Changes in planned disease management after piflufolastat F18 PET/CT in men with biochemically recurrent prostate cancer and low PSA levels: A secondary analysis of results from the CONDOR study

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Background: Piflufolastat F 18 is a PSMA-targeted radiopharmaceutical approved in the US for imaging prostate cancer (PCa) patients both at the time of initial staging and at disease recurrence. In a phase 3 study of patients with biochemically recurrent (BCR) PCa, we reported that nearly two-thirds (63.9%; 131/205) of participants had a change in their intended disease management plan based on pre- and post-piflulfolastat F 18 PET/CT management questionnaires (MMQs) completed by the treating physicians. The clinical utility of piflufolastat F 18 scanning in men with very low/low PSA levels (<0.5 ng/mL) and a detection rate of ~36% has not been previously described. Here we report the changes in intended management in this subset of patients. Methods: Men ≥18 years of age with a rising PSA after definitive PCa therapy and negative or equivocal imaging were enrolled. A single ~9 mCi (333 MBq) dose of piflufolastat F 18 was administered followed by PET/CT from mid-thigh through skull vertex 1-2 hours later. Prior to scanning, the treating physicians completed a pre-PET MMQ to document the initial intended management plan for their patients based on available clinical information including baseline conventional imaging results. After PET, they completed a post-PET MMQ and recorded the management plan in light of PET findings. Treatment recommendations that differed from the pre-scan recommendations were reported as changes in the intended management plan. Results: 208 men (median PSA 0.8 ng/mL [range 0.17-98.45], n=202) underwent piflufolastat F 18-PET/CT. 200 evaluable patients had both a baseline PSA value and completed MMQs. Of 131 patients with a recorded change in intended management, 127 had an evaluable baseline PSA level. Of the 69 patients with baseline PSA levels ≤0.5ng/mL, 27 (39.1%) recorded a change in intended disease management based on positive (n=20) or negative (n=7) PET, including salvage local to systemic therapy (n=15); systemic to local therapy (n=3); observation to treatment (n=5); and treatment to observation (n=4). An additional 15 patients (21.7%) had recommended bidirectional change in management (e.g., salvage RT+ADT) and are excluded in this report. Specific treatment intensification/de-intensification plans are under investigation. Conclusions: The frequency of changes in intended disease management observed in BCR PCa patients with low baseline PSA levels (≤0.5ng/mL) was 39.1%. Both negative and positive PET/CT results impacted treatment recommendations and can provide useful and actionable information. Clinical trial information: NCT02981368 .

Prospective study of a 17-GENE RT-PCR-based assay for prediction of high risk pathology at radical prostatectomy

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Background: A biopsy-based 17 gene tissue-based RTPCR assay (Oncotype Dx Genomic Prostate Score, GPS) has been validated in retrospective cohorts as a predictor of adverse pathology and biochemical recurrence in prostate cancer (PCa) patients who underwent radical prostatectomy (RP). The National Comprehensive Cancer Network (NCCN) recommends that men with pathologic Gleason Score (pGS) > 8, pT3+, and/or Lymph Node positive disease (i.e. high risk surgical pathology, HRSP) consider adjuvant therapy after RP. We report herein on GPS at biopsy as a predictor of HRSP in men presenting with clinically low-risk PCa. Methods: As part of an ongoing observational study of GPS (N = 1200), we performed an exploratory analysis in men who elected RP as initial disease management. Descriptive statistics were reported. Binary logistic regression was performed to determine the association between GPS and HRSP. The odds ratio (OR) per 20 GPS units and 95% confidence interval (CI) were reported. All analyses were conducted with SAS 9.4. Results: Of the 1,200 patients enrolled in the study, 150 (21 sites) selected RP for initial management; 122 (19 sites) had biopsy and surgical pathology data available for analysis.Median age was 63 (range 50-79) years, with 38% > 65 yrs. There were 72 (59%), 39 (32%), and 11 (9%) patients who had NCCN Intermediate-, Low-, and Very Low-Risk disease, respectively Median GPS was 30 (IQR 20-40, range 8-82). Biological risk (GPS+NCCN) differed from NCCN risk in 28 cases (23%). At surgery, 29 /122 (24%) of patients had HRSP; of these, 1 had NCCN Very Low-, 8 had Low-, and 20 had Intermediate-Risk cancer at diagnosis. GPS was a significant predictor of HRSP (OR per 20 GPS units: 2.1; 95% CI: [1.2, 4.0]; p-value 0.02). No other clinical factor was significantly associated with HRSP. GPS remained significant after adjusting for NCCN risk group (OR per 20 GPS units: 2.0; 95% CI 1.1-3.8, p = 0.03). Incorporation of GPS increased the AUC for prediction of HRSP from 0.57 (NCCN alone) to 0.65 (NCCN + GPS) Conclusions: GPS derived from biopsy tissue is an independent predictor of HRSP. This information may be valuable in treatment planning for men with clinically low risk PCa who are at risk for HRSP.

Treatment patterns after the use of the 17-gene Genomic Prostate Score assay in Veterans newly diagnosed with clinically low-risk prostate cancer

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Background: Active surveillance (AS) is a recommended management approach for low risk prostate cancer (PCa). Studies have shown high rates of AS in the Veterans Administration (VA), but concerns about missing aggressive disease lead to variation between centers. The 17-gene Genomic Prostate Score (GPS) has been validated to predict likelihood of favorable pathology (LFP) in men with clinically low risk PCa. This study compared treatment patterns before and after introduction of the GPS to determine if the assay influenced treatment patterns. Methods: Men newly diagnosed with PCa who met NCCN criteria for very low (VL), low (L), or intermediate (INT) risk PCa were eligible. Chart review of men across 6 VA medical centers (VAMCs) established treatment in untested patients in 2013-2014. In 2015, Veterans at the same VAMCs were offered the assay in a prospective study measuring treatment recommendations before and after the assay and treatment implemented based on chart review. Results: There were 200 men in the untested cohort. Characteristics: age (median = 66, range:43-83), Gleason Score (GS) (3+3:64%, 3+4:37%), PSA (mean = 6.6, range:0.7-20), NCCN risk (VL:18%, L:37%, INT:46%). There were 190 men in the prospective study with complete data. NCCN risk group: age (median = 66, range:50-85), GS (3+3:74%, 3+4:26%), PSA (mean = 6.4, range:0.4-18.1), VL:22%, L:43%, INT:35%. GPS ranged from 0-61 and LFP ranged from 38%-91%. GPS identified 24 patients who had more favorable pathology and 13 patients who had less favorable pathology than would be expected using NCCN alone. 62% of untested Veterans pursued AS compared to 74% of tested Veterans. AS increases between untested and tested cohorts were 1% in VL, 16% in L, and 3% in INT. Conclusions: Both untested and tested patients had clinical characteristics representative of low risk PCa in the VA. Use of AS increased in tested Veterans compared to untested, with the largest increases observed in NCCN low risk patients. The 17-gene assay used biological information to provide refined risk estimates in tested Veterans, assisting physicians in appropriately identifying candidates for AS or immediate treatment.

Selected applications of balloon dissection

Historically, balloons have been used in surgery for a variety of applications. Over the past decades, balloons have been used by surgeons for retaining means (Foley catheter), extraction and occlusion (Fogarty catheter), tamponade (Sengstaken-Blakemore tube) as well as other uses such as dilation and calibration. The pioneering efforts of Gauer and Kieturakis have broadened the use of balloons for a new surgical application - dissection. An important feature of balloon dissection is that it allows the surgeon to create a new operative working space in which a surgical procedure can be performed. Currently, a particularly useful working space is the region immediately outside the peritoneum, frequently termed the extraperitoneal space. A variety of procedures can be performed laparoscopically in the extraperitoneal space such as herniorrhaphy, bladder neck suspension, lymph node dissection, and varicocelectomy.