Graphical modeling of causal factors associated with the postoperative survival of esophageal cancer subjects

PURPOSE

To clarify the causal relationship between factors contributing to the postoperative survival of patients with esophageal cancer.

METHODS

A cohort of 195 patients who underwent surgery for esophageal cancer between 2008 and 2021 was used in the study. All patients had preoperative chest computed tomography (CT) and positron emission tomography-CT (PET-CT) scans prior to receiving any treatment. From these images, high throughput and quantitative radiomic features, tumor features, and various body composition features were automatically extracted. Causal relationships among these image features, patient demographics, and other clinicopathological variables were analyzed and visualized using a novel score-based directed graph called "Grouped Greedy Equivalence Search" (GGES) while taking prior knowledge into consideration. After supplementing and screening the causal variables, the intervention do-calculus adjustment (IDA) scores were calculated to determine the degree of impact of each variable on survival. Based on this IDA score, a GGES prediction formula was generated. Ten-fold cross-validation was used to assess the performance of the models. The prediction results were evaluated using the R-Squared Score (R2 score).

RESULTS

The final causal graphical model was formed by two PET-based image variables, ten body composition variables, four pathological variables, four demographic variables, two tumor variables, and one radiological variable (Percentile 10). Intramuscular fat mass was found to have the most impact on overall survival month. Percentile 10 and overall TNM (T: tumor, N: nodes, M: metastasis) stage were identified as direct causes of overall survival (month). The GGES casual model outperformed GES in regression prediction (R2  = 0.251) (p < 0.05) and was able to avoid unreasonable causality that may contradict common sense.

CONCLUSION

The GGES causal model can provide a reliable and straightforward representation of the intricate causal relationships among the variables that impact the postoperative survival of patients with esophageal cancer.

Orchestrating Resilience: How Neuropilin-2 and Macrophages Contribute to Cardiothoracic Disease

Immunity has evolved to balance the destructive nature of inflammation with wound healing to overcome trauma, infection, environmental insults, and rogue malignant cells. The inflammatory response is marked by overlapping phases of initiation, resolution, and post-resolution remodeling. However, the disruption of these events can lead to prolonged tissue damage and organ dysfunction, resulting long-term disease states. Macrophages are the archetypic phagocytes present within all tissues and are important contributors to these processes. Pleiotropic and highly plastic in their responses, macrophages support tissue homeostasis, repair, and regeneration, all while balancing immunologic self-tolerance with the clearance of noxious stimuli, pathogens, and malignant threats. Neuropilin-2 (Nrp2), a promiscuous co-receptor for growth factors, semaphorins, and integrins, has increasingly been recognized for its unique role in tissue homeostasis and immune regulation. Notably, recent studies have begun to elucidate the role of Nrp2 in both non-hematopoietic cells and macrophages with cardiothoracic disease. Herein, we describe the unique role of Nrp2 in diseases of the heart and lung, with an emphasis on Nrp2 in macrophages, and explore the potential to target Nrp2 as a therapeutic intervention.

Comparison of robotic-assisted minimally invasive esophagectomy versus minimally invasive esophagectomy: A propensity-matched study from a single high-volume institution

OBJECTIVE

Robotic-assisted minimally invasive esophagectomy accounts for a growing proportion of esophagectomies, potentially due to improved technical capabilities simplifying the challenging aspects of standard minimally invasive esophagectomy. However, there is limited evidence directly comparing both operations. The objective is to evaluate the short-term and long-term outcomes of robotic-assisted minimally invasive esophagectomy in comparison with the minimally invasive esophagectomy approach for patients with esophageal cancer over a 7-year period at a high-volume center. The primary end points of this study were overall survival and disease-free survival. Secondary end points included operation-specific morbidity, lymph node yield, readmission status, and in-hospital, 30-day, and 90-day mortality.

METHODS

Patients who underwent robotic-assisted minimally invasive esophagectomy or standard minimally invasive esophagectomy over a 7-year period were identified from a prospectively maintained database. Inclusion criteria were patients with stage I to III disease, operations performed past the learning curve, and no evidence of scleroderma or cirrhosis. A 1:3 propensity match (robotic-assisted minimally invasive esophagectomy:minimally invasive esophagectomy) for multiple clinical covariates was performed to identify the final study cohort. Perioperative outcomes were compared between the 2 operations.

RESULTS

A total of 734 patients undergoing minimally invasive esophagectomy (n = 630) or robotic-assisted minimally invasive esophagectomy (n = 104) for esophageal cancer were identified. After exclusions and matching, a total cohort of 246 patients undergoing robotic-assisted minimally invasive esophagectomy (n = 65) or minimally invasive esophagectomy (n = 181) were identified. There was no difference in overall survival (P = .69) or disease-free survival (P = .70). There were no significant differences in rates of major morbidity: pneumonia (17% vs 17%, P = .34), chylothorax (8% vs 9%, P = .95), recurrent laryngeal nerve injury (0% vs 1.5%, P = 1), anastomotic leak (5% vs 4%, P = .49), intraoperative complications (9% vs 8%, P = .73), or complete resection rates (99% vs 96%, P = .68). There was no difference in in-hospital (P = .89), 30-day (P = .66) or 90-day mortality (P = .73) between both cohorts. The robotic-assisted minimally invasive esophagectomy cohort yielded a higher median lymph node harvest in comparison with the minimally invasive esophagectomy cohort (32 vs 29, P = .02).

CONCLUSIONS

Robotic-assisted minimally invasive esophagectomy may improve lymphadenectomy in patients undergoing esophagectomy for cancer. Minimally invasive esophagectomy and robotic-assisted minimally invasive esophagectomy are otherwise associated with similar mortality, morbidity, and perioperative outcomes. Further prospective study is required to investigate whether improved lymph node resection may translate to improved oncologic outcomes.

A Graph-Based Approach to Identify Factors Contributing to Postoperative Lung Cancer Recurrence among Patients with Non-Small-Cell Lung Cancer

The accurate identification of the preoperative factors impacting postoperative cancer recurrence is crucial for optimizing neoadjuvant and adjuvant therapies and guiding follow-up treatment plans. We modeled the causal relationship between radiographical features derived from CT scans and the clinicopathologic factors associated with postoperative lung cancer recurrence and recurrence-free survival. A retrospective cohort of 363 non-small-cell lung cancer (NSCLC) patients who underwent lung resections with a minimum 5-year follow-up was analyzed. Body composition tissues and tumor features were quantified based on preoperative whole-body CT scans (acquired as a component of PET-CT scans) and chest CT scans, respectively. A novel causal graphical model was used to visualize the causal relationship between these factors. Variables were assessed using the intervention do-calculus adjustment (IDA) score. Direct predictors for recurrence-free survival included smoking history, T-stage, height, and intramuscular fat mass. Subcutaneous fat mass, visceral fat volume, and bone mass exerted the greatest influence on the model. For recurrence, the most significant variables were visceral fat volume, subcutaneous fat volume, and bone mass. Pathologic variables contributed to the recurrence model, with bone mass, TNM stage, and weight being the most important. Body composition, particularly adipose tissue distribution, significantly and causally impacted both recurrence and recurrence-free survival through interconnected relationships with other variables.

CT-derived body composition associated with lung cancer recurrence after surgery

OBJECTIVES

To evaluate the impact of body composition derived from computed tomography (CT) scans on postoperative lung cancer recurrence.

METHODS

We created a retrospective cohort of 363 lung cancer patients who underwent lung resections and had verified recurrence, death, or at least 5-year follow-up without either event. Five key body tissues and ten tumor features were automatically segmented and quantified based on preoperative whole-body CT scans (acquired as part of a PET-CT scan) and chest CT scans, respectively. Time-to-event analysis accounting for the competing event of death was performed to analyze the impact of body composition, tumor features, clinical information, and pathological features on lung cancer recurrence after surgery. The hazard ratio (HR) of normalized factors was used to assess individual significance univariately and in the combined models. The 5-fold cross-validated time-dependent receiver operating characteristics analysis, with an emphasis on the area under the 3-year ROC curve (AUC), was used to characterize the ability to predict lung cancer recurrence.

RESULTS

Body tissues that showed a standalone potential to predict lung cancer recurrence include visceral adipose tissue (VAT) volume (HR = 0.88, p = 0.047), subcutaneous adipose tissue (SAT) density (HR = 1.14, p = 0.034), inter-muscle adipose tissue (IMAT) volume (HR = 0.83, p = 0.002), muscle density (HR = 1.27, p < 0.001), and total fat volume (HR = 0.89, p = 0.050). The CT-derived muscular and tumor features significantly contributed to a model including clinicopathological factors, resulting in an AUC of 0.78 (95% CI: 0.75-0.83) to predict recurrence at 3 years.

CONCLUSIONS

Body composition features (e.g., muscle density, or muscle and inter-muscle adipose tissue volumes) can improve the prediction of recurrence when combined with clinicopathological factors.

CT-Derived Body Composition Is a Predictor of Survival after Esophagectomy

BACKGROUND

Body composition can be accurately quantified based on computed tomography (CT) and typically reflects an individual's overall health status. However, there is a dearth of research examining the relationship between body composition and survival following esophagectomy.

METHODS

We created a cohort consisting of 183 patients who underwent esophagectomy for esophageal cancer without neoadjuvant therapy. The cohort included preoperative PET-CT scans, along with pathologic and clinical data, which were collected prospectively. Radiomic, tumor, PET, and body composition features were automatically extracted from the images. Cox regression models were utilized to identify variables associated with survival. Logistic regression and machine learning models were developed to predict one-, three-, and five-year survival rates. Model performance was evaluated based on the area under the receiver operating characteristics curve (ROC/AUC). To test for the statistical significance of the impact of body composition on survival, body composition features were excluded for the best-performing models, and the DeLong test was used.

RESULTS

The one-year survival model contained 10 variables, including three body composition variables (bone mass, bone density, and visceral adipose tissue (VAT) density), and demonstrated an AUC of 0.817 (95% CI: 0.738-0.897). The three-year survival model incorporated 14 variables, including three body composition variables (intermuscular adipose tissue (IMAT) volume, IMAT mass, and bone mass), with an AUC of 0.693 (95% CI: 0.594-0.792). For the five-year survival model, 10 variables were included, of which two were body composition variables (intramuscular adipose tissue (IMAT) volume and visceral adipose tissue (VAT) mass), with an AUC of 0.861 (95% CI: 0.783-0.938). The one- and five-year survival models exhibited significantly inferior performance when body composition features were not incorporated.

CONCLUSIONS

Body composition features derived from preoperative CT scans should be considered when predicting survival following esophagectomy.

Intraoperative Evaluation of Soft Tissue Sarcoma Surgical Margins with Indocyanine Green Fluorescence Imaging

Soft tissue sarcomas (STS) are rare malignant tumors often associated with poor outcomes and high local recurrence rates. Current tools for intraoperative and definitive margin assessment include intraoperative frozen section and permanent pathology, respectively. Indocyanine green dye (ICG) is a historically safe fluorophore dye that has demonstrated efficacy for intraoperative margin assessment in the surgical management of both breast and gastrointestinal cancers. The utility of ICG in the surgical management of sarcoma surgery has primarily been studied in pre-clinical mouse models and warrants further investigation as a potential adjunct to achieving negative margins. This study is a prospective, non-randomized clinical study conducted on patients with confirmed or suspected STS. Patients younger than 18 years, with a prior adverse reaction to iodine or fluorescein, or with renal disease were excluded from the study. Intravenous ICG was infused approximately three hours prior to surgery at a dosage of 2.0-2.5 mg/kg, and following tumor resection, the excised tumor and tumor bed were imaged for fluorescence intensity. When scanning the tumor bed, a threshold of 77% calibrated to the region of maximum intensity in the resected tumor was defined as a positive ICG margin, according to published protocols from the breast cancer literature. ICG results were then compared with the surgeon's clinical impression of margin status and permanent pathology results. Out of 26 subjects recruited for the original study, 18 soft tissue sarcomas (STS) were included for analysis. Three subjects were excluded for having bone sarcomas, and five subjects were excluded due to final pathology, which was ultimately inconsistent with sarcoma. The average age of patients was 64.1 years old (range: 28-83), with an average ICG dose of 201.8 mg. In 56% (10/18) of patients, ICG margins were consistent with the permanent pathology margins, with 89% specificity. The use of ICG as an intraoperative adjunct to obtaining negative margins in soft tissue sarcoma surgery is promising. However, studies with larger sample sizes are warranted to further delineate the accuracy, optimal dosage, timing, and types of sarcoma in which this diagnostic tool may be most useful.

Combined exploratory laparotomy, transpsoas, and thoracic approach to resection of a giant spinal ganglioneuroma: illustrative case

BACKGROUND

Ganglioneuromas are rare peripheral nervous system tumors of neural crest origin. Most are often asymptomatic and incidentally found, but large tumors can cause mass effect. Herein, the authors report a case of a giant ganglioneuroma that arose from the lumbar foramina into the retroperitoneal and thoracic cavities.

OBSERVATIONS

A 62-year-old female presented with low back pain, left lower extremity swelling, and increased sensation of an abdominal mass. Surgical treatment options were reviewed with the patient and coordinated care was planned by surgical oncological specialists. The patient opted for multistage exploratory laparotomy for abdominal mobilization, diaphragm resection, and en bloc resection with neuromonitoring. After surgery, the patient experienced significant improvement in symptoms.

LESSONS

A combined surgical exposure involving gastrointestinal, thoracic, and neurological surgeons can be important in the safe resection of ganglioneuromas that span multiple body cavities. Hence, a thorough preoperative assessment could help plan surgery accordingly.

Automated segmentation of five different body tissues on computed tomography using deep learning

PURPOSE

To develop and validate a computer tool for automatic and simultaneous segmentation of five body tissues depicted on computed tomography (CT) scans: visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), intermuscular adipose tissue (IMAT), skeletal muscle (SM), and bone.

METHODS

A cohort of 100 CT scans acquired on different subjects were collected from The Cancer Imaging Archive-50 whole-body positron emission tomography-CTs, 25 chest, and 25 abdominal. Five different body tissues (i.e., VAT, SAT, IMAT, SM, and bone) were manually annotated. A training-while-annotating strategy was used to improve the annotation efficiency. The 10-fold cross-validation method was used to develop and validate the performance of several convolutional neural networks (CNNs), including UNet, Recurrent Residual UNet (R2Unet), and UNet++. A grid-based three-dimensional patch sampling operation was used to train the CNN models. The CNN models were also trained and tested separately for each body tissue to see if they could achieve a better performance than segmenting them jointly. The paired sample t-test was used to statistically assess the performance differences among the involved CNN models RESULTS: When segmenting the five body tissues simultaneously, the Dice coefficients ranged from 0.826 to 0.840 for VAT, from 0.901 to 0.908 for SAT, from 0.574 to 0.611 for IMAT, from 0.874 to 0.889 for SM, and from 0.870 to 0.884 for bone, which were significantly higher than the Dice coefficients when segmenting the body tissues separately (p < 0.05), namely, from 0.744 to 0.819 for VAT, from 0.856 to 0.896 for SAT, from 0.433 to 0.590 for IMAT, from 0.838 to 0.871 for SM, and from 0.803 to 0.870 for bone.

CONCLUSION

There were no significant differences among the CNN models in segmenting body tissues, but jointly segmenting body tissues achieved a better performance than segmenting them separately.

Preoperative Rehabilitation Is Feasible in the Weeks Prior to Surgery and Significantly Improves Functional Performance

BACKGROUND

Frailty is a multidimensional state of increased vulnerability. Frail patients are at increased risk for poor surgical outcomes. Prior research demonstrates that rehabilitation strategies deployed after surgery improve outcomes by building strength.

OBJECTIVES

Examine the feasibility and impact of a novel, multi-faceted prehabilitation intervention for frail patients before surgery.

DESIGN

Single arm clinical trial.

SETTING

Veterans Affairs hospital.

PARTICIPANTS

Patients preparing for major abdominal, urological, thoracic, or cardiac surgery with frailty identified as a Risk Analysis Index≥30.

INTERVENTION

Prehabilitation started in a supervised setting to establish safety and then transitioned to home-based exercise with weekly telephone coaching by exercise physiologists. Prehabilitation included (a)strength and coordination training; (b)respiratory muscle training (IMT); (c)aerobic conditioning; and (d)nutritional coaching and supplementation. Prehabilitation length was tailored to the 4-6 week time lag typically preceding each participant's normally scheduled surgery.

MEASUREMENTS

Functional performance and patient surveys were assessed at baseline, every other week during prehabilitation, and then 30 and 90 days after surgery. Within-person changes were estimated using linear mixed models.

RESULTS

43 patients completed baseline assessments; 36(84%) completed a median 5(range 3-10) weeks of prehabilitation before surgery; 32(74%) were retained through 90-day follow-up. Baseline function was relatively low. Exercise logs show participants completed 94% of supervised exercise, 78% of prescribed IMT and 74% of home-based exercise. Between baseline and day of surgery, timed-up-and-go decreased 2.3 seconds, gait speed increased 0.1 meters/second, six-minute walk test increased 41.7 meters, and the time to complete 5 chair rises decreased 1.6 seconds(all P≤0.007). Maximum and mean inspiratory and expiratory pressures increased 4.5, 7.3, 14.1 and 13.5 centimeters of water, respectively(all P≤0.041).

CONCLUSIONS

Prehabilitation is feasible before major surgery and achieves clinically meaningful improvements in functional performance that may impact postoperative outcomes and recovery. These data support rationale for a larger trial powered to detect differences in postoperative outcomes.

Assessing retinal vein occlusion based on color fundus photographs using neural understanding network (NUN)

OBJECTIVE

To develop and validate a novel deep learning architecture to classify retinal vein occlusion (RVO) on color fundus photographs (CFPs) and reveal the image features contributing to the classification.

METHODS

The neural understanding network (NUN) is formed by two components: (1) convolutional neural network (CNN)-based feature extraction and (2) graph neural networks (GNN)-based feature understanding. The CNN-based image features were transformed into a graph representation to encode and visualize long-range feature interactions to identify the image regions that significantly contributed to the classification decision. A total of 7062 CFPs were classified into three categories: (1) no vein occlusion ("normal"), (2) central RVO, and (3) branch RVO. The area under the receiver operative characteristic (ROC) curve (AUC) was used as the metric to assess the performance of the trained classification models.

RESULTS

The AUC, accuracy, sensitivity, and specificity for NUN to classify CFPs as normal, central occlusion, or branch occlusion were 0.975 (± 0.003), 0.911 (± 0.007), 0.983 (± 0.010), and 0.803 (± 0.005), respectively, which outperformed available classical CNN models.

CONCLUSION

The NUN architecture can provide a better classification performance and a straightforward visualization of the results compared to CNNs.

Estimating 3-D whole-body composition from a chest CT scan

BACKGROUND

Estimating whole-body composition from limited region-computed tomography (CT) scans has many potential applications in clinical medicine; however, it is challenging.

PURPOSE

To investigate if whole-body composition based on several tissue types (visceral adipose tissue [VAT], subcutaneous adipose tissue [SAT], intermuscular adipose tissue [IMAT], skeletal muscle [SM], and bone) can be reliably estimated from a chest CT scan only.

METHODS

A cohort of 97 lung cancer subjects who underwent both chest CT scans and whole-body positron emission tomography-CT scans at our institution were collected. We used our in-house software to automatically segment and quantify VAT, SAT, IMAT, SM, and bone on the CT images. The field-of-views of the chest CT scans and the whole-body CT scans were standardized, namely, from vertebra T1 to L1 and from C1 to the bottom of the pelvis, respectively. Multivariate linear regression was used to develop the computer models for estimating the volumes of whole-body tissues from chest CT scans. Subject demographics (e.g., gender and age) and lung volume were included in the modeling analysis. Ten-fold cross-validation was used to validate the performance of the prediction models. Mean absolute difference (MAD) and R-squared (R² ) were used as the performance metrics to assess the model performance.

RESULTS

The R² values when estimating volumes of whole-body SAT, VAT, IMAT, total fat, SM, and bone from the regular chest CT scans were 0.901, 0.929, 0.900, 0.933, 0.928, and 0.918, respectively. The corresponding MADs (percentage difference) were 1.44 ± 1.21 L (12.21% ± 11.70%), 0.63 ± 0.49 L (29.68% ± 61.99%), 0.12 ± 0.09 L (16.20% ± 18.42%), 1.65 ± 1.40 L (10.43% ± 10.79%), 0.71 ± 0.68 L (5.14% ± 4.75%), and 0.17 ± 0.15 L (4.32% ± 3.38%), respectively.

CONCLUSION

Our algorithm shows promise in its ability to estimate whole-body compositions from chest CT scans. Body composition measures based on chest CT scans are more accurate than those based on vertebra third lumbar.

State of the Art in Lung Nodule Localization

Lung nodule and ground-glass opacity localization for diagnostic and therapeutic purposes is often a challenge for thoracic surgeons. While there are several adjuncts and techniques in the surgeon's armamentarium that can be helpful, accurate localization persists as a problem without a perfect solution. The last several decades have seen tremendous improvement in our ability to perform major operations with minimally invasive procedures and resulting lower morbidity. However, technological advances have not been as widely realized for lung nodule localization to complement minimally invasive surgery. This review describes the latest advances in lung nodule localization technology while also demonstrating that more efforts in this area are needed.

A Program to Reduce Post-Operative Opioid Prescribing at a Veteran's Affairs Hospital

Variability in surgeon prescribing patterns is common in the post-operative period and can be the nidus for dependence and addiction. This project aims to reduce opioid overprescribing at the Veteran’s Affairs Pittsburgh Healthcare System (VAPHS). The VAPHS Opioid Stewardship Committee collaborated to create prescribing guidelines for inpatient and outpatient general, thoracic, and vascular surgery procedures. We incorporated bundled order sets into the provider workflow in the electronic medical system and performed a retrospective cohort study comparing opioid prescription patterns for Veterans who underwent any surgical procedure for a three-month period pre- and post- guideline implementation. After implementation of opioid prescribing guidelines, morphine milligram equivalents (MME), quantity of pills prescribed, and days prescribed were statistically significantly reduced for procedures with associated guidelines, including cholecystectomy (MME 140.8 vs. 57.5, p = 0.002; quantity 18.8 vs. 8, p = 0.002; days 5.1 vs. 2.8, p = 0.021), inguinal hernia repair (MME 129.9 vs. 45.3, p = 0.002; quantity 17.3 vs. 6.1, p = 0.002; days 5.0 vs. 2.4, p = 0.002), and umbilical hernia repair (MME 128.8 vs. 53.8, p = 0.002; quantity 17.1 vs. 7.8, p = 0.002; days 5.1 vs. 2.5, p = 0.022). Procedures without associated recommendations also preceded a decrease in overall opioid prescribing. Post-operative opioid prescribing guidelines can steer clinicians toward more conscientious opioid disbursement. There may also be reductions in prescribing opioids for procedures without guidelines as an indirect effect of practice change.

Isoforms of Neuropilin-2 Denote Unique Tumor-Associated Macrophages in Breast Cancer

Tumor-associated macrophages (TAMs) exert profound influence over breast cancer progression, promoting immunosuppression, angiogenesis, and metastasis. Neuropilin-2 (NRP2), consisting of the NRP2a and NRP2b isoforms, is a co-receptor for heparin-binding growth factors including VEGF-C and Class 3 Semaphorins. Selective upregulation in response to environmental stimuli and independent signaling pathways endow the NRP2 isoforms with unique functionality, with NRP2b promoting increased Akt signaling via receptor tyrosine kinases including VEGFRs, MET, and PDGFR. Although NRP2 has been shown to regulate macrophage/TAM biology, the role of the individual NRP2a/NRP2b isoforms in TAMs has yet to be evaluated. Using transcriptional profiling and spectral flow cytometry, we show that NRP2 isoform expression was significantly higher in TAMs from murine mammary tumors. NRP2a/NRP2b levels in human breast cancer metastasis were dependent upon the anatomic location of the tumor and significantly correlated with TAM infiltration in both primary and metastatic breast cancers. We define distinct phenotypes of NRP2 isoform-expressing TAMs in mouse models of breast cancer and within malignant pleural effusions from breast cancer patients which were exclusive of neuropilin-1 expression. Genetic depletion of either NRP2 isoform in macrophages resulted in a dramatic reduction of LPS-induced IL-10 production, defects in phagosomal processing of apoptotic breast cancer cells, and increase in cancer cell migration following co-culture. By contrast, depletion of NRP2b, but not NRP2a, inhibited production of IL-6. These results suggest that NRP2 isoforms regulate both shared and unique functionality in macrophages and are associated with distinct TAM subsets in breast cancer.

Intrapleural interleukin-2-expressing oncolytic virotherapy enhances acute antitumor effects and T-cell receptor diversity in malignant pleural disease

OBJECTIVE

The mainstay of treatment for patients with malignant pleural disease is fluid drainage and systemic therapy. A tumor-specific oncolytic virus or T-cell-activating interleukin-2 immunotherapy may provide an opportunity for local control. We previously developed a vaccinia virus-expressing interleukin-2, an oncolytic virus that mediated tumor regression in preclinical peritoneal tumor models with expansion of tumor-infiltrating lymphocytes. We evaluated the antitumor efficacy and immune modulatory effects of vaccinia virus-expressing interleukin-2 in malignant pleural disease.

METHODS

A murine model of malignant pleural disease was established with percutaneous intrapleural deposition of the Lewis lung carcinoma cell line and monitored with bioluminescent imaging. After intrapleural or systemic administration of vaccinia viruses (vaccinia virus yellow fluorescent protein control, vaccinia virus-expressing interleukin-2), systemic anti-programmed cell death-1 antibody, or combination therapy (vaccinia virus-expressing interleukin-2 and anti-programmed cell death-1), tumor mass, immune cell infiltration, T-cell receptor diversity, and survival were assessed.

RESULTS

Intrapleural vaccinia virus resulted in significant tumor regression compared with phosphate-buffered saline control (P < .05). Inclusion of the interleukin-2 transgene further increased intratumoral CD8+ T cells (P < .01) and programmed cell death-1 expression on CD8+ tumor-infiltrating lymphocytes (P < .001). Intrapleural vaccinia virus-expressing interleukin-2 was superior to systemic vaccinia virus-expressing interleukin-2, with reduced tumor burden (P < .0001) and improved survival (P < .05). Intrapleural vaccinia virus-expressing interleukin-2 alone or combined treatment with systemic anti-programmed cell death-1 reduced tumor burden (P < .01), improved survival (P < .01), and increased intratumoral αβ T-cell receptor diversity (P < .05) compared with systemic anti-programmed cell death-1 monotherapy.

CONCLUSIONS

Intrapleural vaccinia virus-expressing interleukin-2 reduced tumor burden and enhanced survival in a murine malignant pleural disease model. Increased CD8+ tumor-infiltrating lymphocytes and αβ T-cell receptor diversity are associated with enhanced response. Clinical trials will enable assessment of intrapleural vaccinia virus-expressing interleukin-2 therapy in patients with malignant pleural disease.

112 Tumor-specific reactivity and effector function of chimeric antigen receptor engineered macrophages targeting MUC1

Background

Chimeric antigen receptors (CAR) have demonstrated remarkable efficacy in licensing T cells for antitumor responses against hematopoietic malignancies but have had limited success against solid tumors. Macrophages, both archetypic phagocytes and professional antigen presenting cells, may exert profound effector functions which complement adaptive cellular immunity.1 Recently, it was shown that human macrophages engineered to express CARs (CAR-Ms) demonstrated antigen-specific phagocytosis, inhibited solid xenograph tumors, and induced an inflammatory tumor microenvironment boosting antitumor T cell responses.2 Kimura et al. previously completed the first prophylactic cancer vaccine trial based on a non-viral antigen, tumor-associated hypoglycosylated Mucin 1 (MUC1).3 A panel of fully-human affinity-matured MUC1-specific antibodies raised in healthy subjects following immunization was identified from these patients.4 Using these MUC1-specific scFv domains for CAR generation, we have now engineered MUC1-targeting CAR-Ms that may potentially possess reduced off-target specificities.

Methods

Lentiviral CAR expression vectors containing the scFv domains of three unique hypoglycosylated MUC1-specific antibodies or a CD20-specific antibody, the CD3zeta signaling domain, and CD28 and OX40 co-stimulatory domains were constructed. The human monocyte/macrophage U937, SC, and THP-1 lines were stably transduced and flow-sort purified to generate MUC1- or CD20-specific CAR-Ms. CAR-Ms were differentiated into macrophages via 48 hour PMA treatment, and subsequently evaluated for antigen-specific function against MUC1- and/or CD20-expressing K562, ZR-75-1, and Raji cells or cancer cells isolated from solid lung tumors or malignant pleural effusions. CAR-M phenotype was evaluated by flow cytometry following in vitro differentiation and polarization with conventional ‘M1’ and ‘M2’ stimuli. Phagocytosis and lysosomal processing of phagocytosed cargo were evaluated by fluorescence microscopy of GFP/CellTrace labeled targets or detection of pH-sensitive pHrodo expression following CAR-M and tumor cell co-culture, respectively. Antigen-specific cytokine production was determined via cytometric bead array following co-culture of CAR-Ms with MUC1- or CD20-expressing tumor cells or 100mer MUC1 peptide.

Results

Differentiated CAR-Ms possessed an inflammatory phenotype expressing IL-8 and CD86 which was further enhanced by IFNgamma or LPS treatment and was resistant to ‘M2’ polarization with conventional stimuli. CAR-Ms exhibited phagocytosis and subsequent lysosomal processing in an antigen-specific manner, with minimal reactivity against tumor cell targets in the absence of the corresponding MUC1 or CD20 antigen. MUC1-specific CAR-Ms stimulated with MUC1 peptide or MUC1+ tumor cells secreted robust levels of pro-inflammatory IL-8, TNFa, and IL-1beta, but not immunosuppressive IL-10.

Conclusions

MUC1-targeting CAR-Ms exert potent tumor-restricted effector function in vitro and may provide a novel treatment strategy either alone or in potential synergistic combination with T cell-mediated immunotherapies.

Acknowledgements

The authors would like to thank Dr. Olivera J. Finn for generously providing reagents and guidance and Dr. Michael T. Lotze for his mentorship. This study was supported by funding from the University of Pittsburgh’s Department of Cardiothoracic Surgery to ACS and RD.

References

Williams CB, Yeh ES, Soloff AC. Tumor-associated macrophages: unwitting accomplices in breast cancer malignancy. Npj Breast Cancer [Internet]. Breast Cancer Research Foundation/Macmillan Publishers Limited; 2016;2:15025. Available from: http://dx.doi.org/10.1038/npjbcancer.2015.25

Klichinsky M, Ruella M, Shestova O, Lu XM, Best A, Zeeman M, et al. Human chimeric antigen receptor macrophages for cancer immunotherapy. Nat Biotechnol 2020;38:947–53.

Kimura T, McKolanis JR, Dzubinski LA, Islam K, Potter DM, Salazar AM, et al. MUC1 Vaccine for Individuals with Advanced Adenoma of the Colon: A Cancer Immunoprevention Feasibility Study. Cancer Prev Res [Internet] 2013;6:18–26. Available from: http://cancerpreventionresearch.aacrjournals.org/content/6/1/18.abstract

Lohmueller JJ, Sato S, Popova L, Chu IM, Tucker MA, Barberena R, et al. Antibodies elicited by the first non-viral prophylactic cancer vaccine show tumor-specificity and immunotherapeutic potential. Sci Rep 2016;6:31740.

Ethics Approval

The study was approved by the University of Pittsburgh’s Institutional Review Board approval number CR19120172-005.

680 Isoforms of neuropilin-2 regulate distinct macrophage functions and are associated with unique tumor-associated macrophages in murine and human breast cancer

Background

Tumor-associated macrophages (TAMs) exert profound influence over breast cancer progression, promoting immunosuppression, angiogenesis, and metastasis.1 Neuropilin-2 (NRP2), consisting of NRP2a and NRP2b isoforms, is a co-receptor for heparin-binding growth factors including VEGF-C and Class 3 Semaphorins. Selective upregulation in response to environmental stimuli and independent signaling pathways endow the NRP2 isoforms with unique functionality.2 3 We have shown that the two isoforms of NRP2 endow opposing functionality to tumor cells due to distinct signaling pathways, with NRP2b promoting metastatic behavior.3 Although NRPs have been shown to regulate macrophage/TAM biology, the role of NRP2 isoforms in TAM functionality has yet to be evaluated.

Methods

To assess the contribution of NRP2 isoforms to macrophage biology, conditional NRP2a and NRP2b knockout mice and stable shRNA knockdown of NRP2a or NRP2b in Raw264.7 macrophages were generated. Phagocytosis, lysosomal processing of phagocytosed cargo, cytokine production, and influence on tumor cell migration were assessed in vitro using NRP2 isoform knockdown macrophages. NRP2 isoform expression was evaluated on TAMs from murine 4T1 and EO771 mammary carcinoma models using spectral cytometry and single-cell qPCR. NRP2 isoforms and approximated immune composition were evaluated in paired primary tumors and distant metastasis using RNAseq in a cohort of 99 breast cancer patients. High-dimensional myeloid phenotyping was performed on malignant pleural effusions (MPEs) from breast cancer patients or effusions of benign origin using 33-color spectral cytometry and unbiased computational analysis.

Results

NRP2 isoform expression was significantly increased in TAMs from murine tumors compared to macrophages from healthy mammary glands. NRP2 isoforms in human primary and metastatic breast cancer were strongly correlated with one another and positively correlated with increased TAMs. Distinct phenotypes of NRP2 isoform-expressing TAMs in were present in 4T1 and EO771 mouse breast cancers and within MPEs from breast cancer patients which were associated with high levels of activation and potential response to a hypoxic tumor niche. Genetic depletion of either NRP2 isoform resulted in dramatic reduction of LPS-induced IL-10 production, defects in phagosomal processing of apoptotic breast cancer cells, and increase in cancer cell migration following co-culture. By contrast, inhibition of IL-6 production was specific in NRP2b knockdown cells while phagocytic uptake of labeled particulates was inhibited only by NPR2a knockdown.

Conclusions

These results demonstrate that NRP2 isoforms regulate both shared and distinct functionality in macrophages and that NRP2 isoform expression identifies unique TAM subsets in breast cancer.

Acknowledgements

This work was supported by awards from the Susan G. Komen Foundation (CCR15329745), U.S. Department of Defense (W81XWH1910650), and American Lung Association/Thoracic Surgery Foundation to ACS. RD was supported by funding from a Department of Veteran's Affairs Career Development Award (CX001771-01A2) and the University of Pittsburgh's Dean Faculty Advancement Award. ESY was supported by the NCI of the NIH under R03 CA245774. MTL was supported by the NCI of the NIH under awards R01CA181450 and R01CA206012 as well as ITTC/UPMCE. RD and ACS were further supported by funding from the Department of Cardiothoracic Surgery.

References

Williams CB, Yeh ES, Soloff AC. Tumor-associated macrophages: unwitting accomplices in breast cancer malignancy. Npj Breast Cancer [Internet]. Breast Cancer Research Foundation/Macmillan Publishers Limited; 2016;2:15025. Available from: http://dx.doi.org/10.1038/npjbcancer.2015.252.

Nasarre P, Gemmill RM, Potiron VA, Roche J, Lu X, Barón AE, et al. Neuropilin-2 is upregulated in lung cancer cells during TGF-β1–Induced epithelial–mesenchymal transition. Cancer Res [Internet] 2013;73:7111 LP–7121. Available from: http://cancerres.aacrjournals.org/content/73/23/7111.abstract3.

Gemmill RM, Nasarre P, Nair-Menon J, Cappuzzo F, Landi L, D'Incecco A, et al. The neuropilin 2 isoform NRP2b uniquely supports TGFβ-mediated progression in lung cancer. Sci Signal [Internet] 2017;10. Available from: http://stke.sciencemag.org/content/10/462/eaag0528.abstract

Ethics Approval

The study was approved by the University of Pittsburgh's Institutional Review Board approval number CR19120172-005.

Prognostic Difference of Pleural versus Distant Metastasis after Surgery for Lung Cancer

Background: Pleural metastasis in lung cancer found at diagnosis has a poor prognosis, with 5–11 months’ survival. We hypothesized that prognosis might be different for patients who have had curative-intent surgery and subsequent pleural recurrence and that survival might differ based on the location of the first metastasis (distant versus pleural). This may clarify if pleural recurrence is a local event or due to systemic disease. Methods: A database of 5089 patients who underwent curative-intent surgery for lung cancer was queried, and 85 patients were found who had biopsy-proven pleural metastasis during surveillance. We examined survival based on pattern of metastasis (pleural first versus distant first/simultaneously). Results: Median survival was 34 months (range: 1–171) from the time of surgery and 13 months (range: 0–153) from the time of recurrence. The shortest median survival after recurrence was in patients with adenocarcinoma and pleural metastasis as the first site (6 months). For patients with pleural metastasis as the first site, those with adenocarcinoma had a significantly shorter post-recurrence survival when compared with squamous cell carcinoma (6 vs. 12 months; HR = 0.34) and a significantly shorter survival from the time of surgery when compared with distant metastases first/simultaneously (25 vs. 52 months; HR = 0.49). Conclusions: Patients who undergo curative-intent surgery for lung adenocarcinoma that have pleural recurrence as the first site have poor survival. This may indicate that pleural recurrence after lung surgery is not likely due to a localized event but rather indicates systemic disease; however, this would require further study.

Experimental respiratory exposure to putative Gulf War toxins promotes persistent alveolar macrophage recruitment and pulmonary inflammation

AIMS

Respiratory disorders are a prominent component of Gulf War Illness. Although much of the underlying mechanisms of Gulf War Illness remain undefined, chronic immune dysfunction is a consistent feature of this multi-symptomatic, multi-organ disorder. Alveolar macrophages represent the predominant mononuclear phagocytes of the pulmonary mucosa, orchestrating the host response to pathogens and environmental stimuli. Herein, we sought to characterize the innate immune response of the pulmonary mucosa, with a focus on macrophages, to experimental respiratory exposure to two putative Gulf War Toxins (GWTs).

MATERIALS AND METHODS

Utilizing commercially available instrumentation, we evaluated the effect of aerosolized exposure to the pesticide malathion and diesel exhaust particulate (DEP) on the immune composition and inflammatory response of the lung in FVB/N mice using multiparametric spectral cytometry, cytokine analysis, and histology.

KEY FINDINGS

Aerosolized GWTs induced gross pulmonary pathology with transient recruitment of neutrophils and sustained accumulation of alveolar macrophages to the lung for up to two weeks after exposure cessation. High-dimensional cytometry and unbiased computational analysis identified novel myeloid subsets recruited to the lung post-exposure driven by an influx of peripheral monocyte-derived progenitors. DEP and malathion, either alone or in combination, induced soluble mediators in bronchoalveolar lavage indicative of oxidative stress (PGF2α), inflammation (LTB4, TNFα, IL-12), and immunosuppression (IL-10), that were sustained or increased two weeks after exposures concluded.

SIGNIFICANCE

These findings indicate that macrophage accumulation and pulmonary inflammation induced by GWTs continue in the absence of toxin exposure and may contribute to the immunopathology of respiratory Gulf War Illness.

Fighting Fire With Fire: Oncolytic Virotherapy for Thoracic Malignancies

Thoracic malignancies are associated with high mortality rates. Conventional therapy for many of the patients with thoracic malignancies is obviated by a high incidence of locoregional recurrence and distant metastasis. Fortunately, developments in immunotherapy provide effective strategies for both local and systemic treatments that have rapidly advanced during the last decade. One promising approach to cancer immunotherapy is to use oncolytic viruses, which have the advantages of relatively high tumor specificity, selective replication-mediated oncolysis, enhanced antigen presentation, and potential for delivery of immunogenic payloads such as cytokines, with subsequent elicitation of effective antitumor immunity. Several oncolytic viruses including adenovirus, coxsackievirus B3, herpes virus, measles virus, reovirus, and vaccinia virus have been developed and applied to thoracic cancers in preclinical murine studies and clinical trials. This review discusses the current state of oncolytic virotherapy in lung cancer, esophageal cancer, and metastatic malignant pleural effusions and considers its potential as an emergent therapeutic for these patients.

Respiratory exposure to putative Gulf War toxins induces phenotypic and transcriptional alterations with effector dysfunction in alveolar macrophages

Respiratory disorders including chronic obstructive pulmonary disease, asthma, and increased susceptibility to lung infections are a prominent component of Gulf War Illness (GWI). Although the mechanisms of GWI are unknown, chronic immune dysfunction is a consistent factor of this multi-symptomatic disorder. Alveolar macrophages (AMs) represent the predominant mononuclear phagocytes of the pulmonary mucosa, orchestrating the host response to pathogens and environmental stimuli via balanced induction of inflammatory, anti-inflammatory, and pro-resolution mediators. Utilizing commercially available instrumentation, we evaluated the effect of aerosolized exposure to two putative GW toxins, the pesticide malathion and diesel exhaust particulate (DEP), on the immune composition and inflammatory response of the lung in FVB/N mice. Toxin exposure resulted in gross lung pathology with variable increases in protein, lactose dehydrogenase, and cytokines in bronchoalveolar lavage (BAL). Aerosolized toxin exposure reduced AMs in the lung and BAL, associated with a shift to wound-healing phenotypes and concomitant influx of monocyte-derived progenitors from the circulation. Exposure to DEP and malathion, either alone or in combination, induced varying levels of dysfunction in flow-sorted AMs ex vivo as determined by inhibited migration, cytokine production, and phagocytosis. Toxin-induced alterations were associated with unique transcriptional profiles following RNA sequencing analysis. Collectively, these findings suggest that respiratory toxin-induced macrophage dysfunction may establish a state of frustrated immune resolution underlying the chronic immunopathology of respiratory GWI.

Predicting benign, preinvasive, and invasive lung nodules on computed tomography scans using machine learning

OBJECTIVE

The study objective was to investigate if machine learning algorithms can predict whether a lung nodule is benign, adenocarcinoma, or its preinvasive subtype from computed tomography images alone.

METHODS

A dataset of chest computed tomography scans containing lung nodules was collected with their pathologic diagnosis from several sources. The dataset was split randomly into training (70%), internal validation (15%), and independent test sets (15%) at the patient level. Two machine learning algorithms were developed, trained, and validated. The first algorithm used the support vector machine model, and the second used deep learning technology: a convolutional neural network. Receiver operating characteristic analysis was used to evaluate the performance of the classification on the test dataset.

RESULTS

The support vector machine/convolutional neural network-based models classified nodules into 6 categories resulting in an area under the curve of 0.59/0.65 when differentiating atypical adenomatous hyperplasia versus adenocarcinoma in situ, 0.87/0.86 with minimally invasive adenocarcinoma versus invasive adenocarcinoma, 0.76/0.72 atypical adenomatous hyperplasia + adenocarcinoma in situ versus minimally invasive adenocarcinoma, 0.89/0.87 atypical adenomatous hyperplasia + adenocarcinoma in situ versus minimally invasive adenocarcinoma + invasive adenocarcinoma, and 0.93/0.92 atypical adenomatous hyperplasia + adenocarcinoma in situ + minimally invasive adenocarcinoma versus invasive adenocarcinoma. Classifying benign versus atypical adenomatous hyperplasia + adenocarcinoma in situ + minimally invasive adenocarcinoma versus invasive adenocarcinoma resulted in a micro-average area under the curve of 0.93/0.94 for the support vector machine/convolutional neural network models, respectively. The convolutional neural network-based methods had higher sensitivities than the support vector machine-based methods but lower specificities and accuracies.

CONCLUSIONS

The machine learning algorithms demonstrated reasonable performance in differentiating benign versus preinvasive versus invasive adenocarcinoma from computed tomography images alone. However, the prediction accuracy varies across its subtypes. This holds the potential for improved diagnostic capabilities with less-invasive means.

Adjuvant chemotherapy for pulmonary sarcomatoid carcinoma: A retrospective analysis of the National Cancer Database

OBJECTIVES

Pulmonary sarcomatoid carcinoma (PSC) is a rarely occurring variant of non-small cell lung cancer with sarcoma-like features. Compared with traditional non-small cell lung cancer, PSC patients typically present later and have poorer prognoses, irrespective of stage. The standard of care is resection, but guidelines for the use of adjuvant chemotherapy have not been established. To advance the development of evidence-based management algorithms for PSC after resection, a statistical analysis on a nationwide representative sample of patients was performed.

METHODS

A retrospective cohort study was performed by querying the National Cancer Database for patients with a diagnosis of PSC between 2004 and 2015. Patients who received complete anatomical resection with or without adjuvant chemotherapy were included. Multivariable regression was used to detect factors associated with the receipt of adjuvant chemotherapy. Multivariable Cox regression of overall survival and Kaplan-Meier survival analysis on propensity-matched groups was conducted to study the association between adjuvant chemotherapy and prognosis.

RESULTS

We included 1497 patients with PSC in the final analysis. Factors associated with receiving adjuvant chemotherapy were age, histology, and receipt of adjuvant radiation. The results of multivariable Cox analysis and Kaplan-Meier analysis on propensity matched groups yielded similar trends: adjuvant chemotherapy was associated with improved 5-year overall survival for stage II and III disease, but not for stage I disease.

CONCLUSIONS

Multiple factors are associated with receipt of adjuvant chemotherapy for PSC, and this treatment appears to be associated with improved survival in stage II and stage III, but not stage I patients.

Racial Disparity in Surgical Therapy for Thymic Malignancies

BACKGROUND

The primary curative treatment for thymic malignancies is surgery. For lung and esophageal cancer, substantive disparities in outcomes by race exist. Many of these disparities are attributed to the decreased use of surgery in non-White patients. Although thymic malignancies are treated by the same specialists as lung and esophageal cancer, it is unknown if there are racial disparities in the treatment of thymic malignancies.

RESEARCH QUESTION

Do racial disparities exist in the surgical treatment of thymic malignancies?

STUDY DESIGN AND METHODS

A retrospective cohort analysis was performed using the National Cancer Data Base of patients diagnosed with thymoma and thymic carcinoma between 2004 and 2016. Univariate comparisons of demographics were compared using χ ² and rank-sum tests. Multivariable analysis was performed to determine if race was an independent variable associated with receiving surgical resection. Preoperative and postoperative care was compared between races.

RESULTS

Seven thousand four hundred eighty-nine patients met inclusion criteria. Four thousand nine hundred sixty-two (66%) were White, 1,311 (18%) were Black, 487 (7%) were Hispanic, 580 (8%) were Asian or Pacific Islander, and 143 (2%) were other races. Black patients with thymic malignancies were more likely to have a median income < $38,000 and not received surgery. Black and Hispanic patients had the lowest median age (54.3 and 53.6 years, respectively) and were most likely to be uninsured (8.2% and 12.5%, respectively). White patients received surgical therapy 1 week sooner and had a postoperative length of stay 1.5 days shorter than Black patients. Multivariable analysis controlling for age, sex, tumor size, insurance status, comorbidity score, histology, and facility type showed that race remained independently associated with the receipt of surgical resection. White patients had the greatest likelihood of receiving surgery with Black patients being least likely to receive surgery (OR, 0.60).

INTERPRETATION

A racial disparity exists in surgical therapy for thymic malignancies.

Early Distant Recurrence in Patients With Resected Stage I Lung Cancer: A Case Series of "Blast Metastasis"

BACKGROUND

The standard of care in the management of stage I non-small-cell lung cancer (NSCLC) has been anatomic lung resection with multistation lymph node sampling of ≥ 10 lymph nodes. The 5-year survival for NSCLC has ranged from 73% to 93% (for stage IB and stage IA, respectively) and will be more favorable for patients with fewer comorbidities and those with a higher state of premorbid functioning and who undergo surgical resection. Despite the positive prognosis for operable stage I NSCLC, a subset of patients will develop metastatic disease within as few as 12 months after resection. Using an institutional database, we have presented the data from 68 patients who had developed distant metastatic recurrence after resection of pathologic stage I NSCLC within 1 year after surgery.

PATIENTS AND METHODS

A retrospective study was conducted of a prospectively maintained intuitional database. The final cohort included patients with pathologic stage I NSCLC who had undergone anatomic resection but had subsequently presented with multiple sites of distant recurrence within 1 year. The study period extended from 2003 to 2020. Patients with broad local recurrence or recurrence at a single distant site were excluded. Kaplan-Meier analysis was used to estimate the 5-year survival.

RESULTS

A total of 2827 patients had undergone surgical resection for stage I NSCLC during the 17-year period and 68 met the criteria for inclusion. Most of the patients (n = 48) were smokers, and the dominant histologic type was adenocarcinoma (n = 37). After recurrence, 22 patients (33%) had undergone chemoradiotherapy and 19 (28%) had received chemotherapy alone. The mean and median overall survival were 23.7 and 14 months, respectively. The 5-year survival from recurrence and surgery were both 13.2%.

CONCLUSIONS

Limited data are available on the risk factors for early metastasis after resected stage I NSCLC. The results from our cohort have demonstrated poor survival after recurrence. These data might be the basis for determining a phenotype for patients prone to early widespread metastasis despite seemingly curative surgical resection.

Racial disparities in local therapy for early stage non-small-cell lung cancer

OBJECTIVES

This study investigated disparities in the delivery of definitive therapy for early stage non-small-cell lung cancer (ESNSCLC) between Caucasian (CS) and African American (AA) populations.

METHODS

The National Cancer Data Base was queried for AA and CS patients, diagnosed with c stage I Non small cell lung cancer between 2004 and 2015. Trends in surgery, stereotactic ablative radiotherapy (SABR), or external beam radiation therapy (EBRT) were compared. Kaplan-Meier and Cox hazards models were used to compare 5-year overall survival (5YOS).

RESULTS

A total of 174,338 (90.6%) patients were CS and 18,077 (9.4%) patients were AA. AA patients were less likely to receive surgery (60.3% vs. 66.9%; p < .001) and more likely to receive EBRT (12.4% vs. 10.6%; p < .001); however, there was no significant difference in rates of SABR (8.8% vs. 9.2%; p = .066). From 2004 to 2015, the surgery rates increased for AA patients from 44.4% to 61.8% and for CS patients from 57.6% to 65.6%. AA patients had worse 5YOS on an unadjusted analysis (46.7% vs. 47.9%; p = .009). When adjusted for definitive treatment, AA patients had improved survival (hazard ratio = 0.97, 95% confidence interval = 0.94-0.99).

CONCLUSION

Improvements in the delivery of surgery and equal utilization of definitive radiation therapy are at least partially responsible for closing the survival gap between AA and CS patients with ESNSCLC.

Resident perception of standardization and credentialing for high-risk bedside procedures in cardiothoracic surgery: Results from an institutional pilot study

OBJECTIVES

Though clear-guidelines are set by the American Board of Thoracic Surgery (ABTS) for the operative cases that cardiothoracic surgery residents must perform to be board-eligible, no such recommendations exist to assess competency for the wide range of high-risk bedside procedures. Our department created and implemented a multidisciplinary course designed to standardize common high-risk bedside procedures and credential our trainees. The aim of this study was to survey the attitudes of residents towards and query the efficacy of such a course.

METHODS

The course was designed with the goal of standardizing endotracheal intubation, arterial line insertion (radial and femoral), central venous line insertion, pigtail tube thoracostomy, thoracentesis and nasogastric tube placement. The course consisted of an online module followed by a 4-hour hands-on simulation session. Knowledge-based pre- and post-evaluations were administered as well as a Likert-based survey regarding multiple aspects of the residents' perceptions of the course and the procedures.

RESULTS

Twenty-three (7 traditional and 16 integrated) cardiothoracic surgical residents participated in the course. Residents reported that 48% of the time, bedside procedures were historically taught by other trainees rather than by faculty. All residents endorsed increased standardization of all procedures after the course. Likewise, residents showed increased confidence in all procedures except for pigtail tube thoracostomy, thoracentesis as well as nasogastric tube placement. 43.5% of the participants demonstrated improvement in the pretest and posttest knowledge-based evaluations.

CONCLUSION

Cardiothoracic residents have favorable attitudes towards standardization and credentialing for high-risk bedside procedures and utilizing such courses may help standardize procedural techniques.

HMGB1 Promotes Myeloid Egress and Limits Lymphatic Clearance of Malignant Pleural Effusions

Pleural effusions, when benign, are attributed to cardiac events and suffusion of fluid within the pleural space. When malignant, lymphatic obstruction by tumor and failure to absorb constitutively produced fluid is the predominant formulation. The prevailing view has been challenged recently, namely that the lymphatics are only passive vessels, carrying antigenic fluid to secondary lymphoid sites. Rather, lymphatic vessels can be a selective barrier, efficiently coordinating egress of immune cells and factors within tissues, limiting tumor spread and immune pathology. An alternative explanation, offered here, is that damage associated molecular pattern molecules, released in excess, maintain a local milieu associated with recruitment and retention of immune cells associated with failed lymphatic clearance and functional lymphatic obstruction. We found that levels of high mobility group box 1 (HMGB1) were equally elevated in both benign and malignant pleural effusions (MPEs) and that limited diversity of T cell receptor expressing gamma and delta chain were inversely associated with these levels in MPEs. Acellular fluid from MPEs enhanced γδ T cell proliferation in vitro, while inhibiting cytokine production from γδ T cells and monocytes as well as restricting monocyte chemotaxis. Novel therapeutic strategies, targeting HMGB1 and its neutralization in such effusions as well as direct delivery of immune cells into the pleural space to reconstitute normal physiology should be considered.

An analysis of analgesia and opioid prescribing for veterans after thoracic surgery

The opioid crisis is a public health issue and has been linked to physician overprescribing. Pain management after thoracic surgery is not standardized at many centers, and we hypothesized that excessive narcotics were being dispensed on discharge. As a quality improvement initiative, we sought to understand current prescribing practices to better align the amount of opioids dispensed on discharge to actual patient needs. This was a single-center, retrospective review of patients undergoing thoracic surgery from 7/2015 to 7/2018. Demographics, operative data, perioperative pain medication use, and discharge pain medication prescriptions were analyzed. Opioids were converted to Morphine Milligram Equivalents (MME). Among 124 patients, 103 (83%) received intraoperative nerve blocks and 106 (85.5%) used PCAs. Prescribed MME/day at discharge were significantly higher than MME/day received during hospitalization (Median 30 [IQR 30–45] vs. 15 [IQR 5–24], p < 0.001) and were not associated with receiving a nerve block or PCA. By procedure, prescribed MME/day were significantly higher than inpatient MME/day for wedge resections (p < 0.001), segmentectomies (p = 0.02), lobectomies (p = 0.003), and thymectomies (p = 0.02). Patients are being discharged with significantly more opioids than they are using as inpatients. Education among prescribers and a standardized approach with patient-specific dosing may reduce excessive opioid dispensing.

Factors Associated With Survival in Complete Pathologic Response Non-Small Cell Lung Cancer

OBJECTIVES

There is a strong association with improved survival for patients with non-small cell lung cancer (NSCLC) who have developed a pathological complete response (pCR) after neoadjuvant therapy. A national database was used to investigate factors associated with long-term survival in this cohort of patients.

PATIENTS

Retrospective review was completed of the National Cancer Database of patients who obtained pCR and had neoadjuvant therapy for stage I to stage III NSCLC between 2004 and 2014. All patients had neoadjuvant chemotherapy with or without radiation therapy.

METHODS

Univariate and multivariable analysis was performed on factors associated with overall survival (OS), including gender, clinical stage, and nodal count. Patients were divided into 2 groups based on the Commission on Cancer-recommended median number of lymph nodes (LNs) examined: 0 to 9 LNs and ≥10 LNs. Chi-square and Wilcoxon rank-sum tests were used to compare patient, hospital, and clinical variables between groups.

RESULTS

Increased age (hazard ratio [HR] 1.02, 95% confidence interval [CI], 1.00-1.03), neoadjuvant radiation therapy (HR 1.48, 95% CI, 1.10-2.00), and pneumonectomy (HR 1.64, 95% CI, 1.22-2.22) were associated with worse survival in the 759-patient cohort. Multivariable regression demonstrated having ≥10 nodes harvested (HR 0.71, 95% CI, 0.56-0.89) was associated with improved survival as was every increase in LN harvest up to 17 LNs. No significant differences in 5-year OS were found between clinical stage I, II, and III, respectively (66.1% vs. 60.9% vs. 58.6%, P = .288).

CONCLUSION

This study shows that younger age, increasing LN harvest, female sex, the absence of neoadjuvant radiation therapy and non-pneumonectomy resections are all associated with improved OS in patients with NSCLC who have developed pCR.

Delayed Chylothorax during Treatment of Follicular Lymphoma with a Malignant Pleural Effusion

Chylothorax occurs following dysfunction or disruption of the lymphatic drainage along the thoracic duct. Malignant and traumatic causes account for the majority of these occurrences, with lymphoma accounting for 11-37% of chylothoraces. The clinical course of chylothorax may include dehydration, malnutrition, immunosuppression, electrolyte disturbances, infection, and ultimately death. Management of chylothorax is patient-specific and is based on etiology and surgeon experience. Initially, most chyle leaks are managed with nonoperative strategies, such as gut rest, hyperalimentation, and pleural drainage, and, at times, medium-chained fatty acid diet or octreotide, with hopes to decrease chyle production (Zabeck et al. (2011)). High-output chyle leaks following iatrogenic injury or trauma are commonly managed with thoracic duct ligation. Lymphangiography with or without thoracic duct embolization has become increasingly popular and efficacious with the possible benefit of less morbidity (Cope et al. (2002)). We report a case of a 61-year-old male with delayed chylothorax while having an indwelling pleural catheter for malignant pleural effusion during treatment of follicular lymphoma. Percutaneous thoracic duct embolization was attempted but was unsuccessful. Chemotherapy, fluid management, and nutritional support allowed this to resolve over the course of ninety days from diagnosis. We describe the patient's clinical course and highlight nonoperative management of delayed chylothorax in the setting of follicular lymphoma treatment.

Sublobar resection is associated with decreased survival for patients with early stage large-cell neuroendocrine carcinoma of the lung

OBJECTIVES

Sublobar resection (SLR) for early non-small-cell lung carcinoma (NSCLC) has been shown to have a survival rate similar to that of lobectomy. Large-cell neuroendocrine carcinoma (LCNEC) of the lung, although treated like an NSCLC, has a poor prognosis compared to NSCLC. We sought to determine if outcomes are poor in patients with early stage LCNEC treated with SLR versus lobectomy.

METHODS

We searched for patients with pathological stage I LCNEC ≤3 cm within the National Cancer Database between 2004 and 2014. Propensity score matching was used to compare the 5-year overall survival rate of patients having SLR (wedge or segmentectomy) to that of patients having a lobectomy. Patients were matched for age, node sampling, comorbidity score, tumour size, insurance status and other factors. Patients who received neoadjuvant therapy were excluded. Kaplan-Meier methods were used for analysis.

RESULTS

A total of 1011 patients met the inclusion criteria: 263 were treated with SLR (223 wedges and 40 segmentectomies) and 748 patients, with lobectomy. Patients who received SLR were older, had more comorbidities and smaller tumours. On unadjusted Kaplan-Meier analysis, patients who had SLR had decreased 5-year overall survival compared to those who had a lobectomy (37.9% vs 56.6%, P < 0.001). Propensity score matching (1:1) across 12 demographic and tumour variables yielded 185 patients per group with 34 segmentectomies and 151 wedge resections in the SLR cohort. On Kaplan-Meier analysis of the matched cohort, patients who had SLR had a worse 5-year overall survival rate compared to those who had a lobectomy (41.5% vs 60.3%; P = 0.001).

CONCLUSIONS

SLR for early stage LCNEC is associated with a lower 5-year overall survival rate compared to lobectomy on unadjusted and propensity matched analyses.

Higher lymph node harvest in patients with a pathologic complete response after neoadjuvant therapy for esophageal cancer is associated with improved survival

BACKGROUND AND OBJECTIVES

Lymph node harvest during esophagectomy has been associated with improved survival for esophageal cancer but the value of enhanced lymph node harvest following complete pathologic response (pCR) is debated. This study investigated if increasing lymph node harvest in esophageal cancer patients with a pCR after neoadjuvant therapy and esophagectomy is associated with improved survival.

METHODS

We queried the National Cancer Data Base for patients with esophageal cancer between 2004 and 2014 who underwent neoadjuvant chemotherapy or chemoradiation therapy followed by esophagectomy found to have pCR. Multivariable Cox modeling was utilized to evaluate the impact of increasing lymph node counts on overall survival (OS).

RESULTS

A total of 1373 patients met inclusion criteria. A National Comprehensive Cancer Network compliant lymphadenectomy of ≥15 nodes was associated with improved survival (66.7% vs 51.1%; P < .001). Cox modeling showed that the first node cutoff to demonstrate a statistically significant improvement in OS was ≥7 nodes (hazard ratio [HR], 95% confidence interval [CI]: 0.81, 0.68-0.97; 5-year OS: 54.2%) with a trend of decreasing and statistically significant HRs until ≥25 nodes (HR, 95% CI: 0.52, 0.37-0.72; 5-year OS: 68.4%).

CONCLUSIONS

High negative node counts after neoadjuvant therapy and esophagectomy are associated with improved survival in patients with pCR.

Association of Preoperative Patient Frailty and Operative Stress With Postoperative Mortality

Importance

Patients with frailty have higher risk for postoperative mortality and complications; however, most research has focused on small groups of high-risk procedures. The associations among frailty, operative stress, and mortality are poorly understood.

Objective

To assess the association between frailty and mortality at varying levels of operative stress as measured by the Operative Stress Score, a novel measure created for this study.

Design, Setting, and Participants

This retrospective cohort study included veterans in the Veterans Administration Surgical Quality Improvement Program from April 1, 2010, through March 31, 2014, who underwent a noncardiac surgical procedure at Veterans Health Administration Hospitals and had information available on vital status (whether the patient was alive or deceased) at 1 year postoperatively. A Delphi consensus method was used to stratify surgical procedures into 5 categories of physiologic stress.

Exposures

Frailty as measured by the Risk Analysis Index and operative stress as measured by the Operative Stress Score.

Main Outcomes and Measures

Postoperative mortality at 30, 90, and 180 days.

Results

Of 432 828 unique patients (401 453 males [92.8%]; mean (SD) age, 61.0 [12.9] years), 36 579 (8.5%) were frail and 9113 (2.1%) were very frail. The 30-day mortality rate among patients who were frail and underwent the lowest-stress surgical procedures (eg, cystoscopy) was 1.55% (95% CI, 1.20%-1.97%) and among patients with frailty who underwent the moderate-stress surgical procedures (eg, laparoscopic cholecystectomy) was 5.13% (95% CI, 4.79%-5.48%); these rates exceeded the 1% mortality rate often used to define high-risk surgery. Among patients who were very frail, 30-day mortality rates were higher after the lowest-stress surgical procedures (10.34%; 95% CI, 7.73%-13.48%) and after the moderate-stress surgical procedures (18.74%; 95% CI, 17.72%-19.80%). For patients who were frail and very frail, mortality continued to increase at 90 and 180 days, reaching 43.00% (95% CI, 41.69%-44.32%) for very frail patients at 180 days after moderate-stress surgical procedures.

Conclusions and Relevance

We developed a novel operative stress score to quantify physiologic stress for surgical procedures. Patients who were frail and very frail had high rates of postoperative mortality across all levels of the Operative Stress Score. These findings suggest that frailty screening should be applied universally because low- and moderate-stress procedures may be high risk among patients who are frail.

Neuropilin-2 Isoforms Regulate Distinct Functions of Tumor-associated Macrophages in Breast Cancer

Introduction

Neuropilins are neural guidance molecules which contribute to tissue development. We have shown that the two isoforms of neuropilin-2 endow opposing functionality to tumor cells due to distinct signaling pathways, with Nrp2b promoting metastatic behavior. Due to the role of macrophages (Mθ) in organogenesis and metastasis, we examine the role of Nrp2 isoforms in these cells.

Methods

Stable shRNA knockdown of Nrp2a or Nrp2b in Raw264.7 Mθ were generated. Phagocytosis, cytokine production, and migration were assessed in knockdowns in response to stimuli (TGFβ, HGF, VEGF, IL-10, IFNγ, LPS, β-glucan). Nrp2 isoforms in Mθ from mouse mammary tissue or EO771-induced mammary tumors were measured by FACS and RT-PCR. Mθ were phenotyped via FACS for wound-healing or inflammatory markers. Single-cell (sc)qPCR for a 96 gene panel examining components of signaling pathways, autophagy, metabolism, and pro/anti-tumor responses was performed on 576 CD11b+F4/80+ TAMs FACS-sorted from EO771 tumors.

Results

Nrp2b expression was significantly upregulated in TAMs compared to Mθ of the blood, spleen, or mammary tissues. 56% of the scqPCR transcripts analyzed were significantly altered in Nrp2bHigh vs. Nrp2bLow TAMs, and computation analysis (PCA/tSNE) revealed two distinct TAM subsets enriched for Nrp2b. Nrp2b+ Raw264.7 cells showed decreased ability to phagocytose tumor cells, but increased rates of division and migration in response to growth factors compared to Nrp2a+ counterparts.

Conclusions

We demonstrate, for the first time, that the principle neuropilin-2 isoforms are present in Mθ, regulate unique functionality, and that Nrp2b+ TAMs are both upregulated in mammary tumors and represent a phenotypically unique subtype.

Treatment of malignant pleural effusions: the case for localized immunotherapy

Malignant pleural effusions (MPE) are a common terminal pathway for many cancers, with an estimated United States incidence of more than 150,000 cases per year. MPE is an aggressive disease with a uniformly fatal prognosis and a life expectancy of only 3 to 12 months. The development of an effective targeted therapy represents a pressing unmet need. This commentary focuses on how cellular and humoral components condition the pleural space as a tumor-promoting, wound-healing environment. Despite an abundance of potential antigen presenting and effector cells in the pleura, their physical isolation by the mesothelial barrier, the concentration of cytokines and chemokines driving the epithelial to mesenchymal transition (EMT) and M2 /Th-2 polarization, suppress tumor-specific immune effector responses. We argue that local immune repolarization must precede either immune checkpoint or cellular therapy to successfully eradicate pleural tumor. We further hypothesize that, because of its cellular content, a repolarized pleural space will provide an effective immune environment for generation of systemic anti-tumor response.

Node-Positive Segmentectomy for Non-Small-Cell Lung Cancer: Risk Factors and Outcomes

BACKGROUND

Segmentectomy for well-selected early stage non-small-cell lung carcinoma (NSCLC) has been shown to have similar oncologic outcomes and survival to lobectomy. However, these data are based on the presumption that the disease is node negative. Few data exist regarding the risk factors for and the outcomes of patients with disease treated with segmentectomy that is found to be node positive. We sought to determine the risk factors for and outcomes of clinical stage I NSCLC patients who are treated with segmentectomy but are determined to be node positive.

PATIENTS AND METHODS

We queried patients with clinical stage I NSCLC ≤ 3 cm within the National Cancer Data Base between 2004 and 2014 who were treated with segmentectomy or lobectomy and found to have positive nodes. Kaplan-Meier curves with log-rank tests were used to compare overall survival (OS) between segmentectomy and lobectomy. For comparison only, segmentectomy patients with pathologically node-negative disease were identified to determine predictors of node positivity after segmentectomy via multivariable logistic regression.

RESULTS

A total of 4556 patients with node-positive disease were identified, comprising 115 segmentectomy patients and 4441 lobectomy patients. Multivariable analysis identified increasing tumor size, squamous-cell histology, and increasing number lymph nodes sampled as significant predictors of node positivity after segmentectomy. There was no difference in OS between segmentectomy and lobectomy, with 3-year OS rates of 66.3% and 68.1%, respectively (P = .723).

CONCLUSION

There are discrete risk factors for discovering positive nodes after segmentectomy. Segmentectomy is associated with similar OS compared to lobectomy for clinical stage I NSCLC found to be node positive.

Making cold malignant pleural effusions hot: driving novel immunotherapies

Malignant pleural effusions, arising from either primary mesotheliomas or secondary malignancies, heralds advanced disease and poor prognosis. Current treatments, including therapeutic thoracentesis and tube thoracostomy, are largely palliative. The immunosuppressive environment within the pleural cavity includes myeloid derived suppressor cells, T-regulatory cells, and dysfunctional T cells. The advent of effective immunotherapy with checkpoint inhibitors and adoptive cell therapies for lung cancer and other malignancies suggests a renewed examination of local and systemic therapies for this malady. Prior strategies reporting remarkable success, including instillation of the cytokine interleukin-2, perhaps coupled with checkpoint inhibitors, should be further evaluated in the modern era.

Outcomes after endoscopic mucosal resection or esophagectomy for submucosal esophageal adenocarcinoma

OBJECTIVES

Endoscopic mucosal resection (EMR) is a diagnostic and potentially therapeutic option for patients with submucosal esophageal adenocarcinoma. However, there are significant concerns regarding the risk of lymph node metastasis. Our purpose was to construct a comparative effectiveness analysis comparing recurrence patterns after therapeutic EMR or esophagectomy.

METHODS

Patients who underwent therapeutic EMR or esophagectomy from 2007 to 2015 with pathologically staged submucosal adenocarcinoma were identified from a departmental database. Cancer-related outcomes were compared among an unmatched as well as a propensity matched cohort. Risk stratification was also used to compare results among those with a low, medium, or high risk of nodal metastasis.

RESULTS

Seventy-two patients met criteria for analysis, among whom 23 underwent therapeutic EMR with esophageal preservation and 49 underwent esophagectomy. Median follow-up was 43 months. Patients who underwent esophagectomy had larger, deeper tumors. Esophageal preservation was associated with an increased risk of local recurrence (P = .01), but not distant recurrence (P = .44). After propensity matching, there continued to be no difference in distant recurrence rate (P = .66). In a risk-stratified analysis, low-risk patients showed no recurrences or cancer-related deaths, however, high-risk patients showed a trend toward increased distant recurrence after therapeutic EMR.

CONCLUSIONS

Esophageal preservation after therapeutic EMR was associated with an increased risk of local recurrence. Among low-risk patients, either strategy resulted in excellent cancer control. However, among high-risk patients, esophageal preservation showed a trend toward increased distant failure. These findings should prompt further investigation to determine optimal treatment for patients with submucosal esophageal adenocarcinoma.

Targeting Immune Checkpoints in Esophageal Cancer: A High Mutational Load Tumor

Checkpoint inhibitors (eg, programmed cell death protein 1 [PD-1], programmed cell death ligand 1 [PD-L1], cytotoxic T-lymphocyte associated protein 4 [CTLA-4] antibodies) are changing how we understand cancer and provide a means to develop modern immunotherapies. An emergent notion relates success with checkpoint inhibitors with high mutational load tumors. There are few studies that examine checkpoint protein expression and relate these to clinical outcomes after the conventional treatment of patients with esophageal cancer, which has a high mutational load. The objective of this review is to summarize the literature that examines checkpoint expression and clinical outcomes, as well as propose an accelerated approach to introducing these therapies into the clinic to treat patients with esophageal cancer.

5-Fluorouracil upregulates cell surface B7-H1 (PD-L1) expression in gastrointestinal cancers

Background

Resistance to chemotherapy is a major obstacle in the effective treatment of cancer patients. B7-homolog 1, also known as programmed death ligand-1 (PD-L1), is an immunoregulatory protein that is overexpressed in several human cancers. Interaction of B7-H1 with programmed death 1 (PD-1) prevents T-cell activation and proliferation, sequestering the T-cell receptor from the cell membrane, inducing T-cell apoptosis, thereby leading to cancer immunoresistance. B7-H1 upregulation contributes to chemoresistance in several types of cancer, but little is known with respect to changes associated with 5-fluorouracil (5-FU) or gastrointestinal cancers.

Methods

HCT 116 p53^+/+, HCT 116 p53^−/− colorectal cancer (CRC) and OE33 esophageal adenocarcinoma (EAC) cells were treated with increasing doses of 5-FU (0.5 uM, 5 uM, 50 uM, 500 uM) or interferon gamma (IFN-γ, 10 ng/mL) in culture for 24 h and B7-H1 expression was quantified using flow cytometry and western blot analysis. We also evaluated B7-H1 expression, by immunohistochemistry, in tissue collected prior to and following neoadjuvant therapy in 10 EAC patients.

Results

B7-H1 expression in human HCT 116 p53^+/+ and HCT 116 p53^−/− CRC cells lines, while low at baseline, can be induced by treatment with 5-FU. OE33 baseline B7-H1 expression exceeded CRC cell maximal expression and could be further increased in a dose dependent manner following 5-FU treatment in the absence of immune cells. We further demonstrate tumor B7-H1 expression in esophageal adenocarcinoma patient-derived pre-treatment biopsies. While B7-H1 expression was not enhanced in post-treatment esophagectomy specimens, this may be due to the limits of immunohistochemical quantification.

Conclusions

B7-H1/PD-L1 expression can be increased following treatment with 5-FU in gastrointestinal cancer cell lines, suggesting alternative mechanisms to classic immune-mediated upregulation. This suggests that combining 5-FU treatment with PD-1/B7-H1 blockade may improve treatment in patients with gastrointestinal adenocarcinoma.

Endoscopic Ultrasound Estimates for Tumor Depth at the Gastroesophageal Junction Are Inaccurate: Implications for the Liberal Use of Endoscopic Resection

BACKGROUND

Endoscopic resection is increasingly utilized for treating early stage esophageal cancer, and endoscopic ultrasound (EUS) frequently guides treatment selection. Studies report greater than 80% sensitivity and 90% specificity, but our experience suggests less accuracy at the gastroesophageal (GE) junction. The objective of this study is to determine the accuracy of EUS for depth of GE junction cancer and the potential treatment implications.

METHODS

A retrospective review of a prospective database was performed for patients from 1995 to 2014 with GE junction esophageal cancer that underwent EUS staging and resection (surgical or endoscopic) without neo-adjuvant therapy. Patient, tumor, EUS, and pathologic characteristics were examined.

RESULTS

For the 181 patients that met criteria, the median age was 66 years, 17% were female, 91% white, and 98% had adenocarcinoma. Concordance between EUS (u) T and pathologic (p) T was 48%, with 23% under-staged and 29% over-staged. The EUS was accurate in the following: uT0 6% (1 of 18); uT1a 56% (23 of 41); uT1b 58% (41 of 71); uT2 10% (2 of 21); and uT3 70% (21 of 30). Inaccurate EUS depth had potential to lead to over-treatment in 38% (27 of 71) of uT1b and 76% (16 of 21) of uT2. In 50% of pT1a tumors, EUS depth was T1b or greater. Logistic regression revealed tumor length (continuous variable) to be associated with inaccurate uT (p = 0.016). Accurately staged tumors were significantly longer than inaccurately staged tumors (2.7 vs 1.7 cm, p = 0.011).

CONCLUSIONS

Early to intermediate GE junction tumors are frequently over-staged. This highlights the importance of diagnostic endoscopic resection for determining accurate tumor depth and selecting correct therapy.

Concordance of studies for nodal staging is prognostic for worse survival in esophageal cancer

Pretreatment clinical staging in esophageal cancer influences prognosis and treatment strategy. Current staging strategies utilize multiple imaging modalities, and often the results are contradictory. No studies have examined the implications of concordance of computed tomography (CT), positron emission tomography (PET), and endoscopic ultrasound (EUS) when used for the evaluation of nodal disease. The objective of this study was to determine if concordance of CT, PET, or EUS for nodal disease predicts worse overall survival. We reviewed 615 esophageal cancer patients with pretreatment CT, PET, and EUS that underwent esophagectomy for survival outcomes based on concordance of studies for nodal disease. Concordant N+ is defined as two or three studies positive for nodal disease; non-concordant N+ is defined as only one positive study. Node-positive disease by any study predicted shorter survival than node-negative disease (42% vs. 73% 5-year survival; P<0.001). Additionally, non-concordant N+ patients had shorter survival than N- patients (52% vs. 73% 5-year survival; P<0.001). Concordant N+ patients had shorter survival than non-concordant N+ patients (38- vs. 61-month median survival; P=0.017). There were no statistically significant differences in survival based on specific combinations of studies. When PET was disregarded, patients with both CT+ and EUS+ had shorter survival than patients with either CT+ or EUS+ (39- vs. 58-month median survival; P=0.029). Pretreatment CT, PET, or EUS concordance for node-positive disease predicts shorter overall survival in patients that undergo esophagectomy for esophageal cancer. Predicting survival in esophageal cancer should consider the synergistic capabilities of CT, PET, and EUS in evaluating nodal status.

Interferon regulatory factor-2 is protective against hepatic ischemia-reperfusion injury

Interferon regulatory factor (IRF)-1 is a nuclear transcription factor that induces inflammatory cytokine mediators and contributes to hepatic ischemia-reperfusion (I/R) injury. No strategies to mitigate IRF1-mediated liver damage exist. IRF2 is a structurally similar endogenous protein that competes with IRF1 for DNA binding sites in IRF-responsive target genes and acts as a competitive inhibitor. However, the role of IRF2 in hepatic injury during hypoxic or inflammatory conditions is unknown. We hypothesize that IRF2 overexpression may mitigate IRF1-mediated I/R damage. Endogenous IRF2 is basally expressed in normal livers and is mildly increased by ischemia alone. Overexpression of IRF2 protects against hepatic warm I/R injury. Furthermore, we demonstrate that IRF2 overexpression limits production of IRF1-dependent proinflammatory genes, such as IL-12, IFNβ, and inducible nitric oxide synthase, even in the presence of IRF1 induction. Additionally, isograft liver transplantation with IRF2 heterozygote knockout (IRF2(+/-)) donor grafts that have reduced endogenous IRF2 levels results in worse injury following cold I/R during murine orthotopic liver transplantation. These findings indicate that endogenous intrahepatic IRF2 protein is protective, because the IRF2-deficient liver donor grafts exhibited increased liver damage compared with the wild-type donor grafts. In summary, IRF2 overexpression protects against I/R injury by decreasing IRF1-dependent injury and may represent a novel therapeutic strategy.