Faculty Bibliography

OBJECTIVE:Indeterminate lesions on prostate-specific membrane antigen (PSMA)-PET are challenging to address. We aimed to develop, implement, and evaluate a multidisciplinary consensus algorithm that integrates existing interpretation systems with multimodality imaging and clinicopathological information for interpreting indeterminate bone and lymph node lesions on PSMA-PET. MATERIALS AND METHODS/METHODS:This was a retrospective single-center study on a prospectively implemented algorithm. We included all consecutive prostate cancer patients whose PSMA-PET findings for indeterminate bone lesions or lymph nodes were discussed at a multidisciplinary tumor board (MDT) in 2024-2025. An algorithm determining the level of suspicion for metastasis was developed in a multidisciplinary fashion, incorporating lesion location, conventional imaging features, PSMA-PET characteristics, and clinicopathological information. The application of the algorithm and outcomes were documented, compared against a composite reference standard. Comparisons were made with PSMA-RADS and PROMISE V2 PSMA-expression scores. RESULTS:81 patients (median age 68, interquartile range 64-75) were included. Algorithm results were benign (48.1% [39/81]), equivocal (4.9% [4/81]), metastasis (40.7% [33/81]), and mixed (benign and metastatic lesions, 6.2% [5/81]). The algorithm was correct in 94.1% (64 of 68 patients with a sufficient reference standard). The algorithm was discordant with PSMA-RADS in 54.3% (44/81) and with PROMISE V2 PSMA-expression score in 71.6% (58/81). The frequency of equivocal lesions was lower using the algorithm (4.9% [4/81]) compared with PSMA-RADS (53.1% [43/81]) and PSMA-expression score (64.2% [52/81]). CONCLUSION/CONCLUSIONS:A multidisciplinary consensus algorithm for interpreting indeterminate bone lesions and lymph nodes on PSMA-PET was developed and implemented. Integrating clinicopathological information and multimodality imaging in an MDT setting reduced equivocal interpretations. KEY POINTS/CONCLUSIONS:Question While prostate-specific membrane antigen (PSMA)-PET has become essential in the management of prostate cancer, indeterminate bone lesions and lymph nodes remain challenging to address. Findings A multidisciplinary algorithm for interpreting indeterminate bone lesions and lymph nodes on PSMA-PET, incorporating clinicopathological information and multimodality imaging, reduced the frequency of equivocal interpretations. Clinical relevance An algorithm for interpreting indeterminate bone lesions and lymph nodes on PSMA-PET, incorporating clinicopathological information and multimodality imaging in a multidisciplinary tumor board setting, decreases the frequency of equivocal interpretations and can potentially help management decisions.

Post-radiotherapy erectile dysfunction (ED) can significantly impact the quality of life of patients with prostate cancer (PCa). Critical anatomical structures, such as the neurovascular bundle (NVB), internal pudendal arteries (IPA), penile bulb, and corporal tissues track in close proximity to the prostate, making them susceptible to radiation-related damage. This study aimed to evaluate the anatomical patterns of these structures and their relationship with the prostate, and to provide comprehensive illustrative examples on MRI. Consecutive patients with PCa who underwent MRI-linear accelerator (LINAC)-based stereotactic body radiotherapy (SBRT) in January-December 2024 were included. NVB patterns were classified into 3 categories: (1) "classical" with discrete NVB elements, (2) "adherent", dispersed and adherent to prostatic capsule, and (3) "absent". The smallest distance between the IPA and the prostate capsule and membranous urethral length (MUL), serving as a surrogate for distance between corporal tissue and prostatic apex, were also measured. These MRI findings were compared between prostate volumes >40 and <40 ml and between MRI/pathological features of the dominant intraprostatic lesion. A total of 160 men (median age 70 years, interquartile range [IQR] 64-76) were included. The most common NVB pattern was "classic" (80.0-85.0%), followed by the "adherent" NVB pattern (13.8-18.1%). The median smallest distance between the IPA and prostate was 2.3 cm (IQR 1.8-2.8 cm), with 3.1-3.8% less than 1.0 cm. The median MUL was 1.5 cm (IQR, 1.2-1.8 cm), with 2.5% of patients less than 1.0 cm. No significant association was found between these MRI features and prostate volume or other variables (p = 0.09-0.99). In conclusion, most PCa patients demonstrated favorable anatomy for potential dose sparing of critical structures. Comprehensive MRI illustrations are provided to help radiation oncologists recognize the location, trajectory, and relationship of these structures, facilitating their contouring and ultimately aiding in achieving meaningful dose reductions to these erectile function structures.

OBJECTIVE:To develop a tool for the clinical hybrid imaging workflow which combines morphologic and functional measurements. And to quantify the number of clicks saved per positron emission tomography/computed tomography (PET/CT) interpretation. METHODS:A tool was developed where a volume of interest (VOI) is automatically created around line distance measurements. VOI statistics for both PET and CT component, and line distances are generated and displayed. Usage data for the first two months after introduction of the tool was analyzed. RESULTS:Eleven radiologists and nuclear medicine physicians used the tool in 364 PET/CTs. In 19% of examinations, the novel tool was the only tool that needed to be used. The novel combined tool was used 1001 times, whereas the traditional spherical VOI had been placed 1131 times. The usage ratio of new to traditional tool differed significantly between examinations with ≤ 6 annotations (ratio 1.0) versus > 6 annotations (ratio 0.63, p = 0.030). The average number of saved clicks per PET/CT was estimated at 16.5. CONCLUSION/CONCLUSIONS:A novel combined measurement tool for hybrid imaging was implemented and saved on average 16.5 clicks per examination. These improvements contribute to a smoother workflow and demonstrate the positive impact of thoughtful software design in medical practice.

Prostate-specific membrane antigen (PSMA) PET is a powerful tool for prostate cancer staging and restaging, providing higher sensitivity and specificity than conventional imaging. The recognition of interpretive pitfalls led to the development of various scoring systems and frameworks, which in turn created challenges for consistent interpretation. The Prostate Cancer Molecular Imaging Standardized Evaluation (PROMISE) version 2 classification integrates the five-point PRIMARY score for assessing local disease, the molecular imaging TNM stage for disease extent, and the PSMA expression score to assess eligibility for PSMA-targeted radioligand therapy. The PSMA Reporting and Data System (PSMA-RADS) classifies PSMA PET/CT findings on the basis of the likelihood of presence of prostate cancer. For assessing therapy response, PSMA PET Progression (PPP) criteria focus on new lesions and clinical or biochemical progression, whereas Response Evaluation Criteria in PSMA PET/CT (RECIP 1.0) assess new lesions and changes in total PSMA-positive total tumor volume. The European Association of Nuclear Medicine (EANM) E-PSMA guideline and EANM-Society of Nuclear Medicine and Molecular Imaging procedure guidelines provide standardized reporting recommendations, incorporating elements from existing systems such as PROMISE, PSMA-RADS, and PPP. Nevertheless, such systems can be essential for optimizing prostate cancer management and facilitating communication among imaging professionals, clinicians, and patients. This article outlines these systems and discusses potential strengths and weaknesses.

Various imaging modalities play key roles throughout the different stages of prostate cancer. Each imaging modality has different strengths and weaknesses and various scoring systems or frameworks are used to interpret their findings. Discordances between imaging modalities or interpretation frameworks, and even with clinicopathological findings are not uncommon. Discordances often lead to challenges in the decision-making process, especially with dynamically changing indications for newer imaging modalities. While more research is needed on harmonizing interpretations across different modalities, multidisciplinary team discussion is key to optimizing management of patients with prostate cancer when such discordances are present. In this comprehensive review, we take a deep dive in to these various discordances seen in clinical practice and explore their clinical implications.

PURPOSE/OBJECTIVE:To explore pragmatic approaches integrating MRI and PSMA-PET/CT for evaluating extraprostatic extension (EPE) of prostate cancer (PCa). METHODS:>12). Diagnostic performance was tested with receiver operating characteristic (ROC) curves and compared using DeLong and McNemar tests. RESULTS:>12 among which 87.5% (7/8) were corrected upgraded and had pathological EPE. CONCLUSION/CONCLUSIONS:Several pragmatic approaches were explored for integrating MRI and PSMA-PET/CT to assess EPE in PCa. Combining morphological information from MRI and PSMA expression on PET/CT demonstrated good diagnostic performance and may be a simple pragmatic integrated method that can be used.

PURPOSE/UNASSIGNED:Stomal complications after ileal conduit urinary diversion are challenging and can negatively affect quality of life after radical cystectomy. Parastomal hernias (PHs) develop in up to half of patients; 30% to 75% are symptomatic, and up to one-third require surgical repair. Recurrence rates after local tissue repair are high, and relocation of the stoma requires closure of the original defect, placing both sites at risk for hernias. MATERIALS AND METHODS/UNASSIGNED:The primary aim of this randomized phase 3 trial was to test whether prophylactic placement of a parastomal mesh at ileal conduit formation reduced radiographic PH (rPH) rate compared with standard techniques without mesh; final rPH assessment was at 24 months. Ultrapro semiabsorbable mesh was placed in a sublay position dorsal to rectus muscle and anterior to posterior rectus sheath. RESULTS/UNASSIGNED:= .2). CONCLUSIONS/UNASSIGNED:We were unable to identify a clinical benefit to prophylactic parastomal mesh placement. Based on these findings, mesh at the time of conduit creation should not be used to avoid PH formation.

BACKGROUND AND OBJECTIVE/OBJECTIVE:Staging of bladder cancer (BC) remains a cornerstone of treatment planning, especially in distinguishing non-muscle-invasive BC (NMIBC) from muscle-invasive BC (MIBC). Multiparametric magnetic resonance imaging (mpMRI), together with the Vesical Imaging-Reporting and Data System (VI-RADS) and its neoadjuvant chemotherapy version (nacVI-RADS), has emerged as a noninvasive, standardised tool for local staging and response assessment. Our aim was to provide urologists with a practical, up-to-date overview of bladder mpMRI and its application in diverse clinical settings. METHODS:We conducted a narrative review of the literature, including original studies, meta-analyses, international guidelines, and expert consensus documents, on the role of magnetic resonance imaging (MRI) in the BC diagnostic and therapeutic pathway. KEY FINDINGS AND LIMITATIONS: mpMRI with VI-RADS improves the accuracy of preoperative staging, helps in avoiding repeat transurethral resection of bladder tumour in selected NMIBC cases, and supports decision-making in MIBC in MRI-based pathways. nacVI-RADS allows assessment of treatment responses after systemic therapies, and can potentially guide bladder-sparing approaches. Barriers include variability in access, guideline inconsistency, the reproducibility of interpretation, and limited cost-effectiveness data. However, ongoing multicentre validation efforts and standardised reporting are helping to mitigate these issues. CONCLUSIONS AND CLINICAL IMPLICATIONS/CONCLUSIONS:mpMRI, VI-RADS, and nacVI-RADS represent essential tools for enhancing risk stratification and personalising BC management in clinical urology practice. Their integration into multidisciplinary workflows has the potential to improve outcomes and reduce overtreatment.