Oral Toxicities of PSMA-Targeted Immunotherapies for The Management of Prostate Cancer

INTRODUCTION

Prostate Specific Membrane Antigen (PSMA)-targeted radionucleotide therapy has been shown to cause dry mouth, but the oral manifestations of PSMA-targeted immunotherapy have not been extensively studied. The aim of this study was to describe and quantify the oral manifestations of PSMA-targeted immunotherapies (bispecific antibodies or Chimeric Antigen Receptor T cell therapies) in the management of metastatic castration resistant prostate cancer.

PATIENTS AND METHODS

We performed a retrospective analysis of the oral toxicities of PSMA-targeted immunotherapies of the patients seen at a single institution's cancer center between 2020 and 2023. Descriptive statistics were used to summarize the data.

RESULTS

In a total of 19 patients treated with PSMA-targeted immunotherapies between 2020 and 2023, 9 patients (47%) experienced the following oral toxicities: xerostomia (n = 6; 32%), mucositis (n = 2; 10%), dysgeusia, dry throat and teeth sensitivity in (n = 1 each; 5%), respectively. Oral infections, such as candidiasis and herpes simplex, were not observed in any patients. Mucositis was managed with salt rinses and resolved within few months from onset. Xerostomia persisted in all the patients (median: 306 days, range: 98-484 days) among those who reported dry mouth at the time of data collection, despite treatment with salivary stimulants (n = 5; 83%). Dysgeusia was also persistent, although it was not specifically treated.

CONCLUSIONS

Patients treated with PSMA-targeted immunotherapies for prostate cancer can present with various short-term and long-term off-tumor on-target oral toxicities including xerostomia and dysgeusia that may affect quality of life. This study serves as a foundation to future prospective studies with a larger sample size and also helps oncologists managing prostate cancer patients with targeted immunotherapies to familiarize common oral toxicities. Furthermore, we emphasize the importance of oral medicine consultation for a comprehensive oral examination and management of oral complications.

Investigating the research capacity and productivity of Canadian sports chiropractors

Objectives

To investigate the research capacity and productivity of Canadian sports chiropractors.

Methods

A cross-sectional survey (phase one) and scoping review (phase two) investigated the research capacity and productivity (from 2015-2020) of the Canadian sports chiropractic field.

Results

Most respondents (72%) reported obtaining research training from fellowship and master's programs, with only 2 (1%) PhD qualifications identified. Approximately, 30% reported active involvement in research, with 28% being part-time clinician researchers. Access to human and technological research resources were limited. We identified 67 publications and 16 conference presentations within a five-year period, with clinical, population health, and basic science research as the areas most studied.

Conclusion

The research effort of Canadian sports chiropractors is primarily conducted by clinicians involved in research on a part-time basis. Its research outputs predominantly reflect the research requirements of the RCCSS(C) Sports Sciences Residency Program, highlighting its contribution in developing capacity and producing research for the Canadian sports chiropractic field.

Risk factors of multiple pulmonary emboli in an elite Ironman triathlete: a case report

Objective

To present a unique case of pulmonary embolism (PE) in an elite-Ironman triathlete and review athlete-specific risk factors associated with venous thromboembolism (VTE).

Case presentation

A 57-year-old male triathlete presented for chiropractic care of midback pain and dyspnea one day before competition. During competition, he was removed and unable to complete the event with dyspnea, chest, and midback pain. Vitals revealed prolonged elevated resting heart rate. He was triaged to the hospital with a high index of suspicion for PE. He was diagnosed with multiple PE in both lungs.

Summary

VTE is not normally considered in athletes. A combination of athlete-specific risk factors may predispose athletes to a higher propensity of VTE. Due to life-threatening consequences, it is important to include a differential diagnosis of VTE in patients presenting with midback pain and dyspnea.

Single-dose 177Lu-PSMA-617 followed by maintenance pembrolizumab in patients with metastatic castration-resistant prostate cancer: an open-label, dose-expansion, phase 1 trial

BACKGROUND

Checkpoint inhibitors have been shown to have limited activity in patients with metastatic castration-resistant prostate cancer. We aimed to determine whether a single dose of lutetium-177 [177Lu]-prostate-specific membrane antigen (PSMA)-617 (177Lu-PSMA-617) followed by maintenance pembrolizumab was safe and could induce durable clinical benefit.

METHODS

We did an open-label, dose-expansion, phase 1 study at the University of California, San Francisco (San Fransisco, CA, USA). Eligible patients were men aged 18 years or older with progressive metastatic castration-resistant prostate cancer who had an Eastern Cooperative Oncology Group performance status of 0 or 1, had progression on one or more androgen signalling inhibitors, and at least three PSMA-avid lesions on 68Ga-PSMA-11 positron emission tomography. In part A, patients were enrolled sequentially to one of three schedules in which a single dose of 177Lu-PSMA-617 (7·4 GBq) was given intravenously 28 days before (schedule 1), concomitant with (schedule 2), or 21 days after (schedule 3) the start of maintenance intravenous pembrolizumab (200 mg every 3 weeks). In part B, 25 patients were enrolled using the recommended phase 2 schedule. The primary endpoint in part A was determination of the recommended phase 2 schedule, and in part B, the objective response rate. The analysis set included all patients who received at least one dose of pembrolizumab or 177Lu-PSMA-617. This study is registered with ClinicalTrials.gov, NCT03805594.

FINDINGS

Between Aug 8, 2019 and May 7, 2022, 43 male patients were enrolled (n=18 part A [six patients per schedule]; n=25 part B), with a median follow-up of 16·5 months (IQR 12·2-21·9). Schedule 1 was selected as the recommended phase 2 schedule for part B, on the basis of safety and feasibility of administration observed in part A. In part B, 14 (56%; 95% CI 35-76) of 25 patients had a confirmed objective response. Two (5%) of 43 patients had a treatment-related adverse event of grade 3 or worse (grade 3 arthritis in schedule 2, grade 3 pneumonitis in schedule 3). One serious adverse event (one death due to aspiration pneumonia) and no treatment-related deaths were observed.

INTERPRETATION

A single priming dose of 177Lu-PSMA-617 followed by pembrolizumab maintenance was safe and had encouraging preliminary activity in patients with metastatic castration-resistant prostate cancer.

FUNDING

Prostate Cancer Foundation, National Cancer Institute, Novartis Pharmaceuticals, and Merck.

Utilization of Regional Anesthesia in the Electrophysiology Lab: A Narrative Review

PURPOSE OF REVIEW

The electrophysiology lab is an important source of growth of anesthetic volume as the indications and evidence for catheter ablations and various cardiac implantable electronic devices improve. Paired with this increase in volume is an increasing number of patients with substantial comorbid conditions presenting for their EP procedures. For these patients, the interaction between their comorbidities and traditional anesthesia practices may create the risk of hemodynamic instability, cardiovascular or respiratory complications, and potential need for prolonged post-operative monitoring negatively impacting length of hospital stay.

RECENT FINDINGS

Regional anesthetic techniques, including pectoralis, serratus, and erector spinae plane blocks, offer options for both regional analgesia and surgical anesthesia for a variety of EP procedures. Existing case reports and extrapolations from other areas support these techniques as viable, safe, and effective components of an anesthetic plan. In this article, we will review the development and challenges of various EP procedures and how different regional anesthetic techniques can function as a component of the anesthesia plan.

Impact of anemia on acute ischemic stroke outcomes: A systematic review of the literature

INTRODUCTION

Anemia has been reported in nearly 40% of acute ischemic stroke (AIS) patients and is linked to significant morbidity and disability. The presence of anemia is associated with worse outcomes in AIS, specifically in the presence of large vessel occlusion (LVO). An optimal hemoglobin (Hb) target specific to this pathology has not yet been established. The goal of this review is to systematically review literature that observes the association that exists between AIS outcomes and hemoglobin (Hb) levels.

METHODS

A systematic review was performed in accordance with guidelines for the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) to identify studies from 2008-2022. The following inclusion and exclusion criteria were used: studies of adult patients with AIS; must describe outcomes with regard to Hb levels in AIS (not limited to LVO); must be written in English. The clinical variables extracted included Length of Stay (LOS), modified rankin score (mRS), Hb levels, and mortality.

RESULTS

A total of 1,154 studies were gathered, with 116 undergoing full text review. 31 studies were included in this review. The age of patients ranged from 61.4 to 77.8. The presence of anemia in AIS increased LOS by 1.7 days on average and these patients also have a 15.2% higher rate of mortality at one year, on average.

DISCUSSION

This data suggests that the contemporary thresholds for treating anemia in AIS patients may be inadequate because anemia is strongly associated with poor outcomes (e.g., mRS>2 or mortality) and increased LOS in AIS patients. The current generalized Hb threshold for transfusion (7 g/dL) is also used in AIS patients, however, a more aggressive transfusion parameter should be further explored based on these findings. Further studies are required to confirm these findings and to determine if a more liberal RBCT threshold will result in clinical benefits.

Identifying and prioritizing research to inform a research agenda for Canadian chiropractors working in sport - the Canadian sports chiropractic perspective

Objectives

To identify and prioritize research to inform research agenda development for Canadian chiropractors working in sport.

Methods

Clinicians, researchers and leaders from the Canadian sports chiropractic field were invited to participate in 1) a survey to refine a list of research priorities, 2) a Delphi procedure to determine consensus on these priorities, and 3) a prioritization survey.

Results

The top three research priorities were 1) effects of interventions on athletic outcomes, 2) research about sports healthcare teams, and 3) clinical research related to spinal manipulative and mobilization therapy. The three highest ranked conditions to research were 1) low back pain, 2) neck pain, and 3) concussion. Collaborations with sports physicians and universities/ colleges were rated as important research collaborations to pursue.

Conclusions

These results represent the Canadian sports chiropractic perspective to research priority setting and will be used alongside stakeholder input to set the first research agenda for the Canadian sports chiropractic field.

Symptomatic tibial tunnel ganglion cyst presenting four years following an ACL hamstring autograft reconstruction: a case report of a rare complication of ACL surgery

Objective

To highlight a case of an athlete with a symptomatic pretibial cyst 4-years post-ACL reconstruction surgery.

Case presentation

A 23-year-old female soccer athlete presented with right-sided knee pain, locking and catching, and diminished sensation along the anteroinferior knee. She had a history of an ipsilateral ACL hamstring autograft four years prior. Physical evaluation revealed a visible and palpable swelling medial to the patellar tendon, limited and painful range, and hypoesthesia within the infrapatellar branch of the saphenous nerve. MRI revealed a tubular ganglion cyst along the anterior aspect of the tibial tunnel, medial to the patellar tendon, and anterior to the ACL graft.

Summary

Post-surgical ganglion cyst formation in the reconstructed ACL is a rare complication that can present years following ACL surgery. This case aims to bring awareness to this condition as a potential long-term complication in the ACL-reconstructed athlete.

Abstract A006: Modeling the impact of driver mutations on local tumor heterogeneity

Tumors consist of an accumulation of somatic mutations, some of which are “passenger” mutations which do not contribute to positive selection of cancer cells and others of which are “driver” mutations which confer a growth advantage, the benefit of which may vary depending on the type of mutation, to tumor cells. As genomic sequencing to identify driver mutations is typically only done on small samples of a tumor, identification of these driver mutations may be complicated by intra-tumor spatial heterogeneity. With this in mind, we decided to create a basic model of different classes of driver mutations to investigate the impact of the timing and type of these mutations on tumor heterogeneity. Using the PhysiCell framework as a foundation, a platform developed for creating multicellular cancer models, we built a model to identify spatial trends specific to certain classes of driver mutations and distinguish them from passenger and “hitchhiker” (heritable mutations with an increased frequency due to their relation with a driver mutation) mutations. We model cells within a single, solid, non-cancer-specific tumor grown from a single cell, allowing these cells to mutate and daughter cells to potentially gain broad types of driver mutations at each division. We define three “driver” mutation classes in this model: an increase in the reproduction rate of tumor cells (defined as fitness), a decrease in the death rate of tumor cells (defined as survivability), and an increase in the motility rate of tumor cells. To investigate the distribution of common mutations, we define “common mutations” as those appearing in at least 5% of the tumor cells at end-point, when the tumor has reached 10,000 cells. To investigate spatial heterogeneity within this model, we split the tumor into 9 distinct spatial regions at the end-point of each simulation. We use these regions to assess the distribution of common, driver, and passenger mutations and quantify spatial heterogeneity. We find that in tumors with driver mutations that increase fitness or motility, we require on average fewer samples to detect all the common mutations than within tumors containing no driver mutations. On the other hand, we find that tumors containing driver mutations increasing only survivability tend to yield similar sample heterogeneity to tumors without driver mutations. These results suggest that in addition to the timing of a mutation, the type of driver mutation can have an impact on the spatial heterogeneity within a tumor which may inform biopsy strategies in clinical settings. In future work, this model could be used to observe the relationship between spatial tumor heterogeneity and the prevalence of different classes of driver mutations within different microenvironments through the implementation of hypoxic or therapeutic agent gradients. Our model could be compared with results of clinical tissue sampling data to further understanding of the impact of spatial sampling and driver mutation type on the discovery of driver mutations in different tumors and microenvironments.

Citation Format: David Oh, Steph Owen, Luka Opasic, Jacob Scott. Modeling the impact of driver mutations on local tumor heterogeneity [abstract]. In: Proceedings of the AACR Special Conference on the Evolutionary Dynamics in Carcinogenesis and Response to Therapy; 2022 Mar 14-17. Philadelphia (PA): AACR; Cancer Res 2022;82(10 Suppl):Abstract nr A006.

Characteristics and Outcomes of Recipients of Heart Transplant with Coronarvirus Disease 2019 Who Received Casirivimab Plus Imdevimab Infusion

Purpose

Heart transplant (HT) recipient are at increased risk of adverse outcomes following COVID-19 infection and may benefit from monoclonal antibody infusion to mitigate progression to clinically severe disease. The aim of this study is to describe the outcomes of HT patients who experienced mild to moderate coronavirus disease 2019 (COVID-19), with subsequent administration of casirivimab plus imdevimab administration.

Methods

A retrospective review of all HT recipients who were infected with COVID-19, and subsequently infused with monoclonal antibodies in a large academic medical center between January 1, 2021 to September 1, 2021.

Results

14 HT patients were included in the analysis. The median age was 57.5 (interquartile range [IQR], 41.5-64) years, 10 (71%) were men, and median time from HT was 3.48 (IQR, 1.00-11.82) years. Comorbid conditions included hypertension in 6 patients (43%), diabetes in 4 (29%), and chronic kidney disease in 6 (43%). Eight patients (57%) were previously vaccinated, predominantly with the Pfizer-BioNTech vaccine. Three participants (21%) were admitted after clinical progression of COVID-19. Among patients managed at the study institution, mycophenolate mofetil was discontinued in two patients (14%) and calcineurin inhibitor was maintained at previous levels in all fourteen patients (100%). Of the admitted patients, 1 was treated with high dose corticosteroids alone and 2 were treated with corticosteroids plus remdesivir. No patient required intubation. All 3 patients were discharged home and no patients in this cohort died.

Conclusion

In this single-center case series, HT patients with mild-moderate COVID-19 who were treated with monoclonal antibody infusion had a hospitalization rate of 21% and 100% survival. Further studies are required to optimize management of COVID-19 infection in the HT population.

Adjuvant durvalumab for esophageal squamous cell carcinoma after neoadjuvant chemoradiotherapy: a placebo-controlled, randomized, double-blind, phase II study

BACKGROUND

We evaluated the efficacy of adjuvant durvalumab after neoadjuvant concurrent chemoradiotherapy (CCRT) in patients with esophageal squamous cell carcinoma (ESCC).

PATIENTS AND METHODS

This randomized, double-blind, phase II study included patients with ESCC who underwent curative surgery after neoadjuvant CCRT. Patients were randomized to receive either durvalumab (20 mg/kg/i.v. every 4 weeks for 12 months) or placebo in a 1:1 ratio and were stratified by age and pathologic tumor stage. The primary endpoint was disease-free survival (DFS).

RESULTS

Between March 2016 and June 2018, 86 patients were randomized to the durvalumab (n = 45) or placebo (n = 41) arm. The median follow-up duration was 38.7 months. There was no difference in DFS [hazard ratio (HR) 1.18, 95% confidence interval (CI) 0.62-2.27, P = 0.61] or overall survival (HR 1.08, 95% CI 0.52-2.24, P = 0.85) between the two arms. Subgroup analysis was performed for patients for whom the post-CCRT programmed death-ligand 1 (PD-L1) expression profile could be assessed (n = 54). In the PD-L1-positive group, based on tumor proportion score ≥1%, durvalumab was associated with longer overall survival compared with the placebo (36-month survival rate: 94% versus 64%; HR 0.42, 95% CI 0.10-1.76), while in the PD-L1-negative group, it was associated with shorter overall survival (42% versus 55%; HR 1.53, 95% CI 0.48-4.83), showing the tendency of interaction between post-CCRT PD-L1 status and adjuvant durvalumab therapy for overall survival (interaction P = 0.18).

CONCLUSIONS

We failed to demonstrate that adjuvant durvalumab improved survival after neoadjuvant CCRT in patients with ESCC. However, post-CCRT PD-L1 expression could predict the survival of patients who receive adjuvant durvalumab after neoadjuvant CCRT, which needs to be validated.

West Nile Virus Transmission by Solid Organ Transplantation and Considerations for Organ Donor Screening Practices, United States

West Nile virus (WNV) is the most common domestic arbovirus in the United States. During 2018, WNV was transmitted through solid organ transplantation to 2 recipients who had neuroinvasive disease develop. Because of increased illness and death in transplant recipients, organ procurement organizations should consider screening during region-specific WNV transmission months.

Immune Checkpoint Blockade in Lower Gastrointestinal Cancers: A Systematic Review

BACKGROUND

Limited therapy options exist for patients with treatment-refractory metastatic colorectal or anal cancers, prompting investigation into alternative therapies. Immunotherapy in the form of immune checkpoint blockade is one such emerging treatment that has demonstrated promising results in other tumour streams.x This review aims to assess the current use of immune checkpoint blockade in patients with lower gastrointestinal tumours.

PATIENTS AND METHODS

Embase, Medline and Cochrane databases were searched for included studies. Clinical trials published in English and utilising immune checkpoint blockade for primary tumours situated in the lower gastrointestinal tract were included. Databases were searched for studies reporting on at least one of overall survival, progression-free survival or response to therapy.

RESULTS

In total, 972 abstracts were screened, with 10 studies included in the final review. Eight trials (833 patients) assessed immune checkpoint blockade in the setting of colorectal cancers. These included pembrolizumab, nivolumab, durvalumab, atezolizumab, tremelimumab and ipilimumab. A total of 20 patients across all studies achieved a complete response, and 111 patients achieved a partial response to treatment. Two trials (62 patients) assessed immune checkpoint blockade in anal cancer, utilising nivolumab and pembrolizumab. Two patients across both studies achieved a complete response, and 11 patients achieved a partial response.

CONCLUSIONS

A number of patients with advanced lower gastrointestinal tumours achieved a complete response to treatment for what would otherwise be considered palliative disease. Presented data have highlighted that particular patients may benefit from first-line or combination immunotherapy, and thus, further investigation is warranted to individualise treatment.

Blood Donation During Pregnancy Due to Anti-Ku Hemolytic Disease of the Fetus and Newborn

BACKGROUND

Management of pregnancy in patients with Kell-null phenotype can be challenging. The immune systems of these patients form an antibody that is universally reactive against the Kell Blood Group System and can cause hemolytic disease of the fetus and newborn.

METHODS

A 29-year-old woman, pregnant for the first time, developed anti-D and anti-Ku. The mother had to have labor induced when her fetus showed signs of severe anemia, but no compatible blood was available for transfusion. The induction was delayed so that a unit of blood could be collected from the mother.

RESULTS

Due to delayed cord clamping at delivery, the newborn did not have anemia and did not require a transfusion. The remaining blood was frozen for future needs.

CONCLUSION

Blood donation by a pregnant woman for potential transfusion to a newborn with anemia is safe for the mother and fetus, and is possibly the only option in hemolytic disease of the newborn due to a rare antibody.

TCR Convergence in Individuals Treated With Immune Checkpoint Inhibition for Cancer

Tumor antigen-driven selection may expand T cells having T cell receptors (TCRs) of shared antigen specificity but different amino acid or nucleotide sequence in a process known as TCR convergence. Substitution sequencing errors introduced by TCRβ (TCRB) repertoire sequencing may create artifacts resembling TCR convergence. Given the anticipated differences in substitution error rates across different next-generation sequencing platforms, the choice of platform could be consequential. To test this, we performed TCRB sequencing on the same peripheral blood mononuclear cells (PBMC) from individuals with cancer receiving anti-CTLA-4 or anti-PD-1 using an Illumina-based approach (Sequenta) and an Ion Torrent-based approach (Oncomine TCRB-LR). While both approaches found similar TCR diversity, clonality, and clonal overlap, we found that Illumina-based sequencing resulted in higher TCR convergence than with the Ion Torrent approach. To build upon this initial observation we conducted a systematic comparison of Illumina-based TCRB sequencing assays, including those employing molecular barcodes, with the Oncomine assay, revealing differences in the frequency of convergent events, purportedly artifactual rearrangements, and sensitivity of detection. Finally, we applied the Ion Torrent-based approach to evaluate clonality and convergence in a cohort of individuals receiving anti-CTLA-4 blockade for cancer. We found that clonality and convergence independently predicted response and could be combined to improve the accuracy of a logistic regression classifier. These results demonstrate the importance of the sequencing platform in assessing TCRB convergence.

Myosin IIA and formin dependent mechanosensitivity of filopodia adhesion

Filopodia, dynamic membrane protrusions driven by polymerization of an actin filament core, can adhere to the extracellular matrix and experience both external and cell-generated pulling forces. The role of such forces in filopodia adhesion is however insufficiently understood. Here, we study filopodia induced by overexpression of myosin X, typical for cancer cells. The lifetime of such filopodia positively correlates with the presence of myosin IIA filaments at the filopodia bases. Application of pulling forces to the filopodia tips through attached fibronectin-coated laser-trapped beads results in sustained growth of the filopodia. Pharmacological inhibition or knockdown of myosin IIA abolishes the filopodia adhesion to the beads. Formin inhibitor SMIFH2, which causes detachment of actin filaments from formin molecules, produces similar effect. Thus, centripetal force generated by myosin IIA filaments at the base of filopodium and transmitted to the tip through actin core in a formin-dependent fashion is required for filopodia adhesion.

Effects of whole blood leukoreduction on platelet function and hemostatic parameters

AIMS/OBJECTIVES

The aim of this study was to evaluate the hemostatic consequences of whole blood leukoreduction (LR).

BACKGROUND

Whole blood is being used for trauma resuscitation in the military, and an increasing number of civilian trauma centres across the nation. The benefits of LR, such as decreased infectious and transfusion-related complications, are well established, but the effects on hemostatic parameters remain a concern.

METHODS

Twenty-four units of whole blood were assigned to one of the four groups: non-leukoreduced (NLR), leukoreduced at 1 h and a height of 33 in. (LR-1), leukoreduced at 4 h and a height of 33 in. (LR-4(33)), or leukoreduced at 4 h and a height of 28 in. (LR-4(28)). Viscoelastic parameters, platelet aggregation, cell counts, physiological parameters and thrombin potential were evaluated immediately before and after LR, and on days 1, 7, 14 and 21 following LR.

RESULTS

The viscoelastic parameters and thrombin generation potential were unchanged between the groups. Platelet aggregation was reduced in the LR-1 group compared with NLR after 7 days. The LR-4(28) group also showed a trend of reduced platelet aggregation compared with NLR. Aggregation in LR-4(33) was similar to NLR throughout the storage time. Physiological and electrolyte changes over the whole blood storage period were not affected by LR.

CONCLUSION

Our study shows that whole blood can be LR at 4 h after collection and a height of 33 in. while maintaining platelet count and without altering platelet function and hemostatic performance.

Volumetric laser endomicroscopy and its application to Barrett's esophagus: results from a 1,000 patient registry

Volumetric laser endomicroscopy (VLE) uses optical coherence tomography (OCT) for real-time, microscopic cross-sectional imaging. A US-based multi-center registry was constructed to prospectively collect data on patients undergoing upper endoscopy during which a VLE scan was performed. The objective of this registry was to determine usage patterns of VLE in clinical practice and to estimate quantitative and qualitative performance metrics as they are applied to Barrett's esophagus (BE) management. All procedures utilized the NvisionVLE Imaging System (NinePoint Medical, Bedford, MA) which was used by investigators to identify the tissue types present, along with focal areas of concern. Following the VLE procedure, investigators were asked to answer six key questions regarding how VLE impacted each case. Statistical analyses including neoplasia diagnostic yield improvement using VLE was performed. One thousand patients were enrolled across 18 US trial sites from August 2014 through April 2016. In patients with previously diagnosed or suspected BE (894/1000), investigators used VLE and identified areas of concern not seen on white light endoscopy (WLE) in 59% of the procedures. VLE imaging also guided tissue acquisition and treatment in 71% and 54% of procedures, respectively. VLE as an adjunct modality improved the neoplasia diagnostic yield by 55% beyond the standard of care practice. In patients with no prior history of therapy, and without visual findings from other technologies, VLE-guided tissue acquisition increased neoplasia detection over random biopsies by 700%. Registry investigators reported that VLE improved the BE management process when used as an adjunct tissue acquisition and treatment guidance tool. The ability of VLE to image large segments of the esophagus with microscopic cross-sectional detail may provide additional benefits including higher yield biopsies and more efficient tissue acquisition. Clinicaltrials.gov NCT02215291.

Elastographic and echotextural characteristics of foetal lungs and liver during the final 5 days of intrauterine development in dogs

Objective was to evaluate the echotexture and characteristics during terminal development of canine foetal respiratory and hepatic systems through elastographic examinations. Fifteen pregnant bitches were evaluated by ultrasonography twice daily, from the 53rd gestational day until whelping, and images obtained from 120 to 0 h before parturition were analysed. Images of foetal lungs and liver were recorded and then used for computer-assisted analyses to determine quantitative attributes. Acoustic Radiation Force Impulse (ARFI) elastographic of internal organs were classified as 'soft' (white areas) or 'hard' (dark areas) and quantitative analyses determined the mean shear wave velocities (SWV) of foetal lungs and liver. After delivery, canine neonates were clinically evaluated, and their health status was monitored weekly until 60 days post-partum. Sonographic parameters over time were compared by ANOVA and Pearson's correlations were used to determine associations between SWVs and echotextural variables. Foetal lungs and liver had a homogeneous echotexture and pulmonary parenchyma appeared hyperechoic when compared with that of the liver. Mean numerical pixel values (NPVs) of lungs decreased from 120 to 24 h and subsequently increased until parturition (P = 0.04). Lungs and liver mean (± SD) SWVs (0.98 ± 0.12 and 0.84 ± 0.11 m/s, respectively) didn't vary (P >  0.05) over time. Fluctuations in pulmonary NPVs indicated there was a pattern corresponding to structural and functional changes that occur during the terminal stage of pre-natal canine development and hence can be a useful diagnostic tool in veterinary. Foetal lung and liver SWVs were relatively consistent and there was no detectable changes during the pre-partum period for this variable or in echotexture.

Pure laparoscopic living donor hepatectomy: Focus on 55 donors undergoing right hepatectomy

Although laparoscopic donor hepatectomy is increasingly common, few centers with substantial experience have reported the results of pure laparoscopic donor right hepatectomy (PLDRH). Here, we report the experiences of 60 consecutive liver donors undergoing pure laparoscopic donor hepatectomy (PLDH), with most undergoing right hepatectomy. None of the 60 donors who underwent PLDH had intraoperative complications and none required transfusions, reoperation, or conversion to open hepatectomy. Forty-five donors who underwent PLDRH between November 2015 and December 2016 were compared with 42 who underwent conventional donor right hepatectomy (CDRH) between May 2013 and February 2014. The total operation time was longer (330.7 vs 280.0 minutes; P < .001) and the percentage with multiple bile duct openings was higher (53.3% vs 26.2%; P = .010) in the PLDRH group. However, the length of postoperative hospital stay (8.4 vs 8.2 days; P = .495) and rate of complications (11.9% vs 8.9%; P = .733) and re-hospitalizations (4.8% vs 4.4%; P = 1.000) were similar in both groups. PLDH, including PLDRH, is feasible when performed by a highly experienced surgeon and transplant team. Further evaluation, including long-term results, may support these preliminary findings of comparative outcomes for donors undergoing PLDRH and CDRH.

Abstract 549: Clustering analysis of next-generation sequencing T cell repertoire data in sipuleucel-T treated prostate cancer patients

Immunotherapy has demonstrated significant clinical benefit in different cancers. T cells are a crucial component of the adaptive immune system and mediate anti-tumoral immunity. Antigen-specific recognition by T cells is via T cell receptor (TCR) which is the product of somatic V(D)J gene recombination with the addition/subtraction of nontemplated bases at recombination junctions. Next generation TCR sequencing effectively profiles the TCR repertoire. Currently TCR analyses quantify diversity across single clones, however, due to the low overlap of clones across samples, such analyses are limited to a single sample. Here we extend our previous analysis pipeline to track and examine TCR repertoire across time by focusing on V and J gene segments, overcoming the limitation of contemporary analytical approaches and thus obtain statistical inference across subjects directly. The published data of TCR profiling of serial peripheral blood mononuclear cells (PBMC) from three healthy subjects and five prostate cancer patients enrolled in an open-label, Phase II clinical trial of neoadjuvant sipuleucel-T (sip-T) were used as the basis of this analyses. After consolidating the clonal abundance for each combination of V and J gene segments, we calculated Pielou’s evenness, which demonstrates that sip-T treated subjects displayed greater clonal expansion compared to healthy subjects (P&lt;0.001). The Circos table viewer was used to circularly visualize the distribution of the combination of V and J gene segments. Sip-T treated subjects were successfully distinguished from healthy subjects with 12 V and J gene combinations explaining the majority of variance of the patients by applying principle components analysis (PCA). Furthermore, we developed a customized clustering workflow to cluster the combination of V and J gene segments based on the change in abundance over time, with gap statistics employed to estimate the optimal number of clusters and k-means algorithm used for partitioning. We found that for all the prostate cancer patients assessed, TCRBV06/TCRBJ01, TCRBV05/TCRBJ02 and TCRBV06/TCRBJ02, which were in the same cluster with the highest frequencies, expanded after first treatment and were maintained at high frequencies at later time points. The results demonstrate that in the setting of immune modulation after sip-T treatment, the V(D)J recombination is not entirely random, and that this non-randomness can be used to distinguish T cell repertoires from sip-T treated subjects versus healthy subjects. The use of additional information of V and J gene segments enables to investigate the profiling of TCR repertoire from a different angle and add another layer of understanding of TCR repertoire. The application of PCA and the customized clustering complete our initial workflow for TCR sequencing data.

Citation Format: Li Zhang, Sounak Chakraborty, Jason Cham, David Oh, Nadeem Sheikh, Lawrence Fong. Clustering analysis of next-generation sequencing T cell repertoire data in sipuleucel-T treated prostate cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 549. doi:10.1158/1538-7445.AM2017-549

Venous thromboembolism following L-asparaginase treatment for lymphoid malignancies in Korea

Essentials Data on venous thromboembolism (VTE) after L-asparaginase (L-asp) in Asian lymphoma are scarce. This is a population-based study in Asian patients with lymphoid disease and L-asp-related VTE. The overall incidence of L-asp-associated VTE was similar to reports on Caucasians. This first and largest study in Asians shows that mainly adult patients are at risk of thrombosis.

SUMMARY

Background L-asparaginase (L-asp)-associated venous thromboembolism (VTE) is a serious adverse complication associated with acute lymphoblastic leukemia (ALL) and lymphoma treatment. The incidence rate of L-asp-related VTE in Asian cancer patients is not well known. Methods We performed a population-based study between 2009 and 2013 using claim databases, including both diagnostic and medication codes, such as anti-cancer treatment with L-asp and VTE diagnoses from the starting date until 3 months after cessation of L-asp. Results A total of 3286 patients were prescribed L-asp treatment for any type of lymphoid malignancy including ALL and lymphoma; 116 patients (3.5%) experienced VTE. The most common site of thrombosis was the upper extremities (34.5%). Cerebral vein thrombosis (1.7%) occurred in two pediatric patients; 2.4% (43/1795) of pediatric patients and 4.9% (72/1486) of adult patients suffered from VTE, respectively; 2.7% (56/2064) of ALL and 4.9% (59/1217) of lymphoma patients were diagnosed with VTE after L-asp exposure. After univariate analysis, both the diagnosis of lymphoma (vs. ALL) and being an adult patient (vs. pediatric patient) were risk factors for VTE occurrence. However, after multivariate analysis, only age > 18 remained a risk factor for VTE (odds ratio, 1.79; 95% confidence interval, 1.14-2.81). Conclusions This is the first and largest population-based study in Asian patients with lymphoid malignancies treated with L-asp demonstrating that adult patients are at elevated risk of thrombosis after L-asp exposure. The overall incidence of L-asp-related VTE amongst these patients was similar to that in Caucasian populations.

Vitrfication and Slow Freezing for Cryopreservation of Germinal Vesicle-Stage Human Oocytes: A Bayesian Meta-Analysis

BACKGROUND

T he most commonly used methods for the cryopreservation of oocytes and embryos are vitrification and slow freezing.

OBJECTIVE

The aim of this study was to to investigate whether there are differences in survival, in vitro maturation (IVM), and fertilization rates between cryopreserved immature oocytes, especially germinal vesicle (GV)-stage human oocytes, following vitrification and slow freezing.

MATERIALS AND METHODS

A literature search was performed using the MEDLINE, Cochrane Central Register of Controlled Trials, and Embase databases. A total of three studies were included in the Bayesian meta-analysis.

RESULTS

There was no difference in survival rates between vitrification and slow freezing. Additionally, there was no difference in IVM rates and fertilization rates between vitrification and slow freezing.

CONCLUSION

The superiority of vitrification over slow freezing for cryopreservation of GV-stage human oocytes remains unclear. Additional studies on cytoarchitecture and modification of the cryopreservation protocol are essential to achieve strong conclusions.

Serous cystic neoplasm of the pancreas: a multinational study of 2622 patients under the auspices of the International Association of Pancreatology and European Pancreatic Club (European Study Group on Cystic Tumors of the Pancreas)

OBJECTIVES

Serous cystic neoplasm (SCN) is a cystic neoplasm of the pancreas whose natural history is poorly known. The purpose of the study was to attempt to describe the natural history of SCN, including the specific mortality.

DESIGN

Retrospective multinational study including SCN diagnosed between 1990 and 2014.

RESULTS

2622 patients were included. Seventy-four per cent were women, and median age at diagnosis was 58 years (16-99). Patients presented with non-specific abdominal pain (27%), pancreaticobiliary symptoms (9%), diabetes mellitus (5%), other symptoms (4%) and/or were asymptomatic (61%). Fifty-two per cent of patients were operated on during the first year after diagnosis (median size: 40 mm (2-200)), 9% had resection beyond 1 year of follow-up (3 years (1-20), size at diagnosis: 25 mm (4-140)) and 39% had no surgery (3.6 years (1-23), 25.5 mm (1-200)). Surgical indications were (not exclusive) uncertain diagnosis (60%), symptoms (23%), size increase (12%), large size (6%) and adjacent organ compression (5%). In patients followed beyond 1 year (n=1271), size increased in 37% (growth rate: 4 mm/year), was stable in 57% and decreased in 6%. Three serous cystadenocarcinomas were recorded. Postoperative mortality was 0.6% (n=10), and SCN's related mortality was 0.1% (n=1).

CONCLUSIONS

After a 3-year follow-up, clinical relevant symptoms occurred in a very small proportion of patients and size slowly increased in less than half. Surgical treatment should be proposed only for diagnosis remaining uncertain after complete workup, significant and related symptoms or exceptionally when exists concern with malignancy. This study supports an initial conservative management in the majority of patients with SCN.

TRIAL REGISTRATION NUMBER

IRB 00006477.