The Role of Prostate-specific Membrane Antigen Positron Emission Tomography/Computed Tomography in Primary Staging of Selected Renal Tumours: Initial Experience in a Multicentre Cohort

BACKGROUND

Accurate primary staging of renal cancer with conventional imaging is challenging. Prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) may serve to improve the accuracy of renal cancer staging.

OBJECTIVE

To determine clinicopathological and management differences for primary renal cancer staged with PSMA PET/CT in comparison to conventional imaging.

DESIGN, SETTING, AND PARTICIPANTS

We conducted a retrospective cohort study of PSMA PET/CT scans performed for primary staging of renal cancer and incidental renal lesions at three sites in Brisbane, Australia between June 2015 and June 2020. Clinical characteristics, imaging, and histopathology were reviewed.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Clinicopathological and management differences according to staging modality (PSMA PET/CT, conventional imaging) were assessed. Descriptive statistics were used to report demographics and clinical parameters. Nonparametric methods were used for statistical analysis. Fisher's exact test was used for comparison of small-cell size categorical variables.

RESULTS AND LIMITATIONS

From a total of 120 PSMA PET/CT scans, 61 were included (52 staging, 9 incidental) for predominantly males (74%) with a mean age of 65.1 yr (standard deviation 12.0). Most primary lesions (40/51) were clear-cell renal cell carcinoma (ccRCC; 98% PSMA-avid), eight were non-ccRCC (75% PSMA-avid), and three were non-RCC (oncocytoma; 67% PSMA-avid). PSMA PET identified a greater number of presumed metastatic lesions than conventional imaging (195 vs 160). A management change was observed for 32% of patients (20% major, 12% minor). Limitations include the retrospective design and selection bias, lack of blinding to PSMA reporting, and the use of different PSMA radiotracers.

CONCLUSIONS

PSMA PET/CT detected more metastases than conventional imaging and most renal cancers were PSMA-avid, resulting in a management change for one-third of the patients.

PATIENT SUMMARY

We looked at a newer type of scan called PSMA PET/CT for first staging of kidney cancer. We found that this detects more metastasis and helps in decisions on changes in treatment for some patients. This type of imaging is a useful addition to conventional scans in tricky cases and may help in better selection of suitable treatments, but more studies are required.

The risk of prostate cancer on incidental finding of an avid prostate uptake on 2-deoxy-2-[18F]fluoro-d-glucose positron emission tomography/computed tomography for non-prostate cancer-related pathology: A single centre retrospective study

Objective

To review the risk of prostate cancer (PCa) in men with incidentally reported increased intraprostatic uptake at 2-deoxy-2-[18F]fluoro-d-glucose positron emission tomography/computed tomography (18F-FDG PET/CT) ordered at Department of Urology, The Wesley Hospital, Brisbane, QLD, Australia for non-PCa related pathology.

Methods

Retrospective analysis of consecutive men between August 2014 and August 2019 presenting to a single institution for 18F-FDG PET/CT for non-prostate related conditions was conducted. Men were classified as benign, indeterminate, or malignant depending of the results of prostate-specific antigen (PSA), PSA velocity, biopsy histopathology, and three-Tesla (3 T) multiparametric MRI (mpMRI) Prostate Imaging Reporting and Data System score, or gallium-68-prostate-specific membrane antigen (68Ga-PSMA) PET/CT results.

Results

Three percent (273/9122) of men demonstrated 18F-FDG avidity within the prostate. Eighty-five percent (231/273) were further investigated, including with PSA tests (227/231, 98.3%), 3 T mpMRI (68/231, 29.4%), 68Ga-PSMA PET/CT (33/231, 14.3%), and prostate biopsy (57/231, 24.7%). Results were considered benign in 130/231 (56.3%), indeterminate in 31/231 (13.4%), and malignant in 70/231 (30.3%). PCa was identified in 51/57 (89.5%) of the men who proceeded to biopsy, including 26/27 (96.3%) men with Prostate Imaging Reporting and Data System scores 4-5 mpMRI and six men with a positive 68Ga-PSMA PET/CT. The most common Gleason score on biopsy was greater than or equal to 4+5 (14/51, 27.5%). 68Ga-PSMA PET/CT was concordant with the 18F-FDG findings in 26/33 (78.8%). All 13 men with a positive concordant 18F-FDG, 3 T mpMRI, and 68Ga-PSMA PET/CT had PCa on biopsy. There was no statistically significant difference in the 18F-FDG maximum standardized uptake value between the benign or malignant groups (5.7 vs. 6.1; p=0.580).

Conclusion

In this study, after an incidental finding of an avid intraprostatic lesion on 18F-FDG PET/CT, 70 of the 231 cases (30.3%; 0.8% of the entire cohort) had results consistent with PCa, most commonly as Gleason score greater than or equal to 4+5 disease. Unless there is limited life expectancy due to competing medical co-morbidity, men with an incidental finding of intraprostatic uptake on 18F-FDG should be further investigated using principles of PCa detection.

Development and External Validation of a Novel Nomogram to Predict the Probability of Pelvic Lymph-node Metastases in Prostate Cancer Patients Using Magnetic Resonance Imaging and Molecular Imaging with Prostate-specific Membrane Antigen Positron Emission Tomography

BACKGROUND

Preoperative assessment of the probability of pelvic lymph-node metastatic disease (pN1) is required to identify patients with prostate cancer (PCa) who are candidates for extended pelvic lymph-node dissection (ePLND).

OBJECTIVE

To develop a novel intuitive prognostic nomogram for predicting pathological lymph-node (pN) status in contemporary patients with primary diagnosed localized PCa, using preoperative clinical and histopathological parameters, magnetic resonance imaging (MRI), and prostate-specific membrane antigen (PSMA) positron emission tomography (PET).

DESIGN, SETTING, AND PARTICIPANTS

In total, 700 eligible patients who underwent robot-assisted radical prostatectomy and ePLND were included in the model-building cohort. The external validation cohort consisted of 305 surgically treated patients. Logistic regression with backward elimination was used to select variables for the Amsterdam-Brisbane-Sydney nomogram.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Performance of the final model was evaluated using the area under the receiver operating characteristic curve (AUC), calibration plots, and decision-curve analyses. Models were subsequently validated in an external population.

RESULTS AND LIMITATIONS

The Amsterdam-Brisbane-Sydney nomogram included initial prostate-specific antigen value, MRI T stage, highest biopsy grade group (GG), biopsy technique, percentage of systematic cores with clinically significant PCa (GG ≥2), and lymph-node status on PSMA-PET. The AUC for predicting pN status was 0.81 (95% confidence interval [CI] 0.78-0.85) for the final model. On external validation, the Amsterdam-Brisbane-Sydney nomogram showed superior discriminative ability to the Briganti-2017 and Memorial Sloan Kettering Cancer Center (MSKCC) nomograms (AUC 0.75 [95% CI 0.69-0.81] vs 0.67 [95% CI 0.61-0.74] and 0.65 [95% CI 0.58-0.72], respectively; p < 0.05), and similar discriminative ability to the Briganti-2019 nomogram (AUC 0.78 [95% CI 0.71-0.86] vs 0.80 [95% CI 0.73-0.86]; p = 0.76). The Amsterdam-Brisbane-Sydney nomogram showed excellent calibration on external validation, with an increased net benefit at a threshold probability of ≥4%.

CONCLUSIONS

The validated Amsterdam-Brisbane-Sydney nomogram performs superior to the Briganti-2017 and MSKCC nomograms, and similar to the Briganti-2019 nomogram. Furthermore, it is applicable in all patients with newly diagnosed unfavorable intermediate- and high-risk PCa.

PATIENT SUMMARY

We developed and validated the Amsterdam-Brisbane-Sydney nomogram for the prediction of prostate cancer spread to lymph nodes before surgery. This nomogram performs similar or superior to all presently available nomograms.

Clinicopathologic Significance of Anterior Prostate Cancer: Comparison With Posterior Prostate Cancer in the Era of Multiparametric Magnetic Resonance Imaging

Anterior prostate cancer (APC) has been considered an indolent tumor, most commonly arising in the transition zone (TZ). More recently, detection of APC has been facilitated through multiparametric magnetic resonance imaging and improved biopsy techniques, enabling earlier detection. The pathologic features and clinical significance of pure APC in a large contemporary series of well-characterized tumors have, to date, not been elucidated. Cases with APC defined as cancer present anterior to the urethra only were identified from 1761 consecutive radical prostatectomy specimens accessioned between January 2015 and August 2016. The clinicopathologic features of these cases were compared with those of pure posterior prostate cancer (PPC) and the features of anterior peripheral zone (APZ) cancers were compared with those of TZ cancers. In addition, the tumor series from 2015 to 2016 was compared with a cohort of 1054 patients accessioned before the utilization of multiparametric magnetic resonance imaging in the routine workup of patients with prostate cancer. In the 2015-2016 series, there were 188 (10.7%) patients with APC compared with 5.4% in the series from the pre-multiparametric magnetic resonance imaging era. No difference was observed between APC and PPC with regards to patient age or mean serum prostate-specific antigen at presentation. Mean tumor volume and positive surgical margin (PSM) rates were significantly higher in APC. In contrast, PPC was more commonly high grade with more frequent extraprostatic extension (EPE). None of the cases of APC had infiltration of the seminal vesicle or lymph node involvement, in contrast to PPC, with almost 14% of cases in each category. The 3- and 5-year biochemical recurrence-free survival was significantly higher in APC when compared with PPC, although this was not retained on multivariable analysis which included tumor location. On division of APCs according to anatomic zone of origin, 45% were APZ cancer and 37% TZ cancer. On comparison of APZ and TZ cancers, there were no significant differences in mean age and serum prostate-specific antigen at presentation as well as tumor volume, Gleason score, and PSM rate. High-grade malignancy (Gleason score >3 + 4=7) was seen in 26% of TZ cancers which compared with 44% of APZ cancers and 56% of PPC cancers. The rate of EPE was significantly higher in APZ when compared with TZ cancer ( P< 0.0005); however, the biochemical recurrence rate was not significantly different between the groups. The prevalence of APC in radical prostatectomy specimens has increased in recent times, in association with earlier detection at a stage amenable to curative surgical treatment. APC, when compared with PPC, is less commonly high grade with less frequent EPE, despite the APC group having larger tumors and a higher PSM rate at presentation. However, not all anterior cancers are indolent. Anterior cancers are more commonly seen in the APZ than the TZ and APZ cancers appear more locally aggressive than TZ cancers.

Diagnostic Accuracy of Multiparametric Magnetic Resonance Imaging to Detect Residual Prostate Cancer Following Irreversible Electroporation-A Multicenter Validation Study

BACKGROUND

Accurate monitoring following focal treatment of prostate cancer (PCa) is paramount for timely salvage treatment or retreatment.

OBJECTIVE

To evaluate the diagnostic accuracy of multiparametric magnetic resonance imaging (mpMRI) to detect residual PCa in the short-term follow-up of focal treatment with irreversible electroporation (IRE) using transperineal or transrectal template ± targeted biopsies.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective international multicenter study of men with biopsy-proven PCa, treated with focal IRE, and followed by mpMRI (index-test) and template biopsies (reference-test) between February 2013 and January 2021, was conducted.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of mpMRI were calculated for in- and outfield residual disease based on two definitions of significant PCa: University College London (UCL) 1-International Society of Urological Pathology (ISUP) ≥3 or ISUP ≥1 with maximum cancer core length (MCCL) ≥6 mm, and UCL2-ISUP ≥2 or ISUP ≥1 with MCCL ≥4 mm.

RESULTS AND LIMITATIONS

A total of 303 patients from five focal therapy centers were treated with primary IRE. The final analysis was performed on 217 men (median age 67, median prostate-specific antigen 6.2, 81% ISUP 2/3) who underwent both mpMRI and template biopsies. Multiparametric MRI missed 38/57 (67%) positive biopsy locations (UCL1) in 22 patients. Sensitivity, specificity, PPV, and NPV of mpMRI to detect whole gland residual disease (UCL1) were 43.6% (95% confidence interval [CI]: 28-59), 80.9% (95% CI: 75-86), 33.3% (95% CI: 21-47), and 86.7% (95% CI: 81-91), respectively. Based on UCL2, sensitivity, specificity, PPV, and NPV were 35.8% (95% CI: 25-48), 82.0% (95% CI: 75-88), 47.1% (95% CI: 34-61), and 74.1% (95% CI: 67-80), respectively. Limitations are the retrospective nature and short follow-up.

CONCLUSIONS

The diagnostic accuracy of mpMRI to detect residual clinically significant PCa following IRE was low. Follow-up template biopsies should be performed, regardless of mpMRI results.

PATIENT SUMMARY

We investigated the accuracy of magnetic resonance imaging (MRI) to detect residual prostate cancer after treatment with irreversible electroporation. The accuracy of MRI is insufficient, and we emphasize the importance of confirmatory prostate biopsies.

Urothelial Carcinoma and Prostate-specific Membrane Antigen: Cellular, Imaging, and Prognostic Implications

CONTEXT

Staging, restaging, and surveillance of urothelial carcinoma (UC) is challenging due to suboptimal accuracy of standard of care imaging modalities. Prostate-specific membrane antigen (PSMA) imaging may serve to improve characterisation of UC.

OBJECTIVE

To appraise available literature regarding cellular, imaging, and prognostic implications of PSMA for UC.

EVIDENCE ACQUISITION

A systematic review was performed considering all available literature (including conference abstracts) published from 1990 to 2020 and reported according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines following registration in PROSPERO (CRD42020186744). All relevant texts relating to immunohistochemical analysis and PSMA-based imaging in UC were included and collated. Additionally, FOLH1 (gene encoding PSMA) expression according to The Cancer Genome Atlas (TCGA) database was analysed as well as according to consensus and TCGA molecular classification subtypes and subsequently compared with clinical outcomes.

EVIDENCE SYNTHESIS

PSMA expression across UC tumour tissue was heterogeneous (0-100%) but appeared to decrease with increased grade and stage. The TCGA analysis demonstrated loss of FOLH1 expression with increasing T stage (p = 0.0180) and N stage (p = 0.0269), and reduced FOLH1 expression was associated with worse disease-free survival. PSMA expression in UC neovasculature was variable but mostly increased (44-100%). Eleven reports of PSMA-based imaging for UC were identified, reporting on 18 patients. PSMA positron emission tomography (PET) imaging was positive in 17 out of 18 patients. The included literature review data were limited by mostly low-quality, retrospective studies.

CONCLUSIONS

Tissue PSMA, or FOLH1 expression, may inversely be associated with pathological and survival outcomes in localised UC. PSMA PET imaging may improve detection of metastatic disease and response to systemic therapy due to PSMA expression in neovasculature. Available evidence is limited; thus, larger, prospective studies are required to confirm early results and define populations that benefit most.

PATIENT SUMMARY

In this systematic review, we assess the potential role of prostate-specific membrane antigen in urothelial cancer. We found that its utility is in expression of blood vessels surrounding metastasis. We conclude that it may be beneficial in detecting metastasis and response to systemic therapies.

Determining risk factors for symptomatic urinary tract infection following trial of void: A retrospective analysis

Objective:

To investigate the incidence and risk factors for symptomatic urinary tract infection (UTI) following trial of void (TOV) to guide patient selection for antibiotic prophylaxis.

Methods:

A retrospective study considered all patients who underwent successful TOV across two separate 12-month periods at a tertiary hospital. Routine prophylactic antibiotics were not administered.

Results:

The 183 patients included were mostly men (91.3%) aged ⩾ 65 years (78.7%). Thirty-seven (20.3%) had recent urological surgery. The incidence of UTI following TOV was 12.6% (23/183); median duration of onset was 3 days (interquartile range = 2–9). Cystitis was most common (17/183; 9.3%), while four patients (2.2%) suffered urosepsis. There were no singular statistically significant risk factors for increasing the risk of UTI following TOV, however, ⩾ 2 risk factors showed numerically higher odds of UTI compared to ⩽ 1 risk factor (15.6% vs 4.2%; odds ratio = 4.24, 95% confidence interval = 0.96–18.80, p = 0.058). Atypical organisms resistant to most oral antibiotics were predominantly cultured, however, 89% sensitivity to ciprofloxacin was observed.

Conclusion:

The incidence of UTI following TOV was higher than anticipated. Reliable identification of at-risk patients for antibiotic prophylaxis is likely to be complicated. Further research is needed to confirm patient selection prior to confirmatory trials.

Level of evidence:

2b

Primary tumour PSMA intensity is an independent prognostic biomarker for biochemical recurrence-free survival following radical prostatectomy

Purpose

The prognostic value of PSMA intensity on PSMA PET/CT due to underlying biology and subsequent clinical implications is an emerging topic of interest. We sought to investigate whether primary tumour PSMA PET intensity contributes to pre- and post-operative prediction of oncological outcomes following radical prostatectomy.

Methods

We performed a retrospective cohort study of 848 men who underwent all of multiparametric MRI (mpMRI), transperineal prostate biopsy, and ⁶⁸ Ga-PSMA PET/CT prior to radical prostatectomy. PSMA intensity, quantified as maximum standard uptake value (SUVmax), and other clinical variables were considered relative to post-operative biochemical recurrence-free survival (BRFS) using Cox regression and Kaplan–Meier analysis.

Results

After a median follow-up of 41 months, 219 events occurred; the estimated 3-year BRFS was 79% and the 5-year BRFS was 70%. Increasing PSMA intensity was associated with less favourable BRFS overall (Log rank p < 0.001), and within subgroups of Gleason score category (Log rank p < 0.03). PSMA intensity was significantly associated with shorter time to biochemical recurrence, after adjusting for pre-operative (HR per 5-unit SUVmax increase = 1.15) and post-operative (HR per 5-unit SUVmax increase = 1.10) parameters.

Conclusion

These results in a large series of patients confirm PSMA intensity to be a novel, independent prognostic factor for BRFS.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00259-022-05756-2.

The role of dual tracer PSMA and FDG PET/CT in renal cell carcinoma (RCC) compared to conventional imaging: A multi-institutional case series with intra-individual comparison

PURPOSE

The objective of this study was to perform an intra-individual dual tracer comparison of Fluorodeoxyglucose (FDG) and Prostate Specific Membrane Antigen (PSMA) computed tomography (CT)/Positron Emission Tomography (PET) against standard of care (SOC) imaging for the characterisation, staging and restaging of renal cell carcinoma (RCC).

METHODS

A multicentre retrospective cohort study was performed at 3 major tertiary referral institutions in Brisbane, Australia between 2015 and 2020. All patients who underwent both PSMA and FDG PET/CT following SOC imaging for investigation of RCC were identified. Clinical details, imaging characteristics and histopathology were collected prior to univariate statistical analysis.

RESULTS

Eleven patients who underwent dual tracer PET/CT were included. Mean age was 65.5 years (SD 8.8). Most patients were male (64%) with clear cell morphology (91%). The indication for dual tracer PET was staging (36%) and restaging after radical/partial nephrectomy (64%). Primary tumour assessment showed mixed avidity patterns (concordant 40%, discordant favouring PSMA 20%, and FDG 40%). Metastatic disease assessment showed concordant avidity in 6 patients (55%), concordant negative in 3 (27%), and discordant uptake favouring PSMA. PET outperformed SOC imaging for assessment of metastatic disease in 5 patients (45%) and equivalent for the remainder. A change in management was noted in three cases (27%).

CONCLUSION

Dual tracer FDG and PSMA PET/CT for assessment of primary and metastatic RCC were mostly concordant. PET imaging outperformed conventional imaging and led to a change in management for 1 in 4 patients. Further studies with larger samples sizes are required to validate these findings and identify characteristics to guide patient selection for selective or dual tracer use.

Intraductal Carcinoma of the Prostate: Extreme Nuclear Size Is Not a Diagnostic Parameter

High-grade prostatic adenocarcinoma involving duct/acinar structures is labeled intraductal carcinoma of the prostate (IDCP). As numerous studies have shown that IDCP is associated with high stage disease with a significant negative impact on cancer-specific survival, accurate diagnosis is crucial to ensure appropriate patient management. The definition of IDCP recommended by 2016 World Health Organization (WHO) classification suggests that cases of IDCP with micropapillary or loose cribriform architecture without comedonecrosis should have cells with ≥6× nuclear enlargement. It is unclear how this size criterion was derived and which of the parameters of nuclear size (nuclear diameter, nuclear surface area, or nuclear perimeter) it relates to. To evaluate the extent of nuclear enlargement in IDCP, we performed morphometric analyses relating to each of these parameters in 100 radical prostatectomy specimens. One hundred nuclei from foci of IDCP and 50 nuclei from foci of normal luminal epithelium were examined for each patient. Diagnosis of IDCP was based on cells with definite features of carcinoma present within duct/acinar structures. Comparing the means of each of the parameters between IDCP cells and benign luminal cells, there was a statistically significant enlargement in nuclear perimeter (P<0.0005), nuclear area (P<0.0005), and nuclear diameter (P<0.0005); however, the difference in mean nuclear size was limited to factors of 1.3×, 1.6×, and 1.3×, respectively. Three patients each had rare large nuclei (largest perimeter 45, 45, and 44 μm; maximum nuclear area 135, 136, and 136 μm2; and the largest diameter 18 µm in each). For these rare cells, the nuclear size difference, when compared with benign nuclei was; nuclear perimeter 2.0×, 2.1×, and 2.1×; nuclear area 3.6×, 3.8×, and 3.8×; and nuclear maximum diameter 3.0×, 2.5×, and 2.5×. The definition of nuclear enlargement of ≥6× was not reached in any of our cases, all of which clearly showed features of duct invasive carcinoma. In these cases, reliance on nuclear size criteria would have resulted in underdiagnosis of IDCP. This is of concern as failure to recognize IDCP, particularly in needle biopsies, could lead to delays in the timely treatment of aggressive high-grade prostate cancer, resulting in cancer progression and suboptimal patient oncological outcomes.

External Validation and Addition of Prostate-specific Membrane Antigen Positron Emission Tomography to the Most Frequently Used Nomograms for the Prediction of Pelvic Lymph-node Metastases: an International Multicenter Study

BACKGROUND

Different nomograms exist for the preoperative prediction of pelvic lymph-node metastatic disease in individual patients with prostate cancer (PCa). These nomograms do not incorporate modern imaging techniques such as prostate-specific membrane antigen (PSMA) positron emission tomography (PET).

OBJECTIVE

To determine the predictive performance of the Briganti 2017, Memorial Sloan Kettering Cancer Center (MSKCC), and Briganti 2019 nomograms with the addition of PSMA-PET in an international, multicenter, present-day cohort of patients undergoing robot-assisted radical prostatectomy (RARP) and extended pelvic lymph-node dissection (ePLND) for localized PCa.

DESIGN, SETTING, AND PARTICIPANTS

All 757 eligible patients who underwent a PSMA-PET prior to RARP and ePLND in three reference centers for PCa surgery between January 2016 and November 2020 were included.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Performance of the three nomograms was assessed using the receiver operating characteristic curve-derived area under the curve (AUC), calibration plots, and decision curve analyses. Subsequently, recalibration and addition of PSMA-PET to the nomograms were performed.

RESULTS AND LIMITATIONS

Overall, 186/757 patients (25%) had pelvic lymph-node metastatic (pN1) disease on histopathological examination. AUCs of the Briganti 2017, MSKCC, and Briganti 2019 nomograms were 0.70 (95% confidence interval [95% CI]: 0.64-0.77), 0.71 (95% CI: 0.65-0.77), and 0.76 (95% CI: 0.71-0.82), respectively. PSMA-PET findings showed a significant association with pN1 disease when added to the nomograms (p < 0.001). Addition of PSMA-PET substantially improved the discriminative ability of the models yielding cross-validated AUCs of 0.76 (95% CI: 0.70-0.82), 0.77 (95% CI: 0.72-0.83), and 0.82 (95% CI: 0.76-0.87), respectively. In decision curve analyses, the addition of PSMA-PET to the three nomograms resulted in increased net benefits.

CONCLUSIONS

The addition of PSMA-PET to the previously developed nomograms showed substantially improved predictive performance, which suggests that PSMA-PET is a likely future candidate for a modern predictive nomogram.

PATIENT SUMMARY

Different tools have been developed to individualize the prediction of prostate cancer spread to lymph nodes before surgery. We found that the inclusion of modern imaging (prostate-specific membrane antigen positron emission tomography) improved substantially the overall performance of these prediction tools.

High-dose vitamin D supplementation to prevent prostate cancer progression in localised cases with low-to-intermediate risk of progression on active surveillance (ProsD): protocol of a phase II randomised controlled trial

INTRODUCTION

Active surveillance (AS) for patients with prostate cancer (PC) with low risk of PC death is an alternative to radical treatment. A major drawback of AS is the uncertainty whether a patient truly has low risk PC based on biopsy alone. Multiparametric MRI scan together with biopsy, appears useful in separating patients who need curative therapy from those for whom AS may be safe. Two small clinical trials have shown short-term high-dose vitamin D supplementation may prevent PC progression. There is no substantial evidence for its long-term safety and efficacy, hence its use in the care of men with PC on AS needs assessment. This protocol describes the ProsD clinical trial which aims to determine if oral high-dose vitamin D supplementation taken monthly for 2 years can prevent PC progression in cases with low-to-intermediate risk of progression.

METHOD AND ANALYSIS

This is an Australian national multicentre, 2:1 double-blinded placebo-controlled phase II randomised controlled trial of monthly oral high-dose vitamin D supplementation (50 000 IU cholecalciferol), in men diagnosed with localised PC who have low-to-intermediate risk of disease progression and are being managed by AS. This trial will assess the feasibility, efficacy and safety of supplementing men with an initial oral loading dose of 500 000 IU cholecalciferol, followed by a monthly oral dose of 50 000 IU during the 24 months of AS. The primary trial outcome is the commencement of active therapy for clinical or non-clinical reason, within 2 years of AS.

ETHICS AND DISSEMINATION

This trial is approved by Bellberry Ethics Committee (2016-06-459). All results will be reported in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

ACTRN12616001707459.

Staging of renal cell carcinoma: current progress and potential advances

Formal staging classifications for renal cell carcinoma (RCC) were first proposed in 1978 and were incorporated into the Tumour, Nodes, Metastases (TNM) system initially published by the Union Internationale Contre le Cancer (UICC) in 1978. There has been a gradual evolution of grading criteria through six separate editions of the UICC TNM Classification, with the latest edition being published in 2016. Somewhat surprisingly there were no changes to the T category criteria from the 2009 to the 2016 editions of the classification, although an erratum has subsequently been published that incorporated the minor changes included in the eighth edition of the TNM Classification published by the American Joint Committee on Cancer. Localised tumours are staged according to the size of the primary tumour, with the TNM classification recognising that these tumours may exceed 10 cm in diameter. This is unfortunate as there is good evidence to demonstrate that, for clear cell RCC, virtually all tumours >7 cm in diameter and a substantial proportion of tumours <7 cm in diameter, show extra-renal spread. Infiltration of tumour beyond the renal capsule into the peri-renal fat is also categorised as T3a, however the clinical importance of this remains unclear. The classification of microvascular invasion within the renal sinus requires clarification, as does the prognostic significance of tumour in small vessels within the kidney.

Understanding the diagnosis of prostate cancer

Prostate cancer continues to be the most commonly diagnosed cancer, and the second leading cause of cancer death among Australian men. Prostate-specific antigen testing is personalised (not dichotomous in nature) and its interpretation should take into account the patient's age, symptoms, previous results and medication (eg, 5-α reductase inhibitors such as dutasteride). Multiparametric magnetic resonance imaging of the prostate has been proven to have a 93% sensitivity for detecting clinically significant prostate cancer. It has the potential to decrease unnecessary prostate biopsies by around 27%. International Society of Urological Pathology (ISUP) grade 1 (Gleason score 6) has been shown to have very little, if any, risk of metastasis ISUP grade 1 (Gleason score 3 +3 = 6) and low percentage ISUP grade 2 (Gleason score 3 + 4 [< 10%] = 7) can be offered active surveillance. The goal of active surveillance is to defer treatment but is still curative when required. With better imaging (magnetic resonance imaging and emerging prostate-specific membrane antigen positron emission tomography-computed tomography) and transperineal prostate biopsy, more men can be offered screening after discussion of risks and benefits, knowing that overdiagnosis has been minimised and radical treatment is reserved for only the most aggressive disease.

Histological comparison between predictive value of preoperative 3-T multiparametric MRI and 68 Ga-PSMA PET/CT scan for pathological outcomes at radical prostatectomy and pelvic lymph node dissection for prostate cancer

OBJECTIVE

To evaluate the ability of preoperative multiparametric magnetic resonance imaging (mpMRI) and a gallium-68 prostate-specific membrane antigen positron emission tomography/computed tomography (⁶⁸ Ga-PSMA PET/CT) scan to predict pathological outcomes and also identify a group of men with a <5% risk of histological pelvic lymph node metastasis (LNM) at pelvic lymph node dissection (PLND) performed during a robot-assisted laparoscopic radical prostatectomy (RALP) for prostate cancer. We then aimed to compare these results to known risk calculators for LNM, including the Cancer of the Prostate Risk Assessment (CAPRA) score, Memorial Sloan Kettering Cancer Centre (MSKCC) and Briganti nomograms.

PATIENTS AND METHODS

Between July 2014 and September 2019 only men who had both a preoperative mpMRI and staging ⁶⁸ Ga-PSMA PET/CT at our institution followed by a RALP with PLND referred to a single specialist uropathology laboratory were considered for inclusion. The data were collected retrospectively prior to February 2019 and in a prospective manner thereafter. A model was built to allocate probabilities of the men with a negative ⁶⁸ Ga-PSMA PET/CT scan having a <5% risk of histologically LNM at RALP based on the preoperative radiological staging.

RESULTS

A total of 233 consecutive men met the inclusion criteria of which 58 men (24.9%) had a LNM identified on PLND histology. The median (range) International Society of Urological Pathology (ISUP) Grade was 5 (1-5) and the median (range) prostate-specific antigen level was 7.4 (1.5-72) ng/mL. The median (range) number of resected lymph nodes was 16 (1-53) and the median (range) number of positive nodes identified on histology was 2 (1-22). Seminal vesicle invasion on mpMRI was more common in node-positive men than in the absence of LNM (31% vs 12%). The maximum standardised uptake value of the primary tumour on ⁶⁸ Ga-PSMA PET/CT was higher in men with LNM (median 9.2 vs 7.2, P = 0.02). Suspected LNM were identified in 42/233 (18.0%) men with ⁶⁸ Ga-PSMA PET/CT compared with 22/233 (9.4%) men with mpMRI (P = 0.023). The positive and negative predictive value for ⁶⁸ Ga-PSMA PET/CT was 66.7% and 84.3% respectively, compared to 59.1% and 78.7% for mpMRI. A predictive model showed only two men (4.2%) with a negative preoperative ⁶⁸ Ga-PSMA PET/CT would be positive for a histological LNM if they are ISUP Grade < 5 and Prostate Imaging-Reporting and Data System (PI-RADS) <5; or ISUP Grade 5 with PI-RADS < 4. An inspection of three additional variables: CAPRA score, MSKCC and Briganti nomograms did not improve the predictive probability for this group. However, of the 61 men with ISUP Grade 4-5 malignancy and also a PI-RADS 5 mpMRI, 20 (32.8%) men had a microscopic LNM despite a negative preoperative ⁶⁸ Ga-PSMA PET/CT.

CONCLUSION

Preoperative ⁶⁸ Ga-PSMA/PET CT was more sensitive in identifying histological pelvic LNM than 3-T mpMRI. Men with a negative ⁶⁸ Ga-PSMA PET/CT have a lower risk of LNM than predicted with CAPRA scores or MSKCC and Briganti nomograms. We identified that the combination of a negative preoperative ⁶⁸ Ga-PSMA PET/CT, ISUP biopsy Grade <5 and PI-RADS <5 prostate mpMRI, or an ISUP Grade 5 with PI-RADS <4 on mpMRI was associated with a <5% risk of a LNM. The addition of CAPRA scores, MSKCC and Briganti nomograms did not improve the predictive probability within this model. Conversely, men with ISUP Grade 4-5 malignancy associated with a PI-RADS 5 prostate mpMRI had a >30% risk of microscopic LNM despite a negative preoperative ⁶⁸ Ga-PSMA PET/CT and this high-risk group would appear suitable for an extended PLND at the time of a radical prostatectomy.

Granular necrosis: a distinctive form of cell death in malignant tumours

Foci of necrosis are frequently seen in malignant tumours and may be due to a variety of causes. Different types of necrosis are given various names based upon their morphological features and presumed pathogenesis, such as coagulative, liquefactive and fibrinoid necrosis. Here, we propose the term 'granular necrosis' (GN) for a specific form of tumour necrosis characterised by the presence of well-defined necrotic foci being sharply demarcated from adjacent viable tumour. A constant feature is loss of architecture resulting in an amorphous necrotic mass containing granular nuclear and cytoplasmic debris, without an associated neutrophilic infiltrate. There is usually extensive karyorrhexis, which in larger tumours is more prominent at the periphery. These foci are often microscopic but may range up to several millimetres or larger in size. This distinctive form of necrosis has been erroneously given a variety of names in the literature including coagulative necrosis and microscopic necrosis, which on the basis of the aforementioned gross and microscopic findings is inappropriate. It is apparent that this is a specific form of necrosis, hence the descriptive term 'granular necrosis' that differentiates this form of necrosis from other types. The presence of GN is recognised as occurring in a variety of tumour types, being commonly seen in renal cell carcinoma, where it has been shown to have independent prognostic significance. In some epithelial and stromal tumours of the uterus, the presence of GN also has prognostic significance and is a defining feature for the differentiation of uterine leiomyoma and leiomyosarcoma. The pathogenesis of GN is unresolved. It does not show the features of apoptosis and in recent studies has been shown to have some of the molecular changes associated with necroptosis.

Intraductal carcinoma of the prostate is an aggressive form of invasive carcinoma and should be graded

Infiltration of the prostatic ducts by prostatic adenocarcinoma occurs relatively frequently, being most commonly associated with high grade disease. It is now recognised that intraductal carcinoma of the prostate (IDCP) has an associated poor prognosis and this is reflected in its histological, molecular and immunohistochemical features. The current recommendation of the World Health Organization is that IDCP not be taken into consideration when grading prostate adenocarcinoma. It is apparent that Gleason did not differentiate between IDCP and stromal invasive carcinoma when developing and validating his grading system, and recent studies suggest that the incorporation of IDCP grading into the overall grading of the specimen provides additional prognostic information.

A prospective study of psychological distress after prostate cancer surgery

BACKGROUND

Men treated for prostate cancer experience heightened psychological distress and have an increased risk of suicide. Management of this distress and risk is crucial for quality urological care.

OBJECTIVE

To identify risk indicators for poorer trajectories of psychological adjustment and health-related quality of life (QoL) after surgery for localised prostate cancer.

DESIGN, SETTING, AND PARTICIPANTS

Patients were newly diagnosed with localised prostate cancer scheduled for surgical treatment. Patients were assessed at baseline (pre-surgery) and 6 weeks, 3 months, 6 months, 12 months, and 24 months post-surgery.

MEASUREMENTS

Assessment measures included sociodemographics, domain-specific and health-related QoL, and psychological distress. Mixed effects regression models were used to analyse the data.

RESULTS AND LIMITATIONS

A total of 233 patients provided data for this analysis (M_age = 60 years, standard deviation [SD] = 4.02; M_PSA = 7.37 ng/mL). At baseline, the prevalence of high psychological distress was 28% reducing to 21% at 24 months. Before treatment, younger age, more comorbidities, and worse bowel function were related to greater psychological distress; and younger age and better urinary, sexual, and bowel function were related to better health-related QoL. By contrast, for changes over time, only bowel function was important with better bowel function predicting decreasing psychological distress for men.

CONCLUSIONS

Regular distress screening is indicated over the 24 months after surgery for localised prostate cancer. Care pathways for men with prostate cancer need also to respond to age-specific concerns and health problems associated with comorbidities in aging men. Focussed symptom control for bowel bother should be a priority.

Design and Clinical Verification of Surface-Enhanced Raman Spectroscopy Diagnostic Technology for Individual Cancer Risk Prediction

The use of emerging nanotechnologies, such as plasmonic nanoparticles in diagnostic applications, potentially offers opportunities to revolutionize disease management and patient healthcare. Despite worldwide research efforts in this area, there is still a dearth of nanodiagnostics which have been successfully translated for real-world patient usage due to the predominant sole focus on assay analytical performance and lack of detailed investigations into clinical performance in human samples. In a bid to address this pressing need, we herein describe a comprehensive clinical verification of a prospective label-free surface-enhanced Raman scattering (SERS) nanodiagnostic assay for prostate cancer (PCa) risk stratification. This contribution depicts a roadmap of (1) designing a SERS assay for robust and accurate detection of clinically validated PCa RNA targets; (2) employing a relevant and proven PCa clinical biomarker model to test our nanodiagnostic assay; and (3) investigating the clinical performance on independent training ( n = 80) and validation ( n = 40) cohorts of PCa human patient samples. By relating the detection outcomes to gold-standard patient biopsy findings, we established a PCa risk scoring system which exhibited a clinical sensitivity and specificity of 0.87 and 0.90, respectively [area-under-curve of 0.84 (95% confidence interval: 0.81-0.87) for differentiating high- and low-risk PCa] in the validation cohort. We envision that our SERS nanodiagnostic design and clinical verification approach may aid in the individualized prediction of PCa presence and risk stratification and may overall serve as an archetypical strategy to encourage comprehensive clinical evaluation of nanodiagnostic innovations.

Robot-assisted laparoscopic prostatectomy versus open radical retropubic prostatectomy: 24-month outcomes from a randomised controlled study

BACKGROUND

Previous trials have found similar early outcomes after robot-assisted laparoscopic prostatectomy and open radical retropubic prostatectomy. We report functional and oncological postoperative outcomes up to 24 months after surgery for these two surgical techniques.

METHODS

In this randomised controlled phase 3 study, men who had newly diagnosed clinically localised prostate cancer and who had chosen surgery as their treatment approach, and were aged between 35 years and 70 years were eligible and recruited from the Royal Brisbane and Women's Hospital (Brisbane, QLD, Australia). Participants were randomly assigned (1:1) to have either robot-assisted laparoscopic prostatectomy or open radical retropubic prostatectomy. Randomisation was computer generated and occurred in blocks of ten. This was an open trial; however, study investigators involved in data analysis were masked to each patient's surgical treatment. Primary outcomes were urinary function (urinary domain of Expanded Prostate Cancer Index Composite [EPIC]) and sexual function (sexual domain of EPIC and International Index of Erectile Function Questionnaire [IIEF]) at 6 months, 12 months, and 24 months and oncological outcome (biochemical recurrence and imaging evidence of progression). The trial was powered to assess health-related and domain-specific quality-of-life outcomes over 24 months. All analyses were done on a per-protocol basis. The trial was registered with the Australian New Zealand Clinical Trials Registry, number ACTRN12611000661976.

FINDINGS

Between Aug 23, 2010, and Nov 25, 2014, 326 men were enrolled, of whom 163 were randomly assigned to robot-assisted laparoscopic prostatectomy and 163 to open radical retropubic prostatectomy. 18 withdrew (12 assigned to radical retropubic prostatectomy and six assigned to robot-assisted laparoscopic prostatectomy); thus, 151 in the radical retropubic prostatectomy group and 157 in the robot-assisted laparoscopic prostatectomy group proceeded to surgery. At the 24-month follow-up time point, 150 men remained in the robot-assisted laparoscopic prostatectomy group and 146 remained in the open radical retropubic prostatectomy group. Urinary function scores did not differ significantly between robot-assisted laparoscopic prostatectomy and open radical retropubic prostatectomy at 6 months post-surgery (88·68 [95% CI 86·79-90·58] vs 88·45 [86·54-90·36]; p1<0·0001, p2<0·0001), 12 months post-surgery (90·76 [88·89-92·62] vs 91·53 [90·07-92·98]; p1<0·0001, p2<0·0001), or 24 months post-surgery (91·33 [89·64-93·03] vs 90·86 [89·01-92·70]; p1<0·0001, p2<0·0001). Sexual function scores were not significantly different between robot-assisted laparoscopic prostatectomy and open radical retropubic prostatectomy at 6 months post-surgery (EPIC: 37·40 [33·60-41·19] vs 38·63 [34·76-42·49], p1=0·0001, p2<0·0001; IIEF: 29·75 [26·66-32·84] vs 29·78 [26·41-33·16], p1<0·0001, p2<0·0001), 12 months post-surgery (EPIC: 42·28 [38·05-46·51] vs 42·51 [38·29-46·72], p1<0·0001, p2<0·0001; IIEF: 33·10 [29·59-36·61] vs 33·50 [29·87-37·13], p1=0·0002, p2<0·0001), or 24 months post-surgery (EPIC: 45·70 [41·17-50·23] vs 46·90 [42·20-51·60], p1=0·0003, p2<0·0001; IIEF: 33·95 [30·11-37·78] vs 33·89 [29·82-37·96], p1=0·0003, p2=0·0004). Equivalence testing on the difference between the proportion of biochemical recurrences between the two groups (13 [9%] in the open radical retropubic prostatectomy group vs four [3%] in the robot-assisted laparoscopic prostatectomy group) showed that equality between the two techniques could not be established based on a 90% CI with a prespecified margin of 10%. However, a superiority test showed that the two proportions were significantly different (p=0·0199). Equivalence testing on the proportion of patients who had imaging evidence of progression revealed that the two groups were not significantly different (p=0·2956).

INTERPRETATION

Robot-assisted laparoscopic prostatectomy and open radical retropubic prostatectomy yielded similar functional outcomes at 24 months. We advise caution in interpreting the oncological outcomes of our study because of the absence of standardisation in postoperative management between the two trial groups and the use of additional cancer treatments. Clinicians and patients should view the benefits of a robotic approach as being largely related to its minimally invasive nature.

FUNDING

Cancer Council Queensland.

Robot-assisted laparoscopic prostatectomy versus open radical retropubic prostatectomy: early outcomes from a randomised controlled phase 3 study

BACKGROUND

The absence of trial data comparing robot-assisted laparoscopic prostatectomy and open radical retropubic prostatectomy is a crucial knowledge gap in uro-oncology. We aimed to compare these two approaches in terms of functional and oncological outcomes and report the early postoperative outcomes at 12 weeks.

METHOD

In this randomised controlled phase 3 study, men who had newly diagnosed clinically localised prostate cancer and who had chosen surgery as their treatment approach, were able to read and speak English, had no previous history of head injury, dementia, or psychiatric illness or no other concurrent cancer, had an estimated life expectancy of 10 years or more, and were aged between 35 years and 70 years were eligible and recruited from the Royal Brisbane and Women's Hospital (Brisbane, QLD). Participants were randomly assigned (1:1) to receive either robot-assisted laparoscopic prostatectomy or radical retropubic prostatectomy. Randomisation was computer generated and occurred in blocks of ten. This was an open trial; however, study investigators involved in data analysis were masked to each patient's condition. Further, a masked central pathologist reviewed the biopsy and radical prostatectomy specimens. Primary outcomes were urinary function (urinary domain of EPIC) and sexual function (sexual domain of EPIC and IIEF) at 6 weeks, 12 weeks, and 24 months and oncological outcome (positive surgical margin status and biochemical and imaging evidence of progression at 24 months). The trial was powered to assess health-related and domain-specific quality of life outcomes over 24 months. We report here the early outcomes at 6 weeks and 12 weeks. The per-protocol populations were included in the primary and safety analyses. This trial was registered with the Australian New Zealand Clinical Trials Registry (ANZCTR), number ACTRN12611000661976.

FINDINGS

Between Aug 23, 2010, and Nov 25, 2014, 326 men were enrolled, of whom 163 were randomly assigned to radical retropubic prostatectomy and 163 to robot-assisted laparoscopic prostatectomy. 18 withdrew (12 assigned to radical retropubic prostatectomy and six assigned to robot-assisted laparoscopic prostatectomy); thus, 151 in the radical retropubic prostatectomy group proceeded to surgery and 157 in the robot-assisted laparoscopic prostatectomy group. 121 assigned to radical retropubic prostatectomy completed the 12 week questionnaire versus 131 assigned to robot-assisted laparoscopic prostatectomy. Urinary function scores did not differ significantly between the radical retropubic prostatectomy group and robot-assisted laparoscopic prostatectomy group at 6 weeks post-surgery (74·50 vs 71·10; p=0·09) or 12 weeks post-surgery (83·80 vs 82·50; p=0·48). Sexual function scores did not differ significantly between the radical retropubic prostatectomy group and robot-assisted laparoscopic prostatectomy group at 6 weeks post-surgery (30·70 vs 32·70; p=0·45) or 12 weeks post-surgery (35·00 vs 38·90; p=0·18). Equivalence testing on the difference between the proportion of positive surgical margins between the two groups (15 [10%] in the radical retropubic prostatectomy group vs 23 [15%] in the robot-assisted laparoscopic prostatectomy group) showed that equality between the two techniques could not be established based on a 90% CI with a Δ of 10%. However, a superiority test showed that the two proportions were not significantly different (p=0·21). 14 patients (9%) in the radical retropubic prostatectomy group versus six (4%) in the robot-assisted laparoscopic prostatectomy group had postoperative complications (p=0·052). 12 (8%) men receiving radical retropubic prostatectomy and three (2%) men receiving robot-assisted laparoscopic prostatectomy experienced intraoperative adverse events.

INTERPRETATION

These two techniques yield similar functional outcomes at 12 weeks. Longer term follow-up is needed. In the interim, we encourage patients to choose an experienced surgeon they trust and with whom they have rapport, rather than a specific surgical approach.

FUNDING

Cancer Council Queensland.