Improved characterization and translation of NK cells for canine immunotherapy.

The field of cancer immunology has seen a meteoric rise in interest and application due to the discovery of immunotherapies that target immune cells, often leading to dramatic anti-tumor effects. However, successful cellular immunotherapy for solid tumors remains a challenge, and the application of immunotherapy to dogs with naturally occurring cancers has emerged as a high yield large animal model to bridge the bench-to-bedside challenges of immunotherapies, including those based on natural killer (NK) cells. Here, we review recent developments in the characterization and understanding of canine NK cells, a critical springboard for future translational NK immunotherapy research. The characterization of canine NK cells is exceptionally pertinent given the ongoing challenges in defining them and contextualizing their similarities and differences compared to human and murine NK cells compounded by the limited availability of validated canine specific reagents. Additionally, we summarize the current landscape of the clinical and translational literature employing strategies to capitalize on endogenous and exogenous NK cell immunotherapy in canine cancer patients. The insights regarding efficacy and immune correlates from these trials provide a solid foundation to design and test novel combinational therapies to enhance NK cell activity with the added benefit of motivating comparative work to translate these findings to human cancers with extensive similarities to their canine counterparts. The compilation of knowledge from basic canine NK phenotype and function to applications in first-in-dog clinical trials will support the canine cancer model and enhance translational work to improve cancer outcomes for both dogs and humans.

Missing a "Missing Self" Mechanism: Modeling and Detection of Ly49 Expression in Canine NK Cells.

NK cells are a key focus in immuno-oncology, based on their ability to eliminate malignant cells without prior sensitization. Dogs are valuable models for translational immunotherapy studies, especially for NK cells, where critical species differences exist between mice and humans. Given that the mechanism for recognition of "self" by canine NK cells is currently unknown, we sought to evaluate expression of Ly49 in canine NK cells using in silico and high-throughput techniques. We interrogated the identified polymorphism/mutation in canine Ly49 and assessed the potential impact on structure using computational modeling of three-dimensional protein structure and protein-protein docking of canine Ly49 with MHC class I (MHC-I). Bulk and single-cell RNA-sequencing analysis was performed to detect gene expression of Ly49/KLRA1 in resting and activated NK cells. Tertiary protein structure demonstrated significant structural similarity to the known murine system. Molecular docking of canine Ly49 with MHC-I was favorable, converging at a single low-energy conformation. RNA sequencing revealed expression of Ly49/KLRA1 in both resting and activated NK cells and demonstrated almost exclusive expression of the gene in the NK cluster at the single-cell level. Despite prior reports of a mutated, nonfunctional canine Ly49, our data support that the protein product is predicted to bind to MHC-I in a comparable conformation to the murine system and is expressed in canine NK cells with upregulation following activation. Taken together, these data suggest that Ly49 is capable of recognizing MHC-I and therefore regulating NK cell function in dogs.

Intratumoral NKp46+ natural killer cells are spatially distanced from T and MHC-I+ cells with prognostic implications in soft tissue sarcoma.

Introduction: Soft tissue sarcomas (STS) are rare, heterogenous malignancies with an unmet need for novel immunotherapies. Tumor infiltrating lymphocytes (TILs) have been linked with favorable outcomes in STS patients, though the contribution of natural killer (NK) cells and spatial relationships of TILs with MHC-I expressing cells lacks detailed characterization. Experimental design: Using archived and prospectively collected specimens, we evaluated intratumoral NK cells by immunohistochemistry (IHC), flow cytometry, and immunofluorescence (IF). We assessed spatial localization of NK and T cells by multiplex IF, analyzing the effects of MHC-I expression status on NK and T cell clustering. Results: Both intratumoral NKp46 and CD56dim expression were associated with significantly improved overall survival (P=0.05), while higher infiltrates of CD56bright NK cells predicted a worse prognosis (P=0.05). The presence of intratumoral NK cells was inversely proportional to CD3+ T cells. Spatial analyses showed NK cells preferentially clustering close to other NK cells with sparse CD3+ T and CD8+ T cells in range (P<0.0001). Additionally, CD3+ T and CD8+ T cells showed significantly greater co-localization with MHC-I+ cells, compared to NK cells (P<0.0001). After neoadjuvant radiotherapy, there was greater CD8 clustering, while after neoadjuvant chemotherapy, there was overall lower TIL clustering. Conclusion: Intratumoral NK cells are prognostic in STS and localize closer to MHC-I- cells than T cells. Although both NK and T cells are associated with improved survival in STS, their differential distribution in the TME based on MHC-I expression status may serve as a biomarker for improved immunotherapy treatment selection.

The Landscape of Immunotherapy for Retroperitoneal Sarcoma.

Significant multidisciplinary scientific effort has been undertaken to understand the heterogeneous family of neoplasms that comprise soft tissue sarcomas. Within this family of neoplasms, outcomes for retroperitoneal sarcomas (RPS) are currently limited given a lack of effective therapies. In this review, we focus on immunotherapy and its relationship with the common RPS histologic subtypes. Although initial outcomes for RPS patients with immune checkpoint inhibition alone have been somewhat disappointing, subsequent analyses on histologies, the tumor microenvironment, sarcoma immune class, tumor infiltrating lymphocytes and genetic analysis for tumor mutational burden have yielded insight into the interplay between sarcomas and immunotherapy. Such approaches have all provided critical insight into the environment and characterization of these tumors, with targets for potential immunotherapy in future clinical trials. With this insight, molecularly tailored combination treatments for improving response rates and oncologic outcomes for RPS are promising.

Human soft tissue sarcomas harbor an intratumoral viral microbiome which is linked with natural killer cell infiltrate and prognosis.

BACKGROUND: Groundbreaking studies have linked the gut microbiome with immune homeostasis and antitumor immune responses. Mounting evidence has also demonstrated an intratumoral microbiome, including in soft tissue sarcomas (STS), although detailed characterization of the STS intratumoral microbiome is limited. We sought to characterize the intratumoral microbiome in patients with STS undergoing preoperative radiotherapy and surgery, hypothesizing the presence of a distinct intratumoral microbiome with potentially clinically significant microbial signatures. METHODS: We prospectively obtained tumor and stool samples from adult patients with non-metastatic STS using a strict sterile collection protocol to minimize contamination. Metagenomic classification was used to estimate abundance using genus and species taxonomic levels across all classified organisms, and data were analyzed with respect to clinicopathologic factors. RESULTS: Fifteen patients were enrolled. Most tumors were located at an extremity (67%) and were histologic grade 3 (87%). 40% were well-differentiated/dedifferentiated liposarcoma histology. With a median follow-up of 24 months, 4 (27%) patients developed metastases, and 3 (20%) died. Despite overwhelming human DNA (>99%) intratumorally, we detected a small but consistent proportion of bacterial DNA (0.02-0.03%) in all tumors, including Proteobacteria, Bacteroidetes, and Firmicutes, as well as viral species. In the tumor microenvironment, we observed a strong positive correlation between viral relative abundance and natural killer (NK) infiltration, and higher NK infiltration was associated with superior metastasis-free and overall survival by immunohistochemical, flow cytometry, and multiplex immunofluorescence analyses. CONCLUSIONS: We prospectively demonstrate the presence of a distinct and measurable intratumoral microbiome in patients with STS at multiple time points. Our data suggest that the STS tumor microbiome has prognostic significance with viral relative abundance associated with NK infiltration and oncologic outcome. Additional studies are warranted to further assess the clinical impact of these findings.

Inhaled recombinant human IL-15 in dogs with naturally occurring pulmonary metastases from osteosarcoma or melanoma: a phase 1 study of clinical activity and correlates of response.

PURPOSE: Although recombinant human interleukin-15 (rhIL-15) has generated much excitement as an immunotherapeutic agent for cancer, activity in human clinical trials has been modest to date, in part due to the risks of toxicity with significant dose escalation. Since pulmonary metastases are a major site of distant failure in human and dog cancers, we sought to investigate inhaled rhIL-15 in dogs with naturally occurring lung metastases from osteosarcoma (OSA) or melanoma. We hypothesized a favorable benefit/risk profile given the concentrated delivery to the lungs with decreased systemic exposure. EXPERIMENTAL DESIGN: We performed a phase I trial of inhaled rhIL-15 in dogs with gross pulmonary metastases using a traditional 3+3 cohort design. A starting dose of 10 µg twice daily × 14 days was used based on human, non-human primate, and murine studies. Safety, dose-limiting toxicities (DLT), and maximum tolerated dose (MTD) were the primary objectives, while response rates, progression-free and overall survival (OS), and pharmacokinetic and immune correlative analyses were secondary. RESULTS: From October 2018 to December 2020, we enrolled 21 dogs with 18 dogs reaching the 28-day response assessment to be evaluable. At dose level 5 (70 µg), we observed two DLTs, thereby establishing 50 µg twice daily × 14 days as the MTD and recommended phase 2 dose. Among 18 evaluable dogs, we observed one complete response >1 year, one partial response with resolution of multiple target lesions, and five stable disease for an overall clinical benefit rate of 39%. Plasma rhIL-15 quantitation revealed detectable and sustained rhIL-15 concentrations between 1-hour and 6 hour postnebulization. Decreased pretreatment lymphocyte counts were significantly associated with clinical benefit. Cytotoxicity assays of banked peripheral blood mononuclear cells revealed significant increases in peak cytotoxicity against canine melanoma and OSA targets that correlated with OS. CONCLUSIONS: In this first-in-dog clinical trial of inhaled rhIL-15 in dogs with advanced metastatic disease, we observed promising clinical activity when administered as a monotherapy for only 14 days. These data have significant clinical and biological implications for both dogs and humans with refractory lung metastases and support exploration of combinatorial therapies using inhaled rhIL-15.

Child-rearing During Postgraduate Medical Training and Its Relation to Stress and Burnout: Results From a Single-institution Multispecialty Survey.

INTRODUCTION: Child-rearing is difficult for medical trainees, but much of the available evidence is limited to individual specialties or lacks an analysis of well-being. In light of this, we sought to examine current perspectives across a wide range of medical specialties, determine associations with stress and burnout, and identify potential supportive solutions. METHODS: After Institutional Review Board approval, a voluntary and anonymous survey was sent to all residents and fellows at a large academic medical center with a U.S. Air Force joint training agreement in 2019. Frequency tables were generated for survey responses, using χ2 test for analysis between groups. RESULTS: One hundred and eighty-four physician trainees completed the survey (21.6% response rate), of which 38.0% were parents. Overall, 90.8% of trainees want children but 68.5% plan to wait until after training to start or grow their families, mainly due to insufficient time or inadequate child care. Less than 2% cited lack of program support as the reason. Among trainee parents, 72.0% reported that child care was at least quite stressful. Child care contributes to burnout for 68.6% of trainee parents, and there was no difference between medical and surgical trainees or between military and nonmilitary trainees. Day care was the most common primary child care strategy, and 37.1% of trainee parents reported spending >25% of their household income on child care. Proposed helpful solutions include on-site day care and subsidies. CONCLUSIONS: Most medical trainees in this sample want children, yet many are delaying growing their families due to time and financial constraints. For trainee parents, child care causes stress and family and financial strain and contributes to burnout. Physicians in training, including military members training at civilian medical centers, could benefit from child care assistance in order to relieve stress, reduce burnout, and improve well-being. Furthermore, by expanding existing resources and implementing new creative solutions to the challenges of child-rearing among medical professionals, the U.S. military has an opportunity to improve members' well-being and be a model to civilian graduate medical education programs nationwide.

Natural Killer and T Cell Infiltration in Canine Osteosarcoma: Clinical Implications and Translational Relevance.

Metastatic osteosarcoma has a bleak prognosis in both humans and dogs, and there have been minimal therapeutic advances in recent decades to improve outcomes. Naturally occurring osteosarcoma in dogs is shown to be a highly suitable model for human osteosarcoma, and limited data suggest the similarities between species extend into immune responses to cancer. Studies show that immune infiltrates in canine osteosarcoma resemble those of human osteosarcoma, and the analysis of tumor immune constituents as predictors of therapeutic response is a promising direction for future research. Additionally, clinical studies in dogs have piloted the use of NK transfer to treat osteosarcoma and can serve as valuable precursors to clinical trials in humans. Cytotoxic lymphocytes in dogs and humans with osteosarcoma have increased activation and exhaustion markers within tumors compared with blood. Accordingly, NK and T cells have complex interactions among cancer cells and other immune cells, which can lead to changes in pathways that work both for and against the tumor. Studies focused on NK and T cell interactions within the tumor microenvironment can open the door to targeted therapies, such as checkpoint inhibitors. Specifically, PD-1/PD-L1 checkpoint expression is conserved across tumors in both species, but further characterization of PD-L1 in canine osteosarcoma is needed to assess its prognostic significance compared with humans. Ultimately, a comparative understanding of T and NK cells in the osteosarcoma tumor microenvironment in both dogs and humans can be a platform for translational studies that improve outcomes in both dogs and humans with this frequently aggressive disease.

Comparative Immunogenomics of Canine Natural Killer Cells as Immunotherapy Target.

Natural killer (NK) cells are key effectors of the innate immune system, but major differences between human and murine NK cells have impeded translation. Outbred dogs offer an important link for studies of NK biology and immunotherapy. We analyzed gene expression of putative NK populations from healthy dogs and dogs with naturally-occurring cancers examining differential gene expression across multiple conditions, including steady-state, in vitro activation with cytokines and co-culture, and in vivo activation with inhaled IL-15 in dogs receiving IL-15 immunotherapy. We also compared dog, mouse and human CD3-NKp46+ NK cells using a novel orthologous transcriptome. Distinct transcriptional profiles between NK populations exist between conditions and in vitro versus in vivo treatments. In cross-species analysis, canine NK cells were globally more similar to human NK cells than mice. These data define canine NK cell gene expression under multiple conditions and across species, filling an important gap in translational NK studies.

Chemotherapy After Diagnosis of Malignant Bowel Obstruction is Associated with Superior Survival for Medicare Patients with Advanced Malignancy.

BACKGROUND: Although malignant bowel obstruction (MBO) often is a terminal event, systemic therapies are advocated for select patients to extend survival. This study aimed to evaluate factors associated with receipt of chemotherapy after MBO and to determine whether chemotherapy after MBO is associated with survival. METHODS: This retrospective cohort study investigated patients 65 years of age or older with metastatic gastrointestinal, gynecologic, or genitourinary cancers who were hospitalized with MBO from 2008 to 2012 using the Surveillance, Epidemiology, and End Results (SEER)-Medicare database. Fine and Gray models were used to identify factors associated with receipt of chemotherapy accounting for the competing risk of death. Cox models identified factors associated with overall survival. RESULTS: Of the 2983 MBO patients, 39% (n = 1169) were treated with chemotherapy after MBO. No differences in receipt of chemotherapy between the surgical and medical patients were found in the univariable analysis (subdistribution hazard ratio [SHR], 0.96; 95% confidence interval [CI], 0.86-1.07; p = 0.47) or multivariable analysis (SHR, 1.12; 95% CI, 1.00-1.26; p = 0.06). Older age, African American race, medical comorbidities, non-colorectal and non-ovarian cancer diagnoses, sepsis, ascites, and intensive care unit stays were inversely associated with receipt of chemotherapy after MBO (p < 0.05). Chemotherapy with surgery was associated with longer survival than surgery (adjusted hazard ratio [aHR], 2.97; 95% CI, 2.65-3.34; p < 0.01) or medical management without chemotherapy (aHR, 4.56; 95% CI, 4.04-5.14; p < 0.01). Subgroup analyses of biologically diverse cancers (colorectal, pancreatic, and ovarian) showed similar results, with greater survival related to chemotherapy (p < 0.05). CONCLUSIONS: Chemotherapy plays an integral role in maximizing oncologic outcome for select patients with MBO. The data from this study are critical to optimizing multimodality care for these complex patients.

Analysis of tumor-infiltrating NK and T cells highlights IL-15 stimulation and TIGIT blockade as a combination immunotherapy strategy for soft tissue sarcomas.

PURPOSE: Given the unmet need for novel immunotherapy in soft tissue sarcoma (STS), we sought to characterize the phenotype and function of intratumoral natural killer (NK) and T cells to identify novel strategies to augment tumor-infiltrating lymphocyte (TIL) function. EXPERIMENTAL DESIGN: Using prospectively collected specimens from dogs and humans with sarcomas, archived specimens, and The Cancer Genome Atlas (TCGA) data, we evaluated blood and tumor NK and T cell phenotype and function and correlated those with outcome. We then assessed the effects of interleukin 15 (IL-15) stimulation on both NK and T cell activation and TIGIT upregulation. Finally, we evaluated cytotoxic effects of IL-15 combined with TIGIT blockade using a novel anti-TIGIT antibody. RESULTS: TILs were strongly associated with survival outcome in both archived tissue and TCGA, but higher TIL content was also associated with higher TIGIT expression. Compared with blood, intratumoral NK and T cells showed significantly higher expression of both activation and exhaustion markers, in particular TIGIT. Ex vivo stimulation of blood and tumor NK and T cells from patients with STS with IL-15 further increased both activation and exhaustion markers, including TIGIT. Dogs with metastatic osteosarcoma receiving inhaled IL-15 also exhibited upregulation of activation markers and TIGIT. Ex vivo, combined IL-15 and TIGIT blockade using STS blood and tumor specimens significantly increased cytotoxicity against STS targets. CONCLUSION: Intratumoral NK and T cells are prognostic in STS, but their activation is marked by significant upregulation of TIGIT. Our data suggest that combined IL-15 and TIGIT blockade may be a promising clinical strategy in STS.

Disparities in the Occurrence of Late Effects following Treatment among Adolescent and Young Adult Melanoma Survivors.

BACKGROUND: Melanoma is the third most common cancer in the adolescent and young adult (AYA) population; however, no studies have addressed the occurrence of adverse health conditions following melanoma treatment in these survivors. METHODS: Data for patients ages 15 to 39 years diagnosed with cutaneous melanoma from 1996 to 2012 and surviving ≥2 years were obtained from the California Cancer Registry and linked to statewide hospitalization data. The influence of age at diagnosis, sex, race/ethnicity, neighborhood socioeconomic status (SES), health insurance, and surgery on the development of adverse health conditions was evaluated using Cox proportional hazards regression models. RESULTS: Of 8,259 patients, 35.3% were male, 83.3% were non-Hispanic White, 82.4% had private health insurance, and 60.5% were considered high SES. In Cox regression models, males had an increased risk of developing adverse health conditions across all systems, including cardiac [HR, 1.73, 95% confidence interval (CI), 1.47-2.03], lymphedema (HR, 1.56; 95% CI, 1.37-1.77), hematologic disorders (HR, 1.17; 95% CI, 1.03-1.33), major infection/sepsis (HR, 1.59; 95% CI, 1.39-1.82), and second cancers (HR, 1.51; 95% CI, 1.31-1.74). Patients with public/no insurance (vs. private) had a greater risk of developing all studied adverse health conditions, including subsequent cancers (HR, 2.34; 95% CI, 1.94-2.82). AYA patients residing in low SES neighborhoods had similar increased risk of developing adverse health conditions. CONCLUSIONS: Of AYA melanoma survivors, males, those with public/no health insurance, and those living in low SES neighborhoods had a greater likelihood of developing adverse health conditions. IMPACT: Strategies to improve surveillance and secondary prevention of these adverse health conditions are needed among AYA melanoma survivors, specifically for the at-risk populations identified.

Radiotherapy is Associated With Improved Survival in Patients With Synovial Sarcoma Undergoing Surgery: A National Cancer Database Analysis.

BACKGROUND: Previous studies have demonstrated an association of perioperative radiotherapy (RT) with improved survival in patients with synovial sarcoma (SS) undergoing surgery, but the mechanism for this is unknown. In this study, we sought to further analyze this association using a hospital-based data set where data on chemotherapy administration and surgical margin status are available. METHODS: Using the National Cancer Database, we identified 1216 patients with SS (aged ≥18 y) from 2004-2012 undergoing surgery. Cox proportional hazards analysis was used to study the effect of clinicopathologic variables on overall survival (OS). RESULTS: Mean age at diagnosis was 41.5 y (range 18-90), and 71.3% of tumors were high grade; 22.9% underwent surgery alone, 59.6% received RT with surgery, 44.2% received chemotherapy with surgery, and 26.3% received trimodality therapy. Age, sex, grade, Charlson-Deyo score, and RT (hazard ratio, 0.676; 95% confidence interval, 0.519-0.880; P = 0.004) were associated with improved OS, whereas chemotherapy (hazard ratio, 1.20; 95% confidence interval, 0.899-1.60; P = 0.217) and surgical margin status were not. Trimodality therapy with surgery, RT, and chemotherapy was associated with improved OS when compared with therapy with surgery and chemotherapy alone. CONCLUSIONS: In patients with SS undergoing surgery, we observed a significant improved association of OS with the addition of RT when adjusting for comorbidity score, margin status, and receipt of chemotherapy. These data further support routine implementation of RT in the treatment of patients with SS, including those receiving aggressive multimodality and trimodality care.

Novel Targets in Melanoma: Intralesional and Combination Therapy to Manipulate the Immune Response.

Clinical outcomes for metastatic melanoma have been dramatically altered by recent developments in immunotherapy and targeted strategies, but response to these therapies is not uniform, the majority of patients do not respond, and clinical response can be self-limited. Current directions in melanoma treatment aim to leverage a combination of therapies for tumors refractory to monoimmunotherapy, to include tumor-directed strategies, such as intralesional therapy and inhibitors designed for novel targets, which may augment current systemic agents when used in combination. Here, we summarize new classes of agents and emerging multimodal combination strategies that demonstrate significant promise in future melanoma management.

Elderly Age Is Associated With More Conservative Treatment of Invasive Melanoma.

BACKGROUND/AIM: Competing mortality risks complicate treatment of elderly melanoma patients potentially leading to conservative management, including no sentinel lymph node biopsy. As systemic immunotherapy offers justification for nodal evaluation, we examined treatment trends among elderly melanoma patients. PATIENTS AND METHODS: We performed a National Cancer Database analysis of melanoma patients from 2004-2015. Patients were categorized by age (elderly ≥80-years-old). Multivariable logistic regression analyses were performed comparing characteristics and treatment by age. RESULTS: Of 187,814 patients, 2.7% were 1-25, 11.6% were 26-40, 46.6% were 41-64, 28.8% were 65-79, and 10.3% were ≥80-years-old with clinicopathologic and treatment differences between age cohorts. Nodal surgery was least common among elderly patients (43.1% vs. 60.7-69.8%, p<0.0001). For stage III, immunotherapy was least common among the elderly (p<0.0001), but associated with greater survival (HR=0.52, 95%CI=0.32-0.84, p=0.008). CONCLUSION: Elderly melanoma patients were often treated conservatively, including no nodal evaluation, concerning for the potential undertreatment of this population.

Blood and tissue biomarker analysis in dogs with osteosarcoma treated with palliative radiation and intra-tumoral autologous natural killer cell transfer.

We have previously reported radiation-induced sensitization of canine osteosarcoma (OSA) to natural killer (NK) therapy, including results from a first-in-dog clinical trial. Here, we report correlative analyses of blood and tissue specimens for signals of immune activation in trial subjects. Among 10 dogs treated with palliative radiotherapy (RT) and intra-tumoral adoptive NK transfer, we performed ELISA on serum cytokines, flow cytometry for immune phenotype of PBMCs, and PCR on tumor tissue for immune-related gene expression. We then queried The Cancer Genome Atlas (TCGA) to evaluate the association of cytotoxic/immune-related gene expression with human sarcoma survival. Updated survival analysis revealed five 6-month survivors, including one dog who lived 17.9 months. Using feeder line co-culture for NK expansion, we observed maximal activation of dog NK cells on day 17-19 post isolation with near 100% expression of granzyme B and NKp46 and high cytotoxic function in the injected NK product. Among dogs on trial, we observed a trend for higher baseline serum IL-6 to predict worse lung metastasis-free and overall survival (P = 0.08). PCR analysis revealed low absolute gene expression of CD3, CD8, and NKG2D in untreated OSA. Among treated dogs, there was marked heterogeneity in the expression of immune-related genes pre- and post-treatment, but increases in CD3 and CD8 gene expression were higher among dogs that lived > 6 months compared to those who did not. Analysis of the TCGA confirmed significant differences in survival among human sarcoma patients with high and low expression of genes associated with greater immune activation and cytotoxicity (CD3e, CD8a, IFN-γ, perforin, and CD122/IL-2 receptor beta). Updated results from a first-in-dog clinical trial of palliative RT and autologous NK cell immunotherapy for OSA illustrate the translational relevance of companion dogs for novel cancer therapies. Similar to human studies, analyses of immune markers from canine serum, PBMCs, and tumor tissue are feasible and provide insight into potential biomarkers of response and resistance.

Characterization and Potential Applications of Dog Natural Killer Cells in Cancer Immunotherapy.

Natural killer (NK) cells of the innate immune system are a key focus of research within the field of immuno-oncology based on their ability to recognize and eliminate malignant cells without prior sensitization or priming. However, barriers have arisen in the effective translation of NK cells to the clinic, in part because of critical species differences between mice and humans. Companion animals, especially dogs, are valuable species for overcoming many of these barriers, as dogs develop spontaneous tumors in the setting of an intact immune system, and the genetic and epigenetic factors that underlie oncogenesis appear to be similar between dogs and humans. Here, we summarize the current state of knowledge for dog NK cells, including cell surface marker phenotype, key NK genes and genetic regulation, similarities and differences of dog NK cells to other mammals, especially human and mouse, expression of canonical inhibitory and activating receptors, ex vivo expansion techniques, and current and future clinical applications. While dog NK cells are not as well described as those in humans and mice, the knowledge of the field is increasing and clinical applications in dogs can potentially advance the field of human NK biology and therapy. Better characterization is needed to truly understand the similarities and differences of dog NK cells with mouse and human. This will allow for the canine model to speed clinical translation of NK immunotherapy studies and overcome key barriers in the optimization of NK cancer immunotherapy, including trafficking, longevity, and maximal in vivo support.

Defining Value for Pancreatic Surgery in Early-Stage Pancreatic Cancer.

Importance: Value-based care is increasingly important, with rising health care costs and advances in cancer treatment leading to greater survival for patients with cancer. Regionalization of surgical care for pancreatic cancer has been extensively studied as a strategy to improve perioperative outcomes, but investigation of long-term outcomes relative to health care costs (ie, value) is lacking. Objective: To identify patient and hospital characteristics associated with improved overall survival, decreased costs, and greater value among patients with pancreatic cancer undergoing curative resection. Design, Setting, and Participants: This retrospective cohort study identified 2786 patients with stages I to II pancreatic cancer who underwent pancreatic resection at 157 hospitals from January 1, 2004, through December 31, 2012. The study used the California Cancer Registry, which collects data from all California residents newly diagnosed with cancer, linked to the Office of Statewide Health Planning and Development database, which collects administrative data from all California licensed hospitals. Data were analyzed from November 11, 2017, through September 4, 2018. Exposures: Pancreatic resection at high-volume and/or National Cancer Institute (NCI)-designated cancer centers. Main Outcomes and Measures: The primary outcomes were overall survival, surgical hospitalization costs, and value. High value was defined as the fourth quintile or higher for survival and the second quintile or less for costs. Costs were calculated from charges using cost-charge ratios and adjusted for geographic variation and inflation. Multivariable regression models were used to determine factors associated with overall survival, costs, and high value. Results: Among the 2786 patients included (1394 [50.0%] male; mean [SD] age, 67.0 [10.7] years), postoperative chemotherapy (adjusted hazard ratio [aHR], 0.71; 95% CI, 0.64-0.79; P < .001) and high-volume centers (aHR, 0.78; 95% CI, 0.61-0.99; P = .04) were associated with greater overall survival. Higher Elixhauser comorbidity index scores (estimate, 0.006; 95% CI, 0.003-0.008), complications (estimate, 0.22; 95% CI, 0.17-0.27), readmissions (estimate, 0.34; 95% CI, 0.29-0.39), and longer lengths of stay (estimate, 0.03; 95% CI, 0.03-0.04) were associated with higher costs (P < .001), whereas postoperative chemotherapy was associated with lower costs (estimate, -0.06; 95% CI, -0.11 to -0.02; P = .006). National Cancer Institute-designated and high-volume centers were not associated with costs. Although grades III and IV tumors (odds ratio [OR], 0.65; 95% CI, 0.39-0.91; P = .001), T3 category disease (OR, 0.71; 95% CI, 0.46-0.95; P = .005), complications (OR, 0.68; 95% CI, 0.49-0.86; P < .001), readmissions (OR, 0.64; 95% CI, 0.44-0.84; P < .001), and length of stay (OR, 0.82; 95% CI, 0.78-0.85; P < .001) were inversely associated with high-value care, NCI designation (OR, 1.07; 95% CI, 0.66-1.49; P = .74) and high-volume centers (OR, 1.08; 95% CI, 0.54-1.61; P = .07) were not. Conclusions and Relevance: In this study, high-value care was associated with important patient characteristics and postoperative outcomes. However, NCI-designated and high-volume centers were not associated with greater value. These data suggest that targeted measures to enhance value may be needed in these centers.

Role of Radiation Therapy in Adult Extraskeletal Ewing's Sarcoma Patients Treated with Chemotherapy and Surgery.

Radiation therapy (RT) is advocated in the multimodal treatment of high-grade soft tissue sarcoma (STS), but its role may be less clear in chemotherapy-sensitive STS such as extraskeletal Ewing sarcoma (EES). The purpose of this study was to determine the role of RT on overall survival (OS) in localized EES adult patients treated with chemotherapy and surgery. Adult patients diagnosed with EES and reported to the National Cancer Database from 2004 to 2014 were evaluated. All patients were treated with surgical resection. Patient demographics, tumor characteristics, treatments received, resection margins, and survival were examined for the 232 patients identified. Using multivariate analysis and Cox proportional hazard analysis, predictors of OS were determined. In the overall cohort, 40 percent of patients received RT and 78 percent received chemotherapy, with 31 percent receiving both. The addition of RT to the patients receiving surgery + chemotherapy did not improve OS (p < 0.05). Twenty-four percent of patients who achieved R0 resection after surgery still received RT without any improvement in OS. Patients treated at community cancer centers were more likely to receive additional RT compared with Comprehensive Cancer Centers (p < 0.05). In adult EES patients with localized disease treated with chemotherapy and surgery, the addition of RT does not improve overall survival.

Extremity soft tissue sarcoma in the elderly: Are we overtreating or undertreating this potentially vulnerable patient population?

BACKGROUND: As the U.S. population ages, differences in oncologic outcomes among the elderly have been recognized. Our objective was to analyze the clinical, pathologic, and treatment outcomes for elderly soft tissue sarcoma (STS) patients, hypothesizing significant differences in the management and response to therapy. METHODS: Using the National Cancer Database, we identified 33 859 patients with nonmetastatic extremity STS. We defined elderly as ≥74 years in age and compared patient and treatment variables between adult and elderly patients. Cox-proportional hazards analysis was used to determine predictors of overall survival (OS). RESULTS: We identified 8504 elderly patients. Significant differences in histologic subtype, grade, and facility type between elderly and nonelderly patients (P < 0.05) exist. Elderly patients were less likely to undergo R0 resection (P = 0.001) and had a higher 90-day mortality (P = 0.001). Surgical elderly patients experienced superior OS compared with nonsurgical patients (P = 0.001). Among elderly patients, younger age, and female sex, lower Charlson-Deyo score, lower grade, smaller tumors, surgical resection, negative surgical margins, and radiation therapy were associated with better OS. CONCLUSIONS: Key differences exist in elderly extremity STS patients, including a narrower benefit/risk ratio with surgical management. These data highlight that elderly patients represent a distinct cohort for whom more careful selection appears indicated.