Traveling Long Distances for Rectal Cancer Care: Institutional Outcomes and Patient Experiences.

INTRODUCTION: Mounting evidence supports traveling to high-volume centers for complex surgical procedures, such as a proctectomy, yet the burden of travel and outcomes of patients traveling long distances is not yet clear. Thus, we aimed to evaluate oncologic outcomes, quality of life, and travel burdens for patients treated for rectal cancer at a single tertiary-care institution. METHODS: A retrospective study of patients treated with proctectomy for locally advanced rectal cancer was performed comparing long and short travel distance (STD) cohorts. Primary outcome measures included overall mortality, disease recurrence, and quality of life. Secondary outcomes included out-of-pocket expenses. The cohorts were compared using Wilcoxon rank-sum and Chi-square tests for continuous and categorical variables, respectively. Kaplan-Meier plots were created to evaluate overall and disease-free survival. RESULTS: Among 102 patients, 51 (50%) were classified as long travel distance (LTD, mean 57.8 miles) and 51 (50%) were classified as STD (mean 12.8 miles). There was no statistical difference in 5-y mortality (4% LTD versus 4% STD, P = 1.000), disease recurrence (26% LTD versus 18% STD, P = 0.336), or quality of life (0.85 LTD versus 0.87 STD, P = 0.690). The LTD cohort did have significantly lower postresection compliance with surveillance (84% LTD versus 96% STD, P = 0.046). LTD cohort also had significantly more lodging ($77.1 LTD versus $0 STD, P = 0.025) and transportation expenses ($133.6 LTD versus $92.6 STD, P = 0.010). CONCLUSIONS: As the surgical management of rectal cancer becomes increasingly centralized, this study found patients who traveled long-distances received comparable care with outcomes similar to those who lived locally. Higher travel costs and lower compliance with surveillance were identified as barriers to care in the long-distance population, but a number of solutions can be implemented to address these issues.

Peptide-mimetic treatment of Pseudomonas aeruginosa in a mouse model of respiratory infection.

The rise of drug resistance has become a global crisis, with >1 million deaths due to resistant bacterial infections each year. Pseudomonas aeruginosa, in particular, remains a serious problem with limited solutions due to complex resistance mechanisms that now lead to more than 32,000 multidrug-resistant (MDR) infections and over 2000 deaths in the U.S. annually. While the emergence of resistant bacteria has become ominously common, identification of useful new drug classes has been limited over the past over 40 years. We found that a potential novel therapeutic, the peptide-mimetic TM5, is effective at killing P. aeruginosa and displays sufficiently low toxicity in mammalian cells to allow for use in treatment of infections. Interestingly, TM5 kills P. aeruginosa more rapidly than traditional antibiotics, within 30-60 min in vitro, and is effective against a range of clinical isolates, including extensively drug resistant strains. In vivo, TM5 significantly reduced bacterial load in the lungs within 24 h compared to untreated mice and demonstrated few adverse effects. Taken together, these observations suggest that TM5 shows promise as an alternative therapy for MDR P. aeruginosa respiratory infections.

Differences in microenvironment of lung cancer and pleural effusions by single-cell RNA sequencing.

BACKGROUND: Direct comparison of tumor microenvironment of matched lung cancer biopsies and pleural effusions (PE) from the same patients is critical in understanding tumor biology but has not been performed. This is the first study to compare the lung cancer and PE microenvironment by single-cell RNA sequencing (scRNA-seq). METHODS: Matched lung cancer biopsies and PE were obtained prospectively from ten patients. We isolated CD45+ cells and performed scRNA-seq to compare the biopsies and PE. RESULTS: PE had a higher proportion of CD4+ T cells but lower proportion of CD8+ T cells (False detection rate, FDR = 0.0003) compared to biopsies. There was a higher proportion of naïve CD4+ T cells (FDR = 0.04) and naïve CD8+ T cells (FDR = 0.0008) in PE vs. biopsies. On the other hand, there was a higher proportion of Tregs (FDR = 0.04), effector CD8+ (FDR = 0.006), and exhausted CD8+ T cells (FDR = 0.01) in biopsies. The expression of inflammatory genes in T cells was increased in biopsies vs. PE, including TNF, IFN-É£, IL-1R1, IL-1R2, IL-2, IL-12RB2, IL-18R1, and IL-18RAP (FDR = 0.009, 0.013, 0.029, 0.043, 0.009, 0.013, 0.004, and 0.003, respectively). The gene expression of exhaustion markers in T cells was also increased in tumor biopsies including PDCD1, CTLA4, LAG 3, HAVCR2, TIGIT, and CD160 (FDR = 0.008, 0.003, 0.002, 0.011, 0.006, and 0.049, respectively). CONCLUSIONS: There is a higher proportion of naïve T cells and lower proportion of exhausted T cells and Tregs in PE compared to lung cancer biopsies, which can be leveraged for prognostic and therapeutic applications.

Applying Multimodal Mass Spectrometry to Image Tumors Undergoing Ferroptosis Following In Vivo Treatment with a Ferroptosis Inducer.

Epithelial ovarian cancer (EOC) is the most common form of ovarian cancer. The poor prognosis generally associated with this disease has led to the search for improved therapies such as ferroptosis-inducing agents. Ferroptosis is a form of regulated cell death that is dependent on iron and is characterized by lipid peroxidation. Precise mapping of lipids and iron within tumors exposed to ferroptosis-inducing agents may provide insight into processes of ferroptosis in vivo and ultimately assist in the optimal deployment of ferroptosis inducers in cancer therapy. In this work, we present a method for combining matrix-assisted laser desorption/ionization (MALDI) mass spectrometry imaging (MSI) with secondary ion mass spectrometry (SIMS) to analyze changes in spatial lipidomics and metal composition, respectively, in ovarian tumors following exposure to a ferroptosis inducer. Tumors were obtained by injecting human ovarian cancer tumor-initiating cells into mice, followed by treatment with the ferroptosis inducer erastin. SIMS imaging detected iron accumulation in the tumor tissue, and sequential MALDI-MS imaging of the same tissue section displayed two chemically distinct regions of lipids. One region was associated with the iron-rich area detected with SIMS, and the other region encompassed the remainder of the tissue section. Bulk lipidomics confirmed the lipid assignments putatively assigned from the MALDI-MS data. Overall, we demonstrate the ability of multimodal MSI to identify the spatial locations of iron and lipids in the same tissue section and associate these regions with clinical pathology.

Evaluation of the Rothman Index in Predicting Readmission after Colorectal Resection.

The Rothman Index (RI) is a real-time health indicator score that has been used to quantify readmission risk in several fields but has never been studied in gastrointestinal surgery. In this retrospective single-institution study, the association between RI scores and readmissions after unplanned colectomy or proctectomy was evaluated in 427 inpatients. Patient demographics and perioperative measures, including last RI, lowest RI, and increasing/decreasing RI score, were collected. In the selected cohort, 12.4% of patients were readmitted within 30 days of their initial discharge. Last RI, lowest RI, decreasing RI, and increasing RI scores remained significant after controlling for covariates in separate multivariate regression analyses. The last RI score at the time of discharge was found to be the most strongly associated with 30-day readmission risk following colorectal resection. These findings support the RI as a potential tool in the inpatient management of postoperative patients to identify those at high risk of readmission.

Evaluation of host cellular responses to Epstein-Barr virus (EBV) in adult lung transplant patients with EBV-associated diseases.

Epstein-Barr virus (EBV) reactivation is commonly observed in lung transplant recipients (LTRs). However, cellular immune responses to EBV in adult LTRs have not been well described. We aimed to study CD4/CD8 ratio, EBV-specific T cells polyfunctional responses and phenotypic changes in natural killer (NK) cells in adult LTRs presenting with EBV-associated diseases. The CD4/CD8 ratio was significantly decreased in LTRs with EBV DNAemia compared with LTRs without EBV DNAemia and healthy controls (HCs). Stimulation with EBV lytic antigen BZLF1 peptide pools induced significant individual and polyfunctional responses from CD8+ CD69+ T cells. Frequencies of CD8+ CD69+ T cells expressing CD107a were significantly higher in LTRs without EBV DNAemia than in LTRs with DNAemia. Frequencies of CD8+ CD69+ T cells concurrently expressing CD107a, IFN-γ, and TNF-α were significantly greater in LTRs with and without EBV DNAemia than in HCs. Finally, BZLF1 induced significantly higher frequencies of CD8+ CD69+ T cells expressing CD107a and IFN-γ in LTRs without EBV DNAemia when compared with EBNA3B. Frequency of more differentiated CD56dim CD16pos NK cells was significantly decreased in LTRs with EBV DNAemia and PTLD compared with HCs. In conclusion, we noted the presence of significant changes in circulating cellular immune responses to EBV in adult LTRs.

Predicting Neoadjuvant Treatment Response in Rectal Cancer Using Machine Learning: Evaluation of MRI-Based Radiomic and Clinical Models.

BACKGROUND: Radiomics is an approach to medical imaging that quantifies the features normally translated into visual display. While both radiomic and clinical markers have shown promise in predicting response to neoadjuvant chemoradiation therapy (nCRT) for rectal cancer, the interrelationship is not yet clear. METHODS: A retrospective, single-institution study of patients treated with nCRT for locally advanced rectal cancer was performed. Clinical and radiomic features were extracted from electronic medical record and pre-treatment magnetic resonance imaging, respectively. Machine learning models were created and assessed for complete response and positive treatment effect using the area under the receiver operating curves. RESULTS: Of 131 rectal cancer patients evaluated, 68 (51.9%) were identified to have a positive treatment effect and 35 (26.7%) had a complete response. On univariate analysis, clinical T-stage (OR 0.46, p = 0.02), lymphovascular/perineural invasion (OR 0.11, p = 0.03), and statin use (OR 2.45, p = 0.049) were associated with a complete response. Clinical T-stage (OR 0.37, p = 0.01), lymphovascular/perineural invasion (OR 0.16, p = 0.001), and abnormal carcinoembryonic antigen level (OR 0.28, p = 0.002) were significantly associated with a positive treatment effect. The clinical model was the strongest individual predictor of both positive treatment effect (AUC = 0.64) and complete response (AUC = 0.69). The predictive ability of a positive treatment effect increased by adding tumor and mesorectal radiomic features to the clinical model (AUC = 0.73). CONCLUSIONS: The use of a combined model with both clinical and radiomic features resulted in the strongest predictive capability. With the eventual goal of tailoring treatment to the individual, both clinical and radiologic markers offer insight into identifying patients likely to respond favorably to nCRT.

Intracranial fungal Cladophialophora bantiana infection in a nonimmunocompromised patient: A case report and review of the literature.

Background: Cladophialophora bantiana is a dematiaceous fungus that rarely infects the central nervous system (CNS). It is associated with a mortality rate of over 70% despite treatment. Case Description: An 81-year-old female with a remote history of renal cell carcinoma presented with progressive headache and an expressive aphasia for 3 days. Computed tomography imaging revealed a left frontotemporal mass with surrounding vasogenic edema. A left frontotemporal craniotomy was performed and cultures revealed C. bantiana. The initial management with IV voriconazole was unsuccessful and the patient had a recurrence of the cranial infection and developed pulmonary abscesses. Following the addition of oral flucytosine, the patient showed a significant improvement with a complete radiographic resolution of both the cranial and pulmonary lesions. Conclusion: C. bantiana involving the CNS is a rare and often fatal disease. Surgical management along with standard antifungal treatment may not provide definitive therapy. The addition of flucytosine to IV voriconazole resulted in a positive outcome for this patient who is alive, living independently 1 year from the original diagnosis. In this rare fungal infection, standard antifungal treatment may not provide adequate coverage and the utilization of additional therapy may be required.

Evaluation and Management of Lower GI Bleeding.

CASE SUMMARY: A 73-year-old woman, who had received apixaban for therapeutic anticoagulation, presented with hypotension and hematochezia. After resuscitation, diagnostic colonoscopy revealed multiple polyps and old blood within the colonic lumen, but no active bleeding (Fig. 1). Nasogastric lavage and subsequent EGD were unremarkable. During her hospitalization, she was admitted to the intensive care unit with worsening anemia, hypotension, and hematochezia. CT angiogram showed extravasation at the transverse colon (Fig. 1). Formal angiogram was unable to localize the source of bleeding, despite provocation. Given the localization on CT angiography and the patient's clinical deterioration, she underwent hand-assisted segmental transverse colectomy. Surgical pathology was notable for multiple adenomas without dysplasia. The patient had no further episodes of GI bleeding after resection.

A phase 2 trial of avelumab in men with aggressive-variant or neuroendocrine prostate cancer.

BACKGROUND: Men with progressive neuroendocrine or aggressive-variant metastatic prostate cancer (NEPC/AVPC) have a poor prognosis and limited treatment options, and immunotherapy has not been tested in such patients. METHODS: We conducted an open label single center phase 2 trial (NCT03179410) of men with progressive NEPC/AVPC either defined by histology or AVPC criteria. Avelumab (10 mg/kg every 2 weeks) was administered until progression or unacceptable toxicity. The primary endpoint was overall response rate (ORR). Secondary endpoints included ORR, radiographic progression-free survival (rPFS), overall survival, and safety. Correlative studies included longitudinal peripheral blood immune phenotyping. The study was limited by the small number of patients enrolled and by the early termination due to COVID-19. RESULTS: A total of 15 men with AVPC/NEPC were enrolled. The median age was 71 (range 51-85 years), and men had received a median of two prior therapies (range 1-3). Median PSA was 54 ng/dl (range 0-393), and 73% of men had liver metastasis. The ORR with avelumab in this setting by iRECIST or RECIST 1.1 was 6.7%, including one patient (6.7%) with a complete remission (CR), 20% with stable disease, and 67% with progressive disease. The patient with the CR had an MSH2 somatic mutation and MSI-high NEPC with central nervous system metastases, and his CR remains durable off all therapy for 2 years. The median rPFS was 1.8 months (95% CI 1.6-3.6 months), and median overall survival was 7.4 months (85% CI 2.8-12.6 months). Safety was consistent with the known profile of avelumab. Phenotyping of peripheral immune subsets suggest enhanced CXCR2-dependent myeloid and T-cell responses in this extraordinary responder. CONCLUSIONS: While the study was terminated early due to slow enrollment at the onset of the COVID-19 pandemic and lower than anticipated objective response rate, PD-L1 inhibition with avelumab monotherapy showed poor efficacy in patients with microsatellite stable NEPC/AVPC. Immune profiling revealed enhanced CXCR2 positive immune cell activation in the one extraordinary responder, suggesting potential mechanisms for further immunotherapy development in this population.

Wnt activation promotes memory T cell polyfunctionality via epigenetic regulator PRMT1.

T cell polyfunctionality is a hallmark of protective immunity against pathogens and cancer, yet the molecular mechanism governing it remains mostly elusive. We found that canonical Wnt agonists inhibited human memory CD8+ T cell differentiation while simultaneously promoting the generation of highly polyfunctional cells. Downstream effects of Wnt activation persisted after removal of the drug, and T cells remained polyfunctional following subsequent cell division, indicating the effect is epigenetically regulated. Wnt activation induced a gene expression pattern that is enriched with stem cell-specific gene signatures and upregulation of protein arginine methyltransferase 1 (PRMT1), a known epigenetic regulator. PRMT1+CD8+ T cells are associated with enhanced polyfunctionality, especially the ability to produce IL-2. In contrast, inhibition of PRMT1 ameliorated the effects of Wnt on polyfunctionality. Chromatin immunoprecipitation revealed that H4R3me2a, a permissive transcription marker mediated by PRMT1, increased at the IL-2 promoter loci following Wnt activation. In vivo, Wnt-treated T cells exhibited superior polyfunctionality and persistence. When applied to cytomegalovirus (CMV) donor-seropositive, recipient-seronegative patients (D+/R-) lung transplant patient samples, Wnt activation enhanced CMV-specific T cell polyfunctionality, which is important in controlling CMV diseases. These findings reveal a molecular mechanism governing T cell polyfunctionality and identify PRMT1 as a potential target for T cell immunotherapy.

Disseminated Histoplasmosis: An Unusual Cause of Bowel Obstruction.

INTRODUCTION: Although histoplasmosis is an extremely rare cause of bowel obstruction, this case describes disseminated gastrointestinal histoplasmosis as it progresses from acute colitis to subacute recurrent bowel obstructions. CASE PRESENTATION: A White man in his early 80s with history of multiple myeloma presented to the emergency department with lightheadedness and diarrhea. Following a diagnostic journey for unspecified colitis, urine antigen testing and endoscopic biopsies led to the diagnosis. During the initial 12 weeks of antifungal treatment, the disease process transitioned from an acute inflammatory syndrome into a recurrent bowel obstruction. DISCUSSION/CONCLUSIONS: Only one other case of histoplasmosis causing recurrent bowel obstruction has been reported; however, that patient succumbed to the disease without surgical intervention. No clear guidelines exist of how to manage bowel obstructions from rare infectious sources, such as histoplasmosis, but close surveillance, multidisciplinary care, and an understanding of gastrointestinal pathology can guide clinicians when encountering atypical etiologies of bowel obstruction.

Saddle block anesthetic technique for benign outpatient anorectal surgery.

BACKGROUND: Current American Society of Colorectal Surgery Clinical Practice Guidelines for Ambulatory Anorectal Surgery endorse use of monitored anesthesia care, general anesthesia, or spinal anesthesia based on physician and patient preference. Although several studies support the use of monitored anesthesia care over general anesthesia, the literature regarding spinal anesthesia is limited and heterogenous due to small sample sizes and disparate spinal anesthesia techniques. Saddle block anesthesia is a form of spinal anesthesia that localizes to the lowermost sacral spinal segments allowing for preservation of lower extremity motor function and faster recovery. We accrued one of the largest reported cohort of anorectal procedures using saddle block anesthesia, as such, we sought to evaluate our institutional 12-year experience. METHODS: Patients who underwent a benign anorectal procedure at our outpatient surgery center between July 2008-2020 were retrospectively reviewed. Demographics, surgical factors, perioperative times, and adverse events were collected from the electronic medical records. Saddle block anesthesia was generally performed in the preoperative area using a spinal needle (25-27 gauge) and a single injection technique of a 1:1 ratio local anesthetic mixed with 10% dextrose solution. Between 2.5-5 mg of hyperbaric anesthetic was injected intrathecally in the sitting position and the patient remained upright for 3-10 minutes. This technique of saddle block anesthesia provides analgesia for approximately 1-3 hours. RESULTS: In the study, 859 saddle block anesthesia patients were identified, with a mean age of 44.6 years and American Society of Anesthesia score of 1.9; 609 (70.9%) were male. Surgical indications included lesion removal (27.1%), anal fistula (25.8%), hemorrhoidectomy (24.7%), pilonidal disease (6.3%), anal fissure (5.8%), and a combination of prior (10.2%). Prone jackknife positioning was used in 91.6% of procedures. Saddle block anesthesia most often was performed with bupivacaine (48.9%) or ropivacaine (41.7%). The median procedural saddle block anesthesia time was 11 minutes, surgery time was 17 minutes, anesthesia time was 42 minutes, and recovery time was 91 minutes. Patients spent a median of 3 hours and 53 minutes in the facility. Adverse events included urinary retention (1.9%), conversion to general anesthesia (1.8%), spinal headache (1.5%), hemodynamic instability (0.9%), and injection site reaction (0.3%). CONCLUSION: Demonstrated using the largest known cohort of anorectal patients with saddle block anesthesia, saddle block anesthesia provides an effective method of analgesia to avoid general anesthesia with a low rate of adverse events.

Physiological Fitness and the Pathophysiology of Chronic Lymphocytic Leukemia (CLL).

Chronic lymphocytic leukemia (CLL) is associated with physical dysfunction and low overall fitness that predicts poor survival following the commencement of treatment. However, it remains unknown whether higher fitness provides antioncogenic effects. We identified ten fit (CLL-FIT) and ten less fit (CLL-UNFIT) treatment-naïve CLL patients from 144 patients who completed a set of physical fitness and performance tests. Patient plasma was used to determine its effects on an in vitro 5-day growth/viability of three B-cell cell lines (OSU-CLL, Daudi, and Farage). Plasma exosomal miRNA profiles, circulating lipids, lipoproteins, inflammation levels, and immune cell phenotypes were also assessed. CLL-FIT was associated with fewer viable OSU-CLL cells at Day 1 (p = 0.003), Day 4 (p = 0.001), and Day 5 (p = 0.009). No differences between the groups were observed for Daudi and Farage cells. Of 455 distinct exosomal miRNAs identified, 32 miRNAs were significantly different between the groups. Of these, 14 miRNAs had ≤-1 or ≥1 log2 fold differences. CLL-FIT patients had five exosomal miRNAs with lower expression and nine miRNAs with higher expression. CLL-FIT patients had higher HDL cholesterol, lower inflammation, and lower levels of triglyceride components (all p < 0.05). CLL-FIT patients had lower frequencies of low-differentiated NKG2+/CD158a/bneg (p = 0.015 and p = 0.014) and higher frequencies of NKG2Aneg/CD158b+ mature NK cells (p = 0.047). The absolute number of lymphocytes, including CD19+/CD5+ CLL-cells, was similar between the groups (p = 0.359). Higher physical fitness in CLL patients is associated with altered CLL-like cell line growth in vitro and with altered circulating and cellular factors indicative of better immune functions and tumor control.

Ceramide synthase 2 deletion decreases the infectivity of HIV-1.

The lipid composition of HIV-1 virions is enriched in sphingomyelin (SM), but the roles that SM or other sphingolipids (SLs) might play in the HIV-1 replication pathway have not been elucidated. In human cells, SL levels are regulated by ceramide synthase (CerS) enzymes that produce ceramides, which can be converted to SMs, hexosylceramides, and other SLs. In many cell types, CerS2, which catalyzes the synthesis of very long chain ceramides, is the major CerS. We have examined how CerS2 deficiency affects the assembly and infectivity of HIV-1. As expected, we observed that very long chain ceramide, hexosylceramide, and SM were reduced in CerS2 knockout cells. CerS2 deficiency did not affect HIV-1 assembly or the incorporation of the HIV-1 envelope (Env) protein into virus particles, but it reduced the infectivites of viruses produced in the CerS2-deficient cells. The reduced viral infection levels were dependent on HIV-1 Env, since HIV-1 particles that were pseudotyped with the vesicular stomatitis virus glycoprotein did not exhibit reductions in infectivity. Moreover, cell-cell fusion assays demonstrated that the functional defect of HIV-1 Env in CerS2-deficient cells was independent of other viral proteins. Overall, our results indicate that the altered lipid composition of CerS2-deficient cells specifically inhibit the HIV-1 Env receptor binding and/or fusion processes.

Clinical Impact of Antecedent Bariatric Surgery on Liver Transplant Outcomes: A Retrospective Matched Case-control Study.

BACKGROUND: Bariatric surgery (BS) may be associated with significant malabsorption and nutritional deficiencies. METHODS: Between March 1987 and January 2017, we performed 922 liver transplants (LT) at our institution; 33 had antecedent BS. We matched the BS cohort to LT recipients without BS (1:3 matching) based on exact matching for gender and cancer and inverse variance matching for age, LT body mass index, MELD score, and transplant date. RESULTS: We analyzed outcomes in 132 LT recipients (33 BS; 99 non-BS). The BS cohort comprised 26 (79%) women with a mean age of 52.4 years. The BS procedures included 20 Roux-en-Y gastric bypass (61%), 6 jejunoileal bypass (18%), 3 gastric band (9%), 2 sleeve gastrectomy (6%), and 1 duodenal switch (3%). The primary indications for LT listing were alcoholic cirrhosis (9; 27%), nonalcoholic steatohepatitis (7; 21%), hepatitis C (8; 24%), and hepatocellular carcinoma (3; 9%). At LT, body mass index for the BS cohort was 29.6, and MELD was 24. Compared with matched controls, BS recipients did not have longer LT length of hospital stay (17.8 versus 15.7 d, P = 0.71), longer intensive care unit length of stay (5.3 versus 4.1 d, P = 0.16), or higher 30-day complication rate (76% versus 85%, P = 0.43). Overall patient survival was similar (1- and 3-y survival was 90.1% and 75.9% for BS; 90.9% and 76.4% for non-BS, P = 0.34). CONCLUSIONS: A history of BS does not portend a deleterious effect on LT outcomes.

Ipilimumab and Radiation in Patients with High-risk Resected or Regionally Advanced Melanoma.

PURPOSE: In this prospective trial, we sought to assess the feasibility of concurrent administration of ipilimumab and radiation as adjuvant, neoadjuvant, or definitive therapy in patients with regionally advanced melanoma. PATIENTS AND METHODS: Twenty-four patients in two cohorts were enrolled and received ipilimumab at 3 mg/kg every 3 weeks for four doses in conjunction with radiation; median dose was 4,000 cGy (interquartile range, 3,550-4,800 cGy). Patients in cohort 1 were treated adjuvantly; patients in cohort 2 were treated either neoadjuvantly or as definitive therapy. RESULTS: Adverse event profiles were consistent with those previously reported with checkpoint inhibition and radiation. For the neoadjuvant/definitive cohort, the objective response rate was 64% (80% confidence interval, 40%-83%), with 4 of 10 evaluable patients achieving a radiographic complete response. An additional 3 patients in this cohort had a partial response and went on to surgical resection. With 2 years of follow-up, the 6-, 12-, and 24-month relapse-free survival for the adjuvant cohort was 85%, 69%, and 62%, respectively. At 2 years, all patients in the neoadjuvant/definitive cohort and 10/13 patients in the adjuvant cohort were still alive. Correlative studies suggested that response in some patients were associated with specific CD4+ T-cell subsets. CONCLUSIONS: Overall, concurrent administration of ipilimumab and radiation was feasible, and resulted in a high response rate, converting some patients with unresectable disease into surgical candidates. Additional studies to investigate the combination of radiation and checkpoint inhibitor therapy are warranted.

Assessing Collision Cross Section Calibration Strategies for Traveling Wave-Based Ion Mobility Separations in Structures for Lossless Ion Manipulations.

The collision cross section (CCS) is an important property that aids in the structural characterization of molecules. Here, we investigated the CCS calibration accuracy with traveling wave ion mobility spectrometry (TWIMS) separations in structures for lossless ion manipulations (SLIM) using three sets of calibrants. A series of singly negatively charged phospholipids and bile acids were calibrated in nitrogen buffer gas using two different TW waveform profiles (square and sine) and amplitudes (20, 25, and 30 V0-p). The calibration errors for the three calibrant sets (Agilent tuning mixture, polyalanine, and one assembled in-house) showed negligible differences using a sine-shaped TW waveform. Calibration errors were all within 1-2% of the drift tube ion mobility spectrometry (DTIMS) measurements, with lower errors for sine waveforms, presumably due to the lower average and maximum fields experienced by ions. Finally, ultrahigh-resolution multipass (long path length) SLIM TWIMS separations demonstrated improved CCS calibration for phospholipid and bile acid isomers.

A randomized phase 2 trial of pembrolizumab versus pembrolizumab and acalabrutinib in patients with platinum-resistant metastatic urothelial cancer.

BACKGROUND: Inhibition of the programmed cell death protein 1 (PD-1) pathway has demonstrated clinical benefit in metastatic urothelial cancer (mUC); however, response rates of 15% to 26% highlight the need for more effective therapies. Bruton tyrosine kinase (BTK) inhibition may suppress myeloid-derived suppressor cells (MDSCs) and improve T-cell activation. METHODS: The Randomized Phase 2 Trial of Acalabrutinib and Pembrolizumab Immunotherapy Dual Checkpoint Inhibition in Platinum-Resistant Metastatic Urothelial Carcinoma (RAPID CHECK; also known as ACE-ST-005) was a randomized phase 2 trial evaluating the PD-1 inhibitor pembrolizumab with or without the BTK inhibitor acalabrutinib for patients with platinum-refractory mUC. The primary objectives were safety and objective response rates (ORRs) according to the Response Evaluation Criteria in Solid Tumors, version 1.1. Secondary endpoints included progression-free survival (PFS) and overall survival (OS). Immune profiling was performed to analyze circulating monocytic MDSCs and T cells. RESULTS: Seventy-five patients were treated with pembrolizumab (n = 35) or pembrolizumab plus acalabrutinib (n = 40). The ORR was 26% with pembrolizumab (9% with a complete response [CR]) and 20% with pembrolizumab plus acalabrutinib (10% with a CR). The grade 3/4 adverse events (AEs) that occurred in ≥15% of the patients were anemia (20%) with pembrolizumab and fatigue (23%), increased alanine aminotransferase (23%), urinary tract infections (18%), and anemia (18%) with pembrolizumab plus acalabrutinib. One patient treated with pembrolizumab plus acalabrutinib had high MDSCs at the baseline, which significantly decreased at week 7. Overall, MDSCs were not correlated with a clinical response, but some subsets of CD8+ T cells did increase during the combination treatment. CONCLUSIONS: Both treatments were generally well tolerated, although serious AE rates were higher with the combination. Acalabrutinib plus pembrolizumab did not improve the ORR, PFS, or OS in comparison with pembrolizumab alone in mUC. Baseline and on-treatment peripheral monocytic MDSCs were not different in the treatment cohorts. Proliferating CD8+ T-cell subsets increased during treatment, particularly in the combination cohort. Ongoing studies are correlating these peripheral immunome findings with tissue-based immune cell infiltration.