LNI after RP. Retrospectively, 561 patients with LNI after pelvic lymph node dissection (PLND) with RP treated between 2006 and 2019 at 33 institutions participating in the Japanese Urological Oncology Group were investigated. Metastasis-free survival (MFS) was the primary outcome. Patients were stratified by PSA persistence after RP. Cox regression models were used to analyze the relationships between clinicopathological characteristics and survival. Survival analyses were conducted using the Kaplan-Meier method and log-rank test with or without propensity score matching. Prognoses, including MFS and overall survival, were prominently inferior among patients with persistent PSA than among those without persistent PSA. In multivariate analysis, androgen-deprivation therapy (ADT) plus radiotherapy (RT) was associated with better MFS than ADT alone among patients with persistent PSA (hazard ratio = 0.37; 95% confidence interval = 0.15-0.93; P = 0.034). Similarly, MFS and overall survival were significantly better for ADT plus RT than for ADT alone among patients with persistent PSA after propensity score matching. This study indicated that PSA persistence in LNI prostate cancer increased the risk of poor prognoses, and intensive treatment featuring the addition of RT to ADT might improve survival.

Addition of Enzalutamide to Leuprolide and Definitive Radiotherapy is Tolerable and Effective in High-Risk Localized or Regional Non-Metastatic Prostate Cancer: Results from a Phase II Trial

Background

Enzalutamide is an antiandrogen used to treat both metastatic and nonmetastatic prostate cancer. Here we present results from a phase 2 trial designed to determine the safety, tolerability, and efficacy of adding enzalutamide to standard androgen deprivation therapy with radiation therapy in high-risk localized or regional, nonmetastatic patients with prostate cancer.

Methods and Materials

Enrollment criteria included at least 2 of the following: stage cT3a/b, prostate specific antigen (PSA) ≥20 ng/mL, Gleason grade 8 to 10, ≥33% core involvement on biopsy, or pelvic lymph node involvement on computed tomography or magnetic resonance imaging. Patients with metastatic disease were excluded. All patients received 24 months of leuprolide and enzalutamide, and 5 weeks of intensity modulated radiation therapy followed by a brachytherapy boost. Adverse events (AE), PSA, testosterone, and basic laboratory tests were then followed for up to 36 months. Primary outcomes were safety and tolerability and PSA complete response rate (PSA-CR, defined as PSA ≤0.3). Secondary outcomes included time to biochemical recurrence (BCR; nadir + 2 ng/mL).

Results

Sixteen patients were enrolled; 2 were ineligible and 3 withdrew before starting treatment. Median age at enrollment was 69.0 years (interquartile range [IQR] 11.5). Median treatment duration was 24.0 months (IQR 11.9). Median follow-up time was 35.5 months (IQR 11.2), and 9 of 11 (81.8%) patients completed the 36 months of follow-up. One of 11 (9%) patients had grade 4 AE (seizure), and no grade 5 AE were reported. Four of 11 (36.4%) patients had grade 3 AE, such as erectile dysfunction and hot flashes. All patients achieved PSA-CR, and median time to PSA-CR was 4.2 months (IQR 1.4). At 24 months follow-up, 0 of 11 (0%) patients had a biochemical recurrence. At 36 months, 1 of 9 (11.1%) patient had a biochemical recurrence. Of note, this patient did not complete the full 24 months of enzalutamide and leuprolide due to AEs.

Conclusions

Enzalutamide in combination with standard androgen deprivation therapy and radiation therapy was well-tolerated and effective warranting further study in a randomized controlled trial.

Safety and Efficacy Study of Neoadjuvant Radiohormonal Therapy for Oligometastatic Prostate Cancer: Protocol of an Open-Label, Dose-Escalation, Single-Centre Phase I/II Clinical Trial

BACKGROUND

The optimal treatment for oligometastatic prostate cancer (OMPC) is still on its way. Accumulating evidence has proven the safety and feasibility of radical prostatectomy and local or metastasis-directed radiotherapy for oligometastatic patients. The aim of this trial is to demonstrate the safety and feasibility outcomes of metastasis-directed neoadjuvant radiotherapy (naRT) and neoadjuvant androgen deprivation therapy (naADT) followed by robotic-assisted radical prostatectomy (RARP) for treating OMPC.

METHODS

The present study will be conducted as a prospective, open-label, dose-escalation, phase I/II clinical trial. The patients with oligometastatic PCa will receive 1 month of naADT, followed by metastasis-directed radiation and abdominal or pelvic radiotherapy. Then, radical prostatectomy will be performed at intervals of 4-8 weeks after radiotherapy, and ADT will be continued for 2 years. The primary endpoints of the study are safety profiles, assessed by the Common Terminology Criteria for Adverse Events (CTCAE) 5.0 grading scale, and perioperativemorbidities, assessed by the Clavien-Dindo classification system. The secondary endpoints include positive surgical margin (pSM), biochemical recurrence-free survival (bPFS), radiological progression-free survival (RPFS), postoperative continence, and quality of life (QoL) parameters.

DISCUSSION

The optimal treatment for OMPC is still on its way, prompting investigation for novel multimodality treatment protocol for this patient population. Traditionally, radical prostatectomy has been recommended as one of the standard therapies for localized prostate cancer, but indications have expanded over the years as recommended by NCCN and EAU guidelines. RP has been carried out in some centres for OMPC patients, but its value has been inconclusive, showing elevated complication risks and limited survival benefit. Neoadjuvant radiotherapy has been proven safe and effective in colorectal cancer, breast cancer and other various types of malignant tumors, showing potential advantages in terms of reducing metastatic stem-cell activity, providing clinical downstaging, and reducing potential intraoperative risks. Existing trials have shown that naRT is well tolerated for high-risk and locally-advanced prostate cancer. In this study, we hope to further determine the optimal irradiation dose and patient tolerance for genitourinary, gastrointestinal and systemic toxicities with the design of 3+3 dose escalation; also, final pathology can be obtained following RP to further determine treatment response and follow-up treatment plans.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, ChiCTR1900025743. http://www.chictr.org.cn/showprojen.aspx?proj=43065.

Dose-escalated pelvic radiotherapy for prostate cancer in definitive or postoperative setting

PURPOSE

Given the absence of standardized planning approach for clinically node-positive (cN1) prostate cancer (PCa), we collected data about the use of prophylactic pelvic irradiation and nodal boost. The aim of the present series is to retrospectively assess clinical outcomes after this approach to compare different multimodal treatment strategies in this scenario.

METHODS

Data from clinical records of patients affected by cN1 PCa and treated in six different Italian institutes with prophylactic pelvic irradiation and boost on pathologic pelvic lymph nodes detected with CT, MRI or choline PET/CT were retrospectively reviewed and collected. Clinical outcomes in terms of overall survival (OS) and biochemical relapse-free survival (b-RFS) were explored. The correlation between outcomes and baseline features (International Society of Urological Pathology-ISUP pattern, total dose to positive pelvic nodes ≤ / > 60 Gy, sequential or simultaneous integrated boost (SIB) administration and definitive vs postoperative treatment) was explored.

RESULTS

ISUP pattern < 2 was a significant predictor of improved b-RFS (HR = 0.3, 95% CI 0.1220-0.7647, P = 0.0113), while total dose < 60 Gy to positive pelvic nodes was associated with worse b-RFS (HR = 3.59, 95% CI 1.3245-9.741, P = 0.01). Conversely, treatment setting (postoperative vs definitive) and treatment delivery technique (SIB vs sequential boost) were not associated with significant differences in terms of b-RFS (HR = 0.85, 95% CI 0.338-2.169, P = 0.743, and HR = 2.39, 95% CI 0.93-6.111, P = 0.067, respectively).

CONCLUSION

Results from the current analysis are in keeping with data from literature showing that pelvic irradiation and boost on positive nodes are effective approaches. Upfront surgical approach was not associated with better clinical outcomes.

Treatment Strategies for High-Risk Localized and Locally Advanced and Oligometastatic Prostate Cancer

Simple Summary

The definitions of locally advanced and oligometastatic prostate cancer are ambiguous, and there are no standard treatments for these. Although multidisciplinary treatment combining systemic and local treatment may be effective, there are many unresolved issues such as the choice of local treatment, use of new endocrine agents and chemotherapy, and selection of optimal patients. The present article discusses the definitions, diagnoses, and treatment of very high-risk prostate cancer and oligometastatic prostate cancer.

Abstract

Despite the significant advances in the treatment of high-risk prostate cancer, patients with very high-risk features such as being locally advanced (clinical stage T3–4 or minimal nodal involvement), having a high Gleason pattern, or with oligometastasis may still have a poor prognosis despite aggressive treatment. Multidisciplinary treatment with both local and systemic therapies is thought to be effective, however, unfortunately, there is still no standard treatment. However, in recent years, local definitive therapy using a combination of radiotherapy and androgen deprivation is being supported by several randomized clinical trials. This study reviews the current literature with a focus on the definition of very high-risk prostate cancer, the role of modern imaging, and its treatment options.

Narrative review of management strategies and outcomes in node-positive prostate cancer

Pelvic nodal involvement is present in 13% of new prostate cancer diagnoses each year and is associated with a poor prognosis compared to localized disease. Grouped as stage IV along with distant metastatic disease, node-positive nonmetastatic patients historically received systemic therapy alone as primary treatment. This treatment paradigm has shifted as data have demonstrated that these patients may benefit from aggressive locoregional therapy and are potentially curable. There is currently a lack of randomized evidence to define the optimal management for node-positive patients. While a few trials have included node-positive patients, the majority of data are derived from large multi-institutional series or population-based series. This narrative review summarizes the current literature supporting curative-intent management strategies for patients diagnosed with nonmetastatic clinically node-positive prostate cancer (cN1M0), as well as patients found to have pathologic nodal disease at the time of surgery (pN1M0). Treatment of both scenarios requires multimodality considerations including surgery, radiation therapy (RT) and systemic therapy to minimize the risks of both locoregional and distant recurrence. Future considerations include developments in enhanced imaging and systemic therapy. Inclusion of node-positive patients on prospective, randomized trials such as NRG GU 008 is needed to enhance our understanding of optimal management strategies.

Intensity-Modulated Radiation Therapy with Simultaneous Integrated Boost for Clinically Node-Positive Prostate Cancer: A Single-Institutional Retrospective Study

Simple Summary

Recently, it has been shown that radiation therapy (RT) together with androgen-depletion therapy (ADT) might be more beneficial compared with ADT alone for clinically node-positive (cN1) prostate cancer. However, there are a limited number of studies that have addressed specific RT techniques and analyzed their clinical results. The present study was a retrospective analysis of cN1 prostate cancer patients treated with intensity-modulated radiation therapy with simultaneous integrated boost (SIB-IMRT), in addition to ADT, in our hospital. The present study suggests that ADT plus SIB-IMRT for cN1 prostate cancer treatment was safe and effective, was well tolerated, and had acceptable rates of late toxicity. Further prospective multicenter studies would be required to confirm the robustness of the present results.

Abstract

This study aimed to evaluate clinical outcomes and the toxicity of intensity-modulated radiation therapy with simultaneous integrated boost (SIB-IMRT) combined with androgen-deprivation therapy for clinically node-positive (cN1) prostate cancer. We retrospectively analyzed 97 patients with cN1 prostate cancer who received SIB-IMRT between June 2008 and October 2017 at our hospital. The prescribed dosages delivered to the prostate and seminal vesicle, elective node area, and residual lymph nodes were 69, 54, and 60 Gy in 30 fractions, respectively. Kaplan–Meier analysis was used to determine 5-year biochemical relapse-free survival (bRFS), relapse-free survival (RFS), overall survival (OS), and prostate cancer-specific survival (PCSS). Toxicity was evaluated using the Common Terminology Criteria for Adverse Events ver. 4.0. Over a median follow-up duration of 60 months, the 5-year bRFS, RFS, OS, and PCSS were 85.1%, 88.1%, 92.7% and 95.0%, respectively. Acute Grade 2 genito-urinary (GU) and gastro-intestinal (GI) toxicities were observed in 10.2% and 2.1%, respectively, with no grade ≥3 toxicities being detected. The cumulative incidence rates of 5-year Grade ≥2 late GU and GI toxicities were 4.7% and 7.4%, respectively, with no Grade 4 toxicities being detected. SIB-IMRT for cN1 prostate cancer demonstrated favorable 5-year outcomes with low incidences of toxicity.

Hong Kong Urological Association-Hong Kong Society of Uro-Oncology consensus statements on the management of advanced prostate cancer-2019 Updates

BACKGROUND

To update the Hong Kong Urological Association-Hong Kong Society of Uro-Oncology consensus statements on the management of advanced prostate cancer, the same panelists as in the previous consensus panel held a series of meetings to discuss updated clinical evidence and experiences.

METHODS

The previous consensus statements were retained, deleted, or revised, and new statements were added. At the final meeting, all statements were reviewed and amended as appropriate, followed by panel voting.

RESULTS

There were significant changes and additions to the previous consensus statements, primarily driven by the advances in androgen receptor signaling inhibitors, treatment sequencing in metastatic castration-resistant prostate cancer, and increasing recognition of oligometastatic prostate cancer since the introduction of prostate-specific membrane antigen positron emission tomography. In this update, a total of 59 consensus statements were accepted and established.

CONCLUSIONS

The consensus panel updated consensus statements on the management of advanced prostate cancer, aiming to allow physicians in the region to keep abreast of the recent evidence on optimal clinical practices.

Clinically Lymph Node Positive Prostate Cancer: At the Intersection of Focal and Systemic Disease Control

Clinically node-positive prostate cancer is often found at the time of diagnosis by cross-sectional imaging and remains poorly understood. Advanced imaging modalities such as magnetic resonance imaging nanoparticles or positron emission tomography-based molecular imaging stand to rapidly change the field and hopefully will bring better diagnostic clarity. This will allow for prospective clinical trials using radiographic, clinical, or molecular parameters to establish who may benefit from both localized and systemic treatment intensification and who may avoid overtreatment. Recent advances in metastatic hormone-sensitive disease may offer clues, but direct studies for nodal disease patients remain.

Pathologically Node-Positive Prostate Cancer: Casting for Cure When the Die Is Cast?

The postoperative management of men with lymph node involved prostate cancer (pN+) remains a challenge as there is a general lack of randomized trial data and a range of management strategies. Retrospective studies suggest a variable clinic course for patients with pN+ prostate cancer. Some men progress rapidly to metastatic disease despite further therapies, whereas other men can have a period of prolonged quiescence without adjuvant androgen deprivation therapy (ADT) or radiation therapy (RT). For men who have undergone radical prostatectomy, randomized trial data indicate that the addition of ADT in pN+ disease extends metastasis-free, prostate cancer-specific, and overall survival. Additional retrospective studies suggest that adding RT is potentially beneficial in this setting, improving overall and cancer-specific survival especially in men with certain pathologic parameters. Conversely, men with lower disease burden in their lymph nodes have longer times to progression and may be candidates for observation and salvage therapy as opposed to adjuvant ADT/RT.

Analysis of Radiation Facility Volume and Survival in Men With Lymph Node-Positive Prostate Cancer Treated With Radiation and Androgen Deprivation Therapy

IMPORTANCE

Long-term control of node-positive (N1) prostate cancer, the incidence of which is increasing, is obtainable with aggressive treatment, and definitive external beam radiation therapy (EBRT) with long-term androgen deprivation therapy (ADT) is an increasingly preferred option. Caring for these patients is complex and may require resources more readily available at high-volume centers.

OBJECTIVE

To evaluate the association between radiation facility case volume and overall survival (OS) in men with N1 prostate cancer.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study included 1899 men diagnosed with T1N1M0 to T4N1M0 prostate cancer treated with curative-intent EBRT and ADT between January 2004 and December 2016 at US facilities reporting to the National Cancer Database. Data analysis was performed from March to June 2020.

EXPOSURES

Treatment at a center with high vs low average cumulative facility volume (ACFV), defined as the total number of prostate radiation cases at an individual patient's treatment facility from 2004 until the year of that patient's diagnosis.

MAIN OUTCOMES AND MEASURES

OS was assessed between high- vs low-ACFV centers using the Kaplan-Meier method with and without propensity score-based weighted adjustment and multivariable Cox proportional hazards. The nonlinear association between continuous ACFV and OS was examined through a Martingale residual plot, and the optimal ACFV cutoff point that maximized the separation between high vs low ACFV was identified via a bias adjusted log rank test.

RESULTS

A total of 1899 men met inclusion criteria. The median (interquartile range) age was 66 (60-72) years, 1491 (78.5%) were White individuals, and 1145 (60.3%) were treated at nonacademic centers. The optimal ACFV cutoff point was 66.4 patients treated per year. The median OS for patients treated at high-ACFV vs low-ACFV centers was 111.1 (95% CI, 101.5-127.9) months and 92.3 (95% CI, 87.7-103.9) months, respectively (P = .01). On multivariable analysis, treatment at a low-ACFV center was associated with increased risk of death (HR, 1.22; 95% CI, 1.02-1.46, P = .03) compared with treatment at a high-ACFV center. These results persisted after propensity score-based adjustment.

CONCLUSIONS AND RELEVANCE

This cohort study found a significant association of facility case volume with long-term outcomes in men with N1 prostate cancer undergoing EBRT with ADT. Specifically, treatment at a facility with high radiation case volume was independently associated with longer OS. Further studies should focus on identifying which factors unique to high-volume centers may be responsible for this benefit.

The prognosis and the impact of radiotherapy in clinically regional lymph node-positive prostate cancer: Which patients are candidates for local therapy with radiation?

BACKGROUND

This study aimed to identify the prognostic and predictive factors of local radiotherapy in clinically regional lymph node-positive prostate cancer.

PATIENTS AND METHODS

This study includes patients who were newly diagnosed with regional lymph node-positive prostate cancer between 2008 and 2017. We investigated the prognostic value of clinicopathological parameters for progression-free survival (PFS) and overall survival (OS) as well as the differential prognostic impact of radiotherapy by subgroup analysis.

RESULTS

Among the 93 men enrolled as patients, 48 (51.6 %) were treated with radiotherapy. The biopsy positive core rate and biopsy Gleason score were associated with PFS, and the number of lymph node metastases was associated with both PFS and OS. Patients who underwent radiotherapy showed better PFS and OS. High-risk features (at least 2 criteria among ≥75% biopsy positive core rate, Gleason score ≥9, and ≥2 positive lymph nodes) were especially associated with improved outcomes after undergoing radiotherapy.

CONCLUSION

We identified prognostic factors for clinically regional lymph node-positive prostate cancer and showed the benefits of local radiation therapy. Patients with high-risk features may be especially suitable candidates for radiotherapy.

Cytokines, JAK-STAT Signaling and Radiation-Induced DNA Repair in Solid Tumors: Novel Opportunities for Radiation Therapy

A number of solid tumors are treated with radiation therapy (RT) as a curative modality. At the same time, for certain types of cancers the applicable doses of RT are not high enough to result in a successful eradication of cancer cells. This is often caused by limited pharmacological tools and strategies to selectively sensitize tumors to RT while simultaneously sparing normal tissues from RT. We present an outline of a novel strategy for RT sensitization of solid tumors utilizing Jak inhibitors. Here, recently published pre-clinical data are reviewed which demonstrate the promising role of Jak inhibition in sensitization of tumors to RT. A wide number of currently approved Jak inhibitors for non-malignant conditions are summarized including Jak inhibitors currently in clinical development. Finally, intersection between Jak/Stat and the levels of serum cytokines are presented and discussed as they relate to susceptibility to RT.

Three-tiered Subclassification System of High-risk Prostate Cancer in Men Managed With Radical Prostatectomy: Implications for Treatment Decision-making

OBJECTIVE

To inform treatment decisions for patients with high-risk prostate cancer (PCa), we determined rates of adverse pathologic factors and overall survival (OS) among subgroups of high-risk men.

METHODS

Using the National Cancer Database, 89,450 patients with clinical N0M0 unfavorable intermediate-risk, favorable high-risk (cT1c, Gleason 6, prostate-specific antigen [PSA] > 20 ng/mL or cT1c, biopsy Gleason 8, PSA < 10 ng/mL), standard high-risk (all other cT3a, biopsy Gleason ≥ 8, or PSA > 20 ng/mL), or very high-risk (cT3b-T4 or biopsy primary Gleason pattern 5) PCa treated with radical prostatectomy were identified. Rates of adverse pathologic factors (positive surgical margins, T4 disease, or pathologic lymph node involvement) were compared across subgroups.

RESULTS

Patients with unfavorable intermediate-risk (n = 31,381) and favorable high-risk (n = 10,296) disease had similar rates of adverse features (7.6% vs 8.2%, adjusted odds ratio 1.00, 95% confidence interval 0.92-1.08, P= .974). Patients with standard high-risk (n = 30,260) or very high-risk (n = 7513) disease were significantly more likely to have adverse pathologic factors (15.9% and 26.5%, P < .001 for both). Patients with unfavorable intermediate-risk and favorable high-risk disease had similar 5-year OS (95.7% vs 95.1%, adjusted hazard ratio 1.06, 95% confidence interval 0.92-1.21, P = .411) but better OS compared to standard and very high-risk patients (93.4% and 88.1%, respectively; P < .001).

CONCLUSION

Unfavorable intermediate-risk or favorable high-risk PCa patients had low rates of adverse pathologic factors and similar OS. In contrast, standard and very high-risk PCa patients had significantly higher rates of adverse pathologic factors and worse OS. This 3-tiered subclassification of high-risk disease may allow for improved treatment selection among patients considering surgery.

Clinical outcomes of definitive whole pelvic radiotherapy for clinical lymph node metastatic prostate cancer

Background

In this study, we aim to present the clinical outcomes of radiotherapy (RT) in clinical pelvic lymph node‐positive prostate cancer (cN1) patients. We also analyze the prognostic factors with focus on RT dose escalation to metastatic lymph nodes (LN).

Methods

We retrospectively analyzed the data from cN1 patients who were treated with definitive RT and androgen deprivation therapy (ADT) between June 2004 and February 2016. All patients received localized irradiation to the prostate region and whole pelvis irradiation. Some patients received intensity‐modulated radiation therapy with RT dose escalation to metastatic LN. Univariate analyses using log‐rank test were performed to find prognostic factors between patient subgroups.

Results

Fifty‐one consecutive patients were identified. The median follow‐up period for all patients was 88 (range 20‐157) months. Primary Gleason pattern and LN RT dose were statistically significant prognostic factors for relapse‐free survival (RFS) and distant metastasis‐free survival (DMFS). Especially, RT dose escalation (60 Gy or more) to metastatic LN significantly improved RFS and DMFS compared with standard dose RT (4‐year RFS 90.6% vs 82.1%, 7‐year RFS 90.6% vs 58.0%, P = .015; 4‐year DMFS 90.6% vs 82.1%, 7‐year DMFS 90.6% vs 62.8%, P = .023). The following factors were all statistically significant for biochemical relapse‐free survival (BRFS): T stage, LN RT dose, local RT dose, and ADT duration period. Any significantly different toxicity was not seen for each LN or local RT dose except for the incident rate of grade 2 or more acute urinary retention, which was significantly higher in the higher LN RT dose (60 Gy or more) group by the Chi‐square test.

Conclusions

RT dose escalation to metastatic LN in cN1 patients improves BRFS, RFS, and DMFS at 4 and 7 years, without increasing severe adverse events.

Prognostic factors influencing overall survival in de novo oligometastatic prostate cancer patients

BACKGROUND

Oligometastatic cancer has been suggested as an intermediate state between localized disease and wide-ranging metastases. The clinical significance of local treatment in oligometastatic prostate cancer (PCa) has been a recent topic of interest. However, standard definitions of oligometastasis are lacking. Here we studied risk factors among Japanese de novo oligometastatic patients with PCa.

METHODS

We retrospectively assessed clinical data from 264 patients, including locally advanced (T3 or T4N0M0) cancer, lymph-node-positive cancer (T_any N1M0), and cancer with ≤10 bone metastases. All patients received androgen deprivation therapy only. The number of bone metastases and clinical factors were evaluated in association with overall survival (OS) and progression-free survival (PFS). The Mann-Whitney U test, Cox proportional hazard models, and Kaplan-Meier methods were used as statistical analyses.

RESULTS

Median age, PSA at baseline and OS were 74 years, 55.2 ng/mL, and 129.0 months, respectively. The cutoff for the number of bone metastases having the greatest impact on OS was ≥3 (hazard ratio [HR]: 2.67; P = .0001). In multivariate analysis, non-regional lymph node (LN) metastases (HR: 2.15; P = .0222), ISUP grade group (GG) 5 (HR: 2.04; P = .0186) and ≥3 bone metastases (HR: 1.82; P = .0390) were independent predictors of OS. In risk classification based on these factors, OS and PFS were significantly classifiable into poor (2-3 factors), intermediate (1 factor), and good (no factors) risk groups (P < .0001).

CONCLUSION

Not only the number of bone metastases, but also non-regional LN metastases predict OS in patients with de novo oligometastatic PCa.

The Horse is at the Stable Door: Management of N1M0 Prostate Cancer

Pelvic lymph node involvement in prostate cancer is a significant poor prognostic factor with very little evidence on the optimal management options for these patients. It is estimated that lymph node-positive patients make up 12% of newly diagnosed prostate cancer and this figure is expected to rise with the advancement and increasing use of novel imaging. The controversy around this subgroup of patients is whether this is an intermediary stage before disseminated disease and hence amenable to curative treatment options. Systemic therapies have been the mainstay of treatment for these patients for decades, but in recent years, studies have emerged supporting the addition of local therapy. This review will focus on the current multimodal management approach for clinical and pathological lymph node-positive prostate cancer with a focus on radiotherapy options and aims to provide the rationale for a curative approach with a combination of local and systemic therapy.

[When to introduce hormone therapy after total prostatectomy with positive lymph nodes? Study of the factors influencing the time of introduction of hormone therapy]

INTRODUCTION

Adjuvant hormone therapy is the standard treatment after total prostatectomy with positive lymph node. However, this treatment has side effects and at the time of the PSA era and extensive lymph node dissection, this principle is questioned. The aim of this study is to describe the oncological characteristics of patients that may explain the delay in introducing hormone therapy in patients with positive lymph node.

METHODS

Monocentric, retrospective study of 161 patients from November 1988 to February 2018 in a single French University Hospital, having undergone radical prostatectomy with positive lymph nodes on pathology. For each patient, preoperative data (age, clinical stage, biopsy results, d'Amico classification) and postoperative data (pathological results, number of lymph nodes removed, number of positive lympnodes, recurrence free survival, specific survival and overall survival) were collected. The date of introduction of hormone therapy was noted and survival without hormonal therapy was established according to the Kaplan Meier curve. The pre- and post-operative oncological factors that could influence hormone therapy introduction were investigated with Chi² and Student tests (statistically significant when P<0.05).

RESULTS

The mean number of lymph nodes removed was 12 [1-40]. The mean number of positive lymph nodes was 2.5 [1-24], the mean percentage of positive lymph nodes was 25% (2.5-100). After a mean follow-up of 95 months (3-354), 88 patients (54.6%) had no hormonal treatment. The average time to hormonal treatment was 40 months [0-310]. At 3 years, survival without hormone therapy was 52% and 51% at 5 years. Only the percentage of positive lymphnodes appeared to be a significant predictor of the introduction of hormone therapy. (29.32% vs. 21.99%, P=0.047). Hormone-free survival was significantly higher in patients with lymph node involvement less than 25% (P<0.0001) or with less than 2 positive lymph nodes (P=0.0294).

CONCLUSION

Lymph node invasion is a factor of poor prognosis after total prostatectomy and leads to introduce hormone therapy. Our study identified the percentage and number of positive lymph nodes as factors that identify patients who may be delayed in introducing this hormone therapy.

LEVEL OF PROOF

3.

PSMA-PET guided dose-escalated volumetric arc therapy (VMAT) for newly diagnosed lymph node positive prostate cancer: Efficacy and toxicity outcomes at two years

PURPOSE/OBJECTIVES

There are no published reports of prostate specific membrane antigen (PSMA) positron emission tomography (PET) guided dose-escalated intensity-modulated radiation therapy (DE-IMRT) in newly diagnosed lymph node (LN) positive prostate cancer. We report early toxicity and efficacy outcomes with this approach.

MATERIALS/METHODS

Patients with newly diagnosed high-risk prostate cancer were staged using PSMA PET, computed tomography (CT) and bone scans. Patients with LN positive-only metastases were offered curative therapy using 3 months androgen deprivation therapy (ADT) followed by DE-IMRT (using volumetric arc therapy), and 3 years adjuvant ADT. All patients had fiducial marker insertion, with privately insured patients having spacer hydrogel insertion. PET and prostate magnetic resonance imaging were fused with the planning CT. We aimed to deliver 81 Gy in 45 fractions (Fx) to the prostate and PET-positive LNs, and 60 Gy in 45Fx to bilateral elective pelvic LNs.

RESULTS

In all, 46 patients were treated, with 83% Gleason 8-10, 67% T3/T4, median number of LNs 2 (range 1-6), and median PET-positive LN volume 1.14 cc (range 0.15-4.14). LNs were outside of standard contouring guidelines in 37% of patients. The mean PET-positive LN clinical target volume dose ranged from 73.3 to 85.9 Gy (median 83.6 Gy). With 24 months median follow-up, two year failure-free survival was 100%, and 2 year overall survival 95.7%. Acute grade 1 and 2 GI toxicity occurred in 48 and 11% of patients, and GU toxicity in 72 and 24%. Late grade 1, 2 and 3 GI toxicity occurred in 13, 2 and 0%, and GU toxicity 28, 13 and 4%. No toxicity was attributable to the high dose LN boost.

CONCLUSIONS

PSMA PET-guided DE-IMRT up to 81 Gy to the prostate and involved LNs, and long term ADT, is a promising approach for newly diagnosed LN positive prostate cancer. LN contouring guidelines require re-evaluation in the era of PSMA PET imaging.

Practice Patterns and Outcomes Among Patients With N0M0 Prostate Cancer and a Very High Prostate-Specific Antigen Level

Background: Management of patients with a very high prostate-specific antigen (PSA) level (≥98.0 ng/mL) but clinically localized (N0M0) prostate cancer is challenging. This study sought to determine practice patterns and outcomes among these patients. Patients and Methods: A total of 748,825 patients with prostate cancer from 2004 through 2012 were identified using the National Cancer Database. These patients were subdivided by PSA level (0–9.9, 10.0–19.9, 20.0–39.9, 40.0–59.9, 60.0–79.9, 80.0–97.9, and ≥98.0 ng/mL), nodal status (N0 vs N1), and distant metastases (M0 vs M1). Rates of locoregional treatment and 5-year overall survival (OS) in each group were determined. Survival was compared using Cox regression after adjusting for multiple patient-specific factors. Results: The rate of locoregional treatment for patients with N0M0 disease and PSA level ≥98.0 ng/mL was significantly lower than for those with N1M0 disease (52.6% vs 60.4%; P<.001) or N0M0 disease and PSA level <98.0 ng/mL (52.6% vs 86.6%; P<.001). The 5-year OS rate was similar for patients with N1M0 disease and those with N0M0 disease and a very high PSA level (63.2% vs 59.1%; adjusted hazard ratio [aHR], 0.91; P=.063). The survival benefit associated with locoregional treatment was higher among those with N0M0 disease and a very high PSA level than among those with N1M0 disease (aHR, 0.28 vs 0.44; P<.001). Conclusions: Patients with clinical N0M0 disease and a very high PSA level (≥98.0 ng/mL) have outcomes similar to those with N1 disease but receive locoregional treatment at a lower rate. Future work is needed to investigate the utility of locoregional treatment in this population.

Intensity-modulated radiotherapy for prostate cancer with seminal vesicle involvement (T3b): A multicentric retrospective analysis

OBJECTIVES

No study has reported clinical results of external-beam radiotherapy specifically for T3b prostate cancer. The possibility of escalating the dose to the involved seminal vesicles (ISV) while respecting the dose constraints in the organs at risk is thus so far not clearly demonstrated. The objective of the study was to analyze the dose distribution and the clinical outcome in a large series of patients who received IMRT for T3b prostate cancer.

MATERIALS AND METHODS

This retrospective analysis included all patients who received IMRT and androgen deprivation therapy for T3b prostate cancer, between 2008 and 2017, in six French institutions, with available MRI images and dosimetric data.

RESULTS

A total of 276 T3b patients were included. The median follow-up was 26 months. The median (range) prescribed doses (Gy) to the prostate and to the ISV were 77 (70-80) and 76 (46-80), respectively. The dose constraint recommendations were exceeded in less than 12% of patients for the rectum and the bladder. The 5-year risks of biochemical and clinical recurrences and cancer-specific death were 24.8%, 21.7%, and 10.3%, respectively. The 5-year risks of local, pelvic lymph node, and metastatic recurrences were 6.4%, 11.3%, and 15%, respectively. The number of involved lymph nodes (≤ 2 or ≥ 3) on MRI was the only significant prognostic factor in clinical recurrence (HR 9.86) and death (HR 2.78). Grade ≥ 2 acute and 5-year late toxicity rates were 13.2% and 12% for digestive toxicity, and 34% and 31.5% for urinary toxicity, respectively. The dose to the pelvic lymph node and the age were predictive of late digestive toxicity.

CONCLUSION

IMRT for T3b prostate cancer allows delivery of a curative dose in the ISV, with a moderate digestive toxicity but a higher urinary toxicity. Lymph node involvement increases the risk of recurrence and death.

Which Patients with Clinically Node-positive Prostate Cancer Should Be Considered for Radical Prostatectomy as Part of Multimodal Treatment? The Impact of Nodal Burden on Long-term Outcomes

BACKGROUND

A role for local therapies including radical prostatectomy (RP) in prostate cancer (PCa) patients with clinical lymphadenopathies has been proposed. However, no data are available to identify men who would benefit from RP in this setting.

OBJECTIVE

To identify predictors of clinical recurrence (CR) in surgically managed PCa patients with clinical lymphadenopathies.

DESIGN, SETTING, AND PARTICIPANTS

We identified 162 patients with lymphadenopathies treated with RP and lymph node dissection at three referral centers.

OUTCOME MEASURES AND STATISTICAL ANALYSES

CR was defined as the onset of metastases detected by conventional imaging. Kaplan-Maier analyses assessed time to CR after stratifying patients according to the site of lymphadenopathies and nodal burden. Regression tree analysis stratified patients into risk groups on the basis of their preoperative characteristics.

RESULTS AND LIMITATIONS

Overall, 80% of patients had lymphadenopathies in the pelvis alone and 20% in the retroperitoneum±pelvis. The median size of positive nodes was 13mm. A total of 84 patients (52%) received neoadjuvant androgen deprivation therapy and 127 (78%) had pathological lymph node invasion. The median follow-up for survivors was 64 mo. The 8-yr CR-free and CSM-free survival rates were 59% and 80%, respectively. Biopsy grade group and preoperative nodal burden should identify patients more likely to experience CR. While <10% of men with biopsy grade group 1-3 and two or fewer clinical lymphadenopathies developed CR, up to 60% of patients with biopsy grade group 4-5 and retroperitoneal node involvement ultimately experienced CR at 8 yr after RP. The discrimination of the regression tree was 76% according to the area under the receiver operating characteristic curve. Our study is limited by potential unmeasured confounders and the relatively small sample size.

CONCLUSIONS

Surgery in a multimodal setting might play a role in PCa patients with biopsy grade group 1-3 and/or enlarged nodes in the pelvis. Conversely, grade group 4-5 PCa and lymphadenopathies in the retroperitoneum are associated with worse oncologic outcomes.

PATIENT SUMMARY

Approximately half of prostate cancer patients with clinical lymphadenopathies treated with radical prostatectomy are free from metastases at 8-yr follow-up. Radical prostatectomy with or without systemic therapies might play a role in selected patients with biopsy grade group 1-3 disease and/or enlarged nodes in the pelvis. Conversely, a higher grade group and the presence of lymphadenopathies in the retroperitoneum should identify candidates for systemic therapies upfront.

Novel Insights into the Management of Oligometastatic Prostate Cancer: A Comprehensive Review

CONTEXT

The current standard of care for metastatic prostate cancer (PCa) is androgen deprivation therapy (ADT) plus either docetaxel or abiraterone. Growing evidence suggests that metastasis-directed therapy (MDT) and/or local therapy targeted to the primary tumour (ie, prostate) may be of benefit in the setting of oligometastatic disease. Several prospective studies are underway; however, until robust evidence is available to guide treatment decisions, physicians are challenged with how best to manage patients with oligometastases.

OBJECTIVE

This comprehensive review aims to collate the available evidence to date for a role of MDT and/or prostate-targeted therapy in the setting of oligometastatic PCa, as well as discuss ongoing trials in this setting.

EVIDENCE ACQUISITION

We searched PubMed for the combination of "prostate cancer" and "oligometastatic", "oligometastases", "oligometastasis", "solitary metastases", "stereotactic body radiotherapy", "SBRT", "stereotactic ablative radiotherapy", "SABR", "salvage lymphadenectomy", or "metastasectomy" in publications over the last 20yr. We also searched ClinicalTrials.gov to identify relevant ongoing trials.

EVIDENCE SYNTHESIS

The studies were divided according to the timing of metastasis into synchronous (ie, detected at the time of primary PCa diagnosis) and metachronous (ie, detected after treatment of the primary tumour), and according to treatment modality into MDT (including salvage lymph node dissection [sLND]) and prostate-targeted treatment. For MDT of synchronous/metachronous metastases, we included 16 completed studies and 11 ongoing prospective studies. In the case of sLND for nodal-only recurrence after primary treatment with curative intent, we included 11 completed studies. Finally, for prostate-targeted treatment of synchronous metastatic PCa, we included 25 completed studies and 11 ongoing prospective studies. In selected patients with oligorecurrent disease, early detection and aggressive treatment of metastatic lesions (surgery or radiotherapy) appears to be a feasible strategy and may delay the use of systemic therapies. MDT is a promising option in oligometastatic PCa patients, but more robust data are needed. In the setting of synchronous oligometastatic disease, aggressive cytoreductive treatment needs further data to confirm the benefits.

CONCLUSIONS

In this review, we provide a comprehensive overview of the current literature on the treatment of patients with oligometastatic PCa. The data suggest that although ADT plus either docetaxel or abiraterone remains the mainstay of treatment for mPCa, in oligometastatic PCa, improved outcomes may be achieved with metastasis- and prostate-targeted therapies. The studies included in this review are mainly retrospective in nature, limiting the strength of the evidence they provide. Prospective studies are ongoing, and their results are eagerly awaited.

PATIENT SUMMARY

We reviewed the treatment of patients with prostate cancer that has spread to five sites or fewer. We conclude that while androgen deprivation plus either docetaxel or abiraterone should remain the standard of care, there is evidence that treatment targeted at the metastases and the primary tumour may improve the outcome for the patient and potentially delay the use of systemic treatment.

Radiotherapy for recurrent prostate cancer: 2018 Recommendations of the Australian and New Zealand Radiation Oncology Genito-Urinary group

The management of patients with biochemical, local, nodal, or oligometastatic relapsed prostate cancer has become more challenging and controversial. Novel imaging modalities designed to detect recurrence are increasingly used, particularly PSMA-PET scans in Australia, New Zealand and some European countries. Imaging techniques such as MRI and PET scans using other prostate cancer-specific tracers are also being utilised across the world. The optimal timing for commencing salvage treatment, and the role of local and/or systemic therapies remains controversial. Through surveys of the membership, the Australian and New Zealand Faculty of Radiation Oncology Genito-Urinary Group (FROGG) identified wide variation in the management of recurrent prostate cancer. Following a workshop conducted in April 2017, the FROGG management committee reviewed the literature and developed a set of recommendations based on available evidence and expert opinion, for the appropriate investigation and management of recurrent prostate cancer. These recommendations cover the role and timing of post-prostatectomy radiotherapy, the management of regional nodal metastases and oligometastases, as well as the management of local prostate recurrence after definitive radiotherapy.

Comparative Effectiveness of Local and Systemic Therapy for T4 Prostate Cancer

OBJECTIVE

To evaluate the comparative effectiveness of local vs systemic therapy among patients diagnosed with nonmetastatic clinical T4 prostate cancer.

METHODS

Using the National Cancer Database men with clinical T4N0-1M0 prostate cancer from 2004 to 2013 were identified. Local therapy was defined as radiation (RT with androgen deprivation therapy [ADT]), surgery (radical prostatectomy with ADT), or combined radiation plus surgery (radical prostatectomy plus RT with ADT). Systemic therapy was defined as ADT or chemotherapy alone. The primary outcome of overall survival was estimated using the Kaplan-Meier method. Factors associated with overall survival were determined by Cox proportional hazards models.

RESULTS

A total of 1914 patients were included in our analysis, 1559 received local therapy and 355 received systemic therapy. Median 5-year survival for local vs systemic therapy was 41.5 and 28.2 months, respectively. On multivariable analysis, local therapy was associated with increased overall survival compared to systemic therapy (hazard ratio [HR] = 0.52; 95% confidence interval [CI] 0.44-0.62, P < .001). Comparing local therapy treatment modalities, both radiation (HR = 0.44; 95% CI 0.36-0.53, P < .001) and surgery (HR = 0.67; 95% CI 0.55-0.82, P < .001) were associated with increased overall survival compared to systemic therapy. Among those receiving local therapy, more patients were treated with radiation (n = 709/1559 or 45.5%) compared to surgery (n = 560/1559 or 35.9%) or combined radiation plus surgery (n = 290/1559 or 18.6%) with 5-year overall survival by treatment type being 61%, 51.4%, and 62.2%, respectively.

CONCLUSION

Local therapy for clinical T4 prostate cancer is associated with improved overall survival. Due to the retrospective, nonrandomized nature of the study design, a clinical trial is needed to better define the efficacy of local therapy in this high-risk patient population.

Treatment of Oligometastatic Hormone-Sensitive Prostate Cancer: A Comprehensive Review

With advancements in diagnostic techniques, including molecular and clinical imaging, that directly target cancer cells, oligometastatic prostate cancer (PCa) is being diagnosed in patients who were, in the past, considered to have localized disease. With accumulating evidence, there has been a paradigm shift in considering aggressive treatments targeted at both the primary tumor and metastatic lesions in an aim to avoid and delay the need for palliative treatments and, ultimately, to achieve survival benefits. However, many questions still remain unanswered regarding the understanding of oligometastatic PCa, from its definition to optimal treatment strategies for each individual. Limited retrospective studies have suggested that interventions, including local and/or metastasis-directed therapy using surgery and radiation therapy (RT), can improve survival outcomes with minimal risk of adverse effects. Such treatments have been shown to decrease the risks of subsequent palliative interventions and to delay the start of androgen-deprivation therapy. Nevertheless, available data are insufficient to draw a reliable conclusion regarding their effect on quality of life measures and overall survival. This comprehensive review overviews data from contemporary literature that have investigated treatments, including surgery and RT, for patients with oligometastatic PCa, namely pelvic lymph node positive disease and limited distant metastases, and summarizes ongoing trials that are evaluating the feasibility of aggressive multimodal treatments.