Aaron Brant

KRAS and Guanine Nucleotide-Binding Protein Mutations in Pancreatic Juice Collected From the Duodenum of Patients at High Risk for Neoplasia Undergoing Endoscopic Ultrasound

BACKGROUND & AIMS Pancreatic imaging can identify neoplastic cysts but not microscopic neoplasms. Mutation analysis of pancreatic fluid after secretin stimulation might identify microscopic neoplasias in the pancreatic duct system. We determined the prevalence of mutations in KRAS and guanine nucleotide-binding protein α-stimulating genes in pancreatic juice from subjects undergoing endoscopic ultrasound for suspected pancreatic intraepithelial neoplasia, intraductal papillary mucinous neoplasms, or pancreatic adenocarcinoma. METHODS Secretin-stimulated juice samples were collected from the duodenum of 272 subjects enrolled in Cancer of the Pancreas Screening studies; 194 subjects were screened because of a family history of, or genetic predisposition to, pancreatic cancer, and 78 subjects were evaluated for pancreatic cancer (n = 30) or other disorders (controls: pancreatic cysts, pancreatitis, or normal pancreata, n = 48). Mutations were detected by digital high-resolution melt-curve analysis and pyrosequencing. The number of replicates containing a mutation determined the mutation score. RESULTS KRAS mutations were detected in pancreatic juice from larger percentages of subjects with pancreatic cancer (73%) or undergoing cancer screening (50%) than controls (19%) (P = .0005). A greater proportion of patients with pancreatic cancer had at least 1 KRAS mutation detected 3 or more times (47%) than screened subjects (21%) or controls (6%, P = .002). Among screened subjects, mutations in KRAS (but not guanine nucleotide-binding protein α-stimulating) were found in similar percentages of patients with or without pancreatic cysts. However, a greater proportion of patients older than age 50 years had KRAS mutations (54.6%) than younger patients (36.3%) (P = .032); the older subjects also had more mutations in KRAS (P = .02). CONCLUSIONS Mutations in KRAS are detected in pancreatic juice from the duodenum of 73% of patients with pancreatic cancer, and 50% of asymptomatic individuals with a high risk for pancreatic cancer. However, KRAS mutations were detected in pancreatic juice from 19% of controls. Mutations detected in individuals without pancreatic abnormalities, based on imaging analyses, likely arise from small pancreatic intraepithelial neoplasia lesions. ClinicalTrials.gov no: NCT00438906 and NCT00714701.

Digital next-generation sequencing identifies low-abundance mutations in pancreatic juice samples collected from the duodenum of patients with pancreatic cancer and intraductal papillary mucinous neoplasms

Objective Secretin-stimulated pancreatic juice contains DNA shed from cells lining the pancreatic ducts. Genetic analysis of this fluid may form a test to detect pancreatic ductal neoplasia. Design We employed digital next-generation sequencing (‘digital NGS’) to detect low-abundance mutations in secretin-stimulated juice samples collected from the duodenum of subjects enrolled in Cancer of the Pancreas Screening studies at Johns Hopkins Hospital. For each juice sample, digital NGS necessitated 96 NGS reactions sequencing nine genes. The study population included 115 subjects (53 discovery, 62 validation) (1) with pancreatic ductal adenocarcinoma (PDAC), (2) intraductal papillary mucinous neoplasm (IPMN), (3) controls with non-suspicious pancreata. Results Cases with PDAC and IPMN were more likely to have mutant DNA detected in pancreatic juice than controls (both p<0.0001); mutant DNA concentrations were higher in patients with PDAC than IPMN (p=0.003) or controls (p<0.001). TP53 and/or SMAD4 mutations were commonly detected in juice samples from patients with PDAC and were not detected in controls (p<0.0001); mutant TP53/SMAD4 concentrations could distinguish PDAC from IPMN cases with 32.4% sensitivity, 100% specificity (area under the curve, AUC 0.73, p=0.0002) and controls (AUC 0.82, p<0.0001). Two of four patients who developed pancreatic cancer despite close surveillance had SMAD4/TP53 mutations from their cancer detected in juice samples collected over 1 year prior to their pancreatic cancer diagnosis when no suspicious pancreatic lesions were detected by imaging. Conclusions The detection in pancreatic juice of mutations important for the progression of low-grade dysplasia to high-grade dysplasia and invasive pancreatic cancer may improve the management of patients undergoing pancreatic screening and surveillance.

Deleterious Germline Mutations in Patients With Apparently Sporadic Pancreatic Adenocarcinoma

Purpose Deleterious germline mutations contribute to pancreatic cancer susceptibility and are well documented in families in which multiple members have had pancreatic cancer. Methods To define the prevalence of these germline mutations in patients with apparently sporadic pancreatic cancer, we sequenced 32 genes, including known pancreatic cancer susceptibility genes, in DNA prepared from normal tissue obtained from 854 patients with pancreatic ductal adenocarcinoma, 288 patients with other pancreatic and periampullary neoplasms, and 51 patients with non-neoplastic diseases who underwent pancreatic resection at Johns Hopkins Hospital between 2000 and 2015. Results Thirty-three (3.9%; 95% CI, 3.0% to 5.8%) of 854 patients with pancreatic cancer had a deleterious germline mutation, 31 (3.5%) of which affected known familial pancreatic cancer susceptibility genes: BRCA2 (12 patients), ATM (10 patients), BRCA1 (3 patients), PALB2 (2 patients), MLH1 (2 patients), CDKN2A (1 patient), and TP53 (1 patient). Patients with these germline mutations were younger than those without (mean ± SD, 60.8 ± 10.6 v 65.1 ± 10.5 years; P = .03). Deleterious germline mutations were also found in BUB1B (1) and BUB3 (1). Only three of these 33 patients had reported a family history of pancreatic cancer, and most did not have a cancer family history to suggest an inherited cancer syndrome. Five (1.7%) of 288 patients with other periampullary neoplasms also had a deleterious germline mutation. Conclusion Germline mutations in pancreatic cancer susceptibility genes are commonly identified in patients with pancreatic cancer without a significant family history of cancer. These deleterious pancreatic cancer susceptibility gene mutations, some of which are therapeutically targetable, will be missed if current family history guidelines are the main criteria used to determine the appropriateness of gene testing.

Pathologic response in patients receiving neoadjuvant chemotherapy for muscle-invasive bladder cancer: Is therapeutic effect owing to chemotherapy or TURBT?

PURPOSE We estimated the proportion of patients who received neoadjuvant chemotherapy for muscle-invasive bladder cancer whose tumors were downstaged by transurethral resection. MATERIALS AND METHODS We identified patients with cT2 N0 urothelial carcinoma who underwent cystectomy at our institution from 2005 to 2014-overall, 139 underwent transurethral resection without chemotherapy, and 146 underwent transurethral resection with chemotherapy. Pathologic response was defined as<pT2 N0. We used a Poisson regression model to determine relative risk (RR) of pathologic response in nonneoadjuvant vs. neoadjuvant patients, adjusting for demographic and clinical covariates. This RR was used to estimate the response attributable to transurethral resection. RESULTS Neoadjuvant patients were younger than nonneoadjuvant patients (64.4 vs. 71.4 years, P<0.01), with higher median body mass index (28.4 vs. 26.6kg/m2, P<0.01), lower prevalence of Charlson score≥3 (13.7% vs. 30.2%, P<0.01), and lower prevalence of prior non-muscle-invasive cancer (7.5% vs. 20.9%, P<0.01). More neoadjuvant patients achieved response compared with nonneoadjuvant patients (62.3% vs. 20.1%, RR = 3.10, P<0.01). Adjustment resulted in a RR of pathologic response in neoadjuvant vs. nonneoadjuvant patients of 2.60 (95% CI: 1.81-3.74, P<0.01). This adjusted RR indicates that among patients who receive neoadjuvant chemotherapy and undergo transurethral resection, 38% (95% CI: 27%-55%) of pathologic response can be attributed to transurethral resection. CONCLUSIONS We estimate that in a cohort of patients who receive chemotherapy and undergo transurethral resection before cystectomy, 38% of pathologic response can be attributed to transurethral resection. Understanding who responds to chemotherapy and who responds to transurethral resection is needed to measure the effectiveness of both interventions.

Assessing Cancer Progression and Stable Disease After Neoadjuvant Chemotherapy for Organ-confined Muscle-invasive Bladder Cancer

OBJECTIVE To propose and validate a new approach to stratify clinically staged, organ-confined, muscle-invasive bladder cancer patients (cT2N0M0) who are pathologic non-responders to neoadjuvant chemotherapy (NAC) to better characterize NAC non-response. METHODS We retrospectively identified radical cystectomy patients with cT2N0M0 disease at our institution (2005-2014) and in the National Cancer Database (2004-2012) for external validation. Patients were stratified as stable (pT2N0M0) or progressors (>pT2 or pN+). The primary end points were cancer-specific survival (CSS), overall survival (OS), and recurrence-free survival (RFS). RESULTS In the institutional cohort, NAC stable patients (n = 17) had better OS (P = .05) and RFS (P = .04) than NAC progressors (n = 50), and had comparable OS (P = .7) and CSS (P = .09) with non-NAC stable patients (n = 27). Multivariable Cox proportional hazard models showed that larger tumor size predicted worse OS (hazard ratio [HR] = 1.20 per centimeter, 95% confidence interval [CI: 1.07, 1.35]), CSS (HR = 1.27, 95% CI [1.11, 1.45]), and RFS (HR = 1.24, 95% CI [1.09, 1.42]). Similarly, in the National Cancer Database, NAC stable patients (n = 223) had improved OS (P < .0001) compared with NAC progressors (n = 232) and comparable (P = .4) OS with non-NAC stable patients (n = 950). Multivariable Cox proportional hazard model showed that larger tumor size (HR = 1.03 per centimeter, 95% CI [1.02, 1.03]) and progression (HR = 2.69, 95% CI [2.40, 3.01]) predicted worse OS. CONCLUSION Distinct survival outcomes suggest that NAC non-responders should be further stratified into stable disease and progressors. Comparable survival between non-NAC and NAC stable disease patients suggests that NAC stable disease may represent a chemoresistant but more indolent phenotype on the disease spectrum. Moreover, tumor size is an important prognostic biomarker in NAC non-responders. Clinical predictors of disease progression on NAC were not identified, highlighting the need to explore molecular and genomic subtyping determinants of disease progression.

Obstructive Sleep Apnea and Pathological Characteristics of Resected Pancreatic Ductal Adenocarcinoma

Background Prospective studies have identified obstructive sleep apnea (OSA) as a risk factor for increased overall cancer incidence and mortality. The potential role of OSA in the risk or progression of specific cancers is not well known. We hypothesized that pathological differences in pancreatic cancers from OSA cases compared to non-OSA cases would implicate OSA in pancreatic cancer progression. Methods We reviewed the medical records of 1031 patients who underwent surgical resection without neoadjuvant therapy for pancreatic ductal adenocarcinoma (PDAC) at Johns Hopkins Hospital between 2003 and 2014 and compared the TNM classification of their cancer and their overall survival by patient OSA status. Results OSA cases were significantly more likely than non-OSA cases to have lymph node-negative tumors (37.7% vs. 21.8%, p = 0.004). Differences in the prevalence of nodal involvement of OSA vs. non-OSA cases were not associated with differences in other pathological characteristics such as tumor size, tumor location, resection margin status, vascular or perineural invasion, or other comorbidities more common to OSA cases (BMI, smoking, diabetes). A logistic regression model found that a diagnosis of OSA was an independent predictor of lymph node status (hazard ratio, 0.051, p = 0.038). Patients with OSA had similar overall survival compared to those without OSA (HR, 0.89, (0.65–1.24), p = 0.41). Conclusion The observed pathological differences between OSA-associated and non-OSA-associated pancreatic cancers supports the hypothesis that OSA can influence the pathologic features of pancreatic ductal adenocarcinoma.

Lack of association between the pancreatitis risk allele CEL-HYB and pancreatic cancer

CEL-HYB is a hybrid allele that arose from a crossover between the 3’ end of the Carboxyl ester lipase (CEL) gene and the nearby CEL pseudogene (CELP) and was recently identified as a risk factor for chronic pancreatitis. Since chronic pancreatitis is a risk factor for the development of pancreatic cancer, we compared the prevalence of the CEL-HYB allele in patients with pancreatic ductal adenocarcinoma to spousal controls and disease controls. The CEL-HYB allele was detected using Sanger and next generation sequencing. There was no significant difference in the prevalence of the CEL-HYB allele between cases with pancreatic ductal adenocarcinoma compared to controls; 2.6% (22/850) vs. 1.8% (18/976) (p=0.35). CEL-HYB carriers were not more likely to report a history of pancreatitis. Patients with pancreatic cancer are not more likely than controls to be carriers of the CEL-HYB allele.

Patient Decision-Making and Predictors of Genital Satisfaction Associated with Testicular Prostheses after Radical Orchiectomy: a Questionnaire-Based Study of Men with Germ Cell Tumors of the Testicle

OBJECTIVE To better understand patient decision-making and genital satisfaction associated with postorchiectomy testicular prosthesis (TP) implantation in patients with germ cell tumors of the testicle. MATERIALS AND METHODS An electronic survey to assess TP decision-making and genital satisfaction was distributed to patients via an institutional database (n = 70) and social media outlets (n = 167). Statistical analyses were performed using chi-square tests for categorical variables, Wilcoxon-Mann-Whitney tests for continuous variables, and multivariate regression analyses to identify independent predictors of receiving a prosthesis, genital satisfaction, and prosthesis satisfaction. RESULTS 24.9% of respondents elected to receive a TP, but 42% of men without a prosthesis reported never being offered one. Identifying as a heterosexual man (2.86) and receiving a TP (odds ratio = 3.29) were both positive predictors of overall genital satisfaction. Having the orchiectomy performed at an academic institution (odds ratio = 2.87) was a positive predictor of testicular prosthesis TP placement. 89.8% of TP recipients were satisfied with the look of their prosthetic, but only 59.3% of respondents were satisfied with prosthetic feel. CONCLUSION There are high levels of genital satisfaction in those who elect to receive a TP postorchiectomy. Associations between TP placement, genital satisfaction, and sexuality merit further investigation. Our results also indicate that patients who pursue an orchiectomy at an academic institution are more likely to receive a TP. The use of social media to recruit study participants in urology should be explored further.

PD57-12 A COMPARISON OF POST-CYSTECTOMY RECURRENCE AND SURVIVAL IN NAC-RESPONSIVE MIBC VS. HIGH-RISK NMIBC PATIENTS: SIMILAR PATHOLOGIC STAGE YET DIFFERENT OUTCOMES

INTRODUCTION AND OBJECTIVES: Patient reports of health related quality of life (HRQoL) are being used to facilitate understanding of the physical and psychological impacts of surgery in patients with bladder cancer. Presently, the true effect of radical cystectomy (RC) on female sexual function is poorly described. The aim of this study is to prospectively report baseline and post-operative sexual function in a group of females undergoing RC. METHODS: Seventy-four females undergoing RC for bladder cancer were enrolled from 2008-2014 in a prospective HRQoL study. The Female Sexual Function Index (FSFI) was administered 1 month prior to RC, 6and 12-months post-operatively. Latent Transition Analysis (LTA) was conducted at all 3 points in time to assign patients to homogeneous groups based on their survey responses (i.e., patients with similar responses were grouped together). Group membership was modeled by marital status, type of urinary diversion, vaginal reconstruction, and administration of neoadjuvant chemotherapy. LTA was also used to estimate transitions between groups over time. RESULTS: Sixty patients completed baseline surveys and 47 (64%) one year following cystectomy. Median age of the cohort was 66 (IQR 59,72) and 62 patients (84%) underwent vaginal reconstruction with RC. LTA revealed that at baseline, 65% of patients provided responses that were characterized as having 0no sexual activity0 (group 1), 17% 0 limited sexual function0 (group 2), and 18% 0adequate sexual function0 (group 3). The distributions were stable one year after RC (65%, 21%, and 14% for the 3 groups, respectively). Analyzing transitions between preop grouping and at 1 year revealed that 44% of patients with adequate sexual function (group 3) remained unchanged. In group 2, 33% remained in the same category, while 21% transitioned to group 3. For patients reporting no sexual activity pre-op, 87% remained in the same category at 1 year, but 8% and 5% transitioned to groups 2 & 3 respectively. Being married was significantly associated with sexual function after surgery (p<0.001). No significant association was found based on the type of urinary diversion, vaginal reconstruction, or neoadjuvant chemotherapy. CONCLUSIONS: Although a large proportion of females are not sexually active either before or after RC, one third of patients in this study maintained sexual function, with a small proportion demonstrating improvement at 1 year. Enhanced understanding of pre-op and post-op sexual function can lead to improved peri-operative counseling & surgical planning for sexually active females undergoing RC.

High dose-rate intra-operative radiation therapy during high risk genitourinary surgery: Initial observations and a proposal for its study in bladder cancer

Background: High dose-rate Intra-Operative Radiation Therapy (HD-IORT) is used to provide effective local control for patients with high-risk locally advanced or recurrent tumors. However, the utility of HD-IORT for patients with bladder cancer has not been studied. Objective: To characterize our institutional experience with HD-IORT in patients with cancer requiring genitourinary surgery, in an effort to identify patients with bladder cancer that may benefit from HD-IORT. Methods: We performed a retrospective review of all patients who have undergone HD-IORT during genitourinary surgery at our institution. Patients were stratified by surgical margin status, and primary outcomes assessed were overall survival, recurrence free survival and 90-day complications. Patients undergoing cystectomy and HD-IORT with sarcomatoid urothelial cancer were compared to a similar cohort undergoing cystectomy alone. A sample case of one such patient is discussed in detail. Results: 84 patients at our institution have undergone HD-IORT with genitourinary surgery. Positive surgical margin status was the greatest predictor of both OS (HR = 3.42) and RFS (HR = 2.61). The overall 90-day complication rate was 61%, with wound infections (43%) and GI complications (21%) being most common. 4 of these patients had sarcomatoid urothelial histology, and all are still alive with >2 yrs follow up. This compares to a 52% 1 yr survival in our sarcomatoid urothelial cohort (25 pts) that did not undergo HD-IORT. Conclusions: Our institutional experience with HD-IORT has been promising, particularly among patients with locally advanced disease and sarcomatoid histology. We are currently enrolling patients in a multi-institutional registry to assess the utility of HD-IORT in high risk bladder cancer.