Diagnostic Performance of 18F-rhPSMA-7.3 PET in Men with Newly Diagnosed High-Risk Prostate Cancer and Negative Conventional Imaging

PURPOSE/OBJECTIVE(S)

The LIGHTHOUSE study (NCT04186819) evaluated high affinity radio hybrid (rh) prostate-specific membrane antigen (PSMA)-targeted PET radiopharmaceutical, 18F-rhPSMA-7.3, in patients across a range of prostate cancer (PCa) risk groups. Here, we report findings from a subgroup with high/very high-risk PCa who had no evidence of nodal or metastatic disease on conventional imaging.

MATERIALS/METHODS

Treatment-naïve patients scheduled for radical prostatectomy (RP) plus pelvic lymph node (PLN) dissection underwent PET 50-70 min after IV administration of 296 MBq 18F-rhPSMA-7.3. Local readers interpreted the scans prior to RP (performed ≤60 d post-PET) and ahead of a blinded read by 3 central readers. If the local read indicated M1 disease, verification (biopsy, surgery, or confirmatory follow-up imaging) of PET-positive M1 lesions was attempted before treatment. The present analysis evaluates the 18F-rhPSMA-7.3 sensitivity and specificity for detection of PLN metastases in all high/very high-risk patients with negative conventional imaging at baseline who underwent 18F-rhPSMA-7.3 PET and subsequent surgery. Histopathology was used as the standard of truth (SoT). Additionally, the M1 verified detection rate (VDR; % of patients with true positive (TP) M1 lesions using histopathology or follow-up imaging as SoT out of all patients scanned) was assessed in an extended population of all patients who had 18F-rhPSMA-7.3 PET regardless of surgery.

RESULTS

The sensitivity and specificity for PLN detection among 174 men with very/high-risk PCa and negative conventional imaging ranged from 24-33% and 92-96%, respectively, across readers (Table 1a). Across readers, M1 lesions were identified in 28-51 of the 197 patients in the extended population, giving an overall M1 detection rate of 14-26%. Of the identified lesions, 16-25 were successfully verified (predominantly using follow-up imaging as SoT) as TP, providing a M1 VDR of 8.1-13% (Table 1).

CONCLUSION

18F-rhPSMA-7.3 PET provides clinically useful information on the presence of both N1 and M1 disease prior to surgery in high/very high-risk PCa patients who were staged N0 M0 on conventional imaging. Specifically, up to 13% of such patients had verified TP M1 lesions. 18F-rhPSMA-7.3 may guide treatment, potentially helping such patients avoid ultimately futile surgery.

Oncologic outcomes among Black and White men with grade group 4 or 5 (Gleason score 8-10) prostate cancer treated primarily by radical prostatectomy

BACKGROUND

The aim of this study was to describe pathologic and short-term oncologic outcomes among Black and White men with grade group 4 or 5 prostate cancer managed primarily by radical prostatectomy.

METHODS

This was a multi-institutional, observational study (2005-2015) evaluating radical prostatectomy outcomes by self-identified race. Descriptive analysis was performed via nonparametric statistical testing to compare baseline clinicopathologic data. Univariable and multivariable time-to-event analyses were performed to assess biochemical recurrence (BCR), metastasis, cancer-specific mortality (CSM), and overall survival between Black and White men.

RESULTS

In total, 1662 men were identified with grade group 4 or 5 prostate cancer initially managed by radical prostatectomy. Black men represented 11.3% of the cohort (n = 188). Black men were younger, demonstrated a longer time from diagnosis to surgery, and were at a lower clinical stage (all P < .05). Black men had lower rates of pT3/4 disease (49.5% vs 63.5%; P < .05) but higher rates of positive surgical margins (31.6% vs 26.5%; P = .14) on pathologic evaluation. There was no difference in BCR, CSM, or overall survival over a median follow-up of 40.7 months. Black men had a lower 5-year cumulative incidence of metastasis-free survival (93.6%; 95% confidence interval [CI], 86.5%-97.0%) in comparison with White men (85.8%; 95% CI, 83.1%-88.0%), which did not persist in an age-adjusted analysis.

CONCLUSIONS

Black and White men with high-grade prostate cancer at diagnosis demonstrated similar oncologic outcomes when they were managed by primary radical prostatectomy. Our findings suggest that racial disparities in prostate cancer mortality are not related to differences in the efficacy of extirpative therapy.

Intermittent fasting for the prevention of cardiovascular disease

BACKGROUND

Cardiovascular disease (CVD) is the leading cause of death worldwide. Lifestyle changes are at the forefront of preventing the disease. This includes advice such as increasing physical activity and having a healthy balanced diet to reduce risk factors. Intermittent fasting (IF) is a popular dietary plan involving restricting caloric intake to certain days in the week such as alternate day fasting and periodic fasting, and restricting intake to a number of hours in a given day, otherwise known as time-restricted feeding. IF is being researched for its benefits and many randomised controlled trials have looked at its benefits in preventing CVD.

OBJECTIVES

To determine the role of IF in preventing and reducing the risk of CVD in people with or without prior documented CVD.

SEARCH METHODS

We conducted our search on 12 December 2019; we searched CENTRAL, MEDLINE and Embase. We also searched three trials registers and searched the reference lists of included papers. Systematic reviews were also viewed for additional studies. There was no language restriction applied.

SELECTION CRITERIA

We included randomised controlled trials comparing IF to ad libitum feeding (eating at any time with no specific caloric restriction) or continuous energy restriction (CER). Participants had to be over the age of 18 and included those with and without cardiometabolic risk factors. Intermittent fasting was categorised into alternate-day fasting, modified alternate-day fasting, periodic fasting and time-restricted feeding.

DATA COLLECTION AND ANALYSIS

Five review authors independently selected studies for inclusion and extraction. Primary outcomes included all-cause mortality, cardiovascular mortality, stroke, myocardial infarction, and heart failure. Secondary outcomes include the absolute change in body weight, and glucose. Furthermore, side effects such as headaches and changes to the quality of life were also noted. For continuous data, pooled mean differences (MD) (with 95% confidence intervals (CIs)) were calculated. We contacted trial authors to obtain missing data. We used GRADE to assess the certainty of the evidence.  MAIN RESULTS: Our search yielded 39,165 records after the removal of duplicates. From this, 26 studies met our criteria, and 18 were included in the pooled analysis. The 18 studies included 1125 participants and observed outcomes ranging from four weeks to six months. No studies included data on all-cause mortality, cardiovascular mortality, stroke, myocardial infarction, and heart failure at any point during follow-up. Of quantitatively analysed data, seven studies compared IF with ab libitum feeding, eight studies compared IF with CER, and three studies compared IF with both ad libitum feeding and CER. Outcomes were reported at short term (≤ 3 months) and medium term (> 3 months to 12 months) follow-up. Body weight was reduced with IF compared to ad libitum feeding in the short term (MD -2.88 kg, 95% CI -3.96 to -1.80; 224 participants; 7 studies; low-certainty evidence). We are uncertain of the effect of IF when compared to CER in the short term (MD -0.88 kg, 95% CI -1.76 to 0.00; 719 participants; 10 studies; very low-certainty evidence) and there may be no effect in the medium term (MD -0.56 kg, 95% CI -1.68 to 0.56; 279 participants; 4 studies; low-certainty evidence). We are uncertain about the effect of IF on glucose when compared to ad libitum feeding in the short term (MD -0.03 mmol/L, 95% CI -0.26 to 0.19; 95 participants; 3 studies; very-low-certainty of evidence) and when compared to CER  in the short term: MD -0.02 mmol/L, 95% CI -0.16 to 0.12; 582 participants; 9 studies; very low-certainty; medium term: MD 0.01, 95% CI -0.10 to 0.11; 279 participants; 4 studies; low-certainty evidence). The changes in body weight and glucose were not deemed to be clinically significant. Four studies reported data on side effects, with some participants complaining of mild headaches. One study reported on the quality of life using the RAND SF-36 score. There was a modest increase in the physical component summary score.

AUTHORS' CONCLUSIONS

Intermittent fasting was seen to be superior to ad libitum feeding in reducing weight. However, this was not clinically significant. There was no significant clinical difference between IF and CER in improving cardiometabolic risk factors to reduce the risk of CVD. Further research is needed to understand the safety and risk-benefit analysis of IF in specific patient groups (e.g. patients with diabetes or eating disorders) as well as the effect on longer-term outcomes such as all-cause mortality and myocardial infarction.

Does the clinical effectiveness of Mitraclip compare with surgical repair for mitral regurgitation?

BACKGROUND

Surgical repair of the mitral valve has long been the established therapy for degenerative mitral regurgitation (MR). Newer transcatheter methods over the last decade, such as the MitraClip, serve to restore mitral function with reduced procedural burden and enhanced recovery. This study aims to compare the shortterm and midterm outcomes of MitraClip insertion with surgical repair for MR.

METHODS

A systematic review of the literature was conducted for studies comparing outcomes between surgical repair and MitraClip. The initial search returned 1850 titles, from which 12 studies satisfied the inclusion criteria (one randomized controlled trial and 11 retrospective studies).

RESULTS

The final analysis comprised 4219 patients (MitraClip 1210; surgery 3009). Operative mortality was not different between the groups (odds ratio [OR] = 1.63, 95% confidence interval [CI]: [0.63-4.23]; p = .317). Length of hospital stay was significantly shorter in the MitraClip group (standardized mean difference [SMD] = 0.882, 95% CI: [0.77-0.99]; p < .001) with considerable heterogeneity (I²  > 90%; p < .001). The rate of reoperation on the mitral valve was lower in the surgical group (OR = 0.392; 95% CI: [0.188-0.817]; p = .012) as was the rate of MR recurrence grade moderate or above (OR = 0.29; 95% CI: [0.19-0.46]; p < .001) during midterm follow up. Long term survival (4-5 years) was also similar between both groups (hazard ratio = 0.70; 95% CI: [0.35-1.41]; p = .323).

CONCLUSIONS

This study highlights the superior midterm durability of surgical valve repair for MR compared with the MitraClip.

Transforming the Perioperative Treatment Paradigm in Non-Metastatic RCC-A Possible Path Forward

In 2017, there is no adjuvant systemic therapy proven to increase overall survival in non-metastatic renal cell carcinoma (RCC). The anti-PD-1 antibody nivolumab improves overall survival in metastatic treatment refractory RCC and is generally tolerable. Mouse solid tumor models have revealed a benefit with a short course of neoadjuvant PD-1 blockade compared to adjuvant therapy. Two ongoing phase 2 studies of perioperative nivolumab in RCC patients have shown preliminary feasibility and safety with no surgical delays or complications. The recently opened PROSPER RCC trial (A Phase 3 RandOmized Study Comparing PERioperative Nivolumab vs. Observation in Patients with Localized Renal Cell Carcinoma Undergoing Nephrectomy; EA8143) will examine if the addition of perioperative nivolumab to radical or partial nephrectomy can improve clinical outcomes in patients with high risk localized and locally advanced RCC. With the goal of increasing cure and recurrence-free survival (RFS) rates in non-metastatic RCC, we are executing a three-pronged, multidisciplinary approach of presurgical priming with nivolumab followed by resection and adjuvant PD-1 blockade. We plan to enroll 766 patients with clinical stage ≥T2 or node positive M0 RCC of any histology in this global, randomized, unblinded, phase 3 National Clinical Trials Network study. The investigational arm will receive two doses of nivolumab 240 mg IV prior to surgery followed by adjuvant nivolumab for 9 months. The control arm will undergo the current standard of care: surgical resection followed by observation. Patients are stratified by clinical T stage, node positivity, and histology. The trial is powered to detect a 14.4% absolute benefit in the primary endpoint of RFS from the ASSURE historical control of 55.8% to 70.2% at 5 years (HR = 0.70). The study is also powered to detect a significant overall survival benefit (HR 0.67). Key safety, feasibility, and quality of life endpoints are incorporated. PROSPER RCC exemplifies team science with a host of planned correlative work to investigate the impact of the baseline immune milieu and changes after neoadjuvant priming on clinical outcomes.

Clinical decision making using teleradiology in urology

OBJECTIVE

Using a personal computer-based teleradiology system, we compared accuracy, confidence, and diagnostic ability in the interpretation of digitized radiographs to determine if teleradiology-imported studies convey sufficient information to make relevant clinical decisions involving urology. Variables of diagnostic accuracy, confidence, image quality, interpretation, and the impact of clinical decisions made after viewing digitized radiographs were compared with those of original radiographs.

MATERIALS AND METHODS

We evaluated 956 radiographs that included 94 IV pyelograms, four voiding cystourethrograms, and two nephrostograms. The radiographs were digitized and transferred over an Ethernet network to a remote personal computer-based viewing station. The digitized images were viewed by urologists and graded according to confidence in making a diagnosis, image quality, diagnostic difficulty, clinical management based on the image itself, and brief patient history. The hard-copy radiographs were then interpreted immediately afterward, and diagnostic decisions were reassessed. All analog radiographs were reviewed by an attending radiologist.

RESULTS

Ninety-seven percent of the decisions made from the digitized radiographs did not change after reviewing conventional radiographs of the same case. When comparing the variables of clinical confidence, quality of the film on the teleradiology system versus analog films, and diagnostic difficulty, we found no statistical difference (p > .05) between the two techniques. Overall accuracy in interpreting the digitized images on the teleradiology system was 88% by urologists compared with that of the attending radiologist's interpretation of the analog radiographs. However, urologists detected findings on five (5%) analog radiographs that had been previously unreported by the radiologist.

CONCLUSION

Viewing radiographs transmitted to a personal computer-based viewing station is an appropriate means of reviewing films with sufficient quality on which to base clinical decisions. Our focus was whether decisions made after viewing the transmitted radiographs would change after viewing the hard-copy images of the same case. In 97% of the cases, the decision did not change. In those cases in which management was altered, recommendation of further imaging studies was the most common factor.