Salvage lymph node dissection after 68Ga-PSMA or 18F-FEC PET/CT for nodal recurrence in prostate cancer patients

Safety and efficiency of repeat salvage lymph node dissection for recurrence of prostate cancer using PSMA-radioguided surgery (RGS) after prior salvage lymph node dissection with or without initial RGS support

BACKGROUND AND OBJECTIVE

Metastasis-directed therapy is a feasible option for low PSA, recurrent locoregional metastatic prostate cancer. After initial salvage surgery, patients with good response might consider a repeat salvage surgery in case of recurrent, isolated, and PSMA-positive metastases. This analysis aimed to evaluate the oncological outcome and safety of repeat PSMA-targeted radioguided surgery (RGS) after either prior RGS or "standard" salvage lymph node dissection (SLND).

MATERIALS AND METHODS

We identified 37 patients undergoing repeat RGS after prior SLND (n = 21) (SLND-RGS) or prior RGS (n = 16) (RGS-RGS) between 2014 and 2021 after initial radical prostatectomy with or without pelvic radiation therapy at two German tertiary referral centers. Kaplan-Meier analyses and uni-/multivariable Cox regression models were used to investigate factors associated with biochemical recurrence-free survival (BRFS) and treatment-free survival (TFS) after repeat salvage surgery.

RESULTS AND LIMITATIONS

Complete Biochemical Response (cBR, PSA < 0.2 ng/ml) was observed in 20/32 patients (5 NA). Median overall BRFS [95% confidence interval (CI)] after repeat salvage surgery was 10.8 months (mo) (5.3-22). On multivariable regression, only age (HR 1.09, 95% CI 1.01-1.17) and preoperative PSA (HR 1.23, 95% CI 1.01-1.50) were associated with shorter BRFS, although PSA (HR 1.16, 95% CI 0.99-1.36) did not achieve significant predictor status in univariable analysis before (p value = 0.07). Overall, one year after second salvage surgery, 89% of the patients (number at risk: 19) did not receive additional treatment and median TFS was not reached. Clavien-Dindo grade > 3a complications were observed in 8% (3/37 patients). Limitations are the retrospective evaluation, heterogeneous SLND procedures, lack of long-term follow-up data, and small cohort size.

CONCLUSION

In this study, repeat RGS was safe and provided clinically meaningful biochemical recurrence- and treatment-free intervals for selected cases. Patients having low preoperative PSA seemed to benefit most of repeat RGS, irrespective of prior SLND or RGS or the time from initial RP/first salvage surgery.

Outcome of patients with biochemical recurrence of prostate cancer after PSMA PET/CT-directed radiotherapy or surgery without systemic therapy

BACKGROUND

Radiotherapy (RT) and surgery are potential treatment options in patients with biochemical recurrence (BCR) following primary prostate cancer treatment. This study examines the value of prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT)-informed surgery and RT in patients with BCR treated without systemic therapy.

METHODS

This is a post-hoc subgroup analysis of a prospective clinical trial. Inclusion criteria were: histologically proven prostate cancer at initial curative-intent treatment, BCR after primary treatment with curative intent, having five or fewer lesions identified on [¹⁸F]DCFPyL PET/CT, and treatment with either PET/CT-directed RT or surgery without systemic therapy. The biochemical progression-free survival after PSMA ligand PET/CT-directed RT and surgery was determined. Uni- and multivariate Cox regression analyses were performed for the association of patients' characteristics, tumor-specific variables, and PSMA PET/CT imaging results with biochemical progression at the last follow-up.

RESULTS

Fifty-eight patients (30 in surgery and 28 in radiotherapy groups) met the inclusion criteria. A total of 87 PSMA-positive lesions were detected: 16 local recurrences (18.4%), 54 regional lymph nodes (62.1%), 6 distant lymph nodes (6,8%), and 11 osseous lesions (12.7%). A total of 85.7% (24 of 28) and 70.0% (21 of 30) of patients showed a ≥ 50% decrease in prostate-specific antigen (PSA) levels after RT and surgery, respectively. At a median follow-up time of 21 months (range, 6-32 months), the median biochemical progression-free survival was 19 months (range, 4 to 23 months) in the radiotherapy group, as compared with 16.5 months (range, 4 to 28 months) in the surgery group. On multivariate Cox regression analysis, the number of PSMA positive lesions (2-5 lesions compared to one lesion), and the anatomic location of the detected lesions (distant metastasis vs. local relapse and pelvic nodal relapse) significantly correlated with biochemical progression at the last follow-up, whereas other clinical, tumor-specific, and imaging parameters did not.

CONCLUSIONS

This study suggests that RT or surgery based on [¹⁸F]DCFPyL PET/CT are associated with high PSA response rates. The number and site of lesions detected on the PSMA PET/CT were predictive of biochemical progression on follow-up. Further studies are needed to assess the impact of targeting these sites on patient relevant outcomes.

TRIAL REGISTRATION

Registered September 14, 2016; NCT02899312; https://clinicaltrials.gov/ct2/show/NCT02899312.

Role of Local and/or Metastasis-directed Therapy in Patients with Hormone-sensitive M1a Prostate Cancer-A Systematic Review

CONTEXT

It remains unclear whether men with hormone-sensitive prostate cancer (PCa) metastasized to nonregional lymph nodes (M1a) benefit from prostate-directed therapy (PDT) and/or metastasis-directed therapy (MDT).

OBJECTIVE

To systematically summarize the literature regarding oncological outcomes of de novo and recurrent M1a PCa patients treated with PDT and/or MDT.

EVIDENCE ACQUISITION

We searched Medline (Ovid), Embase, and Scopus according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines for reports on oncological outcomes of de novo or recurrent hormone-sensitive M1a PCa patients treated with PDT (radical prostatectomy or radiotherapy) and/or MDT (nodal radiotherapy or salvage lymph node dissection) with or without androgen deprivation therapy. A descriptive data synthesis and a methodological quality assessment were performed to evaluate the impact of PDT and/or MDT on survival in M1a PCa patients.

EVIDENCE SYNTHESIS

A total of 6136 articles were screened and 24 studies were included in this systematic review. In de novo M1a PCa patients, PDT was associated with improved oncological outcomes compared with no PDT. In recurrent M1a PCa, MDT could delay the need for systemic treatment in a selection of patients, but high-level evidence from prospective phase III randomized controlled trials is still awaited.

CONCLUSIONS

This systematic review summarized the limited literature data on the management of M1a PCa. Subgroup analyses suggest a role for PDT plus systemic therapy in de novo M1a PCa. MDT to distant nodal metastases delayed the need for systemic therapy in recurrent disease, but robust data are lacking. The predominantly retrospective nature of the included studies and significant heterogeneity in study designs limit the strength of evidence.

PATIENT SUMMARY

We reviewed the treatment of patients with prostate cancer that has spread to lymph nodes outside the pelvis without metastases in other organ systems. There is evidence that treatment of the primary prostate tumor improves outcomes in well-selected patients and that treatment targeting distant lymph node metastases can delay the start of systemic treatment.

Necessity of Pelvic Lymph Node Irradiation in Patients with Recurrent Prostate Cancer after Radical Prostatectomy in the PSMA PET/CT Era: A Narrative Review

The main prostate cancer (PCa) treatments include surgery or radiotherapy (with or without ADT). However, none of the suggested treatments eliminates the risk of lymph node metastases. Conventional imaging methods, including MRI and CT scanning, are not sensitive enough for the diagnosis of lymph node metastases; however, the novel imaging method, PSMA PET/CT scanning, has provided valuable information about the pelvic LN involvement in patients with recurrent PCa (RPCa) after radical prostatectomy. The high sensitivity and negative predictive value enable accurate N staging in PCa patients. In this narrative review, we summarize the evidence on the treatment and extent of radiation in prostate-only or whole-pelvis radiation in patients with positive and negative LN involvement on PSMA PET/CT scans.

Simultaneous treatment of a pubovesical fistula and lymph node metastasis secondary to multimodal treatment for prostate cancer: Case report and review of the literature

Pubovesical fistula (PVF) is a rare complication of radical treatments for prostate cancer (PCa), especially when a multimodal approach is performed. We present a case of PVF with extensive communication between the bladder and the pubic bones, and lymph node metastases of PCa treated by cystectomy and salvage lymphadenectomy. We describe a case of a 65-year old male patient who, after radical prostatectomy and adjuvant radiation therapy, suffered from suprapubic and perineal pain, ambulation difficulties and recurrent urinary tract infections. Cystoscopy, cystography and contrast-enhanced magnetic resonance imaging diagnosed a PVF. Choline positron emission tomography/computed tomography scan demonstrated PCa lymph node metastases. After the failure of conservative treatment, open radical cystectomy with ureterocutaneostomy diversion and salvage lymphadenectomy were performed with resolution of symptoms. At 3-month follow-up, the pelvic and perineal pain was completely regressed and 1-year later the patient was still asymptomatic. This clinical case shows efficacy and safety of combined salvage lymphadenectomy and cystectomy with urinary diversion for the treatment of late PCa node metastasis and PVF.

The current role of precision surgery in oligometastatic prostate cancer

Oligometastatic prostate cancer (omPCa) is a novel intermediate disease state characterized by a limited volume of metastatic cells and specific locations. Accurate staging is paramount to unmask oligometastatic disease, as provided by prostate-specific membrane antigen-positron emission tomography. Driven by the results of prospective trials employing conventional and/or modern staging modalities, the treatment landscape of omPCa has rapidly evolved over the last years. Several treatment-related questions comprising the concept of precision strikes are under development. For example, beyond systemic therapy, cohort studies have found that cytoreductive radical prostatectomy (CRP) can confer a survival benefit in select patients with omPCa. More importantly, CRP has been consistently shown to improve long-term local symptoms when the tumor progresses across disease states due to resistance to systemic therapies. Metastasis-directed treatments have also emerged as a promising treatment option due to the visibility of oligometastatic disease and new technologies as well as treatment strategies to target the novel PCa colonies. Whether metastases are present at primary cancer diagnosis or detected upon biochemical recurrence after treatment with curative intent, targeted yet decisive elimination of disseminated tumor cell hotspots is thought to improve survival outcomes. One such strategy is salvage lymph node dissection in oligorecurrent PCa which can alter the natural history of progressive PCa. In this review, we will highlight how refinements in modern staging modalities change the classification and treatment of (oligo-)metastatic PCa. Further, we will also discuss the current role and future directions of precision surgery in omPCa.

The impact of PSMA PET on the treatment and outcomes of men with biochemical recurrence of prostate cancer: a systematic review and meta-analysis

BACKGROUND

Prostate-specific membrane antigen (PSMA) PET is highly sensitive in identifying disease recurrence in men with biochemical recurrence of prostate cancer (BCR) after primary therapy and is rapidly being adopted in clinical practice. The purpose of this systematic review and meta-analysis was to assess the documented impact of PSMA-PET on patient management and outcomes, including prostate-specific antigen (PSA) response, and intermediate and long-term outcome measures.

MATERIALS AND METHODS

MBASE, PubMed, Web of Science, Cochrane and OVID databases were searched for studies reporting on the impact of PSMA-PET on the management and outcomes of patients with BCR after definitive primary therapy. Outcome measures assessed included biochemical response to therapy after PET and BCR-free survival (BRFS). The proportions of patients in whom management changed, and the proportion of patients in whom each outcome measure was obtained were tabulated and pooled into meta-analysis using DerSimonian-Laird method.

RESULTS

A total of 34 studies with 3680 men reported change in management after PSMA-PET and 27 studies with 2639 men reported on at least one outcome measure and had follow-up data. PSMA-PET was positive in 2508/3680 (68.2%). The pooled proportion of change in management after PSMA-PET was 56.4% (95% CI, 48.0-63.9%). A decrease in serum PSA was documented in 72.4% of men (95% CI, 63.4-81.5%), and complete biochemical response in 23.3% (95% CI, 14.6-32.0%) at a median follow-up of 8.1 and 11 months, respectively. The pooled BRFS rate was 60.2% (95% CI, 49.1-71.4%) at a median follow-up of 20 months.

CONCLUSION

In conclusion, PSMA PET is positive in more than 2/3 of men with BCR and impacts patient management in more than half of the men. BRFS after PET-directed management is 60% at a median of 20 months after salvage therapy, and complete biochemical response may be achieved in up to a quarter of men.

Salvage lymph node dissection for prostate-specific membrane antigen (PSMA) positron emission tomography (PET)-identified oligometastatic disease

INTRODUCTION

The availability of prostate-specific membrane antigen (PSMA) positron emission tomography (PET)/computed tomography (CT) imaging, particularly in the setting of rising prostate-specific antigen (PSA) after definitive treatment, has led to oligometastatic prostate cancer being increasingly identified. Despite the enthusiasm surrounding treating oligometastatic disease, it has been relatively understudied. We sought to review our salvage lymphadenectomy experience in the PSMA PET/CT era.

METHODS

We retrospectively reviewed patients undergoing lymphadenectomy following curative-intent primary therapy with rising PSA who had undergone a PSMA PET/CT identifying oligometastatic disease (defined as ≤5 PSMA-avid lesions) between January 2016 and April 2020. The primary endpoint was complete response, defined as achieving a PSA <0.2 ng/ml without concomitant androgen deprivation therapy (ADT).

RESULTS

Twenty-two patients were included. Primary curative therapy included radical prostatectomy (86.4%) and brachytherapy (13.6%). Median PSA at salvage surgery was 1.72 ng/ml. Pelvic lymph node dissection was the most performed procedure (72.7%). Median node yield was 10.5, with a median of 1.5 positive nodes on pathology. Eight patients (36.4%) achieved PSA <0.2, with six (27.3%) remaining with PSA <0.2 after a median followup of 23.1 months. Nine (40.9%) had an initial PSA decline, but nadired ≥0.2, and in five (22.7%) the PSA rose immediately after surgery. Overall, ADT was started in seven patients (31.8%) at a median of 10.1 months post-salvage surgery.

CONCLUSIONS

In our series of salvage dissection for PSMA-PET-detected nodal oligometastases, approximately a third achieved PSA <0.2; yet, it was only durable in 27%. Prospective trials of salvage nodal radiation are ongoing, however, more prospective trials of salvage node dissection are needed.

Patient-Reported and Oncological Outcomes of Salvage Therapies for PSMA-Positive Nodal Recurrent Prostate Cancer: Real-Life Experiences and Implications for Future Trial Design

Introduction

The role of salvage lymph node dissection (SLND) and radiotherapy (SLNRT) in the management of nodal-only recurrent prostate cancer (PC) remains controversial. In addition, impact on health-related quality of life (HRQOL) has not been adequately evaluated yet.

Materials and Methods

Analysis was limited to patients that were diagnosed with nodal-only recurrent PC via PSMA-PET/CT. SLND was performed via open approach. For SLNRT, dose regimens were normo- or slightly hypo-fractionated with a simultaneous boost to the PET-positive recurrences. EORTC QLQ-C30 and PR-25 questionnaires were used to assess HRQOL. Continence status was assessed using daily pad usage and the validated ICIQ-SF questionnaire. For multivariable analysis, Cox regression models were used (p<0.05).

Results

138 patients (SLND: 71; SLNRT: 67) were included in the retrospective analysis. Median follow-up was 47 months (mo) for SLNRT patients (IQR 40-61), and 33mo for SLND patients (IQR 20-49; p<0.001). In total, 61 patients (91.0%) in the SLNRT cohort and 43 patients (65.2%; p<0.001) in the SLND cohort underwent ADT anytime during the follow-up period. In multivariate Cox regression analysis, SLNRT could be confirmed as an independent predictor for increased PSA progression-free survival (PFS; HR 0.08, 95%CI 0.040 - 0.142, p<0.001). Estimated median metastasis-free survival (MFS) was 70mo for the total cohort without statistically significant differences between both subgroups (p=0.216). There were no significant differences regarding general HRQOL, daily pad usage, and ICIQ-SF scores between the respective cohorts.

Conclusions

In a large contemporary series of patients with nodal-only recurrent PC based on PSMA-PET/CT staging, we observed significantly increased PSA PFS in patients undergoing SLNRT while no significant differences could be observed in MFS, and functional outcomes including HRQOL.

Role of salvage lymph node dissection in patients previously treated for prostate cancer: systematic review

Prostate cancer is the most common invasive cancer in men. Radical prostatectomy (RP) is a definitive treatment option, but biochemical recurrence can reach 40%. Salvage lymphadenectomy is a relatively recent approach to oligometasis and has been rapidly diffused primarily due to improvement in imaging diagnosis and results showing possibly promising therapy. A systematic literature review was performed in March 2020, according to the PRISMA statement. We excluded studies with patients with suspicion or confirmation of visceral and / or bone metastases. A total of 27 articles were included in the study. All studies evaluated were single arm, and there were no randomized studies in the literature. A total of 1,714 patients received salvage lymphadenectomy after previous treatment for localized prostate cancer. RP was the most used initial therapeutic approach, and relapses were based on PET / CT diagnosis, with Coline-11C being the most widely used radiopharmaceutical. Biochemical response rates ranged from 0% to 80%. The 5 years - Free Survival Biochemical recurrence was analyzed in 16 studies with rates of 0% up to 56.1%. The articles do not present high levels of evidence to draw strong conclusions. However, even if significant rates of biochemical recurrence are not evident in all studies, therapy directed to lymph node metastases may present good oncological results and postpone the onset of systemic therapy. The long-term impact in overall survival and quality of life, as well as the best strategies for case selection remains to be determined.

Metastasis-directed therapy and prostate-targeted therapy in oligometastatic prostate cancer: a systematic review

INTRODUCTION

The aim of this review was to summarize the available evidence on the role of metastasis-directed therapy (MDT) and/or prostate-targeted therapy (PTT) in the setting of oligometastatic prostate cancer (PCa).

EVIDENCE ACQUISITION

We searched PubMed, the Web of Science, and the Cochrane Library databases. The following keywords were used: ("prostate cancer" OR "prostate carcinoma" OR "prostate neoplasm" OR "prostate tumor") AND ("oligometastatic" OR "oligometastasis" OR "PSMA") AND ("surgery" OR "prostatectomy" OR "radical prostatectomy" OR "cytoreductive" OR "local treatment" OR "radiotherapy" OR "stereotactic" OR "stereotaxic") AND ("survival" OR "mortality").

EVIDENCE SYNTHESIS

After evaluating the selection criteria, 81 studies were evaluated for our endpoints. We included 22 studies for PTT of synchronous mPCa. There have been no randomized studies on cytoreductive prostatectomy (cRP). Four prospective studies showed that cRP was feasible but did not contribute to a positive effect on overall survival (OS). Regarding PTT-radiotherapy, two randomized controlled phase 3 trials showed that OS was improved in men with a low metastatic burden. Regarding MDT of metachronous lymph node recurrence, we included 29 retrospective studies. For MDT of oligometastases, we included 30 studies. One randomized phase 2 trial showed that androgen deprivation therapy-free survival improved with stereotactic body radiation therapy compared to that with surveillance; however, benefits on OS remain unclear.

CONCLUSIONS

We performed a comprehensive overview of the current literature on MDT and PTT. The feasibility of MDT and PTT is supported by several retrospective studies. Nevertheless, there remains a lack of high-quality trials to prove its survival benefits. Results from ongoing prospective trials data are awaited.

Risk Factors for Pathologically Confirmed Lymph Nodes Metastasis in Patients With Clinical T2N0M0 Stage Prostate Cancer

Objective

To explore the risk factors for postoperatively pathological lymph node metastasis in patients with clinical T2N0M0 stage prostate cancer (PCa).

Methods

We retrospectively analyzed clinicopathological data of 316 patients with clinical T2 stage PCa and preoperative negative lymph nodes [LN(−)] indicated by imaging (cT2N0M0) between January 2014 and May 2019. Multivariate logistic regression analysis was performed to determine risk factors for postoperatively pathological pLN(+) in patients with cT2N0M0 stage PCa. Spearman correlation analysis was used to explore the relationship between tumor burden and Prostate Imaging Reporting and Data System version 2 (PI-RADS v2) score.

Results

A total of 45 patients (14.2%) were confirmed by postoperative pathology to have LN metastasis. Univariate analysis indicated that total prostate-specific antigen (tPSA), PI-RADS v2 score, postoperative Gleason grade group (GGG), intraductal carcinoma of the prostate (IDC-P), clinical T2 substaging, and postoperative pathological tumor burden were risk factors for pLN(+) in all patients. Multivariate analysis showed that tPSA and postoperative GGG were risk factors for pLN(+) in all patients. Univariate analysis revealed that tPSA, PIRADS v2 score, clinical T2 substaging, IDC-P, postoperative pathological tumor burden, and postoperative GGG were risk factors for pLN(+) in patients with GGG ≥ 3. Multivariate analysis suggested that tPSA, PI-RADS v2 score, clinical T2 substaging, postoperative pathological tumor burden, and GGG were risk factors for pLN (+) in patients with GGG ≥ 3. Spearman correlation analysis showed that PI-RADS v2 score was positively correlated with clinical T2 substaging and postoperative pathological tumor burden.

Conclusion

There was a high risk of LN metastasis in patients with cT2 PCa if they had high preoperative tPSA or high postoperative GGG. Patients with cT2 PCa and GGG ≥ 3 had a high risk of LN metastasis if they had high PI-RADS v2 score, high preoperative clinical stage or high postoperative pathological tumor burden. PI-RADS v2 score predicted tumor burden well in patients with GGG ≥ 3.

PSMA-positive nodal recurrence in prostate cancer : Salvage radiotherapy is superior to salvage lymph node dissection in retrospective analysis

PURPOSE

This analysis compares salvage lymph node dissection (SLND) to salvage lymph node radiotherapy (SLNRT) of ⁶⁸Ga-PSMA PET-positive nodal recurrences after radical prostatectomy (RPE).

METHODS

A total of 67 SLNRT and 33 SLND consecutive patients with pelvic and/or para-aortic nodal recurrences after RPE were retrospectively analyzed. Biochemical recurrence-free survival rates (bRFS; PSA <0.2 ng/mL) were calculated according to Kaplan-Meier and survival curves were compared using the log rank test. For multivariable analysis, binary logistic regression analysis was performed (p < 0.05).

RESULTS

Median follow-up was 17 months (range, 6-53 months) in SLND patients and 31 months (range, 3-56 months) in SLNRT patients (p = 0.027). SLNRT patients had significantly more tumours of pT3 and pT4 category (82% vs. 67%; p = 0.006), pathologically involved lymph nodes (45% vs. 27%; p = 0.001) and positive surgical margins (54% vs. 12%; p = 0.001) at time of RPE than SLND patients. PSA persistence after RPE was significantly more frequently observed in the SLNRT cohort (73% vs. 27%; p = 0.001). There was no significant difference in the distribution of PET-positive lymph nodes. Median PSA before SLND was higher than before SLNRT (3.07 ng/ml vs. 1.3 ng/ml; p = 0.393). The 2‑year bRFS was significantly higher in the SLNRT vs. the SLND cohort (92% vs. 30%; p = 0.001) with lower rates of distant metastases (21% vs. 52%; p = 0.002) and secondary treatments (5% vs. 39%; p = 0.011) irrespective of ongoing androgen deprivation therapy at last contact. In multivariable analysis, SLNRT was significantly associated with prolonged bRFS (regression coefficient 1.436, hazard ratio 4.204, 95% CI 1.789-9.878; p = 0.001).

CONCLUSION

Based on this retrospective study SLNRT might be the preferred treatment option for patients with nodal recurrence after previous RPE.

The Use of MRI and PET Imaging Studies for Prostate Cancer Management: Brief Update, Clinical Recommendations, and Technological Limitations

Multi-parametric magnetic resonance imaging (mpMRI) and positron emission tomography (PET) using prostate-specific membrane antigen (PSMA) targeting ligands have been adopted as a new standard of imaging modality in the management of prostate cancer (PCa). Technological advances with hybrid and advanced computer-assisted technologies such as MR/PET, MR/US, multi-parametric US, and robotic biopsy systems, have resulted in improved diagnosis and staging of patients in various stages of PCa with changes in treatment that may be considered “personalized”. Whilst newer clinical trials incorporate these novel imaging modalities into study protocols and as long-term data matures, patients should be made aware of the potential benefits and harm related to these technologies. Published literature needs to report longer-term treatment efficacy, health economic outcomes, and adverse effects. False positives and negatives of these imaging modalities have the potential to cause harm and the limitations of these technologies should be appreciated. The role of a multi-disciplinary team (MDT) and a shared-decision-making model are important to ensure that all aspects of the novel imaging modalities are considered.

[Oligometastatic prostate cancer management]

OBJECTIVE

To review biology and management of oligometastatic prostate cancer.

MATERIAL AND METHODS

Relevant publications were identified through Medline (www. ncbi.nlm.nih.gov), Embase (www.embase.com) and the US National Library of Medicine (www.clinicaltrials.org) databases using the following keywords, alone or in association, «prostate cancer; metastasis; oligo-metastasis». Articles were selected according to methods, language of publication and relevance. After careful selection 99 publications were eligible for our review.

RESULTS

Oligometastatic prostate cancer is a new entity including prostate cancer with a limited number of metastasis. This particular state becomes more frequent with the imaging progresses especially with the common use of new PET imaging with Choline or PSMA. There is no consensus about a strict definition of oligometastatic prostate cancer, number and sites of metastasis vary widely in the literature. Moreover, oligometastatic state can be observed de novo at the time of prostate cancer diagnosis as well as in case of recurrence after a primary treatment. There is actually an important lack of evidence-based medicine and no guidelines regarding treatment can be found. In de novo oligo-metatastatic prostate cancer, treatment of the primary tumor in association with androgen deprivation therapy seems to increase survival in selected patients but this needs to be confirmed by ongoing prospective clinical trials. In recurrent prostate cancer, metastasis directed therapy with or without androgen deprivation therapy is now routinely performed but its impact needs also to be analyzed.

CONCLUSION

In absence of consensus or guidelines, management of prostate cancer should be an individualized, patient-based management taking into account primary tumor stage and grade, number and types of metastasis and patient characteristics.

Salvage lymphadenectomy in recurrent prostate cancer: is there evidence of real benefit?

PURPOSE

Nodal recurrent prostate cancer (PCa) after primary radical treatment represents a heterogeneous entity with many treatment options. In some cases, surgical removal of metastatic nodes seems to improve cancer control and delay systemic treatments. The objectives of this study were to analyze the available literature on salvage lymphadenectomy for the treatment of nodal recurrent PCa and to elucidate the real oncological benefit deriving from this procedure.

METHODS

A PubMed search was performed using the following terms: prostate cancer, metastatic, oligometastatic, salvage lymphadenectomy, salvage lymph node dissection, salvage lymph node excision, and cytoreductive surgery. We included in the study all papers on salvage lymphadenectomy in nodal recurrent PCa, with no temporal limits. In addition, several papers addressing cytoreductive surgery and the biology of oligometastatic disease, published in different medical and basic research journals, were included.

RESULTS

Salvage lymphadenectomy is still characterized by a lack of standardization in patient selection and surgical template. Its primary objectives are to prolong progression-free survival and to delay the need for systemic therapy. The improvements in preoperative imaging techniques in conjunction with the wide use of minimally invasive surgery have generated growing interest in this procedure.

CONCLUSION

Salvage lymphadenectomy is a promising treatment approach; however, its real oncological benefit is still far from proven. Prospective randomized trials need to be designed to improve understanding of this issue.

Performance of [68Ga] Ga-PSMA 11 PET for detecting prostate cancer in the lymph nodes before salvage lymph node dissection: a systematic review and meta-analysis

BACKGROUND

Salvage lymph node dissection (sLND) for nodal recurrence in prostate cancer (PCa) patients with biochemical recurrence (BCR) is still not recommended in current guidelines, because of the diagnostic inaccuracy of current conventional imaging. To assess the performance of [⁶⁸Ga] Ga-prostate-specific membrane antigen conjugate 11 positron emission tomography (PSMA-PET) in detecting PCa lymph node metastasis using pathologic confirmation through sLND.

METHODS

Literature search was conducted using the MEDLINE, SCOPUS, Web of Science, and Cochrane Library on November 11th, 2018 to identify the eligible studies. Studies were eligible if they investigated the diagnostic performance of PSMA-PET before sLND in PCa patients with BCR and reported the number of true positive, false positive, false negative, and true negative on a lesion-based and/or field-based analyses to compare with histopathologic findings in sLND specimens.

RESULTS

Fourteen studies published between 2015 and 2018 comprising 462 patients were selected in this systematic review and meta-analysis. The positive predictive value of PSMA-PET before sLND on a patient-based analysis ranged between 0.70 and 0.93. The pooled sensitivity using lesion-based and field-based analyses were 0.84 (95%CI: 0.61-0.95) and 0.82 (95%CI: 0.72-0.89), respectively. The pooled specificity using lesion-based and field-based analyses were 0.97 (95%CI: 0.95-0.99) and 0.95 (95%CI: 0.70-0.99), respectively. The diagnostic odds ratio using lesion-based and field-based analyses were 189 (95%CI: 39-920) and 82 (95%CI: 8-832), respectively.

CONCLUSIONS

PSMA-PET before sLND provided highly accurate performance with clinically relevant high positive and negative predictive values for detecting lymph node disease in patients with BCR after local treatment with curative intent for PCa. PSMA-PET can identify the patients who are likely to benefit from sLND and possibly direct to lesion or region-based dissection.

Circulating Tumor Cells as a Predictor of Treatment Response in Clinically Localized Prostate Cancer

PURPOSE

Using nonenrichment-based, potentially more sensitive Epic Sciences circulating tumor cell (CTC) platform, we sought to detect and characterize CTCs in untreated, high-risk localized prostate cancer and to evaluate their clinical implication.

METHODS

Between 2012 and 2015, blood samples were prospectively collected from patients with National Comprehensive Cancer Network high-risk localized prostate cancer undergoing either radiotherapy (XRT) plus androgen deprivation therapy or radical prostatectomy (RP) with curative intent. Samples were analyzed with the Epic Sciences platform with 4^J,6-diamidino-2-phenylindole, CD45, cytokeratin (CK), and androgen receptor (AR) N-terminal staining. CTC counts were correlated with biochemical recurrence (BCR).

RESULTS

A diversity of CTC subtypes, including CK-positive, CK-negative, AR-positive, and CTC clusters, were observed in 73.3% (33 of 45) of patients with evaluable data. The median follow-up was 14.2 months (range, 0.5 to 43.7 months). BCR occurred more frequently in the RP group than XRT (15 of 26 v one of 19), with most patients in the XRT group continuing to receive androgen deprivation therapy. A higher proportion of metastatic events were observed in the RP group (five of 26 v one of 19). In the RP group, BCR and development of metastases were associated with a higher total number of CTCs, AR-positive CTCs, and CTC phenotypic heterogeneity. One patient who developed BCR and metastases quickly after RP had diverse phenotypical CTC subtypes, and single-cell genomic analyses of all detectable CTCs confirmed common prostate cancer copy number alterations and PTEN loss.

CONCLUSION

CTCs can be identified in most patients with high-risk localized prostate cancer before definitive therapy using the Epic Sciences platform. If confirmed in a larger cohort with longer follow-up, phenotypic and genomic characterization of CTCs pretherapy may provide an additional means of risk stratifying patients with newly diagnosed high-risk disease and potentially help identify patients who could require multimodal therapy.

Single Lesion on Prostate-specific Membrane Antigen-ligand Positron Emission Tomography and Low Prostate-specific Antigen Are Prognostic Factors for a Favorable Biochemical Response to Prostate-specific Membrane Antigen-targeted Radioguided Surgery in Recurrent Prostate Cancer

BACKGROUND

Prostate-specific membrane antigen (PSMA)-ligand positron emission tomography (PET) allows detection of metastatic prostate cancer (PC) lesions at low prostate-specific antigen (PSA) values. To facilitate their intraoperative detection during salvage surgery, we recently introduced PSMA-targeted radioguided surgery (RGS).

OBJECTIVE

To describe the outcome of a large cohort of patients treated with PSMA-targeted RGS and to establish prognostic factors.

DESIGN, SETTING, AND PARTICIPANTS

A total of 121 consecutive patients with recurrent PC as defined by PSMA-ligand PET (median PSA: 1.13ng/ml) underwent PSMA-targeted RGS.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

The frequency of a complete biochemical response (cBR; PSA <0.2ng/ml) without additional treatment and the duration of biochemical recurrence-free survival (bRFS, time from PSMA-targeted RGS with PSA <0.2ng/ml without further treatment) were evaluated and correlated with preoperatively available clinical variables.

RESULTS AND LIMITATIONS

In almost all patients (120/121, 99%) metastatic tissue could be removed. A cBR was achieved in 77 patients (66%). The chance of cBR was highest in patients with both low preoperative PSA and a single lesion (38/45: 84%). Median bRFS was 6.4mo in the whole patient cohort and 19.8mo for patients with cBR. Significantly longer median bRFS was observed in patients with a low preoperative PSA value (p=0.004, hazard ratio 1.48, 95% confidence interval 1.13-1.93) and with a single lesion in preoperative PSMA-ligand PET (14.0 vs 2.5mo, p=0.002).

CONCLUSIONS

PSMA-targeted RGS leads to a remarkable interval of bRFS in a subset of patients. The frequency of cBR and the duration of bRFS were highest in patients with a low preoperative PSA value and a single lesion on PSMA-ligand PET.

PATIENT SUMMARY

Prostate-specific membrane antigen radioguided surgery delays disease progression in selected patients with recurrent prostate cancer after radical prostatectomy. Patients with a single lesion of recurrence and a low prostate-specific antigen value had the best outcome.

177Lu-PSMA radioligand therapy of predominant lymph node metastatic prostate cancer

¹⁷⁷Lu-PSMA radioligand therapy (LuPRLT) is mainly used for patients with metastatic castration-resistant prostate cancer who are resistant to established drugs. This study describes LuPRLT, either LuPSMA I&T or LuPSMA RLT-617, for 45 patients with predominant lymph node metastatic prostate cancer (LNM PC). Thirty-five patients had LNM and ten patients had LNM and one or two bone metastases. Before LuPRLT, the patients had prostate specific antigen (PSA) of median 18 µg/l (interquartile range (IQR): 3.3–39). LuPRLT was given with a cumulative injected ¹⁷⁷Lu activity of median 14.5 GBq (IQR: 12.2–20.4). Maximum percentage decline of PSA was median 92% (IQR: 70–99). Thirty-five patients with only LNM had a better overall survival (OS) than ten patients with LNM and one or two bone metastases. Thirty-three docetaxel-naïve patients had a longer PSMA PET/CT progression-free survival than twelve patients who were resistant to docetaxel. Twenty-two patients who received LuPRLT with a cumulative injected ¹⁷⁷Lu activity ≥ 14.8 GBq had a better PSMA PET/CT progression-free survival than 23 patients who received LuPRLT with a lower cumulative injected ¹⁷⁷Lu activity. Seventeen patients with relapse after LuPRLT who received rechallenge LuPRLT or ActPRLT had a better OS than five patients who received other forms for relapse treatment. LuPRLT gave mild and transitory adverse effects. The findings of the present study suggest that LuPRLT of patients with LNM may be effective and safe. The promising results motivate randomized phase II trials to further quantify the impact of LuPRLT as treatment of patients with LNM.

Metaanalysis of 68Ga-PSMA-11 PET Accuracy for the Detection of Prostate Cancer Validated by Histopathology

⁶⁸Ga-PSMA-11 PET is used to stage patients with prostate cancer. We performed an updated metaanalysis that separates imaging at the time of diagnosis and at the time of biochemical recurrence and focuses on pathology correlation in both populations. Methods: We searched the MEDLINE and EMBASE databases using the PRISMA statement. Quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies tool 2. In total, 1,811 studies were screened, 58 were analyzed, 41 were included for qualitative synthesis, and 29 were included for quantitative analysis. A random-effect model and a hierarchical summary receiver-operating-characteristic model were used to summarize the sensitivity, specificity, positive predictive value (PPV), negative predictive value, and accuracy for pelvic lymph nodes in initial staging compared with pathology at prostatectomy and the PPV for lesions with pathologic correlation in those with biochemical recurrence. We also summarized the detection rate of ⁶⁸Ga-PSMA-11 in those with biochemical recurrence stratified by prostate-specific antigen (PSA) at the time of imaging. Results: The metaanalysis of ⁶⁸Ga-PSMA-11 at initial staging demonstrated a sensitivity and specificity of 0.74 (95% confidence interval [95% CI], 0.51-0.89) and 0.96 (95% CI, 0.85-0.99), respectively, using nodal pathology at prostatectomy as a gold standard. At biochemical recurrence, the PPV was 0.99 (95% CI, 0.96-1.00). The detection rate was 0.63 (95% CI, 0.55-0.70), with a PSA of less than 2.0 and 0.94 (95% CI, 0.91-0.96) with a PSA of more than 2.0. Conclusion: ⁶⁸Ga-PSMA-11 performed well for the localization of metastatic prostate cancer at initial staging and at the time of biochemical recurrence.

Prostate specific membrane antigen: the role in salvage lymph node dissection and radio-ligand therapy

INTRODUCTION

Prostate-specific membrane antigen (PSMA) is a receptor highly expressed on the membranes of prostate cancer (PCa) cells and provides a new opportunity for imaging and targeted therapy in metastatic prostate cancer. The use of radio-labelled peptides with high affinity for PSMA-receptor allows for localization of oligo-metastasis to guide salvage lymph node (LN) dissection, and effective delivery of radionuclide therapy to PCa cells. This review discusses the current statistics of PSMA-guided salvage lymph-node dissection.

EVIDENCE ACQUISITION

A non-systematic literature search of the Medline, Embase, and Scopus databases was performed in December 2017 using medical subject headings and free-text protocol.

EVIDENCE SYNTHESIS

The properties of PSMA has enabled the timely detection of oligometastatic disease, potentially altering oncological outcomes of men with PCa. The utility of PSMA in directing sLND has been proven to have an impact in achieving modest biochemical response which is generally not durable.

CONCLUSIONS

Larger randomized controlled trials are needed to validate the current findings, determine treatment protocols, and weigh up its benefits and determine its standing amongst the current management strategies for PCa.

Prognostic value of 68 Ga PSMA I&T PET/CT SUV parameters on survival outcome in advanced prostat cancer

OBJECTIVE

To determine the association of 68 Ga-PSMA-I&T PET/CT SUV parameters with survival outcome in advanced prostate cancer patients.

METHODS

A total of 148 consecutive patients mean age: 69.3 ± 7.8 years with advanced prostate cancer who underwent 68 Ga-PSMA-I&T PET/CT were included in this retrospective study. Data on previous treatments, serum PSA levels (ng/mL), 68 Ga-PSMA-I&T PET/CT findings metastases as well as survival data were recorded.

RESULTS

Multivariate regression analysis revealed that Level 1 LN SUV/Liver SUV ratios > 2.17 (OR 4.262; 95% CI 1.104-16.453, p = 0.035), bone SUV > 10.7(OR 23.650; 95% CI 4.056-137.888, p < 0.001), bone SUV/spleen SUV ratio > 1.842 (OR 25.324; 95% CI 4.204-152.552, p < 0.001), highest SUV_max/liver SUV ratio > 2.32 (OR 19.309; 95% CI 1.730-209.552, p = 0.016) and highest SUV_max/spleen SUV ratio > 1.842 (OR 22.354; 95% CI 2.637-189.493, p = 0.004) were significant in the determination of increased mortality risk in advanced prostate cancer patients.

CONCLUSION

Our findings, for the first time in literature, provided evidence on potential utility of tracer uptake (SUV) cut-off values on 68 Ga-PSMA PET/CT in identification of the survival outcome of patients with metastatic disease and thereby in assisting in the selection of individualized therapeutic strategies tailored to the expected prognosis.

Oligometastatic prostate cancer and salvage lymph node dissection: systematic review

INTRODUCTION

We provide a comprehensive description of the physio-pathological theories behind oligometastatic prostate cancer (PCa) and analyze modern imaging techniques, presenting a systematic review of the available evidences regarding salvage lymph node dissection (sLND).

EVIDENCE ACQUISITION

A systematic review was attempted. The PubMed/Medline database was searched for "salvage" AND ("lymph node dissection" OR "lymphadenectomy") AND "prostate" AND "cancer." Only English publications were targeted. Relevant original articles addressing the role of sLND in PCa were selected.

EVIDENCE SYNTHESIS

Biochemical response (BR) was reported in 10-79.5% of the cases overall. These results were not durable and biochemical recurrence occurred in 54.5-93.8% of the cases, within 5 years. Furthermore, 50-80% of patients received some kind of adjuvant treatment right after sLND, regardless post-operative prostate-specific antigen levels. Surgery-related morbidity was low, with a 0-27% incidence of Clavien-Dindo III complications. No sLND-related deaths were observed.

CONCLUSIONS

sLND is not associated with a durable response over time but may postpone HT and its related complications, in selected patients. Although a limited morbidity was reported, sLND remains technically demanding and a careful selection of patients is advisable.

Review of Gallium-68 PSMA PET/CT Imaging in the Management of Prostate Cancer

Over 90% of prostate cancers over-express prostate specific membrane antigen (PSMA) and these tumor cells may be accurately targeted for diagnosis by 68Ga-PSMA-positron emission tomography/computed tomography (68Ga-PSMA-PET/CT) imaging. This novel molecular imaging modality appears clinically to have superseded CT, and appears superior to MR imaging, for the detection of metastatic disease. 68Ga-PSMA PET/CT has the ability to reliably stage prostate cancer at presentation and can help inform an optimal treatment approach. Novel diagnostic applications of 68Ga-PSMA PET/CT include guiding biopsy to improve sampling accuracy, and guiding surgery and radiotherapy. In addition to facilitating the management of metastatic castrate resistant prostate cancer (mCRPC), 68Ga-PSMA can select patients who may benefit from targeted systemic radionuclide therapy. 68Ga-PSMA is the diagnostic positron-emitting theranostic pair with the beta emitter Lutetium-177 PSMA (177Lu-PSMA) and alpha-emitter Actinium-225 PSMA (225Ac-PSMA) which can both be used to treat PSMA-avid metastases of prostate cancer in the molecular tumor-targeted approach of theranostic nuclear oncology.