The current EAU-EANM-ESTRO-ESUR-ISUP-SIOG Guidelines recommend radiolabeled prostate-specific membrane antigen (PSMA), choline, or fluciclovine PET/CT at biochemical recurrence (BCR) of prostate cancer (PCa) after radical prostatectomy. While studies compared [68Ga]Ga-PSMA-11 and [18F]Fluciclovine, data on 18F-labelled PSMA-ligands versus [18F]Fluciclovine in patients with low prostate-specific antigen (PSA) levels (< 2 ng/mL) are limited. This study compared the detection rates of [18F]Fluciclovine and [18F]DCFPyL PET/CT in patients with BCR after robot-assisted radical prostatectomy (RARP). Secondary objectives included stratifying detection rates by PSA level, anatomical regions and assessing inter-observer agreement. In this prospective, single-center study, patients with BCR (PSA 0.2-2.0 ng/mL) underwent both [18F]Fluciclovine and [18F]DCFPyL PET/CT within 15 days. Three blinded nuclear medicine experts independently reviewed all scans. Lesions were classified as positive or negative in predefined regions (i.e., prostate bed, pelvic and extra-pelvic lymph nodes, bone, and visceral). Discrepancies were resolved by consensus, defined as majority agreement (≥ 2/3 readers). Inter-observer agreement was assessed using Fleiss’ kappa. Overall scan positivity was 44

BACKGROUND:Prostate-specific membrane antigen (PSMA)-radioguided surgery (RGS) is an emerging technique providing real-time intraoperative guidance. The prospective TRACE-I trial demonstrated that robot-assisted 99mtechnetium-PSMA-Investigation & Surgery-RGS ([99mTc]Tc-PSMA-I&S-RGS) using a DROP-IN gamma probe is feasible and safe in recurrent prostate cancer (PCa). OBJECTIVE:To report the oncological outcmes of a post hoc analysis of the prospective TRACE-I trial cohort. DESIGN, SETTING, AND PARTICIPANTS:TRACE-I prospectively enrolled 30 patients with biochemical recurrence (prostate-specific antigen (PSA) ≥0.2 ng/ml after radical prostatectomy (RP) or ≥2 ng/ml above nadir after radiotherapy (RT) and ≤3 pelvic recurrences (nodal and/or local) on PSMA-positron emission tomography/computed tomography (PET/CT; 2020-2023). INTERVENTION:Patients underwent single-photon emission CT/CT and then robot-assisted PSMA-RGS. OUTCOMES MEASUREMENTS AND STATISTICAL ANALYSIS:Oncological outcomes were biochemical progression (PSA ≥0.2 ng/ml after RP or ≥2 ng/ml above nadir after RT), radiological recurrence on PSMA-PET/CT, and time to salvage therapy. Biochemical progression-free survival (bPFS), distant metastasis-free survival (dMFS), and therapy-free survival (TFS) were analysed using Kaplan-Meier and univariable Cox regression. RESULTS AND LIMITATIONS:Among 30 patients (19 RP, 9 RT, and 2 RP + RT), the median age was 68 yr, and the median PSA at RGS was 1.02 ng/ml (interquartile range, 0.46-2.86), 28 (93%) showed PSA decline after RGS, and 20 (66%) reached PSA <0.2 ng/ml or PSA nadir. The 1- and 2-yr bPFS were 40% and 30%; 2-yr dMFS and TFS were 62% and 58%, respectively. Recurrences were pelvic in 37% and distant in 40%. Limitations include single-centre design and small sample size. CONCLUSIONS:PSMA-RGS in the robotic setting for recurrent PCa shows an early PSA decline in almost all patients. Although biochemical progression after PSMA-RGS is common, PSMA-RGS presents an opportunity to prolong bPFS and TFS in a selection of patients. PATIENT SUMMARY:We updated outcomes from TRACE-I patients with recurrent prostate cancer. We found that PSMA-guided surgery led to PSA declines in most patients and delayed disease progression in some, but careful patient selection is essential.

Image-guided surgical navigation can enhance surgical precision and safety. The rise of robot-assisted surgeries has increased the need of incorporating navigation systems. Our goal is to evaluate the integration of three novel techniques on registration, instrument tracking and visualization with navigation using the robot-assisted sentinel lymph node biopsy (SLNB). A prospective feasibility study was performed at the Netherlands Cancer Institute (November 2023–July 2025). In total, 30 patients scheduled for SLNB participated. First, registration and localization accuracy were analyzed. Secondly, surgeons answered questionnaires to evaluate the ultrasound registration, instrument tracking and enhanced visualization. Virtual reality (VR) and augmented reality (AR) were compared in the last ten patients. Feasibility was determined with the sentinel nodes (SN) percentage that were successfully localized by navigation and validated ex vivo with the gamma probe. Per-protocol, the first ten patients were used for workflow optimization; the subsequent 20 patients were included in the analysis. Ultrasound registration was fast (7 min), accurate (0.1 cm) and intuitive. Tracked instruments were well-integrated and helped to localize precisely the SN (0.3 cm). Surgeons preferred VR while opening the resection path to find the SN and AR in proximity for exact localization. Using navigation, successful identification was achieved in 90

BACKGROUND:The clinical significance of internal mammary chain sentinel lymph nodes (IMCSNs) remains debated, with no consensus on the diagnostic and prognostic value of IMCSN removal. A supporting argument for IMCSN removal is its aid in adjuvant therapy decisions, whereas opposing arguments are that IMCSN removal rarely alters management and may increase complication risk. METHODS:Patients with cN0 breast cancer with internal mammary chain (IMC) drainage on preoperative lymphoscintigraphy between 2012 and 2023 were included. The primary outcome was the clinical impact of IMCSN removal on adjuvant treatment strategy. Secondary outcomes were recurrence-free survival and overall survival, comparing patients with and without IMCSN removal. RESULTS:In total, 688 patients with cN0 breast cancer were included. In 141 (20.5%) patients, IMCSN removal was performed, resulting in 11 tumor-positive biopsies (7.8%). In 14 patients (9.9%), IMCSN removal alone led to changes in the adjuvant treatment strategy; 10 patients (6.9%) received IMC irradiation solely because of a tumor-positive IMCSN biopsy, three patients (2.1%) were spared IMC irradiation following a tumor-negative IMCSN biopsy, and one patient (0.7%) received systemic treatment based on a tumor-positive IMCSN biopsy. After a median follow-up of 65.3 months, no significant difference in recurrence-free survival (p = 0.566) or overall survival (p = 0.441) was observed between the IMCSN removal and non-removal groups. DISCUSSION:IMCSN removal has limited clinical impact on adjuvant treatment decisions and does not improve recurrence and survival outcomes. Therefore, we recommend that IMCSN removal not be performed in patients with cN0 breast cancer with IMC drainage on preoperative lymphoscintigraphy.

Prostate-specific membrane antigen (PSMA) PET/CT is recognized as the most accurate imaging modality for staging of patients with intermediate and high-risk prostate cancer (PCa). PSMA PET/CT has also shown potential in the local (T) staging of primary PCa. The purpose of this study was to explore the value of quantitative PSMA PET/CT parameters in addition to the standard visual assessment for local T-stage classification in a large single-center retrospective cohort. Sequential intermediate- and high-risk primary PCa patients who underwent staging PSMA PET/CT prior to robot-assisted radical prostatectomy were included. Visual assessment of T-stage (miT-stage) was performed alongside quantitative analysis of PSMA PET/CT parameters, including SUVmax, SUVpeak, tumor volume (PSMA-vol), total lesion PSMA expression (PSMA-TL), and tumor longest capsule contact (LCC). The pathological tumor stage derived from radical prostatectomy specimens served as the reference standard. Univariable and multivariable logistic regression analyses were performed to develop clinical risk models for predicting pT3-stage disease. A total of 223 evaluable patients with PSMA-positive primary PCa were included. Univariable analyses of individual imaging parameters yielded AUCs of 0.53–0.63 for pT3a, 0.64–0.74 for ≥ pT3b, and 0.59–0.69 for overall ≥ pT3-stage. In multivariable analyses, LCC was the sole independent predictor for pT3a stage; miT-stage, LCC, and PSMA-vol were independent predictors for ≥ pT3b-stage; and LCC together with PSMA-vol were independent predictors for overall ≥ pT3-stage. Clinical risk models incorporating these predictors achieved AUCs of 0.62 for pT3a, 0.79 for ≥ pT3b, and 0.70 for ≥ pT3-stage. Quantitative parameters derived from PSMA PET/CT scans provide additional diagnostic accuracy for detecting extraprostatic tumor extension, particularly for ≥ pT3b-stage disease, outperforming visual assessment (miT-stage) alone.

Background and objective: Prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) is increasingly used for primary staging in prostate cancer. Owing to accurate detection of small metastases on PSMA-PET/CT, patient selection for robot-assisted radical prostatectomy (RARP) has likely changed. This study analyzes oncological outcomes in patients undergoing RARP and extended pelvic lymph node dissection (ePLND) after PSMA-PET/CT staging, compared with those without PSMA-PET/CT. Methods: Patients who underwent staging with PSMA-PET/CT before RARP and ePLND ("PSMA cohort"; 2016-2021) were compared with patients staged without PSMA-PET/ CT ("historical cohort"; 2013-2016). Propensity score matching using preoperative variables was performed to limit confounding. As primary outcome measure of biochemical recurrence (BCR)-free survival (BFS) was analyzed, with BCR defined as a prostate specific antigen value of >= 0.2 ng/ml or start of additional therapy after surgery. Key findings and limitations: After matching, 880 patients were included (440 in each cohort). The median follow-up was 35 mo (interquartile range 21-60) for the entire cohort. In the PSMA cohort, 126/440 patients (29%) experienced BCR versus 205/440 (47%) in the historical cohort (log-rank test p = 0.032). A multivariable Cox regression analysis showed an independent effect of preoperative PSMA-PET/CT staging on BFS (hazard ratio 0.70, 95% confidence interval 0.55-0.89, p = 0.0030). Conclusions and clinical implications: Patients who underwent staging with PSMA-PET/ CT had longer biochemical progression-free survival after RARP and ePLND than those without PSMA-PET/CT. This suggests that PSMA-PET/CT staging alters patient selection for RARP and ePLND, and is associated with improved early oncological outcomes for patients who still undergo surgery. Patient summary: Prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) at the diagnosis of prostate cancer leads to better visualization of metastases and therefore better selection of prostate cancer patients for surgery. Patients who underwent a PSMA-PET/CT scan at the time of diagnosis showed improved oncological outcomes, including longer progression-free survival and less prostate-specific antigen persistence after surgery. (c) 2024 Published by Elsevier B.V. on behalf of European Association of Urology.

Salvage neck dissection (ND) is the treatment of choice for residual neck disease after (chemo)radiotherapy for head-and-neck squamous cell carcinoma (HNSCC). Although ND is a relatively safe surgical procedure, several studies have shown that salvage ND will increase the morbidity of (chemo)radiotherapy with possible increase in acute and late toxicity and deterioration of quality-of-life. Therefore, unnecessary salvage ND need to be avoided. However, the available literature could not identify potential groups at higher risk of post-operative complications because of the missing demographic information and the heterogeneity in studies and outcome data. We aim to report on the types, rates, and severity of postoperative complications and to identify groups of patients at high risk of these complications. Of 908 patients with node-positive HNSCC primarily treated with (chemo)radiotherapy between 2008 and 2022, 130 (14

PURPOSE:The majority of patients with HNSCC primarily treated with (chemo)radiation receive bilateral elective nodal irradiation(B-ENI). However, this concept has shown to result in a considerable toxicity and deterioration of quality-of-life. We report on the technical feasibility of a SPECT/CT-based sentinel node procedure (SNP) approach to select patients for unilateral ENI (U-ENI). PATIENTS AND METHODS:The primary tumor of 90 patients with lateralized T1-4N0-3 (N2c excluded) carcinoma of oropharynx, larynx and hypopharynx were injected under local anesthesia with indocyanine green (ICG)-99mTechnetium(Tc)-nanocolloid, 3-4 h later SPECT/CT was done for lymph drainage mapping (LDM). Patients without contralateral drainage (CLD) received U-ENI and those with CLD received SNP. Patients with negative SN still received U-ENI while those with positive SN received B-ENI. ENDPOINTS:contralateral regional failure and toxicity. RESULTS:Of the entire group, 82% had oropharyngeal cancer, 83% T1-2, and 77% Node-positive disease. LDM was successful in all patients. Flexible laryngoscope with working channel was used for the peri-tumoral injection in 53% of patients. Only 6 patients experienced the procedure as uncomfortable/painful. CLD was seen in 41 patients (45.5%), mainly in level II (63.4%). All of them received SNP and only 8 patients had positive SLN (19.5%), 7 of which in level II. These patients received B-ENI and the other 82 patients (91%) U-ENI. There was only one minor surgical complication (postoperative bleeding). CONCLUSIONS:The SPECT/CT-based SNP to guide U-ENI is feasible, safe and has resulted in significant increase in proportion of patients treated by U-ENI. The results of oncologic outcome and toxicity need to be awaited.

183 Background: Radium-223 is a therapeutic option for metastatic castration-resistant prostate cancer (mCRPC) patients with symptomatic bone metastases and consists of up to 6 monthly injections. After the approved 6 radium-223 injections, treatment may be repeated. This study evaluated the safety and efficacy of radium-223 re-treatment in mCRPC patients in routine clinical practice. Methods: This multicenter, retrospective cohort study included patients with bone mCRPC who previously received 6 consecutive injections of radium-223 according to standard of care, and received at least one radium-223 re-treatment injection between 2014 and 2024. Patients with visceral metastases were excluded. Primary endpoint was safety (hematological and non-hematological adverse events (AEs), including skeletal-related events (SREs)). Secondary endpoints were the number of administered injections, overall survival, and alkaline phosphatase (ALP) and prostate-specific antigen (PSA) responses. Exploratory analyses intended to find variables associated with ALP response during re-treatment and completion of radium-223 re-treatment. Results: Across 7 Dutch medical centers, 61 patients were included. Median age was 75 years, 44% received prior chemotherapy, 87% previously received at least one androgen receptor pathway inhibitor and 51% received concomitant bone health agents. Median number of prior systemic therapies was 3. 81% of patients had an ECOG performance status ≥1. 95% of patients had at least one hematological AE, including 14% grade 3 hematological AEs. In total, 44 (75%) patients experienced at least one non-hematological AE during radium-223 re-treatment. No grade 4-5 AEs occurred. 11 (18%) patients developed a SRE during radium-223 re-treatment, including 2 (3%) patients with spinal cord compression. Time until first SRE was 9.5 months (95% CI, 6.2-12.8). The patients received a median number of 6 radium-223 re-treatment injections (IQR; 4-6). Overall survival was 16.9 months (95% CI, 11.9-21.9) from start of re-treatment. 56% of patients had a ≥30% ALP response and 25% had a ≥30% PSA response. Other than elevated ALP levels at baseline, no variables were associated with ≥30% ALP response during radium-223 re-treatment. High baseline hemoglobin levels, no prior chemotherapy and a PSA response ≥30% during the initial radium-223 therapy were predictors for completion of 6 radium-223 re-treatment injections. Conclusions: Radium-223 re-treatment was well tolerated and is therefore deemed safe in selected mCRPC patients. In addition, the high number of administered injections and the high ALP response rates suggest benefit in this cohort of advanced mCRPC patients. Further research should directly compare radium-223 re-treatment and other life-prolonging therapies to determine the position of radium-223 re-treatment within the therapeutic landscape of mCRPC.

Background/Objectives: In men with biochemical recurrence (BCR) after a radical prostatectomy (RP), salvage radiotherapy (SRT) is commonly recommended when imaging shows no metastases. The optimal management for patients with negative prostate-specific membrane antigen (PSMA) PET/CT findings at BCR remains uncertain. This study evaluated outcomes of patients with BCR and negative PSMA PET/CT to identify who may be safely observed and who may benefit from early SRT. Methods: This retrospective multicentre cohort study included 89 patients with BCR and negative PSMA PET/CT findings after a RP (2015–2022) who were managed with observation. The exclusion criteria were PSA levels ≥ 0.8 ng/mL at baseline, prior SRT, or prior or ongoing hormonal therapy. Minimum follow-up was 3 years. Biochemical progression (PSA rise > 0.2 ng/mL above baseline or initiation of additional treatment) and radiological progression (local or metastatic disease on follow-up PSMA PET/CT) were assessed. Patients were stratified by EAU BCR-risk classification. Multivariable Cox regression included age, biochemical persistence (BCP) after a RP, pathological tumour stage (pT), pathological ISUP grade group (pISUP), node status (pN), margin status (R), and PSA doubling time (PSAdt). Results: The median age was 66 years (IQR 60–69) and the median PSA measurement at BCR was 0.2 ng/mL (IQR 0.2–0.3). A total of 27/89 (30%) patients were EAU BCR low-risk and 62/89 (70%) were high-risk. At three years, biochemical progression occurred in 14/27 (52%) low-risk vs. 51/62 (83%) high-risk patients, with time to progression being 21 vs. 12 months (p = 0.01). A pISUP grade group ≥ 4 (HR 2.04 [95%-CI 1.11–3.74]; p = 0.022) and a PSAdt < 20 months (HR 5.72 [95%-CI 2.41–13,56]; p < 0.01) independently predicted biochemical progression. Radiological progression occurred in 43/68 (66%) rescanned patients, with 32/43 (74%) showing disease outside the prostatic fossa. Conclusions: Nearly half of patients with BCR and negative PSMA PET/CT findings who were classified as EAU BCR low-risk remained progression-free at three years. These results support a risk-adapted approach, indicating that SRT may be deferred in selected low-risk patients.

Background and objective Image-guided surgical navigation (IGSN) can enhance surgical precision and safety. The expansion of minimally invasive surgery has increased the demand for integration of these navigation systems into robot-assisted surgery. Our objective was to evaluate the integration of electromagnetic tracking with IGSN in robot-assisted sentinel lymph node biopsy (SLNB). Methods We conducted a prospective feasibility study to test the use of IGSN in SLNB. In total, 25 patients scheduled for SLNB at The Netherlands Cancer Institute were included (March 2022 to March 2023). SLNB using IGSN was performed using a standardised technique with a da Vinci robot (Intuitive Surgical, Sunnyvale, CA, USA) in four-arm configuration. Feasibility was determined as the percentage of sentinel nodes (SNs) successfully identified via IGSN. Successful SN resection was defined as SNs correctly localised via navigation and validated ex vivo with a gamma probe. Surgeon feedback on the robot-assisted IGSN workflow was evaluated using the System Usability Scale (SUS). Key findings and limitations In accordance with the protocol, the first five patients were used for workflow optimisation, and the subsequent 20 patients were included in the analysis. IGSN led to successful identification of 91% (50/55) of the SNs. There were no complications associated with navigation. The surgeon feedback (SUS) was 60.9, with lowest scores reported for the user interface and workflow integration. Conclusions IGSN during robot-assisted surgery was feasible and safe. The technique allowed identification and removal of predefined small pelvic lymph nodes. Patient summary We carried out a study on the feasibility of imaging-guided navigation in robot-assisted prostate surgery. Our results show that this technique is feasible, safe, and effective.

Background and objective: Prostate-specific membrane antigen positron emission tomography/computed tomography (PSMA-PET/CT) and new treatment modalities have expanded the possibilities for diagnosing and managing metastatic prostate cancer, but have also raised questions about their implementation in daily clinical practice. We sought consensus on definitions, preferred imaging modality for staging, and treatment selection in the era of next-generation imaging. Methods: A modified Delphi method involved two voting rounds and a face-to-face multidisciplinary meeting with 40 Dutch prostate cancer (PCa) experts. Consensus was reached if ≥75% of the panellists chose the same option. Appropriateness was assessed by the RAND Corporation/University of California Los Angeles appropriateness method. Key findings and limitations: There was consensus on performing metastatic screening with PSMA-PET/CT for unfavourable intermediate- or high-risk PCa. PSMA-PET/CT findings were considered feasible for determining treatment in synchronous metastatic hormone-sensitive prostate cancer, but there was no agreement on the validity of the CHAARTED criteria for interpreting the PSMA-PET/CT findings. If the PSMA-PET/CT findings led to upstaging after conventional imaging, 76% of panellists would opt for treatment intensification. In case of downstaging, 71% would choose for deintensification. Panellists would generally treat patients based on metastatic disease volume as per the CHAARTED criteria, except for bulky low-volume disease (LVD) and LVD with multiple (more than ten) bone metastases, all within the axial skeleton. This would be classified as LVD but treated as high-volume disease. Limitations are that the statements are largely consensus based and originate from a national (Dutch) perspective. Conclusions and clinical implications: PSMA-PET/CT was considered the preferred modality for initial PCa staging, which is nowadays the standard of care in The Netherlands. The majority of panellists would incorporate PSMA-PET/CT findings for treatment planning, including intensification and deintensification, but the criteria for interpreting metastatic disease volume on PSMA-PET/CT are still uncertain. Patient summary: A group of Dutch medical specialists discussed on how to diagnose metastatic hormone-sensitive prostate cancer and choose the most appropriate treatment for patients with this condition. It was concluded that imaging based on Prostate-specific membrane antigen (PSMA) positron emission tomography (PET) helps determine appropriate treatment options, with most experts supporting treatment adjustments based on PSMA-PET/computed tomography (CT) results. However, there is still some uncertainty about the criteria for interpreting the extent of metastatic disease with PSMA-PET/CT.

OBJECTIVE:To investigate whether combination treatment of prostate-specific membrane antigen (PSMA)-based radioguided surgery (RGS) with short-term androgen deprivation therapy (ADT) improves oncological outcomes in men with oligorecurrent prostate cancer (PCa) as compared to treatment with short-term ADT only. METHODS:The TRACE-II study is an investigator-initiated, prospective, randomised controlled clinical trial. Patients (aged >18 years) with hormone-sensitive recurrent PCa after radical prostatectomy or radiotherapy (brachytherapy or external beam radiotherapy), with involvement of ≤2 lymph nodes or local oligorecurrent disease within the pelvis as determined by PSMA positron emission tomography (PET)/computed tomography (CT) are randomly assigned in a 1:1 ratio between 6-month ADT (Arm A) or 6-month ADT plus RGS (Arm B). The primary objective is to determine clinical progression-free survival (CPFS) at 24 months. After PSMA-RGS, CPFS is defined as the time between the start of treatment and the appearance of a re-recurrence (any N1 or M1) as suggested by PSMA-PET/CT or symptoms related to progressive PCa, or death from any cause. The secondary objectives include metastasis-free survival at 2, 5 and 10 years, biochemical progression-free survival at 2 years, and patient-reported quality of life at 2, 5 and 10 years. A total of 60 patients, 30 per arm, will be included. The trial is powered (80%) to detect at least a 30% absolute difference in CPFS between the two study arms in the period 2 years after randomisation. We expect to enrol the required participants in 3 years. The study has an expected duration of 5 years in total. CONCLUSIONS:Combining RGS with short-term ADT might be oncologically beneficial for patients with oligorecurrent PCa. In this first randomised controlled trial, we are investigating the potential oncological benefits of this combined treatment, while also focusing on maintaining quality of life.

Prostate-specific membrane antigen (PSMA) PET is used to select patients with recurrent prostate cancer for metastasis-directed therapy. A surgical approach can be achieved through radioguided surgery (RGS), using a Drop-In gamma-probe that traces lesions that accumulate the radioactive signal. With the aim of guiding patient selection for salvage surgery, we studied the correlation between the SUVmax of lesions on preoperative PSMA PET/CT and their intraoperative counts/s measured using the Drop-In gamma-probe. Methods: A secondary analysis based on the prospective, single-arm, and single-center feasibility study was conducted (NCT03857113). Patients (n = 29) with biochemical recurrence after previous curative-intent therapy and a maximum of 3 suggestive lesions within the pelvis on preoperative PSMA PET/CT were included. Patients treated with androgen deprivation therapy within 6 mo before surgery were excluded. All patients received an intravenous injection of Tc-99m-PSMA-I&S 1 d before surgery. Radioguidance was achieved using a Drop-In gamma-probe. Correlation was determined using the Spearman rank correlation coefficient (rho s). Subgroup analysis was based on the median SUVmax Results: In total, 33 lesions were visible on the PSMA PET/CT images, with a median overall SUVmax of 6.2 (interquartile range [IQR], 4.2-9.7). RGS facilitated removal of 31 lesions. The median Drop-In counts/s were 134 (IQR, 81-220) in vivo and 109 (IQR, 72-219) ex vivo. The intensity of the values correlated with SUVmax (rho s = 0.728 and 0.763, respectively; P < 0.001). Subgroup analysis based on median SUVmax in the group with an SUVmax of less than 6 showed no statistically significant correlation with the numeric signal in vivo (rho s = 0.382; P = 0.221) or the signal-to-background-ratio (rho s = 0.245; P = 0.442), whereas the group with an SUVmax of 6 or more showed respective statistically significant positive correlations (rho s = 0.774 [P < 0.001] and rho s = 0.647 [P = 0.007]). Conclusion: Our findings indicate that there is a direct relation between SUVmax on PSMA PET/CT and the readout recorded by the surgical Drop-In probe, thereby indicating that SUVmax can be used to select patients for PSMA RGS. For more definitive subgroup definitions for treatment recommendations, further studies are necessary to validate the present findings.

Objectives: To explore the factors affecting the lymph node metastasis (LNM) detection performance of prostate-specific membrane antigen positron emission tomography/computed tomography (PSMA PET/CT) and to evaluate its prognostic value for biochemical recurrence after radical prostatectomy (RP). Methods: Patients who had intermediate- or high-risk prostate cancer and underwent robot-assisted (RA)RP between 2017 and 2021 were included. Initial lymph node staging was carried out using PSMA PET/CT. Sensitivity, specificity, and positive (PPV) and negative (NPV) predictive values were calculated. A cut-off value for LNM tumor deposit size that maximizes specificity was investigated and a post hoc specificity analysis was carried out. In survival analysis for biochemical progression-free survival (bPFS) after RP, Kaplan-Meier curves of molecular imaging (mi)N0 and miN1 patients were compared using the log-rank test and separate Cox regression models were developed to reveal the significance of PSMA PET/CT staging in pre- and post-surgery settings. Results: In 583 patients with a prevalence of pathology-proven LNM of 27.4%, overall sensitivity, specificity, PPV, and NPV of PSMA PET/CT per patient were 26.3% [95%CI 18.9-35.5], 93.9% [95%CI 84.9-100], 61.8% [95%CI 44.5-83.5], and 77.1% [95%CI 69.7-85.1], respectively. PSMA PET/CT showed a better sensitivity as LNM tumor deposit size increased (p = 0.003 OR 2.4 [95%CI 1.3-4.4]) and a better specificity in pT3-4 tumors (96.1%) versus pT2 (91.1%, p = 0.024 OR 2.7 [95%CI 1.1-6.3]). After adjustment according to 5.5 mm LNM tumor deposit size, which showed the best discriminative performance (AUC: 0.905 [95%CI 0.804-1.000, p < 0.001]), overall sensitivity tripled (90.2%, p < 0.001). The 1-year bPFS was 56.0% and 83.3% for miN1 and miN0 patients, respectively (p < 0.001). Whereas miN0pN1 was not, miN1pN1 disease was independently associated with decreased bPFS (HR:2.1 95%CI 1.3-3.4, p < 0.001). Conclusions: PSMA PET/CT has a lymph node tumor burden-dependent and cohort-driven diagnostic ability but consequently a strong independent prognostic value for predicting biochemical recurrence after RARP.

Purpose of the Report Localization techniques are needed to facilitate resection of nonpalpable lesions. In this study, the feasibility of radio-guided occult lesion localization (ROLL) with 99m Tc is investigated for the localization of nonpalpable, small, suspicious, or proven melanoma or soft tissue sarcoma lesions at various locations throughout the body. Patients and Methods Patients with nonpalpable, suspicious, or proven melanoma or soft tissue sarcoma lesions were selected for this study. Within 24 hours before surgery, a median dose of 33.92 MBq 99m Tc-labeled human albumin particles ( 99m Tc-NA or 99m Tc-MAA) was injected in the lesion under ultrasound guidance. A hand-held gamma probe was used to detect the radioactive signal and guidance during surgery. Results In this study, 20 patients with a total of 25 lesions were included and analyzed. The median size of the lesions was 1.8 cm (interquartile range [IQR], 1.8–4.0 cm), of which 44% were intramuscular located and 36% were subcutaneous, and 20% consisted of suspicious lymph nodes, mostly in the lower extremity. At median 4 hours (IQR, 3–6 hours) postinjection, 99m Tc ROLL showed a 100% intraoperative identification rate with proper signal identification with the gamma probe in all patients. With a median surgery time of 76 minutes (IQR, 45–157 minutes), all targeted lesions could be resected without 99m Tc-related complications, resulting in 88% microscopically margin-negative resection. No reoperations were needed for the same lesion. Conclusions The 99m Tc ROLL procedure is feasible for the localization and excision of small, nonpalpable melanoma and soft tissue sarcoma lesions at various locations in the body.