Candidate surrogate endpoints in advanced prostate cancer: Aggregate meta-analysis of 143 randomized trials

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Background: The Intermediate Clinical Endpoints (ICEs) in Cancer of the Prostate (ICECaP) working group identified metastasis-free survival as a valid surrogate endpoint for overall survival (OS) for patients with localized prostate cancer. No comparably validated surrogate endpoints for OS exist in advanced prostate cancer. Methods: In this meta-analysis, PubMed was searched for trials in advanced prostate cancer, defined as node positive (N1M0), metastatic castration-sensitive (mCSPC), non-metastatic (M0CRPC), or metastatic castration-resistant prostate cancer (mCRPC). Eligible randomized trials were required to report OS and ≥1 intermediate clinical endpoint (ICE). ICEs included biochemical-failure (BF), clinical failure (CF), BF-free survival (BFS), progression-free survival (PFS), radiographic PFS (radiographic +/- other study defined endpoints). Candidacy for surrogacy was assessed using the second condition of the meta-analytic approach, correlation of the treatment effect of the ICE and OS, using R2 weighted by the inverse variance of the log ICE hazard ratio and defined as an R2 > 0.70. Results: A total of 143 randomized trials (n = 75,601 patients) were included. No candidate endpoints met criteria for surrogacy; R2 BF (n = 28,922) 0.42 (95%CI 0.18-0.64), BFS (n = 25,741) 0.57 (95%CI 0.37-0.73), CF (n = 22,616) 0.31 (95%CI 0.0075-0.56), PFS (n = 52,639) 0.50 (95%CI 0.35-0.63), and radiographic PFS (n = 52,548) 0.50 (95%CI 0.35-0.63). Within preplanned subgroups by castration sensitive or resistant disease, or by treatment type, neither BFS nor PFS met criteria for surrogacy. When assessing radiographically-defined progression (exclusive or with clinical progression), PFS for the overall group and by castration status did not meet criteria for surrogacy. Sensitivity analyses demonstrated that candidacy for surrogacy of all endpoints tested did not change over time. Conclusions: Our aggregate screening method for surrogate endpoints in advanced prostate cancer demonstrated commonly used clinical endpoints are not valid surrogate endpoints for OS, and further composite endpoint construction is necessary.

Characterization of fungal mycobiome in bladder cancer

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Background: Bacterial dysbiosis accompanies carcinogenesis in malignancies such as colon, breast and pancreatic cancer. However, the role of fungal mycobiome has not been evaluated in bladder cancer. With the sexual dimorphism that exists within bladder cancer (Bca) prevalence and survival, our study aims to characterize fungal mycobiome composition in Bca. Methods: This is a single site, non-randomized, prospective study of patients with the diagnosis of muscle invasive bladder cancer (MIBC) undergoing cystectomy from September 2020 to May 2021. Stool samples were collected during surgery using aseptic technique. We utilized the ITS1 region from DNA sample extracts, which was amplified in triplicate using primers with high specificity for ascomycete fungi (fluorescently-labeled forward primer ITS1F (CTTGGTCATTTAGAGGAAGTAA) and unlabeled reverse primer ITS2 (GCTGCGTTCTTCATCGATGC). Fungal PCR products were separated on the SCE 9610 capillary DNA sequencer (Spectrumedix LLC, State College, PA) using GenoSpectrum software to convert fluorescent output into electropherograms. Hierarchical clustering by Bray-Curtis distance was performed using hclust2. Mean normalized abundance for each amplicon was calculated from the three PCR replicates of each sample, excluding means below 1%. Results: A total of 29 patients (17 males and 12 females) were enrolled. The median (IQR) age was 74 yo (63-77), males, and 68.5 yo (58-78), females. Per figure 1, Saccharomycecales dominated the fungal community at order level with mean relative abundance of 36.35% females, and 21.20%, males. (Figure 1D) Tremellales was the second most notable order, composing 8.22% and 5.13% of male and female samples. There were no differences seen in alpha and beta diversity (Figure 1C) (Figure 1A, C), notable differences were seen across orders. The greatest difference between sexes in LDA( M:F) were noted in Saccharomycecales (log change -4.686, p=0.001/ padj= 0.01), Tremellales (log change 5.119, p=0.001/padj= 0.01), and Sporidiobolales (log change 4.839, p=0.001 padj= 0.03). (Figure 1B). Female bladder cancer patients demonstrating an increase abundance of Saccharomycecale. When assessing differences in fungal composition in patients with history of neoadjuvant therapy( NAC) (receipt vs none), patients with history of NAC exhibited a 3.48 increase in Saccharomycecale (padj= 0.015 ), 4.81 increase Tremalles (padj= 0.009) and 4.37 increase Pleosporales(padj= 0.009) . Conclusions: Mycobiome is an integral part of gut microbiota, with fungal elements relatively poorly studied. Nevertheless, the association between fungal dysbiosis and carcinogenesis across multiple cancers exists. Our study is the first to characterize fungal profile in bladder cancer patients, stratified by sex and receipt of NAC, with results highlighting key fungal players: Saccharomycecale, Tremallales, Pleosoporales.

Characterization and functional analysis of microbiome in bladder cancer

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Background: The role of microbiome in genitourinary cancer is an emerging field, with evidence implicating the important role of microbiome as causative factors or cofactors in tumorigenesis and drug metabolism. Our study aims to characterize healthy and bladder cancer enterotypes in the gut and identify functional alterations through the use of metagenomics data. Methods: After prospective collection of 29 rectal swab samples of bladder cancer (BCa) patients undergoing cystectomy, and 32 healthy volunteers, we perform 16S rRNA amplicon sequencing on 61 samples (29 with bladder cancer, 32 without cancer). Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) was applied to infer functional categories associated with taxonomic composition. The p values were adjusted using the false discovery rate. The a- and b-diversity analyses were performed using QIIME. The Mann-Whitney U test was employed to evaluate the statistical significance of b-diversity distances within and between groups of interest. Results: Across all the bladder cancer stool samples, estimation of relative abundance revealed of the five most dominant bacterial populations was Bacteroidales ( 46.21%), Clostridiales ( 32.29%), Burkholderiales (9.07%), Erysipelotrichales (3.20%) and Lactobacillales ( 2.20%). In contrast, healthy controls exhibited an increased relative abundance of Enterobacteriales ( 10.75% vs 0.52%) and Pseudomonadales (8.33% vs 0.18%) as compared to tumor samples. The microbial diversity differences between Bca and normal samples showed no differences across alpha diversity metrics (Shannon diversity p>0.05) as compared to normal tissue. However, there was significant difference in clustering of organisms as determined by principal coordinate analysis ( PCoA) ordination of unweighted UniFrac Distances, (p=0.002). Furthermore, upon stratification of patients on smoking status (all healthy=nonsmokers), clustering persisted, albeit non smokers with bladder cancer displayed an intermediate across PCoA. Bca samples exhibited higher LDA score Campylobacterales (log change 8.0, p<0.001, padj <0.001) ,Fusobacteriales (log change 6.11, p<0.001/ padj<0.01), Epysipelotrichales (log 2.55, p<0.001/ padj <0.001 ), Actinomycetales (log change 1.86, p=0.001/ padj<0.001), Verrucomicrobiales (log change 1.78, p=0.017/padj=0.031) and Enterobacteriales (log change -1.54,p=0.017/ padj= 0.132). Conclusions: In conclusion, our study provides preliminary evidence that the GI microbiota is different in bladder cancer patients. Collectively, our study highlights distinct microbial overexpression of Campylobacter and Fusobacterium in Bca cohort not previously reported, both implicated in tumorigenesis, and could serve as a target that could be modulated to enhance treatment response.

Possible Bioenergetic Biomarker for Chronic Cancer-Related Fatigue

BACKGROUND

Cancer-related fatigue is a highly prevalent, debilitating, and persistent symptom experienced by patients receiving cancer treatments. Up to 71% of men with prostate cancer receiving radiation therapy experience acute and persistent CRF. There is neither an effective therapy nor a diagnostic biomarker for cancer-related fatigue. This pilot study aimed to discover potential biomarkers associated with chronic cancer-related fatigue in men with prostate cancer receiving radiation therapy.

METHODS

We used a longitudinal repeated-measures research design. Twenty men with prostate cancer undergoing radiation therapy completed all study visits. Cancer-related fatigue was evaluated by a well-established and validated questionnaire, the Patient-Reported Outcomes Measurement Information System-Fatigue (PROMIS-F) Short Form. In addition, peripheral blood mononuclear cells (PBMC) were harvested to quantify ribonucleic acid (RNA) gene expression of mitochondria-related genes. Data were collected before, during, on completion, and 24 months postradiation therapy and analyzed using paired t-tests and repeated measures analysis of variance.

RESULTS

The mean of the PROMIS-F T-score was significantly increased over time in patients with prostate cancer, remaining elevated at 24 months post-radiation therapy compared to baseline. A significant downregulated BC1 ubiquinol-cytochrome c reductase synthesis-like (BCS1L) was observed over time during radiation therapy and at 24 months postradiation therapy. An increased PROMIS-F score was trended with downregulated BCS1L in patients 24 months after completing radiation therapy.

DISCUSSION

This is the first evidence to describe altered messenger RNA for BCS1L in chronic cancer-related fatigue using the PROMIS-F measure with men receiving radiation therapy for prostate cancer.

CONCLUSION

Our results suggest that PBMC messenger RNA for BCS1L is a potential biomarker and therapeutic target for radiation therapy-induced chronic cancer-related fatigue in this clinical population.

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

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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 .

Comorbidity burden in prostate cancer patients by ESRD status

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Background: The co-occurrence of cancer and end-stage-renal disease (ESRD) may pose significant challenge in the management of both diseases. Further complicating clinical decisions is our limited understanding of the comorbidity burden (CB), which also affects their outcomes to a considerable extent. The purpose of this study is to characterize the CB in prostate cancer patients, with and without ESRD. Methods: Using SEER-Medicare database between years 2000-2016, we retrieved sociodemographic variables, including age (40-54, 55-64, 65-74, and 75+), race (African American vs. all others), marital status (married/partnered vs. all others), residence in a census tract with poverty rate > 20%, and dual Medicare-Medicaid enrollment status; chronic conditions identified in the year of cancer diagnosis; and ESRD status preceding prostate cancer diagnosis. We limited our study population to cancer patients enrolled in Medicare at the time of cancer diagnosis, and were receiving their care through the fee-for-service system. In this descriptive analysis, we compared the prevalence of these conditions between prostate cancer patients by ESRD status. Results: Our study population included 2,046 ESRD and 302,136 non-ESRD men diagnosed with incident prostate cancer during the study period. Compared to non-ESRD patients, a disproportionately higher percentage of ESRD patients were in the 40-54 and 55-64 age groups compared to non-ESRD (11.0 vs 0.95% and 32.2% vs. 8.51%, respectively). Similarly, the percentage of prostate cancer patients who were African American was 44.1% among ESRD patients, compared with 13.6% in their non-ESRD counterparts. With regard to comorbidities, several conditions were significantly higher in ESRD than non-ESRD patients, including: anemia (65.4% vs. 15.3%), congestive heart failure (31.1% vs. 8.9%), ischemic heart disease (38.9% vs. 25.2%), diabetes (40.7% vs. 17.0%), hypertension (68.0% vs. 42.6%), hypothyroidism (4.6% vs. 2.9%), hyperlipidemia (43.1% vs. 35.1%), and stroke (3.7% vs. 2.5%). Conclusions: Compared to their non-ESRD counterparts, ESRD patients present with high CB, severely compromising their physiologic reserve and tolerance for various cancer treatment modalities, and affecting outcomes. Future studies should compare the prevalence of specific combinations of conditions constituting multimorbidity between ESRD and non-ESRD patients, and identify multimorbidity profiles associated with a lower likelihood to receive standard treatment. Such detailed analysis will be foundational to clinical management and outcome studies.

Emerging clinical phenotype of bone metastatic urothelial cancer (mUC): Association of early osseous metastases (EOM) and outcomes

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Background: Outcomes of patients (pts) with mUC with EOM have not thoroughly been described in the age of immuno-oncology. We hypothesized that EOM is associated with worse outcomes when compared to pts with non-osseous metastases (NOM). Methods: We used a multi-institutional database of pts with mUC who received systemic treatment (trt) between March 2005 and August 2019, to assess survival and palliative outcomes of pts with EOM vs NOM at the time of metastatic diagnosis (met dx). Wilcoxon rank-sum and chi-square tests were performed. Survival was estimated by Kaplan-Meier method, Cox regression analysis was performed. Results: We identified 270 pts, 72% men, mean age 67 ± 11 years, 28% never smokers. At met dx, 27% (n = 72) had ≥ 1 EOM; these pts were more likely to have de novo metastases vs. those with recurrent metastases (42% vs 19%, p < 0.001). Pts with EOM were more likely to have a change or stop in 1st line trt due to clinical progression (30.6% vs 15.7%, p = 0.006), and received fewer total lines of systemic trt, median of 1.0 (1.0-5.0) vs. 2.0 (1.0-8.0), p = 0.05. Pts with EOM had shorter median overall survival (OS) vs. those with NOM, (6.1 vs 13.7 months, p < .0001), HR = 2.79 (95% CI:1.95-3.97, p < .0001). Median OS was shorter for pts with EOM who received 1st line immune checkpoint inhibitor (n = 14) vs platinum-based chemotherapy (n = 43), (1.6 vs 9.1 months, p = 0.003). Pts with EOM received higher opioid analgesic doses at the first and last oncology outpatient visits compared to pts with NOM with mean morphine milligram equivalent (MME) dose of 60 ± 91 vs 28 ± 65 at first visit, p = 0.004, and 171 ± 214 vs. 94 ± 229 at last visit, p < 0.001. Conclusions: The presence of EOM in mUC is associated with worse outcomes vs. pts with NOM. Pts with EOM may benefit from 1st line platinum-based chemotherapy vs. checkpoint immunotherapy. Furthermore, pts with EOM experience more pain than pts with NOM and may benefit from early engagement with palliative care. Pts with EOM represent a population with a highly unmet need for systemic, targeted and/or radiation interventions. Molecular subtypes may further define these pts and analysis is planned. We encourage ongoing clinical trials to report outcomes in pts with EOM. A consensus on reporting of non-measurable disease is also needed. [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

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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 .

Prostate cancer outcomes by ESRD status

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Background: Persons with end-stage renal disease (ESRD) comprise a vulnerable subgroup of the population. Yet, rarely have studies on cancer disparities accounted for ESRD status. We sought to compare prostate cancer stage at diagnosis, treatment, and outcomes among men with and without ESRD. Methods: Utilizing SEER-Medicare database between years 2000-2016, we retrieved sociodemographic variables, including age (40-54, 55-64, 65-74, and 75+), race (African American vs. all others), marital status (married/partnered vs. all others), residence in a census tract with poverty rate > 20%; cancer stage at diagnosis (local, regional, distant, and unknown); treatment (surgery and radiation therapy); and overall and cancer specific survival (OS and CSS) from the SEER, and ESRD status preceding prostate cancer diagnosis from the Medicare portion of the file. In addition to descriptive analysis, multivariable survival analysis was utilized to evaluate the association of ESRD status with OS and CSS after adjusting for patient covariates. Results: Our study population included 2,922 ESRD and 600,848 non-ESRD men diagnosed with incident prostate cancer during the study period. A disproportionately higher percentage of ESRD patients were in the 40-54 age group compared to non-ESRD (9.7 vs 3.6%). Similarly, the percentage of prostate cancer patients who were African American was 41.5% among ESRD patients, compared with 14.4% in their non-ESRD counterparts. In addition, more ESRD than non-ESRD patients lived in census tracts with poverty rates greater than 20% (31.2% vs. 18.0%). With regard to stage, 10.6% of ESRD patients but only 4.5% of non-ESRD patients were diagnosed with distant-stage disease; and while only 24.8% of ESRD patients underwent surgery, 36.9% of non-ESRD patients did so. The rate of radiation therapy was similar across the two groups. Multivariable survival models showed that, adjusting for patient covariates, ESRD status was associated with unfavorable OS and CSS (adjusted hazard ratio (AHR): 4.00 (95% confidence interval: 3.82, 4.18), and AHR: 1.54 (1.37, 1.73), respectively). Median follow up was 3.35 and 7.13 years between the ESRD and non-ESRD cohorts. Conclusions: ESRD status in prostate cancer patients is associated with marked sociodemographic and economic disparities. Compared to their non-ESRD counterparts, more ESRD patients are diagnosed with advanced-stage disease, are less likely to undergo surgery, and experience shorter overall and cancer-specific survival. Future studies should be directed to gain insight into factors contributing to unfavorable cancer-specific outcomes.

Association of early bone metastases and outcomes of the bone predominant metastatic urothelial carcinoma (BP mUC) phenotype

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Background: Prior analyses demonstrated worse outcomes with the BP mUC clinical phenotype. UC molecular subtypes that may correlate with the BP phenotype have been defined, however molecular subtyping is not a readily available standard practice. We hypothesized that BP mUC has worse prognosis vs. non-BP (NBP) mUC and evaluated patient (pt) characteristics associated with the mUC subtype, responses and outcomes. Methods: We searched the electronic medical record (EMR) to identify pts with mUC who received systemic therapy in the metastatic setting. Demographic, clinicopathologic, treatment (trt), response, progression-free survival (PFS), overall survival (OS ) from start of first line trt. Imaging was reviewed to identify NBP or BP disease. Logistic regression, Cox proportional-hazards and Kaplan-Meier analyses were performed. Results: 149 mUC pts were identified (64% male, 68% smokers ), median age at 1st line trt was 68 years. 70% had de-novo mets, 46% to lung and 27% to liver. 22% of pts were BP, of these, 36% were de-novo metastatic. In non- de-novo metastatic pts (70% of pts), first progression of disease to bone was associated with development of the BP phenotype (OR = 30.46, 95% CI 6.37 to 145.61; p < 0.0001). BP pts had higher rate of death (HR = 2.28, 95% CI 1.45 to 3.58, p = 0.0004), shorter PFS from 1st line trt, (11.7 vs 14.9 weeks, p = 0.032) as well as shorter OS from 1st line trt (24.6 vs 56.6 weeks, p = 0.002) compared to NBP pts. There was no difference in PFS between BP and NBP groups for pts treated with 1st line platinum-based chemotherapy (11.8 vs 18.3 weeks, p = 0.091) or for BP pts treated with 1st line immunotherapy vs platinum-based chemotherapy (11.71 vs 11.86 weeks, p = 0.135). Conclusions: Early bone metastases are associated with the development of the BP metastatic phenotype. BP pts have worse PFS and OS from 1st line trt compared to NBP pts. PFS remains poor when BP pts are treated with either platinum-based chemotherapy or immunotherapy in the first line setting. Imaging to determine the presence of bone metastases may routinely be pursued and careful attention paid on follow up imaging. Clinical trials and prospective registries focusing on efficacy endpoints for BP mUC are needed.

Patient reported outcomes in NRG Oncology/RTOG 0938, evaluating two ultrahypofractionated regimens (UHR) for prostate cancer (CaP)

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Background: The considerable interest in short UHR 5-12 fractions(fr) in management of CaP is based on potential radiobiological advantages, patient convenience & resource allocation benefits. Prior to comparison with standard RT regimens (SRTR), a study was undertaken whose primary objective was to demonstrate that 1-year health-related quality of life (HRQOL) for at least one UHR arm was not significantly lower than baseline as measured by the Bowel & Urinary domains EPIC instrument(EPIC B&U). Secondary objectives included acute & late GI & GU toxicity. Methods: RTOG 0938 is a randomized phase II study of CaP patients(pts), (Gleason score 2-6, stage T1-2a & PSA < 10 ng/mL) receiving 36.25 Gy (5 fr of 7.25 Gy in 2 wks), or 51.6 Gy (12 fr of 4.3 Gy in 2.5 wks). Pts were stratified according to RT technique – Cyberknife vs IMRT/VMAT or protons. A change in EPIC bowel domain score (baseline to 1-year) > 5 points & in EPIC urinary domain score > 2 points were felt to be clinically significant. The frequency for > 5 point change in bowel score (FREQE-B) in ≤ 35% of pts was considered acceptable, with the frequency ≥ 55% unacceptable. Similarly, the frequency for > 2 point change in urinary score (FREQE-U) in ≤ 40% was considered acceptable, with the frequency ≥ 60% unacceptable. A sample size of 156 pts was needed for 95% power with one-sided significance level of 0.025 to preserve an overall level of 0.05. Results: 240 pts were enrolled to ensure adequacy of data for analysis. The compliance for HRQOL completion was good ( > 80%). The 1 year FREQE-B for 5 fr was 23.5% (p < 0.001) & 12 fr was 23.1% (p < 0.001). The 1 year FREQE-U for 5 fr was 35.3% (p < 0.001) & 12 fr was 34.7% (p < 0.001). Conclusions: This study confirms that based on changes in EPIC B&U (baseline to 1-year), acute & late toxicity, both the 5 & 12 fr regimens are well tolerated. These UHR need to be compared to current SRTR in the context of a RCT with efficacy & toxicity endpoints. Supported by grants U10CA21661, U10CA180868, U10CA180822, U10CA37422, UG1CA189867 from the National Cancer Institute (NCI). Clinical trial information: NCT01434290. [Table: see text]

Evaluation of preoperative ProstaScint scans in the prediction of nodal disease

Diagnostic methods are limited for detecting microscopic soft tissue metastases in patients with prostate cancer. Previous studies using (111)Indium Capromab Pendetide (ProstaScint scan) analyzed patients with extensive localized tumor (prostate specific antigen (PSA) >20 ng/ml) not optimal for surgical therapy. We evaluated the role of the ProstaScint trade mark scan in a preoperative population to provide histological documentation and to assess its utility in a surgical population. A total of 22 preoperative patients, underwent a ProstaScint scan. The mean preoperative PSA was 16.0 ng/ml (range 3.9-33 ng/ml). The mean Gleason score at biopsy was 6.9 (range 6-9). Each patient underwent a radical retropubic prostatectomy and bilateral pelvic lymph node dissection, which included resection of both obturator and common iliac lymph nodes. Histologic analysis of the resected lymph nodes provided the standard of comparison with the ProstaScint scan. The results of the scan and pathology for all 22 patients were compared with the bilateral obturator and iliac nodes, creating 88 data points. Nine areas (10%) were positive on the scan. One of these (11%) was a true positive while the other eight (89%) were false positives. Seventy-nine areas (90%) were negative on scan results. Of these, five areas (6%) were false negatives and 74 areas (94%) were true negatives. The scan yielded a sensitivity of 17%, specificity of 90%, negative predictive value (NPV) of 94% and a positive predictive value (PPV) of 11%. The high false positive rate and low PPV of ProstaScint scans overestimates metastatic lymph nodes disease, and is not useful when used preoperatively.

Variable definitions influence the reporting of biochemical failure rates

The purpose of this study was to assess how the reporting of biochemical failure (BF) rates would be affected by the application of three different definitions. Three hundred and fifteen men with localized prostate cancer underwent I-125 brachytherapy (n=109), conformal three-dimensional radiation therapy (n=99), or radical prostatectomy (n=107). No patient received adjuvant or neoadjuvant hormone therapy in this study. BF rates at 12, 24 and 36 months were assessed using three definitions: (1) prostate-specific antigen (PSA) nadir >0.5 ng/ml; (2) PSA rise by 0.5 ng/ml; and (3) three consecutive PSA rises. Median follow-up for the brachytherapy group, external beam radiotherapy group, and the radical prostatectomy group was 27, 30 and 36 months respectively. The applied definition influenced reporting of failure rates in two of the three groups. I-125 brachytherapy group: BF rates at 24 months: 46%-definition 1, 35%-definition 2, and 4%-definition 3 (P<0.05). Radiation therapy group: BF rates at 24 months: 39%-definition 1, 17%-definition 2 and 3%-definition 3 (P<0.05). No patient in the radical prostatectomy group had a BF by any applied definition. A more universal definition of BF is needed to compare the efficacy of treatments for localized prostate cancer.

Laparoscopic cross-trigonal Cohen ureteroneocystostomy: novel technique

PURPOSE

We describe a novel technique of laparoscopic transvesical cross-trigonal Cohen anti-reflux ureteroneocystostomy.

MATERIALS AND METHODS

A 10, an 11 and a 32-year-old patient with symptomatic unilateral vesicoureteral reflux underwent laparoscopic cross-trigonal ureteral reimplantation. Two 5 mm. balloon tip ports were suprapubically inserted into the bladder. Using a transurethral resectoscope with a Collins knife a 4 to 5 cm. cross-trigonal submucosal trough was created from the refluxing ureteral orifice to the contralateral side of the bladder. The refluxing ureteral orifice and intramural ureter were completely mobilized intravesically, advanced transtrigonally and secured to the detrusor muscle at the apex of the trough with 3 deep interrupted sutures. The elevated mucosal flaps of the trough were suture approximated over the ureter to create a submucosal tunnel. All suturing was performed by freehand laparoscopic technique.

RESULTS

Operative time was between 2.5 and 4.5 hours and blood loss was 10 to 50 cc. Adequate submucosal trough creation, ureteral extravesical mobilization and intravesical advancement, and bladder mucosal flap reapproximation were done to create a submucosal tunnel in all cases. Satisfactory transtrigonal anchoring of the neoureteral orifice to the detrusor muscle and mucosa was achieved with 3 stitches. Hospital stay was 2, 2 and 1 days in the 3 cases, and the Foley catheter remained in place for 3, 1 and 1 week, respectively. At 6 months reflux had resolved in 2 patients, while in 1 grade II reflux persisted, which was improved from grade IV preoperatively. All patients have remained infection-free without antibiotics.

CONCLUSIONS

Laparoscopic transvesical cross-trigonal antireflux ureteral reimplantation is technically feasible. Intravesical laparoscopic suturing is possible. Potential advantages include a decreased hospital stay, decreased narcotic requirement and better cosmesis. Further experience is necessary to refine the technical nuances and evaluate outcomes compared to the open technique.

Screening and monitoring for bladder cancer: refining the use of NMP22

PURPOSE

While detecting bladder cancer, bladder tumor markers demonstrate improved sensitivity compared with urinary cytology but the current limitation is the low specificity and positive predictive value, that is high false-positive rate. We examined the clinical categories of the false-positive results, established relative exclusion criteria, and recalculated the specificity and positive predictive value of this assay with these criteria.

MATERIALS AND METHODS

A total of 608 patients considered at risk for bladder cancer presented to a urology clinic and submitted a single urine sample. Of the 608 patients 529 (87%) presented with de novo hematuria or chronic voiding symptoms without a diagnosis of bladder cancer. There were 79 (13.0%) patients being monitored with a known history of bladder cancer. Each urine sample was examined via cytology, urinalysis, culture and NMP22 protein assay. All patients underwent office cystoscopy, and transurethral resection and/or biopsy if a bladder tumor was suspected.

RESULTS

Of the 608 patients 226 (37.2%) presented with microscopic hematuria, 143 (23.5%) with gross hematuria and 239 (39.3%) had chronic symptoms of urinary frequency or dysuria. There were 52 (8.6%) patients who had histologically confirmed bladder cancer. Of these 52 cancers NMP22 detected 46 (88.5%), whereas cytology identified only 16 (30.8%). When atypical cytology was considered positive, cytology detected 32 (61.5%) cases. In the 135 patients with increased NMP22 values the 46 identified tumors were accompanied by 89 false-positive values yielding a specificity of 83.9% and a positive predictive value of 34.1%. These false-positive results were divided into 6 clinical categories. Exclusion of these categories improved the specificity and positive predictive value of NMP22 to 99.2% and 92.0%, respectively, yielding results similar to urinary cytology (99.8% and 94.1%).

CONCLUSIONS

Awareness and exclusion of the categories of false-positive results can increase the specificity and positive predictive value of NMP22, enhancing the clinical use of this urinary tumor marker.

Contemporary "urologic" intervention in the pancreaticobiliary tree

OBJECTIVES

To evaluate the role of minimally invasive "urologic" interventional techniques for the treatment of pancreaticobiliary calculi in contemporary practice.

METHODS

Fourteen patients with retained cystic duct (n = 2), hepatic duct (n = 5), common duct (n = 2), pancreatic duct (n = 4), or gallbladder (n = 1) calculi were treated with 19 procedures, including shock wave lithotripsy (n = 9) and percutaneous flexible endoscopy with electrohydraulic or holmium laser lithotripsy (n = 10). Previous attempts using standard gastroenterologic or radiologic interventions before the urologic referral had failed in all 14 patients.

RESULTS

A successful result, defined by the resolution of stones and symptoms, was achieved in 12 patients (86%); 2 patients (14%) had residual calculi that ultimately required an open operative procedure. The hospital stay for each intervention was 0 to 2 nights, and no patients had any significant complications.

CONCLUSIONS

Even in this age of advanced gastroenterologic technology, including laparoscopic cholecystectomy, endoscopic retrograde cholangiopancreatoscopy, and percutaneous transhepatic cholangiography, the urologist can play a significant role in the minimally invasive treatment of patients with complicated biliary disease such that the need for open operative "salvage" procedures will be further minimized.

Penile adhesions after neonatal circumcision

PURPOSE

The appropriate management of penile adhesions in circumcised boys is unclear. An important consideration is whether adhesions resolve spontaneously. We studied the incidence of penile adhesions as a function of patient age to assess the natural history.

MATERIALS AND METHODS

We evaluated all circumcised boys presenting to our pediatric urology clinic. A standard form was used to classify adhesions as grade 0-no adhesions, 1-fine adhesions to the corona, 2-adhesions covering less than 50% of the glans and 3-adhesions covering greater than 50% of the glans. All boys were evaluated by 1 of 2 pediatric urologists. Previous treatment of adhesions was assessed and skin bridges were also noted.

RESULTS

We enrolled in our study 254 boys 1 month to 19 years 8 months old. Only 7 patients had a history of treatment of adhesion, of whom 3 had recurrent adhesions at evaluation. Patients were divided into groups based on age, including younger than 12 months (61), 13 to 60 (78), 61 to 108 (51) and 109 months old or older (64). In these groups we noted an adhesion rate of 71%, 28%, 8% and 2%, respectively. The rate of adhesions more severe than grade 1 was 30%, 10% and 0% in boys 12 months old or younger, 13 to 60 and 61 months old or older, respectively. The oldest patient with grade 3 adhesions was 31 months old. Skin bridges in 6 cases involved the circumcision line in 4.

CONCLUSIONS

Penile adhesions develop after circumcision and the incidence decreases with patient age. Although there is debate on whether to lyse these adhesions manually, our findings suggest that adhesions resolve without treatment. Based on our results we do not recommend lysing penile adhesions, except perhaps those involving the circumcision line.