Exploring the accuracy of multiparametric MRI in prostate cancer staging: An institutional retrospective study

e17056

Background: Multiparametric Magnetic Resonance Imaging (mpMRI) has been increasingly utilized in prostate cancer (PCa) diagnosis and staging. While there is Level 1 data supporting MRI utility in identifying clinically significant PCa and guiding PCa diagnosis, there is little data on its ability to predict surgical outcomes and its utility as a staging study. We aimed to evaluate the accuracy of mpMRI in predicting common surgical pathology outcomes in patients who underwent radical prostatectomy (RP). Methods: Men who underwent either open radical prostatectomy (ORP) or robotic assisted laparoscopic prostatectomy (RALP) for prostate adenocarcinoma from January-December 2021 at a single tertiary level care academic medical center were identified. Chart review for relevant patient demographics, mpMRI related variables and final surgical pathology was completed. In patients who had pre-operative mpMRI, we evaluated the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of mpMRI in predicting relevant surgical outcomes, including presence of pT2N0 organ confined disease (OCD), extracapsular extension (ECE), seminal vesicle invasion (SVI), lymph node involvement (LNI), and bladder neck invasion (BNI). Results: 168 eligible patients were identified in a 12-month period. The mean age was 63.5±6.24 years and mean Prostate Specific Antigen (PSA) was 11.4±23.7, with 166 (98.8%) patients undergoing RALP and 115 (68.5%) having pre-operative mpMRI. Median GGG was 2 in both MRI and CT subsets (p = 0.580), and patients who had pre-op MRI were more likely to have higher PSA (12.7 ±28.1 vs 8.38± 6.32, p = 0.073) and clinically node positive disease (p < 0.001) than those with CT. However, there was no significant difference in final surgical pathology or positive surgical margin rates between these two groups. On subset analysis of the MRI subset, Table summarizes the sensitivity, specificity, PPV, and NPV of pre-op MRI to predict OCD, ECE, SVI, LNI, and BNI. While specificity of pre-op MRI was adequate for all outcomes (89.1-100%), sensitivity (2.9-49.2%), PPV (40-100%), and NPV (56.3-94.3%) were poor. Conclusions: At present, pre-op MRI of the prostate does not appear to be accurate in its ability to predict important pathologic outcomes at the time of radical prostatectomy and should be used cautiously as a local staging tool. More work is needed before MRI can be used as a reliable staging tool for PCa.[Table: see text]

EA8185: Phase 2 study of bladder-sparing chemoradiation (chemoRT) with durvalumab in clinical stage III, node-positive urothelial carcinoma (INSPIRE), an ECOG-ACRIN/NRG collaboration

TPS4617

Background: Patients [pts] withlymph node positive (LN+), non-metastatic bladder cancer (BC) have a better prognosis than those with metastatic (M1) disease. However, this population is under-represented in advanced bladder trials and ineligible for bladder-sparing trials. Therefore, there have been no larger prospective trials establishing the standard of care in LN+ BC. Given the promise of immunotherapy in advanced BC and potential synergy between immunotherapy and radiation, INSPIRE was designed to determine the role of concurrent and adjuvant durvalumab (durva) in this patient population when treated with induction chemotherapy (IC) followed by concurrent chemoRT. Methods: This is a randomized phase II study that is enrolling BC pts with stage III [N1-3 M0], pure or mixed urothelial cancer. Pts must have received ≥3 cycles of IC [either before or after registration, prior to randomization] without progression. LN+ is defined as radiologically LN ≥1.0 cm in short axis, with or without biopsy prior to IC. As long as pts do not progress on induction chemotherapy, they will be randomized to chemoRT+/- durva using 5 stratification factors (Simon Pocock minimization method) a) IC prior vs. post registration b) cisplatin vs non-cisplatin regimen during RT c) LN size d) response to IC e) extent of TURBT. Pts on the chemoRT+durva arm will get chemotherapy per physician choice + IMRT + 3 x doses of Q3wk durva for 6.5-8 wks, whereas those on the control arm will get chemoRT alone. The primary end point is clinical complete response [CR], defined as no radiologically measurable disease in the LNs and negative cystoscopy and bladder biopsy 8-10 weeks post-chemoRT +/- durva. Pts on the chemoRT + durva arm who have a CR or clinical benefit ( > T0 and ≤T2 in bladder per cystoscopy, biopsy + CR/PR/SD in LN by imaging) will get adjuvant Q4wk durva for 9 doses, while those on the chemoRT arm will undergo observation. Secondary end points include OS, PFS, bladder-intact event-free survival, rate of toxicity and salvage cystectomy. This study is designed to detect an improvement of 25% in clinical CR between both arms (37.5% to 62.5%). A total accrual of 114 pts (in order to enroll 92 evaluable pts) will provide 81% power to detect this difference using a Fisher’s exact test (assuming 10% drop out + anticipating that 20% chemotherapy-naïve pts will progress post IC). We are banking blood and primary tumor tissue pre- and post-chemoRT in both groups. The study was activated in August 2020 and accrual is ongoing. We expanded eligibility to include N3 in 9/2021. INSPIRE is the first prospective study designed for only LN+ BC and will define both short-term and long-term outcomes for bladder sparing in this patient population and has the potential to define a new treatment strategy for stage III BC. Clinical trial information: NCT04216290.

EA8185: Phase 2 study of bladder-sparing chemoradiation (chemoRT) with durvalumab in clinical stage III, node positive urothelial carcinoma (INSPIRE), an ECOG-ACRIN/NRG collaboration

TPS594

Background: Patients [pts] withlymph node positive (LN+), non-metastatic bladder cancer (BC) have a better prognosis than those with metastatic (M1) disease. However, this population is under-represented in advanced bladder trials and ineligible for bladder-sparing trials. Therefore, there have been no larger prospective trials establishing the standard of care in LN+ BC. Given the promise of immunotherapy in advanced BC and potential synergy between immunotherapy and radiation, INSPIRE was designed to determine the role of concurrent and adjuvant durvalumab (durva) in this patient population when treated with induction chemotherapy (IC) followed by concurrent chemoRT. Methods: This is a randomized phase II study that is enrolling BC pts with stage III [N1-3 M0], pure or mixed urothelial cancer. Pts must have received ≥3 cycles of IC [either before or after registration, prior to randomization] without progression. LN+ is defined as radiologically LN ≥1.0 cm in short axis, with or without biopsy prior to IC. As long as pts do not progress on induction chemotherapy, they will be randomized to chemoRT+/- durva using 5 stratification factors (Simon Pocock minimization method) a) IC prior vs. post registration b) cisplatin vs non-cisplatin regimen during RT c) LN size d) response to IC e) extent of TURBT. Pts on the chemoRT+durva arm will get chemotherapy per physician choice + IMRT + 3 x doses of Q3wk durva for 6.5-8 wks, whereas those on the control arm will get chemoRT alone. The primary end point is clinical complete response [CR], defined as no radiologically measurable disease in the LNs and negative cystoscopy and bladder biopsy 8-10 weeks post-chemoRT +/- durva. Pts on the chemoRT + durva arm who have a CR or clinical benefit (>T0 and ≤T2 in bladder per cystoscopy, biopsy + CR/PR/SD in LN by imaging) will get adjuvant Q4wk durva for 9 doses, while those on the chemoRT arm will undergo observation. Secondary end points include OS, PFS, bladder-intact event-free survival, rate of toxicity and salvage cystectomy. This study is designed to detect an absolute improvement of 25% in clinical CR between both arms (37.5% to 62.5%). The accrual goal is 114, assuming 10% drop out + anticipating that 20% chemotherapy-naïve pts will progress post IC, and 92 evaluable pts that will provide 81% power to detect this difference using a Fisher’s exact test. We are banking blood and primary tumor tissue pre- and post-chemoRT in both groups. The study was activated in August 2020 and accrual is ongoing. We expanded eligibility to include N3 in 9/2021. INSPIRE is the first prospective study designed for only LN+ BC and will define both short-term and long-term outcomes for bladder sparing in this patient population and has the potential to define a new treatment strategy for stage III BC. Clinical trial information: NCT04216290.

The international penile advanced cancer trial (InPACT): The first phase III trial for squamous carcinoma of the penis with regional lymph node metastases

TPS7

Background: Penis cancer is a rare but potentially fatal disease. A limited body of evidence exists on which to base the majority of management decisions for patients with regional nodal metastases. Five-year survival for patients with a single involved inguinal lymph node treated with surgery alone is approximately 80%, whilst it ranges from 0 to 12% for patients with pelvic node involvement (N3). Additional strategies are required for the management regionally-advanced disease. InPACT (NCT02305654) aims to determine prospectively the relative benefits and sequencing of surgery, chemotherapy, and chemoradiotherapy in the management of patients with penis cancer who present with palpable or radiologically evident inguinal lymph node metastases. InPACT addresses the following questions: Is there a role for neoadjuvant therapy and, if so, which of the two options (chemotherapy or chemoradiotherapy) before surgery gives superior outcomes? Among patients whose inguinal node histology predicts a high risk of recurrence, does prophylactic pelvic lymph node dissection (PLND) plus chemoradiation to the inguinal and pelvic fields improve survival compared to chemoradiation alone? Methods: A Bayesian trial design aims to include a wide population of patients and incorporates two randomisations: InPACT-neoadjuvant and InPACT-pelvis. Participants are stratified by disease burden (extent of nodal involvement), by the presence or absence of high-risk radiological features, and by GFR. Participants with high disease burden where neoadjuvant treatment is thought to be indicated are randomised to neoadjuvant chemotherapy or neoadjuvant chemoradiotherapy. Participants with intermediate disease burden are randomised to one of 3 arms: Surgery alone or neoadjuvant chemoradiotherapy followed by surgery, or neoadjuvant chemotherapy prior to surgery. Participants in the low-burden group proceed directly to surgery. Participants with postoperative inguinal node pathology that shows high-risk features may then proceed to InPACT-pelvis where randomisation is between adjuvant chemoradiotherapy ± PLND for those not previously treated with chemoradiotherapy & between PLND & observation for those previously treated with neoadjuvant chemoradiotherapy. The study aims to recruit 200 participants. The primary outcome measure is overall survival, with secondary outcome measures of disease-specific survival, disease-free survival, and freedom from locoregional recurrence and distant metastasis. Feasibility, toxicity, the type/extent of surgical complications, and quality of life will be assessed as secondary endpoints for all the InPACT treatment arms. To October 2021, 65 participants have been recruited with centres open in the UK, US and Canada. Clinical trial information: NCT02305654.

Risk of secondary malignancies after pelvic radiation: A population-based analysis

478

Background: Radiation therapy (RT) is an integral component of the multimodal therapy of pelvic malignancies, either as primary treatment or in combination with surgical resection. In addition to local treatment effects on nearby pelvic organs, RT has been established to be a risk factor for delayed secondary malignancies. In this study, we examine the rate of any secondary malignancies following RT for primary pelvic malignancies, with a specific emphasis on secondary pelvic malignancies Methods: Using the SEER (Surveillance, Epidemiology, and Ends Results) database, we retrospectively examined 2,102,192 patients with primary pelvic malignancies (prostate, bladder, uterine, rectal, cervical). For each disease site, we compared the rate of all secondary malignancies in radiated patients to non-radiated patients. Secondary malignancies were then stratified as pelvic and non-pelvic, in order to determine the local effect of RT on malignancy risk. Results: A total of 2,102,192 patients were examined (1,189,108 prostate, 315,026 bladder, 88,809 cervical, 249,535 uterine, 259,714 rectal). A total of 113,322 patients developed secondary malignancies after RT (Table), with 26,299 developing secondary pelvic malignancies after RT (18,411 prostate, 1,026 bladder, 1,410 cervical, 2,179 uterine, 3,273 rectal) (Table). The overall relative risk (RR) of RT on developing a secondary malignancy was 1.79 (1.77-1.80 CI, P<0.0001), particularly in patients with prostate (RR 2.57), uterine (RR 1.24) and cervical cancer (1.09). The overall RR of RT on developing a secondary pelvic malignancy was 2.09 (2.06-2.13 CI, P<0.0001), particularly in patients with bladder (RR 6.90), prostate (RR 2.74), and uterine cancer (RR 1.21). Conclusions: Radiation treatment for pelvic malignancies increases the risk of developing secondary malignancies over the patient’s lifetime. Further work needs to done to identify at risk populations.[Table: see text]

Prostate cancer treatment disparities during the COVID-19 pandemic, lessons from a multi-institutional collaborative

6542

Background: Minority communities have been disproportionately affected by COVID-19, however the impact of the pandemic on prostate cancer (PCa) treatment is unknown. To that end, we sought to determine the racial impact on PCa surgery during the first wave of the COVID-19 pandemic. Methods: After receiving institutional review board approval, the Pennsylvania Urologic Regional Collaborative (PURC) database was queried to evaluate practice patterns for Black and White patients with untreated non-metastatic PCa during the initial lockdown of the COVID-19 pandemic (March-May 2020) compared to prior (March-May 2019). PURC is a prospective collaborative, which includes private practice and academic institutions within both urban and rural settings including regional safety-net hospitals. As data entry was likely impacted by the pandemic, we limited our search to only practices that had data entered through June 1, 2020 (5 practice sites). We compared patient and disease characteristics by race using Fisher’s exact and Pearson’s chi-square to compare categorical variables and Wilcoxon rank sum to evaluate continuous covariates. Patients were stratified by risk factors for severe COVID-19 infection as described by the CDC. We determined the covariate-adjusted impact of year and race on surgery, using logistic regression models with a race*year interaction term. Results: 647 men with untreated non-metastatic PCa were identified, 269 during the pandemic and 378 from the year prior. During the pandemic, Black men were significantly less likely to undergo prostatectomy compared to White patients (1.3% v 25.9%;p < 0.001), despite similar COVID-19 risk-factors, biopsy Gleason grade group, and comparable surgery rates prior (17.7% vs. 19.1%;p = 0.75). White men had lower pre-biopsy PSA (7.2 vs. 8.8 vs. p = 0.04) and were older (24.4% vs. 38.2% < 60yr;p = 0.09). The regression model demonstrated an 94% decline in odds of surgery(OR = 0.06 95%CI 0.007-0.43;p = 0.006) for Black patients and increase odds of surgery for White patients (OR = 1.41 95%CI 0.89-2.21;p = 0.142), after adjusting for covariates. Changes in surgical volume varied by site (33% increase to complete shutdown), with sites that experienced the largest reduction in cancer surgery, caring for a greater proportion of Black patients. Conclusions: In a large multi-institutional regional collaborative, odds of PCa surgery declined only among Black patients during the initial wave of the COVID-19 pandemic. While localized prostate cancer does not require immediate treatment, the lessons from this study illuminate systemic inequities within healthcare, likely applicable across oncology. Public health efforts are needed to fully recognize the unintended consequence of diversion of cancer resources to the pandemic in order to develop balanced mitigation strategies as viral rates continue to fluctuate.

EA8185: Phase 2 study of bladder-sparing chemoradiation (chemoRT) with durvalumab in clinical stage III, node positive urothelial carcinoma (INSPIRE)—An ECOG-ACRIN and NRG Collaboration

TPS4590

Background: Patients [pts] withlymph node positive (LN+), non-metastatic bladder cancer (BC) have a better prognosis than those with metastatic (M1) disease. However, this population is under-represented in advanced bladder trials and ineligible for bladder-sparing trials. Therefore, there have been no larger prospective trials establishing the standard of care in LN+ BC. Given the promise of immunotherapy in advanced BC and potential synergy between immunotherapy and radiation, INSPIRE was designed to determine the role of concurrent and adjuvant durvalumab (durva) in this patient population when treated with induction chemotherapy (IC) followed by concurrent chemoRT. Methods: This is a randomized phase II study that is enrolling BC pts with stage III [N1-2 M0], pure or mixed urothelial cancer. Pts must have received ≥3 cycles of IC [either before or after registration, prior to randomization] without progression. LN+ is defined as radiologically LN ≥1.0 cm in short axis, with or without biopsy prior to IC. As long as pts do not progress on induction chemotherapy, they will be randomized to chemoRT+/- durva using 5 stratification factors (Simon Pocock minimization method) a) IC prior vs. post registration b) cisplatin vs non-cisplatin regimen during RT c) LN size d) response to IC e) extent of TURBT. Pts on the chemoRT+durva arm will get chemotherapy per physician choice + IMRT + 3 x doses of Q3wk durva for 6.5-8 wks, whereas those on the control arm will get chemoRT alone. The primary end point is clinical complete response [CR], defined as no radiologically measurable disease in the LNs and negative cystoscopy and bladder biopsy 8-10 weeks post-chemoRT +/- durva. Pts on the chemoRT + durva arm who have a CR or clinical benefit ( > T0 and ≤T2 in bladder per cystoscopy, biopsy + CR/PR/SD in LN by imaging) will get adjuvant Q4wk durva for 9 doses, while those on the chemoRT arm will undergo observation. Secondary end points include OS, PFS, bladder-intact event-free survival, rate of toxicity and salvage cystectomy. This study is designed to detect an improvement of 25% in clinical CR between both arms (37.5% to 62.5%). A total accrual of 114 pts (in order to enroll 92 evaluable pts) will provide 81% power to detect this difference using a Fisher’s exact test (assuming 10% drop out + anticipating that 20% chemotherapy-naïve pts will progress post IC). We are banking blood and primary tumor tissue pre- and post-chemoRT in both groups. The study was activated in August 2020 and accrual is ongoing. INSPIRE is the first prospective study designed for only LN+ BC and will define both short-term and long-term outcomes for bladder sparing in this patient population and has the potential to define a new treatment strategy for stage III BC. Clinical trial information: NCT04216290.

The use of 3D printed models on trainee and patient experience for partial nephrectomies

363

Background: 3D printing is a growing tool in surgical education due to the ability to visualize organs, tissue, and masses from multiple angles before operating on a patient. Previous studies using highly detailed and expensive 3D models costing between $1,000-250 per model have been shown to enhance patient and trainee comprehension of tumor characteristics, goals of surgery, and planned surgical procedure for partial nephrectomies. In our study we aim to use simpler and less expensive models in a greater range of patients receiving partial nephrectomies to determine the use of 3D models in patient, resident, and fellow education. Methods: 3D models of the effected kidney, mass, renal artery, and renal vein were created using preoperative imaging of undergoing partial nephrectomies at Thomas Jefferson University Hospital (TJUH) costing $35 per model. Residents and fellows filled out 3 surveys assessing their surgical plan and their confidence in the chosen plan at 3 time points: 1) Before seeing the model, 2) After seeing the model before surgery, and 3) After surgery. Ten patients filled out 2 surveys about their understanding of the kidney, their disease, the surgery they will undergo, and the risks involved with surgery before and after seeing the model. Results: Based on surveys to assess for surgical plan and confidence given to resident and fellow surgeons before and after seeing the 3D model, confidence significantly increased. Surveys given after surgery assessing anatomic and surgical comprehension found that resident and fellow surgeons rated the helpfulness of the models on their anatomical comprehension 7.6 out of 10 and the help of the models on their surgical confidence 7 out of 10. Patient understanding of their kidney, disease, and surgery significantly increased after seeing the 3D model, but the risks associated with surgery did not significantly increase. The extent that the model helped the patients learn about the kidney, their disease, the surgery, and the risks related to surgery were rated an average of 8.33, 9.67, 9.5, and 8.83 out of 10, respectively. Conclusions: Patient-specific 3D models for partial nephrectomies increase resident and fellow confidence in surgical approach and helped patients learn about their disease and feel comfortable going into surgery. Thus, it is important to continue to explore 3D models as an educational tool for both trainees and patients and potentially include 3D models as part of the standard of care. Further research could continue to explore the utility of 3D models as a pre-operative educational tool for both patients and trainees in other surgical fields.

Genomic analysis for active surveillance to predict upstaging after prostatectomy

258

Background: Active Surveillance (AS) of prostate cancers lowers morbidity and mortality with conservative management but requires vigilance to prevent disease progression. Understanding of disease aggression through genomic analysis has enhanced AS. About one third of prostatectomies reveal a Gleason upgrade to stage T3 or node positivity, and increased risk on a single genomic analysis increases the risk of progression and Gleason upgrade. More information is needed to compare these tests and determine their roles in academic and private practice settings. Methods: The Pennsylvania Urologic Regional Collaborative (PURC), funded by participating urology practices and the Partnership for Patient Care, a quality improvement initiative supported by the Health Care Improvement Foundation, Independence Blue Cross, and southeastern PA hospitals and health systems, database was analyzed with permission to find patients who received both AS and prostatectomy for treatment of prostate cancer. Patients were then selected who had genomic analysis performed on biopsy samples using analysis from Decipher Biopsy, Oncotype Dx, or Prolaris. Patients were sorted into genomic risk categories and biopsy pathology, prostatectomy pathology, and time to surgery was compared. Results: Thirty-nine patients met criteria for the study. Nineteen were considered to be very low risk based on genomic analysis, 11 were low risk, and nine were intermediate risk. Average time of progression from AS to prostatectomy was shorter with increased genomic risk: from 1.7 years for very low genomic risk individuals, to 1.3 for low risk, to 0.8 years for intermediate risk. All three groups had a significant decrease in Gleason Grade Group from biopsy to final pathology (p < 0.05). Five of the 19 patients (26%) in the very low risk group were upgraded to pT3 after prostatectomy, one (9%) of the low risk group was upgraded, and four of the 9 (44%) in the intermediate risk group were upgraded. Regardless of genomic risk, 14% of patients who had analysis performed with Oncotype Dx received a Gleason upgrade, compared to 67% of patients with Decipher Biopsy analysis and 43% of patients with Prolaris genomic analysis. Conclusions: Our pilot study indicates that while higher genomic risk categorization led to a more rapid progression to treatment, Gleason Grade Group decreased from biopsy to final pathology in each risk group, suggesting more time before progression to treatment may be warranted. Very low and low risk patients had less risk of Gleason upgrade compared to intermediate risk patients. While our numbers are low, the difference in Gleason upgrade based on genomic analysis provides an interesting exploratory analysis that requires further investigation. More analysis comparing the intricacies of the reporting methods is needed to elucidate the benefits and drawbacks for each genomic test available.

EA8185: Phase II study of bladder-sparing chemoradiation (chemoRT) with durvalumab in clinical stage III, node-positive urothelial carcinoma (INSPIRE), ECOG-ACRIN/nrg collaboration

TPS500

Background: Patients [pts] withlymph node positive (LN+), non-metastatic bladder cancer (BC) have a better prognosis than those with metastatic (M1) disease. However, this population is under-represented in advanced bladder trials and ineligible for bladder-sparing trials. Therefore, there have been no larger prospective trials establishing the standard of care in LN+ BC. Given the promise of immunotherapy in advanced BC and potential synergy between immunotherapy and radiation, INSPIRE was designed to determine the role of concurrent and adjuvant durvalumab (durva) in this patient population when treated with induction chemotherapy (IC) followed by concurrent chemoRT. Methods: This is a randomized phase II study that is enrolling BC pts with stage III (N1-2 M0), pure or mixed urothelial cancer. Pts must have received ≥3 cycles of IC [either before or after registration, prior to randomization] without progression. LN+ is defined as radiologically LN ≥1.0 cm in short axis, with or without biopsy prior to IC. As long as pts do not progress on induction chemotherapy, they will be randomized to chemoRT+/- durva using 5 stratification factors (Simon Pocock minimization method) a) IC prior vs. post registration b) cisplatin vs non-cisplatin regimen during RT c) LN size d) response to IC e) extent of TURBT. Pts on the chemoRT+durva arm will get chemotherapy per physician choice + IMRT + 3 x doses of Q3wk durva for 6.5-8 wks, whereas those on the control arm will get chemoRT alone. The primary end point is clinical complete response [CR], defined as no radiologically measurable disease in the LNs and negative cystoscopy and bladder biopsy 8-10 weeks post-chemoRT +/- durva. Pts on the chemoRT + durva arm who have a CR or clinical benefit (>T0 and ≤T2 in bladder per cystoscopy, biopsy + CR/PR/SD in LN by imaging) will get adjuvant Q4wk durva for 9 doses, while those on the chemoRT arm will undergo observation. Secondary end points include OS, PFS, bladder-intact event-free survival, rate of toxicity and salvage cystectomy. This study is designed to detect an improvement of 25% in clinical CR between both arms (37.5% to 62.5%). A total accrual of 114 pts (in order to enroll 92 evaluable pts) will provide 81% power to detect this difference using a Fisher’s exact test (assuming 10% drop out + anticipating that 20% chemotherapy-naïve pts will progress post IC). We are banking blood and primary tumor tissue pre- and post-chemoRT in both groups. The study was activated in August 2020 and accrual is ongoing. INSPIRE is the first prospective study designed for only LN+ BC and will define both short-term and long-term outcomes for bladder sparing in this patient population and has the potential to define a new treatment strategy for stage III BC. Clinical trial information: NCT04216290.

Phase Ib/II neoadjuvant (N-) pembrolizumab (P) and chemotherapy for locally advanced urothelial cancer (laUC): Final results from the cisplatin (C)- eligible cohort of HCRN GU14-188

5047

Background: Patients (pts) with laUC who are C-eligible for N- therapy may benefit from combination chemo-immunotherapy. Cohort 1 (C1) of the GU14-188 trial is a phase 1b/2 trial designed to assess the tolerability and efficacy of N- gemcitabine (G), C, and P in pts with laUC. The current standard of care is ddMVAC with a pathologic non-muscle invasive rate (PaIR, ≤pT1N0) of ~44%. Methods: Eligible pts for C1 were surgical candidates and C-eligible with cT2-4aN0M0 bladder UC. Enrollment followed a Simon 2-stage design for H0 of interval futility which was rejected at stage 1, and fully enrolled. Phase 1b (no DLT) /2 treatments were the same: P 200mg q3wks on day 8 x5 doses; with C (70mg/m2) day 1, and G (1000mg/m2) days 1 and 8 of a 21 day cycle (cy), for 4 cy; followed by radical cystectomy (RC). Minimum criteria for evaluation of safety: 1 dose of P, and for efficacy: 2 doses P and RC. The primary endpoint of PaIR was assessed at RC and designed for 86% power with 4% significance to detect a difference from 23 to 48%. Secondary endpoints include relapse free survival and overall survival. Results: 43 pts were enrolled to C1 with a median (mdn) age 64, 63% male, 51% > cT2. Mdn per-pt doses given (attempted) for: P:5(5), C:4(4), G:8(8). The PaIR was 61.1% (95%CI 0.45, 0.75), P0 (ypT0N0) rate of 44.4%, and did not correlate with baseline PD-L1 score. Downstage to PaIR occurred in 53% of cT2, and 74% of cT3/4. Mdn time to RC from last dose was 5.3wks. Seven were not included in the primary analysis: 4 (9.3%) without RC, 1 progressed, 1 lost to f/u during C1, 1 did not receive required protocol therapy. There was 1 death on post-RC day 9 due to mesenteric ischemia. Of 4 pts who did not have RC, 3 refused and 1 due to gr4 thrombocytopenic purpura; 4pts are alive and without recurrence at mdn f/u of 32mo. One pt with presumed gr3 MI during cy 4 had a negative inpt cardiac workup and completed therapy and RC without further AE. One gr4 hyponatremia and ten gr3 events did not preclude RC (2-each thromboembolism, elevated creatinine, hyponatremia;1-each: dehydration, emesis, neutropenic fever, infection). Gr 3/4 cytopenias occurred in 57% of pts. At mdn f/u of 34.2mo (3.9-47.4), the estimated 36mo RFS, OS, and DSS is 63%, 82%, and 87%, respectively. Conclusion: Neoadjuvant GC with P in laUC has manageable toxicity and has improved pathologic outcomes compared to historic controls. Durable long-term survival in those with- and without -RC is noteworthy in this advanced cohort. KEYNOTE 866, NCT03924856, is a Phase III study of GC with perioperative P. Clinical trial information: NCT02365766 .

Examining the real-world utility of immune checkpoint inhibitors in genitourinary oncology: A single-institution retrospective

e17112

Background: Immune Checkpoint Inhibitors (ICI) are increasingly utilized for genitourinary (GU) malignancies. However, data is lacking on the efficacy of these drugs in “real-world” populations - patients who do not fit the strict clinical trial criteria, but may still benefit from therapy. We performed a retrospective analysis of patients receiving ICI at a single tertiary-care institution, with special attention to clinical trial enrollment, adverse events, progression and survival. Methods: Patients receiving ICI for GU malignancies at Thomas Jefferson University Hospital from January 2017 to January 2019 were identified. Descriptive statistics of treatment and pathologies were performed. Progression-free survival (PFS) was calculated from start of ICI to documentation of progression or last follow-up. PFS and overall survival were assessed using Kaplan Meier log-rank test, stratified by trial enrollment. Results: 111 patients were included: 37 on ICI clinical trial, 70 received ICI “off-trial” and 4 received ICI in both settings. 11 patients (10%) underwent multiple courses of ICI throughout treatment. The number of patients initiating ICI increased annually; by 2018, the number of patients initiated on ICI “off-trial” exceeded those initiating ICI “on-trial” (79% vs 21%). Treated pathology included Urothelial Carcinoma (UC; 42%), Renal Cell Carcinoma (RCC; 28%), and Prostate Adenocarcinoma (PCa; 20%). “Off-trial” ICI was more often administered later in the disease course, compared to a more even distribution of “on-trial” ICI administration. Mean PFS and OS for both cohorts can be seen in Table. Conclusions: As seen in our single-institution referral center, the use of immune checkpoint inhibitors has significantly increased – and is now more commonly used off-trial than on-trial. As their use becomes more common, their efficacy in “off-trial” populations must be further investigated. [Table: see text]

Phase II neoadjuvant (N-) gemcitabine (G) and pembrolizumab (P) for locally advanced urothelial cancer (laUC): Interim results from the cisplatin (C)-ineligible cohort of GU14-188

5019

Background: Patients (pts) with laUC who are C-ineligible have inferior survival compared to counterparts who receive C based N-therapy and have a pathologic response at radical cystectomy (RC). Cohort 2 (C2) of the GU14-188 trial is designed to assess the tolerability and efficacy of N- G and P in laUC pts who are C-ineligible. Methods: Eligible pts for C2 were surgical candidates and C-ineligible with cT2-4aN0M0 bladder UC or mixed histology. Enrollment followed a Simon 2-stage design for H0 of interval futility which was rejected at stage 1, and fully enrolled. Pts were treated with N- G (1000mg/m2) on days 1, 8, and 15 of a 28 day cycle (cy) for a total of 3 cy, and overlapped with P 200mg every 3wks starting on cy 1 day 8 x 5 doses. Minimum criteria for evaluation of safety: 1 dose of P, and for efficacy: 2 doses P and RC. The primary endpoint of pathologic muscle invasive response rate (PaIR, ≤pT1N0) was assessed at RC and designed for 86% power, 4% significance to detect PaIR difference from 18 to 40%. Molecular subtyping is planned. Results: 37 pts were enrolled to C2 with a median (mdn) age of 72, 70% male, 55% > cT2. C-ineligibility was due to renal function (49%), hearing (30%), neuropathy (12%). Mdn per-pt doses given (intended) for P:5(5) and G:9(9). The PaIR was 51.6% (95%CI 0.35, 0.68), P0 (ypT0N0) rate of 45.2%, and neither correlated with baseline PD-L1 score. Downstage to PaIR occurred in 57% of pts with cT2, and 47% of > cT2. Mdn time to RC from last dose was 5.6wks. Six were not included in the primary analysis: 3 (8.1%) did not have RC due to progression (RFS censored), 2 did not receive required protocol therapy, and 1 withdrew consent. At mdn follow up of 10.8mo (4-24), the estimated 12mo RFS, OS, and DSS is 74.9%, 93.8%, and 100%, respectively. Treatment related AE included grade (gr) 3/4 neutropenia (24%), anemia (13%), and platelets (5%). There were no gr 4 non-heme AE, and of 14 (36%) pts with gr 3, 12 did not preclude RC. Of these, there were 4 gr 3 investigator assessed immune related adverse events (IAirAE) of pneumonitis (5%), colitis (3%), and AST elevation (3%). Though IAirAE improved, protocol therapy was discontinued in 3 pts: 2 did not have RC due to progression. Conclusion: N- G with P in C-ineligible pts with laUC is feasible with manageable toxicity, and has a pathologic downstage rate comparable to standard of care in the C-eligible population. G and P warrants further study with component contribution as a C- free N- option in laUC. Clinical trial information: NCT02365766 .

Concordance between MRI fusion versus TRUS prostate biopsy and final pathology at radical prostatectomy: Data from the PURC

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Background: Studies suggest that MRI-fusion guided biopsies are superior to the transrectal ultrasound guided (TRUS) technique. Herein, we present the Pennsylvania Urologic Regional Collaborative (PURC) experience with MRI fusion biopsy. We aimed to calculate concordance rates between TRUS prostate needle biopsy versus MRI fusion biopsy and final pathology at the time of radical prostatectomy within our cohort. Methods: Within PURC, a prospective quality improvement collaborative of urology practices in Pennsylvania and New Jersey, we identified all men who underwent a TRUS or MRI fusion prostate needle biopsy followed by radical prostatectomy for the treatment of prostate cancer from 2015 to 2018. We analyzed International Society of Urological Pathology Grade Group (GG) scoring and calculated the concordance and upgrading rates at the time of biopsy versus final pathology at radical prostatectomy. To assess for differences between our rates, we performed a test of equal proportions and Pearson's chi-squared test (significance = p<0.05). Results: We identified 1,437 men who underwent TRUS (n=1247) or MRI Fusion (n=196) biopsies followed by radical prostatectomy. Overall pathologic grading distribution at time of biopsy was: 35.8% (n=515) Grade Group (GG) 1, 28.5% (n=409) GG 2, 13.3% (n=191) GG 3, 11.5% (n=165) GG 4, and 10.9% (n=157) GG 5. Median number of cores at TRUS biopsy was 12 (IQR: 12,13). Median number of cores at MRI Fusion biopsy was 15 (IQR 13,18). Therefore, we inferred patients who underwent MRI Fusion biopsy also underwent standard TRUS biopsies at that time. On average, exact concordance rate between MRI Fusion biopsy and final pathology was 9.1% higher than concordance rate of TRUS biopsy (44.4% vs 35.3%, 95% CI: 1.6%-16.5%, p < 0.01). The overall rate of upgrading on final pathology for MRI fusion biopsies was 5.7% lower than for TRUS biopsies, but this was not statistically significant (35.2% vs 40.9%, 95% CI: 1.5-13.0%, p=0.06). Conclusions: MRI fusion biopsies demonstrated higher concordance rates with final pathology at the time of radical prostatectomy than TRUS prostate biopsies alone.

PET imaging urothelial bladder cancer: A novel approach

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Background: Urothelial bladder cancer (UBC) inflicts >80,000 new patients annually. Since treatment is stage-dependent, accurate staging is crucial. Conventional imaging and biopsy are often unreliable. A large number of PET tracers, developed to improve imaging, have limitations e.g. urinary excretion compromising their ability to assess the bladder lumen and invasive tumors. This study is to validate a hypothesis that high density VPAC receptors expression on UBC cell surface, can be targeted to PET image UBC, to determine loco-regional disease and metastatic lesions. Methods: Cu-64-TP3805 (4±10% mCi), with its high affinity (3.1 x 10−9M) for VPAC, was given IV to 19 UBC patients (44-80 yrs), scheduled for radical cystectomy. Those eligible for neoadjuvant chemotherapy were treated as such. Urine and blood samples were collected on the day of scan. Whole body PET/CT images acquired 60 to 90 min later and read by two physicians. Surgery was performed 1 to 4 weeks later. Imaging results were correlated with histology. Results: There were no adverse events. Urinary excretion of Cu-64-TP3805 was negligible. Blood clearance was biphasic (t ½ a = 22.3 ±2.7 min ~ 85% and t ½ β = 118.2 ± 4.9 min ~ 15%). VPAC PET bladder images were true positive (TP) in 11, true negative (TN) in 4, false positive (FP) in 1 and false negative (FN) in 3 patients with 79% sensitivity (95% CI 49%-95%), 80% specificity (95% CI 28%-100%), 92% PPV (95% CI 62%-100%), and 57% NPV (95% CI 18%-90%). Prostate images were TP in 8, TN in 6, and FP in 5 patients, with 100% sensitivity (95% CI 63%-100%), 55% specificity (95% CI 23%-83%), 62% PPV (95% CI 32%-86%), and 100% NPV (95% CI 54%-100%). The 5 FP images revealed HGPIN on re-analysis. For lymph nodes, images were TP in 1, TN in 14 and FN in 4 patients, with 25% sensitivity (95% CI 1%-81%), 100% specificity (95% CI 78%-100%), 100% PPV (95% CI 3%-100%), and 83% NPV (95% CI 59%-96%). In one patient, several lesions were seen in the spine and iliac crest. Biopsy was positive for metastasis. In smokers (N=12) there was diffused or focal tracer uptake in the lungs. In 7 non-smokers, 3 with CT depicted abnormality had tracer lung uptake and 4 did not. Conclusions: These first in human pilot study data depict Cu-64-TP3805 VPAC targeting to image UBC as worthy of further investigation.

The multidisciplinary clinic approach for bladder cancer treatment in the neoadjuvant therapy era

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Background: As urologic oncology becomes increasingly complex, the coordination of optimal and efficient care to patients can be challenging. Within our institution, we initiated a multidisciplinary center (MDC) comprised of urology, oncology and radiation oncology in 1996 to help meet these needs. The positive benefits of this approach have been demonstrated in other settings, but outcomes related to bladder cancer remain unclear, especially in the era of neoadjuvant (NA) therapy. Methods: Patients with localized or node positive muscle invasive bladder cancer (MIBC) without prior treatment were obtained from available multidisciplinary appointment records, dating from 7/5/17 to 9/25/19. Charts were then retrospectively reviewed to gather demographic data, treatment data, and pathological outcomes. Results: 66 patients fitting study criteria were identified. Average age was 71.3 years. 45 (68%) patients from this cohort were deemed to be radical cystectomy (RC) candidates, with 37 RC operations completed at time of record review. Of RC-eligible patients, 35/45 (77%) had received NA therapy, either in the form of neoadjuvant chemotherapy (NAC) and/or immunotherapy (NAI). 3 patients declined RC after receiving NAC. 15 patients underwent chemoradiation treatment (23%), while 7 (11%) underwent supportive care without definitive treatment. Downstaging at RC from MIBC (<=T1) was seen in 12/37 patients (32%), with a pT0 rate of 10% (4/37). Conclusions: The coordination of care in bladder cancer remains a challenge for patients and physicians alike. We believe by utilizing a multidisciplinary approach, efficiency and quality of care increases. National database studies have reported overall utilization of neoadjuvant chemotherapy over the past 10 years, with most recent rates ranging from 14.8-20.9%. Our utilization of neoadjuvant therapy is notably higher at 77%, which also includes early adaptation of NAI in patients deemed ineligible for neoadjuvant NAC. Further studies are needed to examine a contemporary control population outside the multidisciplinary setting, however the above outcomes provide a basis for the integration of care and its positive outcomes in quality improvement.

Defects in DNA repair genes and long-term survival in cisplatin-based neoadjuvant chemotherapy for muscle invasive bladder cancer (MIBC)

4536

Background: Although cisplatin-based neoadjuvant chemotherapy (NAC) has demonstrated an overall survival (OS) benefit in MIBC, only a subset of patients have pathologic complete response (pT0) at cystectomy. ATM, RB1 and FANCC mutations have shown correlation with pT0 to cisplatin-based NAC, as previously published. We now report updated OS and disease specific survival (DSS) from two phase II trials using these gene alterations as biomarkers. Methods: Patients with stage T2-T4 (N0 or N1) MIBC were enrolled in phase II trials of dose-dense NAC with MVAC (methotrexate, vinblastine, adriamycin, and cisplatin; NCT01031420) or GC (gemcitabine and cisplatin; NCT01611662). Patients were treated with NAC with plan for curative cystectomy. DNA from pretreatment tumor tissue was sequenced for coding exons of 287 cancer-related genes and analyzed for mutations. Survival in patients with one or more mutations in ATM, RB1, or FANCC genes was compared to those without mutations. Results: Of 58 pts treated, 38% (22/58 pts) had relevant mutations in the combined group of MVAC (13/34 pts) and GC (9/24 pts) trials. At a median follow-up of 56 months and minimum follow up of 16 months, patients with mutations had statistically significantly greater OS (p = 0.0043) and DSS (p = 0.0015). Median OS/DSS was not reached for patients with a mutation in any group. At 5 years post treatment, OS/DSS were greater in mutated vs non-mutated patients in all groups (see table). Conclusions: Long-term follow up reveals that previously reported improved responses to cisplatin-based NAC associated with mutations in ATM, RB1 and FANCC also confer a clinically meaningful and statistically significant survival benefit in these patients. These alterations may be useful as predictive biomarkers to allow clinicians to prioritize patients most likely to benefit from NAC prior to radical cystectomy. [Table: see text]

Incorporating mpMRI Biopsy data into established pre-RP nomograms: Potential impact of an increasingly common clinical scenario

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Background: Current pre-radical prostatectomy (RP) nomograms predicting lymph node involvement (LNI) are based on systematic 12-core prostate biopsies (PBx). With the introduction of mpMRI, cognitive or fusion biopsies have become prevalent, often in the absence of systematic cores. We examine the practical application of MR biopsy data using established pre-RP nomograms and the potential implications on RP intra-operative decision making. Methods: Utilizing a prospectively maintained single institution database, all patients who underwent MRI-based PBx prior to RP were identified. Each patient was assessed using the MSKCC Kattan nomogram and the Briganti nomogram using the following iterations: 1) Targeted [T] (targeted cores alone), 2) Targeted & Systematic [TS] and 3) Targeted Augmented [TA]. The TA iteration utilized targeted core data alone and assumed negative remaining systematic cores for a total 12 core. Nomogram outcomes, specifically risk of LNI, was compared across iterations. Clinically significant impact was defined as a change in risk above or below 2% (Δ2) or 5% (Δ5), based on current guidelines recommendations for lymph node dissection. Results: 69 men met inclusion criteria (6 targeted, 63 systematic + targeted PBx). In the 6 men with targeted only biopsies, using the Kattan and Briganti nomograms, Δ2 occurred in 1 patient (16.7%) and Δ5 in 1-2 patients (16.7-33.3%); in all, TA iteration LNI was lower than the T iteration. In the 58 patients with positive targeted biopsy cores, Δ2 and Δ5 were 8.62-32.76% and 25.86-37.93%, respectively. In the subset of 52 patients with both targeted and systematic biopsies, using their TS nomogram as an internal validation, the TA iteration was a better approximation of their TS outcomes than their T iteration in 48% (Kattan) and 67% (Briganti) of patients. Conclusions: mpMRI-based PBx results, and in particular those from targeted biopsy cores alone, yield significantly different results using established pre-RP nomograms. Therefore, future nomograms must better incorporate MRI biopsy data and provide guidelines on how to account for targeted cores. In the interim, augmenting targeted biopsy data may bridge the gap.

What is the clinical utility of next generation sequencing (NGS) in advanced urologic malignancies?

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Background: Widespread availability of NGS and an expanding repertoire of targeted therapies has garnered significant enthusiasm for the concept of NGS directed therapy. FoundationOne (Foundation Medicine, Cambridge, MA) is a validated comprehensive genomic profiling (CGP) assay intended to guide therapy decisions based upon tumor specific genetic variations. We reviewed our experience with FoundationOne testing in advanced genitourinary (GU) cancer and examined whether NGS effected therapy in a meaningful way. Methods: Retrospective review of patients with advanced GU cancer seen between 2/1/2013–8/13/2018 who had FoundationOne CGP testing. We then compared the duration patients were maintained on NGS directed therapy to the duration of each non-NGS therapy. Results: A total of 73 patients were identified with NGS testing for prostate (25, 34%), urothelial (30, 41%), and kidney (18, 25%) cancer. 11 (15%) of these patients had therapy directed against a genetic alteration indicated by NGS. Of the treated patients, 46% (5) had urothelial, 36% (4) had kidney, and 18% (2) had prostate cancer. The average duration that each non-NGS therapy was effective in patients with urothelial, kidney, and prostate cancer was 165, 417, and 382 days respectively. Duration of NGS directed therapy averaged 226, 367, and 278 days for urothelial, kidney, and prostate cancer. The range of the duration of response to NGS directed therapy for urothelial, kidney, and prostate cancer was 66-616 days, 106-467 days, and 28-528 days. Four (36%) patients treated with NGS directed therapy achieved a duration of response greater than the average duration of all other non-NGS directed therapy they had received (Table). Conclusions: A minority of patients received NGS directed therapy following NGS testing. Treated patients demonstrated varying responses with 4 patients experiencing a longer duration of response compared to non-NGS directed therapy. Our experience illustrates that NGS has a limited but evolving role in the management of advanced GU malignancies at this time while also demonstrating a benefit to a subset of patients. Future studies should focus on identifying which patients are most likely to benefit from this technology.

PARP-1 regulation of DNA repair factor availability

269

Background: PARP-1 holds major functions on chromatin, DNA damage repair and transcriptional regulation, both of which are relevant in the context of cancer. Previously, it was determined that PARP-1 ins involved in regulation of androgen receptor activity. Methods: Here, unbiased transcriptional profiling revealed the downstream transcriptional profile of PARP-1 enzymatic activity.Results: Further investigation of the PARP-1-regulated transcriptome and secondary strategies for assessing PARP-1 activity in patient tissues revealed that PARP-1 activity was unexpectedly enriched as a function of disease progression and was associated with poor outcome independent of DNA double-strand breaks, suggesting that enhanced PARP-1 activity may promote aggressive phenotypes. Mechanistic investigation revealed that active PARP-1 served to enhance E2F1 transcription factor activity, and specifically promoted E2F1-mediated induction of DNA repair factors involved in homologous recombination (HR). Conversely, PARP-1 inhibition reduced HR factor availability and thus acted to induce or enhance “BRCA-ness”. Conclusions: These observations bring new understanding of PARP-1 function in cancer and have significant ramifications on predicting PARP-1 inhibitor function in the clinical setting.

Questioning the status quo: Should Gleason 3+3=6 PCa be considered a “negative core” for pre-RP risk nomograms?

31

Background: Current pre-radical prostatectomy (RP) nomograms predicting RP pathology do not differentiate between Gleason 6 prostate cancer (Gl6 PCa) and clinically significant Gleason 7-10 PCa. As such, use of these nomograms can be problematic. We assess the impact of excluding Gl6 PCa on nomogram and RP outcomes. Methods: Utilizing a prospectively maintained database, all men who underwent prostate biopsy (PBx) prior to RP were identified. Each patient was assessed using the MSKCC Kattan and Briganti nomogram using the following iterations: 1) “Original” [ORIG] (all available core data) and 2) "Selective” [SEL] (only cores Gleason score ≥7). Nomogram outcomes (risk of LNI, ECE, SVI, and OCD), were compared across iterations and stratified based on pre-RP risk classification (3+3 [low], 3+4, 4+3, 8-10 [high]). Clinically significant impact on management [CSIM] was defined as a change in risk of LNI above or below 2% (Δ2) or 5% (Δ5), based on current guidelines recommendations for PLND. Nomogram outcomes were validated using RP pathology. Results: 1118 men met inclusion criteria. Using the Kattan nomogram, when compared to actual RP pathology, the SEL iteration was a better predictor of LNI, ECE and OCD than the ORIG iteration, but not SVI. Using the Briganti nomogram, the SEL iteration was a better predictor of LNI. As for CSIM, the greatest impact was on men with Gl7 PCa. In the 359 Gl 3+4 patients, Δ2 was 3.9-28.13% and Δ5 was 12.81-17.27%. In the 184 Gl 4+3 patients, Δ2 was 0% and Δ5 was 7.61-11.41%. In all cases, the change favored decreased need for PLND. Conclusions: As Gleason 3+3=6 PCa is increasingly being considered an insignificant prostate cancer, its inclusion in established pre-RP nomograms becomes problematic. We find that excluding Gl6 PCa cores from these nomograms can reduce the need to complete a PLND at the time of RP, and more importantly, may better reflect the true extent of cancer. [Table: see text]

Can post-operative prostate fossa radiation be omitted in patients with high-risk features using a genomic classifier?

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Background: At our institution, based upon the AUA/ASTRO guidelines, discussion of adjuvant radiation therapy (ART) for patients with adverse pathologic features (APF) (pT3/positive margins) occurs in a multidisciplinary setting. We had previously offered ART to approximately 50% of these patients. We describe our evaluation of Decipher genomic testing to select patients to offer observation following prostatectomy (RP). Methods: Since March 2014, patients at Thomas Jefferson University with APF and undetectable post-operative PSA underwent Decipher genomic testing. Collectively, we decided to offer observation with salvage radiation therapy (SRT) for patients with low or intermediate risk Decipher scores. The primary outcome of this analysis was biochemical progression free survival (bPFS) with failure defined as a PSA ≥0.1 ng/mL. Results: From March of 2014 through September of 2016, 47 patients met the above criteria. The median patient age was 64 and median follow up was 16 months. Median pre-treatment PSA was 6.0 ng/mL (2.94 to 22.7 ng/mL). With regard to pathologic stage: 19% had T2c, 68% had T3a, and 13% had T3b disease. Pathologic Gleason grouping was 6%, 49%, 34%, 6%, and 4% for groups 1-5, respectively. 51% of patients had positive margins, 36% had lymph-vascular space invasion, and 53% had perineural invasion. Four patients received ART and 1 patient was lost to follow up after his initial visit. Of the remaining 42 patients, 3 patients experienced biochemical failure at 8, 27, and 44 months. Conclusions: This is the first prospective report utilizing Decipher genomic testing to stratify men with undetectable PSA and adverse pathologic features into an observation cohort following RP. Despite the stringency of our definition of biochemical failure, our observed bPFS was 87% at 3 years. Historically, in an unselected population the 3 year bPFS was 90% in those receiving ART and 65% in those receiving SRT. While these initial findings are promising, longer follow up is warranted. Our findings demonstrate the utility of genomic classifiers in patient selection and provide a safe approach to reducing over treatment in the post RP setting.

Impact of decipher test on adjuvant and salvage treatments received following radical prostatectomy

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Background: Prostate cancer (PC) patients and providers have tremendous uncertainty as they decide on intervention with adjuvant or salvage radiation therapy (ART, SRT) after radical prostatectomy (RP). We prospectively evaluated the impact of Decipher test, a genomic classifier which predicts metastasis post-RP, on providers’ decision-making for ART and SRT. Methods: 150 men considering ART and 115 men considering SRT from 19 sites across the US were enrolled. Participating providers submitted a management recommendation prior to processing the Decipher test and again after receiving test results. We then followed patients for 12 months to assess actual treatment received and patient reported decisional conflict scale (DCS) and a validated survey on PC-related anxiety. Results: Pre-Decipher, observation was recommended for 89% of adjuvant men and 58% of salvage men. Post-Decipher, 17% of treatment recommendations changed in the adjuvant arm and 30% of recommendations changed in the salvage arm. Among adjuvant men, 78% maintained their recommended management 12 months after Decipher; 76% of salvage men maintained their recommended treatment after Decipher. Among 21 adjuvant men who intensified their treatment (observation to ART or ART to ART plus androgen deprivation therapy), 5 (24%) experienced biochemical recurrence with detectable PSA. In adjuvant men, PC-specific anxiety decreased differently among Decipher risk categories (p-value = 0.045), most notably among Decipher high risk men (9.07 [7.87, 10.26] pre-Decipher, 5.61 [5.35,5.88] 12 months post-Decipher). In salvage men, PC-specific anxiety decreased differently among those whose treatment were concordant (10.28 [8.1,12.47] pre-Decipher, 7.18 [6.82,7.54] 12 months post-Decipher) and those whose treatment were intensified (p-value = 0.01), and decreased differently among low-risk and high-risk Decipher patients (p = 0.04). Conclusions: Use of the Decipher test changed treatment decisions that was consistent with the eventual treatment received in three-fourths of adjuvant and salvage men after RP. Several men that pursued ART experienced PSA progression. PC-specific anxiety decreased in both adjuvant and salvage men. Clinical trial information: NCT02080689.

Decipher test’s impact on the postoperative management of prostate cancer

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Background: The Decipher Prostate Cancer Test provides risk stratification for prostate cancer aggressiveness and predicts the probability of metastasis after surgery. We aim to determine the impact on clinical decision-making Decipher risk designation has had at our institution since its implementation. Methods: A prospectively maintained single institution database was analyzed for patients who underwent prostate biopsy and prostatectomy between 2006-2017. Patients with pathologic T3 cancer, Gleason ≥3+4, or positive surgical margins were considered for the study. In cohort 1, patients’ Decipher scores were available prior to postoperative decision-making, in cohort 2 patients’ scores were not available. Postoperative management was then compared between cohorts to determine if presence of Decipher score influenced the rate of adjuvant and salvage radiation administered. The EMR was queried for the words “adjuvant”, “RT”, “salvage”, “SRT”, to record rates of radiation given to each patient. Chi Square and Mann Whitney test was used to compare rates between cohorts and Decipher risk categories. Results: 454 patients were included in the study with median (IQR) age of 62.0 (7.0) years. Mean time of follow-up was 2.0 years and 8.2 years in cohorts 1 and 2, respectively. In the cohort that received Decipher scores, rate of adjuvant radiation administered was significantly higher than in patients who did not receive a Decipher score (27.0% vs. 6.8%, p<0.001), and higher Decipher risk was associated with higher rate of adjuvant administration (9% vs 27.8% vs 35.4% for low, average and high risk, respectively; p<0.001). Rate of salvage radiation given was not significantly different between the cohorts (5.2% vs 4.0%; p=0.228). Conclusions: The Decipher Prostate Cancer Test provides valuable data regarding risk stratification of disease. As demonstrated here, the availability of Decipher scores has lead to a demonstrable effect in the postoperative management of prostate cancer.

A phase II trial of risk-adapted treatment for muscle invasive bladder cancer after neoadjuvant accelerated MVAC

TPS537

Background: Cisplatin-based neoadjuvant chemotherapy (NAC) followed by cystectomy (Cx) or chemoradiation (CRT) is the standard of care for urothelial carcinoma (UC) pts with muscle invasive bladder cancer (MIBC). Both Cx and CRT carry potential short and long-term toxicity and quality of life implications. Recent work has shown that mutations in DNA damage repair/response genes are predictive of pathologic downstaging after NAC at the time of Cx, with those pts achieving pT0 disease demonstrating excellent long-term survival (Van Allen et al. Cancer Discov. 2014; Plimack et al. Eur Urol. 2015; Liu et al. JAMA Oncol. 2016; Teo et al. CCR. 2017). Sparing pts Cx or CRT after NAC without compromising oncologic outcomes would improve quality of life and decrease morbidity. Methods: A phase II, parallel arm, multi-institutional clinical trial (NCT02710734) is being conducted to evaluate a risk-adapted approach to treatment of MIBC. Pts with cT2-T3N0M0 UC of the bladder, ECOG PS 0-1 and CrCl≥50 mL/min, undergo NAC with accelerated methotrexate, vinblastine, doxorubicin, and cisplatin. Simultaneously, the pre-NAC TURBT specimen is submitted for deep sequencing to identify variants in a panel of cancer-relevant genes (Caris Life Sciences, Phoenix, AZ). Those with an alteration in ATM, RB1, FANCC or ERCC2 and no clinical evidence of disease by restaging TUR and imaging post-NAC will begin a pre-defined active surveillance regimen that includes urinary cytological, cystoscopic, and radiographic evaluations. The remaining pts will undergo bladder-directed therapy at the discretion of the pt and clinician applying either intravesical therapy ( < cT2 post-NAC), CRT or Cx (≤cT2 post-NAC) or Cx (≥cT3 post-NAC). The primary objective is metastasis-free survival (MFS) at 2 years for all enrolled and evaluable pts. The trial has a non-inferiority design with a 14% margin between risk-adapted treatment (MFS = 78%) and standard-of-care (MFS = 64%) with a sample size of 70 pts, 82% power and a type I error of 0.045. Key secondary and translational objectives: assess the rate of UC recurrence in active surveillance pts; validate biomarkers of response to NAC; evaluate urinary biomarkers consistent with persistent UC. Clinical trial information: NCT02710734.

Immune response results from vesigenurtacel-l (HS-410) in combination with BCG from a randomized phase 2 trial in patients with non-muscle invasive bladder cancer (NMIBC)

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Background: Vesigenurtacel-L (HS-410) is a vaccine comprised of an allogeneic cell line, selected for high expression from a series of bladder tumor antigens, and transfected with gp96-Ig. Cell-secreted gp96-Ig delivers these cell-derived antigens to a recipient's own antigen presenting cells, activating CD8+ cytotoxic T cells. Here we present the secondary immune outcomes from a randomized Phase 2 trial with HS-410 in combination with BCG in NMIBC. Trial ID NCT02010203. Methods: 78 patients with intermediate- (n = 5) or high-risk (n = 73) NMIBC who are either BCG-naïve or recurrent, with or without carcinoma in situ (CIS), were enrolled 1:1:1 to one of two doses of HS-410 (either 106 or 107cells/dose) or placebo in combination with 6 weeks of induction BCG, followed by 6 more weeks of HS-410 in the induction phase. Maintenance treatment consisted of 3-weekly treatments at the following timepoints: 3 mo., 6 mo., 12 mo. Concurrently, 16 patients (1 int. risk, 15 high-risk) were enrolled in an open-label monotherapy HS-410 arm for patients who did not receive BCG. The primary endpoint was 1-year RFS. Secondary immune evaluations include ELISPOT, tumor IHC, tumor antigen profiling, flow cytometry, urine cytokine analysis, and T cell receptor sequencing. Results: HS-410 treatment was well tolerated; AE profiles were similar across the treatment arms. HS-410 antigen expression showed prominent overlap with patient tumors. IFNγ ELISPOT assay demonstrated a high baseline response to HS-410; responses to overlapping peptide pools of HS-410 derived antigens defined immune responders (doubling of IFNγ-secreting cells). IHC demonstrated that ~60% of NMIBC patient tumor biopsies were TIL negative at baseline (n = 84), but that only ~15% of tumor biopsies were TIL negative post treatment (n = 40). Thus, TIL status may be used to define a responder and non-responder population to HS-410. Conclusions: Vesigenurtacel-L is well-tolerated, and immunologic responses consistent with vaccine mechanism of action may correlate with efficacy and suggest future biomarkers. Vesigenurtacel-L warrants further investigation as a potential treatment for NMIBC. Clinical trial information: NCT02010203.

Immune response results of vesigenurtacel-l (HS-410) in combination with BCG from a randomized phase II trial in patients with non-muscle invasive bladder cancer (NMIBC)

319

Background: Vesigenurtacel-L (HS-410) is a vaccine comprised of an allogeneic cell line, selected for high expression from a series of bladder tumor antigens, and transfected with gp96-Ig. Cell-secreted gp96-Ig delivers these cell-derived antigens to a recipient's own antigen presenting cells, activating CD8+ cytotoxic T cells. Here we present the secondary immune outcomes from a randomized Phase 2 trial with HS-410 in combination with BCG in NMIBC. Trial ID NCT02010203. Methods: 78 patients with intermediate- (n=5) or high-risk (n=73) NMIBC who are either BCG-naïve or recurrent, with or without carcinoma in situ (CIS), were enrolled 1:1:1 to one of two doses of HS-410 (either 106 or 107cells/dose) or placebo in combination with 6 weeks of induction BCG, followed by 6 more weeks of HS-410 in the induction phase. Maintenance treatment consisted of 3-weekly treatments at the following timepoints: 3 mo., 6 mo., 12 mo. Concurrently, 16 patients (1 int. risk, 15 high-risk) were enrolled in an open-label monotherapy HS-410 arm for patients who did not receive BCG. The primary endpoint was 1-year RFS. Secondary immune evaluations include ELISPOT, tumor IHC, tumor antigen profiling, flow cytometry, urine cytokine analysis, and T cell receptor sequencing. Results: HS-410 treatment was well tolerated; AE profiles were similar across the treatment arms. HS-410 antigen expression showed prominent overlap with patient tumors. IFNγ ELISPOT assay demonstrated a high baseline response to HS-410; responses to overlapping peptide pools of HS-410 derived antigens defined immune responders (doubling of IFNγ-secreting cells). IHC demonstrated that ~60% of NMIBC patient tumor biopsies were TIL negative at baseline (n=84), but that only ~15% of tumor biopsies were TIL negative post treatment (n=40). Thus, TIL status may be further used to define a responder and non-responder population to HS-410. Conclusions: Vesigenurtacel-L is well-tolerated, and immunologic responses consistent with vaccine mechanism of action may correlate with efficacy and suggest future biomarkers. Vesigenurtacel-L warrants further investigation as a potential treatment for NMIBC. Clinical trial information: NCT02010203.

Effect of decipher test on adjuvant treatment decision-making among men with high-risk pathology at radical prostatectomy: Results from a multicenter prospective PRO-IMPACT study

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Background: The decision to provide adjuvant therapy to men with high risk pathology after radical prostatectomy (RP) is confounded by tremendous uncertainty. We prospectively evaluated the impact of the Decipher test, which predicts metastases after RP, on men and providers decision quality. Methods: 150 adjuvant pts were enrolled by 43 urologists from 19 practices. Pts with pathologic T3 stage or positive surgical margins (SM+) after RP were included. Participating physicians provided a treatment (Tx) recommendation before and after exposure to Decipher test results. Pts completed validated surveys on health-related quality of life, decisional conflict, and PCa-related anxiety. Results: Median patient age at RP was 64 years; 67% and 50% had pT3 and SM+ pathology, respectively. Decipher classified 46%, 22% and 32% of men as low-, intermediate- and high-risk, respectively. Pre-Decipher, observation was recommended for 89%. Post-Decipher, 18% (95% CI 12-25%) of Tx recommendations changed. Men’s Decisional Conflict Scale (DCS) scores decreased (indicating higher decision quality) after exposure to Decipher results (median DCS pre-Decipher 25 [IQR 8-44], median DCS post-Decipher 19 [IQR 2-30], p<0.001), with greatest decreases in the subdomains of decision uncertainty and decision support. Low-risk Decipher results experienced a trend toward decreased PCa-specific anxiety (p=0.13) and a significant reduction in fear of PCa recurrence (p=0.02). Physicians’ median DCS scores decreased from 32 [IQR 28-36] to 28 [IQR 12-42] (p<0.001). Decipher results were associated with the decision to pursue ART in an MVA analysis (OR 1.48; 95% CI 1.19-1.85, p<0.001). Conclusions: Observation is the predominantly prescribed management strategy for men with high risk features at RP. Knowledge of Decipher results was associated with Tx decision-making: men at low risk for metastasis had higher rates of observation recommendations and men at high risk had higher rates of ART recommendations. Decision quality was improved and PCa-specific anxiety was decreased for men exposed to Decipher results. Clinical trial information: NCT02080689.

Evaluating the effect of therapy duration on survival in patients with metastatic castration-resistant prostate cancer receiving radium-223

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Background: The use of radium-223 in patients with metastatic castration-resistant prostate cancer (mCRPC) improves overall survival (OS) and quality of life. Combination of radium-223 with second-generation anti-androgens has further improved OS; however, the optimal length of radium-223 treatment for maximal effect remains unknown. Methods: We reviewed 35 consecutive patients with mCRPC who received radium-223 from December 2012 to August 2015 at Thomas Jefferson University. Patients were divided into two groups: those who received full treatment of 6 injections (n = 18) versus those who received less than 6 injections (n = 17). Kaplan-Meier analysis of OS were tested for difference by treatment group using Log Rank test. Univariable association with survival outcomes was calculated with univariable Cox regression and Log Rank tests. Results: Mean age was 73 ± 10 years and Karnofsky performance status (KPS) ranged from 50-90 (median, 80). Median follow-up was 13.9 months. Eighteen patients were receiving concurrent second generation anti-androgens at the start of treatment. Median OS was 12 months for patients who received 6 injections and 6.48 months for patients who received less than 6 injections (p = 0.0045). The results of univariate Cox regression analysis revealed full treatment was associated with increased OS (p = 0.0013). On multivariate analysis accounting for KPS, full treatment was significantly associated with improved OS (p = 0.0028). Conclusions: In this retrospective, single-institution analysis, we demonstrated that full course completion of radium-223 was associated with improved OS in patients with mCRPC. These patients should be optimally supported during treatment to allow for therapy completion.

Effect of caloric restriction on the efficacy of radiation in both hormone-sensitive and hormone-resistant prostate cancers

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Background: Locally advanced prostate cancers (LAPC) are aggressive, have poor prognosis, and are associated with high recurrence rates and conversion to castrate resistance. The molecular underpinnings of LAPC are being investigated to identify novel therapeutics. Animal models have shown that caloric restriction (CR) can potentially prevent the initiation of prostate cancer. We propose that CR may be used as a novel therapeutic intervention to enhance outcomes of radiation treatment by altering the molecular profile of prostate tumors. Methods: To assess the effect of CR with radiation in vivo, 6 week old male nude mice were injected with LNCaP (hormone sensitive, N = 60) or PC3 (hormone refractory, N = 60) tumor cells. Once tumors were palpable, mice were randomized to be treated with one of 4 conditions: ad libitum (AL) diet, 8Gy of radiation (RT), 30% reduction in caloric intake (CR), or CR+RT. Results: After PC3 tumor injection, compared with AL, the mice had a 22% reduction in tumor size with radiation, 77% with CR (p < 0.01) and an 80% reduction with CR+RT (p < 0.01). After LNCaP tumor injection, compared with ad libitum, the mice had a 49% reduction in tumor size with CR and a 55% reduction with CR+RT (p < 0.01). Tissue evaluation of mice treated with CR or CR+RT from both the LNCaP and PC3 models revealed decreased proliferation via Ki-67 and increased apoptosis with cleaved caspase-3 levels. Furthermore we establish significant changes of the pro-inflammatory IGF-1R pathway hypothesized to play in intricate roll in prostate cancer; down regulation of serum IGF-1R, IRS-1, PI3K, pAKT, and IGF-1:IGF-BP3. Conclusions: For the first time, we have shown that the efficacy of radiation can be increased by decreasing calories by 30% in both hormone-sensitive and hormone-refractory prostate cancer models. Future clinical trials should consider the innovative use of CR to augment standard cancer therapy as it has the potential to change the biology of tumors and enhance the opportunity for clinical benefit.

Efficacy of early and delayed radiation in a prostatectomy cohort adjusted for genomic and clinical risk

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Background: In 3 published randomized trials, adjuvant radiation therapy (ART) for prostate cancer (PCa) resulted in improved progression free survival. However, the impact on metastases and overall survival is unclear. To date, there have been no published prospective trials examining the impact of salvage radiation therapy (SRT) in this disease state. Hence, we conducted a retrospective, nonrandomized comparative study of ART, SRT, or no radiation following radical prostatectomy (RP) for men with pT3 disease or positive margins (adverse pathologic features, APF). Methods: 422 PCa men treated at 4 institutions with RP and having APF were analyzed with a primary end point of clinical metastasis. ART (n = 111), early SRT (n = 70) and delayed SRT (n = 83) were defined by PSA levels of < 0.2, 0.2 to 0.5, and ≥ 0.5 ng/mL, respectively, prior to RT initiation. Remaining 157 men who did not receive additional therapy prior to metastatic onset formed the no RT arm. Clinical-genomic risk was assessed by CAPRA-S and Decipher. Cox multivariable (MVA) model was used to evaluate the impact of treatment on outcome. Results: During study follow-up, 37 men developed metastasis with a median follow-up of 8 years. Both CAPRA-S and Decipher had independent predictive value on MVA for metastatic outcome (both p < 0.05). On MVA adjusting for clinical-genomic risk, delayed SRT and no RT had an HR of 4.31 (95%CI, 1.20-15.47) and 5.42 (95% CI, 1.59-18.44) for metastasis compared to ART. No significance difference was observed between early SRT and ART (p = 0.28). Men with low to intermediate CAPRA-S and low Decipher have a low rate of metastatic events regardless of treatment selection. In contrast, men with high CAPRA-S and Decipher benefit from ART, however the cumulative incidence of metastasis remains high. Conclusions: The decision as to the timing and need for additional local therapy following RP is nuanced and requires providers and men to balance risks of morbidity with improved oncologic outcomes. This analysis provides the most robust and accurate quantification of risk for these men. Post-RP treatment can be safely avoided for men who are low risk by clinical-genomic risk, whereas those at high risk should favor enrollment in clinical trials.

Validation of a genomic classifier for prediction of metastasis following postoperative salvage radiation therapy

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Background: Management of patients with a postoperative rising prostate-specific antigen (PSA) level is complex. Additional local treatment such as salvage radiation therapy (SRT) may be sufficient for many patients but some may require concurrent systemic therapy in order to delay or prevent metastatic disease. As PSA recurrence on its own is a poor surrogate for metastatic disease we hypothesized that the Decipher genomic classifier (GC), a validated predictor of metastasis may be able to better distinguish those patients where additional therapy is beneficial from those where SRT on its own is likely sufficient. Methods: Genomic classifier (GC) scores were calculated from 170 prostate cancer patients, who received SRT at the Veteran Affairs Medical Center Durham, Thomas Jefferson University and Mayo Clinic, between 1990 and 2010. SRT was defined as administration of RT with Pre-RT PSA levels > 0.2 ng/ml. GC and CAPRA-S scores were compared using survival c-index, competing-risks and Cox regression analysis for the prediction of metastasis. Results: Survival c-index for predicting metastasis 5 years post SRT was 0.85 (95% CI: 0.73-0.88) for GC and 0.63 (95% CI: 0.49-0.77) for CAPRA-S. The cumulative incidence of metastasis at 5 years post-SRT was 2.7%, 8.4%, and 33.1% for low, average, and high GC scores (p < 0.001) and 16.9%, 2.3% and 17.2% for low, average and high CAPRA-S scores (p = 0.113). In univariable analysis only GC, extraprostatic extension, path GS and Pre-RT PSA were significant predictors of metastasis. In multivariable analyses with clinical risk factors or the CAPRA-S risk model, GC was the only independent predictor of metastasis with a HR of 1.63 (1.22-2.18, p < 0.001) for a 10% unit increase in risk score. Conclusions: In patients treated with postoperative SRT for PSA recurrence, GC is a powerful predictor of metastasis. Patients with low Decipher have excellent prognosis with SRT and may avoid concurrent hormonal therapy. Patients with high Decipher risk are at highest risk for metastatic disease and SRT failure and may benefit from intensified systemic therapy.

Phase I trial of weekly cabazitaxel with concurrent intensity-modulated radiation therapy (IMRT) and androgen deprivation therapy (ADT) for the treatment of high-risk prostate cancer (PCa)

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Background: Cabazitaxel (C) improves overall survival and has been approved in second line chemotherapy for patients (pts) with metastatic castrate resistant PCa. We hypothesized that C is a radiosensitizer and performed a phase I trial of weekly C with standard IMRT and ADT for pts with high risk localized PCa. Methods: Conventional “3 + 3” design. Pts with newly diagnosed high risk PCa defined as either Gleason score (GS) 8 – 10, or T3/T4 with GS 7, or PSA > 20 with GS 7 are eligible. Dose escalation occurred only after all the cohort pts completed weekly C ( 4 cohorts at the dose of 4, 6, 8 and 10 mg/m2) and the total planned dose IMRT. ADT was started two months prior to C and IMRT then continued on for a total of 24 months. Daily bicalutamide started within 1 day to 2 weeks prior to LHRH agonist therapy and stopped on the last day of IMRT for approximately 4 month duration. IMRT is delivered to a total dose of 75.6 Gy at 1.8 Gy daily fraction for 8.5 – 9 wks. The primary objective of this study was to determine the safe dose of the combination of weekly C with IMRT and ADT . Results: At present, 14 pts of mean age 62 yrs (range 53 – 82), T2 - T4; mean PSA 89 (range 4 – 253); and median GS 9 (GS 7 – 10) were enrolled and 10 pts completed the chemo-radiation therapy. Grade 3 dose-limiting toxicites in the first two pts at the 8 mg/m2 C dose level were diarrhea and elevated transaminase, thus the maximum tolerable dose (MTD) of C with IMRT was determined to be 6 mg/m2. An expansion cohort is ongoing. In this dose level, there were ≤ grade 2 toxicities only (diarrhea, hypophosphatemia and leukopenia). No long term toxicities are observed. Standardized measurement of health status and quality of life will be presented. Conclusions: Concurrent weekly C with current standard IMRT is feasible with no unexpected toxicity. In combination with IMRT and ADT, the MTD of weekly C is 6 mg/m2 in pts with newly diagnosed high risk PCa. Clinical trial information: NCT01420250.

Defects in DNA repair genes and sensitivity to cisplatin based neoadjuvant chemotherapy (NAC) for bladder cancer

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Background: Cisplatin based NAC prior to cystectomy is standard of care for MIBC, with 40-50% expected to respond with ≤pT1N0M0. Biomarkers predictive of response are lacking. Methods: MIBC pts who received 3 cycles of cisplatin based NAC on 1 of 2 prospective multicenter clinical trials were included. Pts treated with accelerated methotrexate, vinblastine, doxorubicin + cisplatin (AMVAC) provided the discovery set [n=34, 15/34 (44%) ≤pT1N0M0]. Pts treated with dose dense gemcitabine + cisplatin (DDGC) provided the validation set [n=24, 11/24 (46%) ≤pT1N0M0]. DNA from pre-treatment tumor tissue underwent sequencing for all coding exons of 287 cancer related genes and was analyzed for presence of base substitutions, indels, copy number alterations, and selected re-arrangements. The mean number of variants and variant status for each gene were correlated with response using two-sample t-test and Fisher’s exact tests. Variant data were used to create a classification tree to discriminate responders vs. non-responders in the AMVAC discovery cohort. The resulting decision rule was then tested in the independent DDGC validation set. Overall survival analysis was performed using Kaplan-Meier. Results: Pts with pT0 had significantly more alterations than those with residual tumor in both the AMVAC discovery (p=.024) and DDGC validation (p=0.018) set. In the AMVAC discovery set, alteration in ≥1 of the three DNA repair genes ATM, RB1 or FANCC predicted for ≤pT1N0M0 (p<0.001, 87% sensitivity, 100% specificity) and improved overall survival (OS) (p=0.007). This test remained predictive for ≤pT1N0M0 in the DDGC validation set (p=0.033), with a trend towards improved OS (p=0.07) at short median follow up of 14.3 mo. Conclusions: Alterations in ≥1 of ATM, RB1 and FANCC predict response to cisplatin based chemotherapy defined as ≤pT1N0M0 in both our AMVAC discovery and DDGC validation sets. We hypothesize that defects in these genes, which are important for maintenance of chromatin structure and DNA repair, confer sensitivity to DNA damaging chemotherapy and explain the accumulation of alterations seen among pts with pT0. External validation in collaboration with the cooperative groups is planned.

A genomic classifier to identify men with adverse pathology post radical prostatectomy who benefit from adjuvant radiation therapy

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Background: The optimal timing of postoperative radiotherapy following radical prostatectomy (post-RP RT) is unclear. We hypothesized that a genomic classifier (GC) would provide prognostic and predictive insight into the development of clinical metastases in men receiving post-RP RT and inform decision-making. Methods: GC scores were calculated from 188 patients with pT3 or margin positive PCa, who received post-RP RT at Thomas Jefferson University and Mayo Clinic, between 1990 and 2009. The primary endpoint was clinical metastasis. Prognostic accuracy of the models were tested using c-index and decision curve analysis. Cox regression tested the relationship between GC and metastasis. Results: The cumulative incidence of metastasis at 5 years post-RT was 0%, 9%, and 29% for low, average, and high GC scores, respectively (p=0.002). In multivariable analysis, GC and pre-RP PSA were independent predictors of metastasis (both p<0.01). Within the low GC score (<0.4), there were no differences in the cumulative incidence of metastasis comparing those who received adjuvant or salvage RT (p=0.79). However, for patients with higher GC scores (≥0.4) cumulative incidence of metastasis at 5-year was 6% vs. 23% for patients treated with adjuvant vs. salvage RT (p<0.01). Conclusions: In patients treated with post-RP RT, GC is prognostic for the development of clinical metastasis beyond routine clinical/pathologic features. Though preliminary, patients with low GC are best treated with salvage radiation, while those with high GC benefit from adjuvant therapy. These findings provide the first rationale selection of timing of post-RP RT.

Neoadjuvant accelerated methotrexate, vinblastine, doxorubicin, and cisplatin (AMVAC) in patients with high-grade upper-tract urothelial carcinoma

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Background: Improved safety and response rates of AMVAC over standard MVAC in patients (pts) with metastatic bladder cancer support study of neoadjuvant AMVAC for pts with muscle invasive bladder cancer (MIBC) and prenephroureterectomy (NU) for pts with high-grade upper-tract urothelial cancer (UTUC). We performed a phase II study of neoadjuvant AMVAC in MIBC and UTUC, and herein report the results of the UTUC exploratory subgroup. Methods: Pts with UTUC (ureter or renal pelvis) with high-grade UC on biopsy, or positive urine cytology and mass on cross sectional imaging, N0-N1, CrCl >=50, adequate hepatic and marrow function were eligible. Pts received 3 cycles of AMVAC (methotrexate 30 mg/m2, vinblastine 3 mg/m2, doxorubicin 30 mg/m2, cisplatin 70mg/m2) day 1, pegfilgrastim 6 mg day 2 or 3, every 2 weeks. NU, with lymph node dissection at surgeon discretion, was performed 4-8 weeks after last cycle. Exploratory endpoint was pathologic complete response (pCR) rate. Results: Accrual is complete with 10 evaluable UTUC pts enrolled at 2 institutions (FCCC, TJU) over 46.5 months. Median age 67 (range 49-83). Of 10 pts, 6 completed all 3 cycles of AMVAC. Four pts received < 3 cycles due to grade 3 acute kidney injury (1), pyelonephritis and grade 3 diverticulitis (1), flare of underlying hepatitis (1), grade 3 fatigue (1). Additional related grade 3 adverse events (AE) were anemia (1) and nausea/vomiting (1), no grade 4 or 5 AE. All pts underwent NU within 8 weeks of last chemotherapy, median 5.5 weeks. Median time from day 1 AMVAC to NU was 9 wks. 1/10 pts had a pCR, 4/10 patients were staged <pT1, 2/10 pT2, and 3/10 >pT3 or N+. An additional 21.5 months of enrollment were needed in this expansion cohort to accrue 10 pts with UTUC, compared to 44 MIBC pts in 25 mos. All pts completed study treatment as of July 2013. Conclusions: In this small sample, neoadjuvant AMVAC prior to NU was clinically active with manageable toxicity. With short duration from start of chemotherapy to NU, 3 neoadjuvant AMVAC cycles should be considered for further study for high-grade UTUC prior to NU in the cooperative group setting. Clinical trial information: NCT01031420.

Validation of a genomic classifier for predicting biochemical failure following postoperative radiation therapy in high-risk prostate cancer

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Background: Radiation therapy (RT) is commonly offered in the post radical prostatectomy (RP) setting, however response varies. We hypothesized that the genomic classifier ([GC] Decipher) score would predict biochemical failure (BF) and distant metastasis (DM) in men receiving post−RP RT. Methods: Under an institutional review board approved protocol, 223 men who underwent post−RP RT at the Kimmel Cancer Center of Thomas Jefferson University for pT3 or margin positive disease from 1990 to 2009 were identified. RNA was extracted from 143 patients with paraffin−embedded specimens and expression quantified from the highest Gleason grade tumor focus using a high−density oligonucleotide microarray. Excluding men who received neo−adjuvant therapy, 139 patients remained for GC calculation. Area under the receiver operating curve (AUC), decision curves, cumulative incidence accounting for competing risks, and multivariable Cox regression analyses were used to assess GC for predicting BF and DM after RT in comparison to nomograms. Results: The AUC of CAPRA-S was 0.67 (95% CI 0.58−0.77) and 0.65 (95% CI 0.44−0.86) for BF and DM, respectively. Integration of GC improved AUC to 0.75 (95% CI 0.66−0.84) and 0.77 (95% CI 0.64−0.91) for BF and DM, respectively. Cumulative incidence of BF at 8 years post-RT was 21%, 48%, and 81% for low (less than 0.4), intermediate (0.4 to 0.6), and high (more than 0.6) GC, respectively (p<0.00001). In multivariable analysis, patients who received RT early (pre−RT prostate-specific antigen [PSA] less than 1 ng/mL) had a BF benefit with a significantly reduced hazard ratio (HR) of 0.32 (95% CI 0.11−0.96, p<0.042). Patients with high GC had an HR of 14.73 for BF (95% CI 4.90−44.31, p<0.00001). Earlier PSA recurrence was observed in patients with high GC score that received salvage compared to adjuvant RT with median BF survival post-RT of 4.67 versus 8.78 years (p<0.04). This held true after adjusting for CAPRA-S score. Conclusions: This is the first validation of the GC in the post−RP RT setting. GC improved risk stratification above clinical classifiers. Patients with high GC received significant benefit from early RT intervention. For those patients with high pre-RT PSA and high GC, exploration of intensified therapy is warranted.

A phase II study of 99mTc-trofolastat (MIP-1404) SPECT/CT to identify and localize prostate cancer in high-risk patients undergoing radical prostatectomy (RP) and extended pelvic lymph node dissection (EPLND) compared to histopathology: An interim analysis

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Background: Technetium (Tc99m) trofolastat (USANC) is a novel urea-based small molecule SPECT radiotracer with utility in imaging overexpression of PSMA in prostate cancer (PCa). Unlike earlier agents targeting PSMA, this ligand is rapidly internalized and retained in tumors. We conducted an open-label, multicenter phase 2 study in the US and Europe (NCT01667536). An interim analysis was performed at approximately 50% accrual. Methods: Patients (pts) with confirmed adenocarcinoma of the prostate scheduled for RP with EPLND at high risk for disease outside of the prostate gland were eligible. High risk pts were ≥cT3 or Kattan nomogram score ≥130. Within 30 days of screening, pts required a bone scan and pelvic MRI. After enrollment, pts received trofolastat followed by whole-body planar and SPECT/CT imaging 3 to 6 hrs later. Pts then underwent RP with EPLND within 21 days. SPECT/CT images were evaluated centrally by 3 readers blinded to clinical information and compared to on-site pathology assessments using a common scoring template. The primary endpoint was the ability of trofolastat to detect PCa within the gland. Secondary endpoints included detection of extent and location within the gland, pelvic lymph nodes and comparative performance against MRI. Results: 84 pts were enrolled to date from 16 centers. Interim data is available for 54 pts. A majority (≥2/3) of SPECT/CT readers correctly identified the presence or absence of primary PCa in 51/54 (94%, 85-98 95% CI) patients including 2 true-negative cases treated with neoadjuvant enzalutamide. Sensitivity and specificity were 94% (84-98 95% CI) and 100% (34-100 95% CI) respectively. Conclusions: Based on the interim data available, trofolastat has accurately detected primary prostate carcinoma within the gland with high sensitivity and specificity in high-risk pts prior to surgery. Updated results, analyses of secondary endpoints, pelvic lymph nodes, and comparative performance vs. MRI from this ongoing study will be presented. Clinical trial information: NCT01667536. [Table: see text]

Impact of a novel decision counseling program on treatment knowledge, decisional conflict, and choice in men with early-stage, low-risk prostate cancer

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Background: Active surveillance (AS - serial follow-up PSA, exam, and biopsy) is an option for men with early stage, low risk prostate cancer (LRPca). While data show comparable survival for AS vs active treatment (AT - surgery or radiation), currently most men with LRPca undergo AT. A pilot Decision Counseling Program (DCP) to assist men in making an informed, shared LRPca treatment decision was implemented. Methods: Men with LRPca seen at the Jefferson Genitourinary Multidisciplinary Cancer Center (JGUMDCC) were consented. A nurse educator (NE) reviewed risks/benefits of AS and AT; had the participant identify factors influencing treatment decision making and specify decision factor weights; entered data into an online DCP; and generated a report of participant treatment preference and decision factors. The report was used by the participant and clinicians in shared treatment decision making. A follow-up survey was administered 30 days after the visit, with treatment status assessed. Change in treatment-related knowledge and decisional conflict were measured using baseline and 30-day survey data. Results: Baseline decision counseling preference of 16 participants: 4 - AS, 8 equal for AS and AT, 4 - AT. At 30 days, 12 participants initiated AS, 4 chose AT; participant mean treatment knowledge scores (8-point scale) increased (+1.13 points); decisional conflict subscale scores (strongly disagree = 1, strongly agree = 5) decreased (uncertain: -1.15, uninformed: -1.36, unclear: -1.12; and unsupported: -1.15). Conclusions: Decision counseling and shared decision making helped participants become better informed about treatment choices and reduced uncertainty in treatment decision making. The combined intervention resulted in most participants choosing AS. Ongoing study recruitment, data collection, and analyses are planned.

A pilot phase II study of digoxin in patients with recurrent prostate cancer as evident by a rising PSA

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Background: Hypoxia-inducible factor 1α (HIF-1α) is a novel cancer drug target and inhibitors of hypoxia-response pathway are being developed. Digoxin and other cardiac glycosides were found to inhibit prostate cancer (PCa) growth via the inhibition of HIF-1α synthesis in mouse model. Epidemiologic data showed that use of digoxin in men was associated with a significant lower risk of development of PCa. We hypothesized that therapeutic dose of digoxin could inhibit human PCa growth and disease progression. Methods: Open label, non-placebo pilot study. Non-metastatic, biochemically relapsed PCa patients (pts) with prostate specific antigen doubling time (PSADT) of 3 -24 months and no hormonal therapy within the past 6 months were enrolled. All pts had testosterone > 50 ng/dL at baseline. Digoxin was taken daily with dose titration to therapeutic level (0.8 – 2 mg/dl) and pts had routine follow-up that include cardiac monitoring with EKG. The primary endpoint was to evaluate the proportion of patients at 6 month post-treatment that had a PSADT > 200% from the baseline. Results: Fifteen pts were enrolled into the study with 13 pts finishing the planned 6 months of treatment. Twenty percent (3/15) of the pts had PSA decrease >25% from baseline. At 6 months, 7 of 15 (47%) pts had PSADT > 200% of the baseline PSADT and were continued on study for an additional 24 weeks of treatment. Mean duration of digoxin treatment was 34.5 weeks. Digoxin was well tolerated with possible relation of one grade 3 back pain and one grade 2 hyperglycemia. No pts came off study due to cardiac reasons. Pre-and post-treatment PSA kinetics, vascular endothelial growth factors and other cytokines levels are being determined. Conclusions: Digoxin was well tolerated and showed a prolongation in the PSDAT in 47% of the patients. Digoxin may have biologic activity in men with androgen-dependent PCa but further controlled studies are required to confirm the results. Clinical trial information: NCT01162135.