The Role of C-Choline-PET/CT-Guided Secondary Lymphadenectomy in Patients with PSA Failure after Radical Prostatectomy: Lessons Learned from Eight Cases

Prostate-specific membrane antigen-radioguided surgery salvage lymph node dissection: experience with fifty oligorecurrent prostate cancer patients

PURPOSE

The higher detection efficacy of PSMA PET for oligometastatic recurrence of prostate cancer has promoted new loco-regional treatment options. PSMA-targeted radioguided surgery (PSMA-RGS) was introduced to facilitate salvage surgery of small tumor deposits. The objectives of this retrospective analysis are to describe an independent single-center consecutive cohort of patients undergoing PSMA-RGS and to evaluate its clinical and oncological outcomes.

METHOD

Between 2018 and 2022, 53 patients were treated with PSMA-RGS and 50 patients were available for final analyses. All patients were initially treated with radical prostatectomy (RP) and presented with biochemical recurrence (BCR) with at least one positive lesion on PSMA-PET imaging. After preparation of 99mTc-PSMA-I&S and intravenous injection, surgery was performed by using a gamma-probe intraoperatively.

RESULTS

Median age was 70 years (IQR 65-73) and the median PSA at salvage surgery was 1.2 ng/mL (IQR 0.6-3.0). In all patients pathologically positive lesions could be removed during PSMA-RGS. 29 (58%) patients had one pathologically positive lesion, 14 (28%) had two and 7 (14%) had three or more, respectively. The overall complication rate was 26% with 4 (8%), 1 (2%), and 8 (16%) having Clavien-Dindo (CD) type I, II, and IIIb complications, respectively. During the follow-up period 31 (62%) patients experienced BCR and 29 (58%) received further therapy.

CONCLUSIONS

PSMA-RGS is a promising treatment option to enhance salvage surgery in early biochemical recurrence. However, only 42% of the patients treated with PSMA RGS remain without a biochemical recurrence. Further research is mandatory to identify patients, who profit from PSMA-RGS.

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.

Anatomical mapping of lymph nodes in patients receiving salvage lymphadenectomy based on a positive 11C-choline positron emission tomography/computed tomography scan

INTRODUCTION

This paper aims to assess the diagnostic accuracy of an 11C-choline positron emission tomography/computed tomography (PET/CT) scan in the detection of lymph node (LN) metastases in patients with biochemical recurrence after radically treated prostate cancer (PCa), as compared to histology. The secondary goal is to depict spreading patterns of metastatic LNs in recurrent PCa.

MATERIAL AND METHODS

A single center retrospective study comprising of 30 patients who underwent retroperitoneal and/or pelvic salvage lymph node dissection (LND) due to 11C-choline PET/CT-positive nodal recurrences after radical treatment (median Prostate Specific Antigen (PSA) 1.5 ng/ml, range 0.2-11.4). Positive nodes on the preoperative PET/CT scans were mapped and compared to post-operative pathology results.LNs were marked as true positive, false positive, true negative and false negative and a patient- and a region-based analysis was performed. Sensitivity, specificity and positive/negative predictive value (PPV/NPV) were calculated.

RESULTS

Sixty positive LNs were detected on PET/CT with a median number of two positive nodes per patient (range 1-6). In 29 patients, a super-extended pelvic LND (PLND) was performed combined with a retroperitoneal LND (RPLND) in 13 of those cases. One patient underwent an inguinal LND. One hundred thirty-seven of 644 resected LNs contained metastases. The 11C-choline PET/CT scan correctly predicted 31 positive nodes (55%) while 25 nodes were falsely positive (45%). One hundred and six histologically proven metastatic nodes were not detected on the 11C-choline PET/CT scan (77%). Sensitivity, specificity, PPV and NPV of the 11C-choline PET/CT were 23%, 95%, 55% and 82%, respectively.

CONCLUSIONS

11C-choline PET/CT has a relatively low detection rate and a moderate PPV for metastatic LNs in patients with biochemical recurrence after radically treated PCa.

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.

Role of salvage lymph node dissection in prostate cancer

PURPOSE OF REVIEW

Oligometastatic prostate cancer (PCA) has increasingly been detected in the era of modern imaging studies such as choline-specific and prostate-specific membrane antigen (PSMA)-positron emission tomography and X-ray computed tomography (PET/CT). Recent evidence suggests that durable control is attainable with local treatment modalities such as salvage metastasectomy or stereotactic radiation therapy targeting oligometastases, either with or without the use of systemic therapy. The purpose of this article is to critically review the current findings on the indication, extent, and oncologic outcome of salvage lymphadenectomy (SLAD).

RECENT FINDINGS

Oligometastatic PCA is defined by three or less to five metastatic lesions, no rapid spread to more sites, and feasibility of targeted treatment of all metastatic lesions with surgery or radiation therapy. Ga-PSMA-PET/CT or C-choline PET/CT represents the imaging study of choice to identify patients with potential lymph node metastases, and both studies should be performed at prostate-specific antigen serum levels around 1 ng/ml in order to achieve optimal results. If available, Ga-PSMA-PET/CT should be preferred because of higher sensitivity, specificity, and accuracy. With regard to pelvic SLAD, only data of retrospective studies with a total of more than 400 patients and an evidence level III-IV are available. SLAD should always be performed in terms of an extended lymph node dissection. Five-year biochemical-free survival ranges between 19 and 25%, 5-year cancer-specific survival varies between 75 and 90%. The median time to systemic treatment is in the range of 20-30 months. Patients with retroperitoneal metastases have a poorer prognosis with less than 10% responding.

SUMMARY

SLAD in oligometastatic PCA represents an individual approach with the major goal to prolong progression-free survival and time until systemic therapy is started. It is currently unclear whether SLAD will have an impact on long-term survival. Prospective randomized trials targeting this issue are on their way.

The role of salvage extended lymph node dissection in patients with rising PSA and PET/CT scan detected nodal recurrence of prostate cancer

BACKGROUND

Non-prostatic bed recurrence of prostate cancer (PCa) is usually treated with androgen deprivation therapy (ADT). We analyzed the impact of salvage extended lymph node dissection (sLND) on cancer control in patients with rising PSA and lymph node (LN) metastases.

METHODS

Between 2009 and 2016 we performed sLND in 87 patients with biochemical recurrence (BCR) and positive LNs on ¹⁸FEC and ⁶⁸Ga-PSMA positron emission tomography/X-ray computer tomography (PET/CT) after primary treatment (PT) of PCa. Intra- and postoperative complications according to Clavien-Dindo were assessed and the rates of biochemical response (BR), BCR-free and clinical recurrence (CR)-free survival, as well as time to initiation of systemic treatment were evaluated.

RESULTS

Mean age of patients and mean PSA at sLND was 66.7 years (46-80 years) and 2.63 ng ml^-1 (1.27-3.75 ng ml^-1), respectively. With 87.4% radical prostatectomy (RP) was the most common PT. In all, 57.9% of patients additionally underwent adjuvant/salvage radiation therapy (RT) and 18.4% received ADT before sLND. Complete BR (cBR) was diagnosed in 27.5% of patients and incomplete BR in 40.6%. In total, 62.2% of patients remained without ADT at follow-up. With a median follow-up of 21 months (1-75 months), the cancer-specific mortality rate was 3.7%. The 3-year BCR-free, systemic therapy-free and CR-free survival rates for patients with cBR were 69.3%, 77.0% and 75%, respectively.

CONCLUSIONS

sLND can be performed without significant complications and achieves an immediate BR, thus allowing a significant postponement of systemic therapy in selected patients with BCR and nodal recurrence of PCa. Therefore, sLND following ⁶⁸Ga-PSMA PET/CT should be considered as part of a multimodal diagnostic and treatment concept for selective patients.

Management of Node Only Recurrence after Primary Local Treatment for Prostate Cancer: A Systematic Review of the Literature

PURPOSE

We analyzed all available studies assessing the management of node only recurrence after primary local treatment of prostate cancer.

MATERIALS AND METHODS

We systematically reviewed the literature in January 2015 using the PubMed, Web of Sciences and Embase databases according to PRISMA guidelines. Studies exclusively reporting visceral or bone metastatic disease were excluded from analysis. Eight radiotherapy and 12 salvage lymph node dissection series were included in our qualitative study.

RESULTS

All 248 radiotherapy and 480 salvage lymph node dissection studies were single arm case series including a total of 728 patients. Choline positron emission tomography/computerized tomography was the reference imaging technique for nodal recurrence detection. Globally 50% of patients remained disease-free after short-term followup. Nevertheless, approximately two-thirds of patients received adjuvant hormone therapy, leading an overestimation of prostate specific antigen-free survival rates obtained after salvage treatment. Combining radiotherapy with salvage lymph node dissection may improve oncologic control in the treated region without improving the outfield relapse risk or the prostate specific antigen response. Great heterogeneity among series in adjuvant treatments, endpoints, progression definitions and study populations made it difficult to assess the precise impact of salvage treatment on the prostate specific antigen response and compare outcomes between radiotherapy and salvage lymph node dissection series. Toxicity after radiotherapy or salvage lymph node dissection was acceptable without frequent high grade complications. The benefit of early hormone therapy as the only salvage treatment remains unknown.

CONCLUSIONS

Although a high level of evidence is currently missing to draw any strong conclusion, published clinical series show that in select patients salvage treatment directed to nodal recurrence could lead to good oncologic outcomes. Although the optimal timing of androgen deprivation therapy in this setting is still unknown, such an approach could delay time to systemic treatment with an acceptable safety profile. Future prospective trials are awaited to better clarify this potential impact on well-defined endpoints.

Targeted salvage lymphadenectomy in patients treated with radical prostatectomy with biochemical recurrence: complete biochemical response without adjuvant therapy in patients with low volume lymph node recurrence over a long-term follow-up

Background

Choline positron emission tomography/computed tomography (PET/CT) represents an option in restaging of prostate cancer patients with disease relapse after local treatment. The present study assess whether salvage resection of lymph node metastases detected on choline PET/CT imaging in prostate cancer patients with biochemical recurrence after radical prostatectomy can result in a long-term complete biochemical remission, without adjuvant therapy.

Methods

We analysed 13 patients with prostate specific antigen (PSA) recurrence (PSA median 1.64 ng/ml, range 0.5-9.55) after radical prostatectomy and suspicious lymph nodes (median 1; range 1–3) detected on [11C]choline and [18F]fluoroethylcholine PET/CT scans. An open salvage lymphadenectomy of positive lymph nodes in a PET/CT scan and nearby lymph nodes was carried out. We examined PSA outcome without adjuvant therapy; defined complete biochemical remission as PSA <0.01 ng/ml. Histological and PET/CT findings were compared.

Results

Ten of 11 patients with histologically confirmed lymph node metastases showed a PSA response. Three of ten patients with single lymph node metastases had a complete biochemical remission (median follow-up 72 months, range 31.0-83). In five cases with single lymph node metastasis PSA decreased <0.02 ng/ml. Histologically confirmed 13 of 16 metastasis suspicious lymph nodes. No lymph node metastases were detected in two patients. All of the additionally removed 30 lymph nodes were correctly negative.

Conclusions

This is the first confirmation of a complete biochemical remission after PET/CT guided secondary resection of a single lymph node metastasis in prostate cancer patients with biochemical recurrence after radical prostatectomy, over the long-term (>6.5 years), without adjuvant therapy. In order to improve these promising results, longer-term studies with more patients are required.

Salvage pelvic lymph node dissection in recurrent prostate cancer: surgical and early oncological outcome

Methodology. Seventeen patients with prostate-specific antigen (PSA) rise following local treatment for prostate cancer with curative intent underwent open or minimally invasive salvage pelvic lymph node dissection (SLND) for oligometastatic disease (<4 synchronous metastases) or as staging prior to salvage radiotherapy. Biochemical recurrence after complete biochemical response (cBR) was defined as 2 consecutive PSA increases >0,2 ng/mL; and after incomplete biochemical response as 2 consecutive PSA rises. Newly found metastasis on imaging defined clinical progression (CP). Palliative androgen deprivation therapy (ADT) was initiated if >3 metastases were detected or if patients became symptomatic. Kaplan-Meier statistics were applied. Results. Clavien-Dindo grade 1, 2, 3a, and 3b complications were seen in 6, 1, 1, and 2 patients, respectively. Median follow-up time was 22 months. Among 13 patients treated for oligometastatic disease, 8 (67%) had a PSA decline, with 3 patients showing cBR. Median PSA progression-free survival (FS) was 4.1 months and median CP-FS 7 months. Three patients started ADT, resulting in a 2-year ADT-FS rate of 79.5%. Conclusion. SLND is feasible, but postoperative complication rate seems higher than that for primary LND. Biochemical and clinical response duration is limited, but as part of an oligometastatic treatment regime it can defer palliative ADT.

Metastasis-directed therapy of regional and distant recurrences after curative treatment of prostate cancer: a systematic review of the literature

CONTEXT

The introduction of novel imaging modalities has increased the detection of oligometastatic prostate cancer (PCa) recurrence, potentially justifying the use of a metastasis-directed therapy (MDT) with surgery or radiotherapy (RT) rather than a systemic approach.

OBJECTIVE

To perform a systematic review of MDT for oligometastatic PCa recurrence.

EVIDENCE ACQUISITION

This systematic review was performed according to Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines. We searched the Medline and Embase databases from 1946 to February 2014 for studies reporting on biochemical or clinical progression and/or toxicity or complications of MDT (RT or surgery). Reports were excluded if these end points could not be ascertained or separately analysed, or if insufficient details were provided. Methodological quality was assessed using an 18-item validated quality appraisal tool for case series.

EVIDENCE SYNTHESIS

Fifteen single-arm case series reporting on a total of 450 patients met the inclusion criteria. Seven studies were considered of acceptable quality. Oligometastatic PCa recurrence was diagnosed with positron emission tomography with coregistered computed tomography in most of the patients (98%). Nodal, bone, and visceral metastases were treated in 78%, 21%, and 1%, respectively. Patients were treated with either RT (66%) or lymph node dissection (LND) (34%). Adjuvant androgen deprivation was given in 61% of patients (n=275). In the case of nodal metastases, prophylactic nodal irradiation was administered in 49% of patients (n=172). Overall, 51% of patients were progression free 1-3 yr after salvage MDT, with most of them receiving adjuvant treatment. For RT, grade 2 toxicity was observed in 8.5% of patients, with one case of grade 3 toxicity. In the case of LND, 11% and 12% of grade 2 and grade 3 complications, respectively, were reported.

CONCLUSIONS

MDT is a promising approach for oligometastatic PCa recurrence, but the low level of evidence generated by small case series does not allow extrapolation to a standard of care.

PATIENT SUMMARY

We performed a systematic review to assess complications and outcomes of treating oligometastatic prostate cancer recurrence with surgery or radiotherapy. We concluded that although this approach is promising, it requires validation in randomised controlled trials.

Evaluation of 11C-choline PET/CT for primary diagnosis and staging of urothelial carcinoma of the upper urinary tract: a pilot study

Purpose

We conducted a pilot study to prospectively evaluate the efficacy of PET/CT with ¹¹C-choline (choline PET/CT) for primary diagnosis and staging of urothelial carcinoma of the upper urinary tract (UUT-UC).

Methods

Enrolled in this study were 16 patients (9 men, 7 women; age range 51 – 83 years, mean ± SD 69 ± 10.8 years) with suspected UUT-UC. The patients were examined by choline PET/CT, and 13 underwent laparoscopic nephroureterectomy and partial cystectomy. Lymphadenectomy and chemotherapy were also performed as necessary in some of the patients. Of the 16 patients, 12 were confirmed to have UUT-UC (7 renal pelvis carcinoma and 5 ureteral carcinoma), 1 had malignant lymphoma (ureter), 1 had IgG4-related disease (ureter), and 2 had other benign diseases (ureter).

Results

Of the 16 study patients, 13 showed definite choline uptake in urothelial lesions, and of these, 11 had UUT-UC, 1 had malignant lymphoma, and 1 had IgG4-related disease. Three patients without choline uptake comprised one with UUT-UC and two with benign diseases. Of the 12 patients with UUT-UC, 3 had distant metastases, 2 had metastases only in the regional lymph nodes, and 7 had no metastases. Distant metastases and metastases in the regional lymph nodes showed definite choline uptake. The outcome in patients with UUT-UC, which was evaluated 592 – 1,530 days after surgery, corresponded to the patient classification based on the presence or absence of metastases and locoregional or distant metastases. Choline uptake determined as SUVmax 10 min after administration was significantly higher than at 20 min in metastatic tumours of UUT-UC (p < 0.05), whereas there was no statistically significant difference between the SUVmax values at 10 and those at 20 min in primary tumours of UUT-UC.

Conclusion

This study suggests that choline PET/CT is a promising tool for the primary diagnosis and staging of UUT-UC.

Contemporary role of salvage lymphadenectomy in patients with recurrence following radical prostatectomy

CONTEXT

Prostate cancer (PCa) patients with isolated clinical lymph node (LN) relapse, limited to the regional and/or retroperitoneal LNs, may represent a distinct group of patients who have a more favorable outcome than men with progression to the bone or to other visceral organs. Some data indirectly denote a beneficial impact of pelvic LN dissection on survival in these patients.

OBJECTIVE

To provide an overview of the currently available literature regarding salvage LN dissection (SLND) in PCa patients with clinical relapse limited to LNs after radical prostatectomy (RP).

EVIDENCE ACQUISITION

A systematic literature search was conducted using the Medline, Embase, and Web of Science databases to identify original articles, review articles, and editorials regarding SLND. Articles published between 2000 and 2012 were reviewed and selected with the consensus of all the authors.

EVIDENCE SYNTHESIS

Contemporary imaging techniques, such as 11C-choline positron emission tomography and diffusion-weighted magnetic resonance imaging, appear to enhance the accuracy in identifying LN relapse in patients with biochemical recurrence (BCR) and after RP. In these individuals, SLND can be considered as a treatment option. The currently available data suggest that SLND can delay clinical progression and postpone hormonal therapy in almost one-third of the patients, although the majority will have BCR. An accurate and attentive preoperative patient selection may help improve these outcomes. The most frequent complication after SLND was lymphorrhea (15.3%), followed by fever (14.5%) and ileus (11.2%). It is noteworthy that all examined cohorts originated from retrospective single-institution series, with limited sample size and short follow-up. Consequently, the current findings cannot be generalized and warrant further investigation in future prospective trials.

CONCLUSIONS

The current data suggest that SLND represents an option in patients with disease relapse limited to the LNs after RP; however, more robust data derived from well-designed clinical trials are needed to validate the role of SLND in this selected patient population.

PATIENT SUMMARY

Salvage lymph node dissection (SLND) represents a treatment option in for patients with prostate cancer relapse limited to the lymph nodes; however, more robust data derived from well-designed clinical trials are needed to validate the role of SLND in this selected patient population.

Salvage therapy of small volume prostate cancer nodal failures: a review of the literature

New imaging modalities may be useful to identify prostate cancer patients with small volume, limited nodal relapse ("oligo-recurrent") potentially amenable to local treatments (radiotherapy, surgery) with the aim of long-term control of the disease, even in a condition traditionally considered prognostically unfavorable. This report reviews the new diagnostic tools and the main published data about the role of surgery and radiation therapy in this particular subgroup of patients.

Salvage radiotherapy for prostate cancer: Finding a way forward using radiobiological modeling

PURPOSE

Recent modeling efforts, based on reported outcomes following salvage radiotherapy (SRT) for prostate cancer, predict the likelihood of biochemical control (tumor control probability, TCP) as a function of pre-treatment prostate specific antigen (PSA) and SRT dose. Similar instruments predict the risk of grade ≥ 3 late toxicity (normal tissue complication probability, NTCP) as a function of SRT dose. Here we explore how changes in the parameters of those models might affect the optimal SRT dose and clinical outcomes.

MATERIALS AND METHODS

Baseline TCP and NTCP model parameters were established in a previous report. Pre-treatment PSA was set at 0.4 ng/mL. Model parameters were modified to explore four scenarios: (1) improving the safety of SRT, (2) increasing tumor cell radiosensitivity, (3) increasing the cure rate achievable with SRT and (4) adoption of hypofractionated SRT schedules. The "optimal" SRT dose, defined as the dose that maximized the likelihood of achieving biochemical control without causing late toxicity, was identified for each scenario.

RESULTS

Improving the safety of SRT increased the optimal SRT dose, while radiosensitization decreased the optimal dose. Both changes were predicted to increase the probability of biochemical control and decrease late toxicity rates. Increasing the cure rate achievable with SRT (eg: improving patient selection or combining SRT with effective systemic therapy) provided the greatest gains in TCP. Adoption of a hypofractionated SRT schedule was predicted to improve both biochemical control and late toxicity.

CONCLUSIONS

Modeling exercises demonstrate the significant gains that may be achieved with improved implementation of SRT for prostate cancer. Strategies to realize the effects modeled in this report should be explored in clinical trials.