Predicting Severe Complications from Cytoreductive Surgery with Hyperthermic Intraperitoneal Chemotherapy: A Data-Driven, Machine Learning Approach to Augment Clinical Judgment

BACKGROUND

CRS-HIPEC provides oncologic benefit in well-selected patients with peritoneal carcinomatosis; however, it is a morbid procedure. Decision tools for preoperative patient selection are limited. We developed a risk score to predict severity of 90 day complications for cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC).

PATIENTS AND METHODS

Adults who underwent CRS-HIPEC at the University of Pittsburgh Medical Center (March 2001-April 2020) were analyzed as part of this study. Primary endpoint was severe complications within 90 days following CRS-HIPEC, defined using Comprehensive Complication Index (CCI) scores as a dichotomous (determined using restricted cubic splines) and continuous variable. Data were divided into training and test sets. Several machine learning and traditional algorithms were considered.

RESULTS

For the 1959 CRS-HIPEC procedures included, CCI ranged from 0 to 100 (median 32.0). Adjusted restricted cubic splines model defined severe complications as CCI > 61. A minimum of 20 variables achieved optimal performance of any of the models. Linear regression achieved the highest area under the receiving operator characteristic curve (AUC, 0.74) and outperformed the NSQIP Surgical Risk calculator (AUC 0.80 vs. 0.66). Factors most positively associated with severe complications included peritoneal carcinomatosis index score, symptomatic status, and undergoing pancreatectomy, while American Society of Anesthesiologists 2 class, appendiceal diagnosis, and preoperative albumin were most negatively associated with severe complications.

CONCLUSIONS

This study refines our ability to predict severe complications within 90 days of discharge from a hospitalization in which CRS-HIPEC was performed. This advancement is timely and relevant given the growing interest in this procedure and may have implications for patient selection, patient and referring provider comfort, and survival.

Comprehensive Cost Implications of Commercially Available Noninvasive Colorectal Cancer Screening Modalities

BACKGROUND

There is an increasing usage of noninvasive screening modalities for colorectal cancer (CRC), primarily the fecal immunochemical test (FIT) and multi-target stool DNA test (Cologuard [CG]). The aim of this study was to determine the comprehensive, long-term cost implications of these noninvasive screening modalities.

STUDY DESIGN

Using a national insurer-based administrative dataset, patients screened for CRC from January 1, 2019 to December 31, 2019 were analyzed. A hierarchical logic system was used to determine the primary screening modality for each patient. The total annual costs in US dollars ($) were extrapolated using number of patients screened, costs per test, screening intervals, and costs incurred from false results. Patients within our tumor registry diagnosed with CRC were matched to their claims data, and cancer stage distribution was compared.

RESULTS

Of 119,334 members who underwent noninvasive screening, 38.1% underwent screening with FIT and 40.0% with CG. The combined annual cost for these 2 screening modalities was $13.7 million. By transitioning to FIT alone for all noninvasive screening, the total annual cost would decrease to $7.9 million, resulting in a savings of approximately $5.8 million per year. Additionally, by combining data from the network cancer registry and insurer-based claims dataset, we were able to match 533 individuals who underwent screening and were later diagnosed with CRC. The rate of early-stage (stage 0 to II) disease was found to be similar between those screened with FIT and CG (59.5% FIT vs 63.2% CG; p = 0.77).

CONCLUSIONS

The adoption of FIT as the primary noninvasive CRC screening method has the potential to generate significant cost savings, and therefore, carries significant value implications for a large population health system.

Impact of Primary Tumor Location and Genomic Alterations on Survival Following Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemoperfusion for Colorectal Peritoneal Metastases

BACKGROUND

Colorectal cancer leads to peritoneal metastases (CRPM) in 10% of cases. Cytoreductive surgery with hyperthermic intraperitoneal chemoperfusion (CRS-HIPEC) improves survival. Primary tumor location and abnormalities in RAS, BRAF, and mismatch repair/microsatellite stability (MMR/MSI) may affect post-CRS-HIPEC survival, but studies have not been consistent. We estimated the effects of primary tumor site and genomic alterations on post-CRS-HIPEC survival.

METHODS

This retrospective cohort study included CRS-HIPEC cases for CRPM at a high-volume center from 2001 to 2020. Next-generation sequencing and microsatellite testing defined the RAS, BRAF, and MMR/MSI genotypes. Adjusted effects of tumor sidedness and genomics on survival were evaluated using a multivariable Cox proportional hazards model. We analyzed these variables' effects on progression-free survival and the effects of immune checkpoint-inhibitors.

RESULTS

A total of 250 patients underwent CRS-HIPEC with testing for RAS, BRAF, and MMR/MSI; 50.8% of patients were RAS-mutated, 12.4% were BRAF-mutated, and 6.8% were deficient-MMR/MSI-high (dMMR/MSI-H). Genomic alterations predominated in right-sided cancers. After adjustment for comorbidities and oncological and perioperative variables, rectal origin [hazard ratio (HR) 1.9, p = 0.01], RAS mutation (HR 1.6, p = 0.01), and BRAF mutation (HR 1.7, p = 0.05) were associated with worse survival. RAS mutation was also associated with shorter progression-free survival (HR 1.6, p = 0.01 at 6 months post-operatively), and dMMR/MSI-H status was associated with superior survival (HR 0.3, p = 0.01 at 2 years). dMMR/MSI-H patients receiving immune checkpoint-inhibitors trended toward superior survival.

CONCLUSIONS

Rectal origin, RAS mutations, and BRAF mutations are each associated with poorer survival after CRS-HIPEC for CRPM. Patients with CRPM and dMMR/MSI-H status have superior survival. Further research should evaluate benefits of immune checkpoint-inhibitors in this subgroup.

Elucidating the heterogeneity of immunotherapy response and immune-related toxicities by longitudinal ctDNA and immune cell compartment tracking in lung cancer

Purpose

Although immunotherapy is the mainstay of therapy for advanced non-small cell lung cancer (NSCLC), robust biomarkers of clinical response are lacking. The heterogeneity of clinical responses together with the limited value of radiographic response assessments to timely and accurately predict therapeutic effect -especially in the setting of stable disease-call for the development of molecularly-informed real-time minimally invasive predictive biomarkers. In addition to capturing tumor regression, liquid biopsies may be informative in evaluating immune-related adverse events (irAEs).

Experimental design

We investigated longitudinal changes in circulating tumor DNA (ctDNA) in patients with metastatic NSCLC who received immunotherapy-based regimens. Using ctDNA targeted error-correction sequencing together with matched sequencing of white blood cells and tumor tissue, we tracked serial changes in cell-free tumor load (cfTL) and determined molecular response for each patient. Peripheral T-cell repertoire dynamics were serially assessed and evaluated together with plasma protein expression profiles.

Results

Molecular response, defined as complete clearance of cfTL, was significantly associated with progression-free (log-rank p=0.0003) and overall survival (log-rank p=0.01) and was particularly informative in capturing differential survival outcomes among patients with radiographically stable disease. For patients who developed irAEs, peripheral blood T-cell repertoire reshaping, assessed by significant TCR clonotypic expansions and regressions were noted on-treatment.

Conclusions

Molecular responses assist with interpretation of heterogeneous clinical responses especially for patients with stable disease. Our complementary assessment of the tumor and immune compartments by liquid biopsies provides an approach for monitoring of clinical benefit and immune-related toxicities for patients with NSCLC receiving immunotherapy.

Statement of translational relevance

Longitudinal dynamic changes in cell-free tumor load and reshaping of the peripheral T-cell repertoire capture clinical outcomes and immune-related toxicities during immunotherapy for patients with non-small cell lung cancer.

A maladaptive pleural environment suppresses preexisting anti-tumor activity of pleural infiltrating T cells

Introduction

Treatment options for patients with malignant pleural effusions (MPE) are limited due, at least in part, to the unique environment of the pleural space, which drives an aggressive tumor state and governs the behavior of infiltrating immune cells. Modulation of the pleural environment may be a necessary step toward the development of effective treatments. We examine immune checkpoint molecule (ICM) expression on pleural T cells, the secretomes of pleural fluid, pleural infiltrating T cells (PIT), and ability to activate PIT ex vivo.

Methods

ICM expression was determined on freshly drained and in vitro activated PIT from breast, lung and renal cell cancer. Secretomics (63 analytes) of activated PIT, primary tumor cultures and MPE fluid was determined using Luminex technology. Complementary digital spatial proteomic profiling (42 analytes) of CD45+ MPE cells was done using the Nanostring GeoMx platform. Cytolytic activity was measured against autologous tumor targets.

Results

ICM expression was low on freshy isolated PIT; regulatory T cells (T-reg) were not detectable by GeoMx. In vitro activated PIT coexpressed PD-1, LAG-3 and TIGIT but were highly cytotoxic against autologous tumor and uniquely secreted cytokines and chemokines in the > 100 pM range. These included CCL4, CCL3, granzyme B, IL-13, TNFα, IL-2 IFNγ, GM-CSF, and perforin. Activated PIT also secreted high levels of IL-6, IL-8 and sIL-6Rα, which contribute to polarization of the pleural environment toward wound healing and the epithelial to mesenchymal transition. Addition of IL-6Rα antagonist to cultures reversed tumor EMT but did not alter PIT activation, cytokine secretion or cytotoxicity.

Discussion

Despite the negative environment, immune effector cells are plentiful, persist in MPE in a quiescent state, and are easily activated and expanded in culture. Low expression of ICM on native PIT may explain reported lack of responsiveness to immune checkpoint blockade. The potent cytotoxic activity of activated PIT and a proof-of-concept clinical scale GMP-expansion experiment support their promise as a cellular therapeutic. We expect that a successful approach will require combining cellular therapy with pleural conditioning using immune checkpoint blockers together with inhibitors of upstream master cytokines such as the IL-6/IL-6R axis.

A Real-Time Mobile Intervention to Reduce Sedentary Behavior Before and After Cancer Surgery: Pilot Randomized Controlled Trial

BACKGROUND

Sedentary behavior (SB) is prevalent after abdominal cancer surgery, and interventions targeting perioperative SB could improve postoperative recovery and outcomes. We conducted a pilot study to evaluate the feasibility and preliminary effects of a real-time mobile intervention that detects and disrupts prolonged SB before and after cancer surgery, relative to a monitoring-only control condition.

OBJECTIVE

Our aim was to evaluate the feasibility and preliminary effects of a perioperative SB intervention on objective activity behavior, patient-reported quality of life and symptoms, and 30-day readmissions.

METHODS

Patients scheduled for surgery for metastatic gastrointestinal cancer (n=26) were enrolled and randomized to receive either the SB intervention or activity monitoring only. Both groups used a Fitbit smartwatch and companion smartphone app to rate daily symptoms and collect continuous objective activity behavior data starting from at least 10 days before surgery through 30 days post discharge. Participants in the intervention group also received prompts to walk after any SB bout that exceeded a prespecified threshold, with less frequent prompts on days that patients reported more severe symptoms. Participants completed end-of-study ratings of acceptability, and we also examined adherence to assessments and to walking prompts. In addition, we examined effects of the intervention on objective SB and step counts, patient-reported quality of life and depressive and physical symptoms, as well as readmissions.

RESULTS

Accrual (74%), retention (88%), and acceptability ratings (mean overall satisfaction 88.5/100, SD 9.1) were relatively high. However, adherence to assessments and engagement with the SB intervention decreased significantly after surgery and did not recover to preoperative levels after postoperative discharge. All participants exhibited significant increases in SB and symptoms and decreases in steps and quality of life after surgery, and participants randomized to the SB intervention unexpectedly had longer maximum SB bouts relative to the control group. No significant benefits of the intervention with regard to activity, quality of life, symptoms, or readmission were observed.

CONCLUSIONS

Perioperative patients with metastatic gastrointestinal cancer were interested in a real-time SB intervention and rated the intervention as highly acceptable, but engagement with the intervention and with daily symptom and activity monitoring decreased significantly after surgery. There were no significant effects of the intervention on step counts, patient-reported quality of life or symptoms, and postoperative readmissions, and there was an apparent adverse effect on maximum SB. Results highlight the need for additional work to modify the intervention to make reducing SB and engaging with mobile health technology after abdominal cancer surgery more feasible and beneficial.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03211806; https://tinyurl.com/3napwkkt.

Ferroptosis Inducer Improves the Efficacy of Oncolytic Virus-Mediated Cancer Immunotherapy

Ferroptosis is a type of programmed cell death dependent on iron and characterized by the accumulation of lipid peroxides. In this study, we explore the combination of a ferroptosis activator with an oncolytic vaccinia virus in tumor models. Erastin induced cell death in hepatoma, colon, and ovarian cancer cells, but not in melanoma cancer cells. Erastin, not the oncolytic vaccinia virus (OVV), induced the expression of key marker genes for ferroptosis in cancer cells. In hepatocellular carcinoma and colon cancer models, either erastin or OVV inhibited tumor growth, but a combination of the two yielded the best therapeutic effects, as indicated by inhibited tumor growth or regression and longer host survival. Immunological analyses indicate that erastin alone had little or no effect on systemic immunity or local immunity in the tumor. However, when combined with OV, erastin enhanced the number of activated dendritic cells and the activity of tumor-infiltrating T lymphocytes as indicated by an increase in IFN-γ⁺CD8⁺ and PD-1⁺CD8⁺ T cells. These results demonstrate that erastin can exert cytotoxicity on cancer cells via ferroptosis, but has little effect on immune activity by itself. However, when combined with an OVV, erastin promoted antitumoral immunity and efficacy by increasing the number of activated dendritic cells and promoting the activities of tumor specific CD8⁺ T cells in the tumor.

Failure to Thrive Following Cytoreduction and Hyperthermic Intraperitoneal Chemotherapy: Causes and Consequences

BACKGROUND

Failure to thrive (FTT) is a complex syndrome of nutritional failure and functional decline. Readmission for FTT following cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS HIPEC) is common but underexamined. This study aims to determine features, risk factors, and prognostic significance of FTT following CRS HIPEC.

PATIENTS AND METHODS

We reviewed patients who underwent CRS HIPEC from 2010 to 2018 at our institution. Patients were categorized into no readmission, FTT readmission, and other readmission. FTT was determined by coding and chart review. We compared baseline characteristics, oncologic data, perioperative outcomes, and survival among the three cohorts.

RESULTS

Of 1068 discharges examined, 379 patients (36%) were readmitted within 90 days, of which 134 (12.5%) were labeled as FTT. Patients with FTT readmission had worse preoperative functional status, higher rates of malnutrition, more complex resections, longer hospital stays, and more postoperative complications (all p < 0.001). Ostomy creation [relative risk ratio (RRR) 4.06], in-hospital venous thromboembolism (VTE), discharge to nursing home (RRR 2.48), pre-CRS HIPEC chemotherapy (RRR 1.98), older age (RRR 1.84), and female gender (RRR 1.69) were all independent predictors for FTT readmission on multinomial regression (all p < 0.01). FTT readmission was associated with worse median overall survival on multivariate analysis [hazard ratio (HR) 1.60, p < 0.001] after controlling for oncologic, perioperative, and baseline factors.

CONCLUSIONS

FTT is common following CRS HIPEC and appears to be associated with baseline patient characteristics, operative burden, and postoperative complications. Perioperative strategies for improving nutrition and activity, along with early recognition and intervention in FTT may improve patient outcomes.

Localized Intra-Cavitary Therapy to Drive Systemic Anti-Tumor Immunity

Metastasis to the pleural and peritoneal cavities is a common terminal pathway for a wide variety of cancers. This article explores how these unique environments both promote aggressive tumor behavior and suppresses anti-tumor immunity, and ways in which local delivery of protein therapeutics can leverage the contained nature of these spaces to a therapeutic advantage, achieving high intra-cavital concentrations while minimizing systemic toxicity.

Encouraging long-term survival following autophagy inhibition using neoadjuvant hydroxychloroquine and gemcitabine for high-risk patients with resectable pancreatic carcinoma

INTRODUCTION

Preoperative autophagy inhibition with hydroxychloroquine (HCQ) in combination with gemcitabine in pancreatic adenocarcinoma (PDAC) has been shown to be safe and effective in inducing a serum biomarker response and increase resection rates in a previous phase I/II clinical trial. We aimed to analyze the long-term outcomes of preoperative HCQ with gemcitabine for this cohort.

METHODS

A review of patients enrolled between July 2010 and February 2013 in the completed phase I/II single arm (two doses of fixed-dose gemcitabine (1500 mg/m2 ) in combination with oral hydroxychloroquine administered for 31 consecutive days until the day of surgery for high-risk pancreatic cancer) was undertaken. Progression-free survival (PFS) and overall survival analysis (OS) using Kaplan-Meier estimates were performed.

RESULTS

Of 35 patients initially enrolled, 29 patients underwent surgical resection (median age at diagnosis: 62 years, 45% females). Median duration of follow-up was 7.5 years. There was a median 15% decrease in the serum CA19-9 levels following completion of neoadjuvant therapy and 83% of the cohort underwent a pancreaticoduodenectomy, 7 (24%) patients had a concomitant venous resection. On histopathology, 14 (48%) patients had at least a partial treatment response. The median PFS and OS were 11 months (95% Confidence interval [CI]: 7-28) and 31 months (95% CI: 13-47), respectively, while 9 (31%) patients survived beyond 5 years from diagnosis; a rate that compares very favorably with contemporaneous series.

CONCLUSION

Compared to historical data, neoadjuvant autophagy inhibition with HCQ plus gemcitabine is associated with encouraging long-term survival for patients with PDAC.

Oncolytic vaccinia virus delivering tethered IL-12 enhances antitumor effects with improved safety

Immune checkpoint blockade is arguably the most effective current cancer therapy approach; however, its efficacy is limited to patients with "hot" tumors, warranting an effective approach to transform "cold" tumors. Oncolytic viruses (especially properly armed ones) have positive effects on almost every aspect of the cancer-immunity cycle and can change the cancer-immune set point of a tumor. Here, we tested whether oncolytic vaccinia virus delivering tethered interleukin 12 (IL-12) could turn a "cold" tumor into a "hot" tumor while avoiding IL-12's systemic toxicity. Our data demonstrated that tethered IL-12 could be maintained in the tumor without treatment-induced toxic side effects. Moreover, the treatment facilitated tumor infiltration of more activated CD4⁺ and CD8⁺ T cells and less Tregs, granulocytic myeloid-derivedsuppressor cells, and exhausted CD8⁺ T cells, with increased interferon γ and decreased transforming growth factor β, cyclooxygenase-2, and vascular endothelial growth factor expression, leading to transformed, immunogenic tumors and improved survival. Combined with programmed cell death 1 blockade, vaccinia virus expressing tethered IL-12 cured all mice with late-stage colon cancer, suggesting immediate translatability to the clinic.

BAX-dependent mitochondrial pathway mediates the crosstalk between ferroptosis and apoptosis

Ferroptosis is considered a distinctive form of cell death compared to other types of death such as apoptosis. It is known to result from iron-dependent accumulation of lipid peroxides rather than caspase activation. However, we reported recently that ferroptosis interplays with apoptosis. In this study, we investigated a possible mechanism of this interplay between ferroptosis and apoptosis. Results from our studies reveal that combined treatment of the ferroptotic agent erastin and the apoptotic agent TRAIL effectively disrupted mitochondrial membrane potential (ΔΨm) and subsequently promoted caspase activation. The alterations of mitochondrial membrane potential are probably due to an increase in oligomerization of BAX and its accumulation at the mitochondria during treatment with erastin and TRAIL. Interestingly, the combined treatment-promoted apoptosis was effectively inhibited in BAX-deficient HCT116 cells, but not BAK-deficient cells. These results indicate that the BAX-associated mitochondria-dependent pathway plays a pivotal role in erastin-enhanced TRAIL-induced apoptosis.

Optimal management of patients with operable pancreatic head cancer: A Markov decision analysis

INTRODUCTION

Neoadjuvant therapy (NAT) is an emerging strategy for operable pancreatic ductal adenocarcinoma (PDAC). While NAT increases multimodal therapy completion, it risks functional decline and treatment dropout. We used decision analysis to determine optimal management of localized PDAC and consider risks faced by elderly patients.

METHODS

A Markov cohort decision analysis model evaluated treatment options for a 60-year-old patient with resectable PDAC: (1) upfront pancreaticoduodenectomy or (2) NAT. One-way and probabilistic sensitivity analyses were performed. A subanalysis considered the scenario of a 75-year-old patient.

RESULTS

For the base case, NAT offered an incremental survival gain of 4.6 months compared with SF (overall survival: 26.3 vs. 21.7 months). In one-way sensitivity analyses, findings were sensitive to recurrence-free survival for NAT patients undergoing adjuvant, probability of completing NAT, and probability of being resectable at exploration after NAT. On probabilistic analysis, NAT was favored in a majority of trials (97%) with a median survival benefit of 5.1 months. In altering the base case for the 75-year-old scenario, NAT had a survival benefit of 3.8 months.

CONCLUSIONS

This analysis demonstrates a significant benefit to NAT in patients with localized PDAC. This benefit persists even in the elderly cohort.

Definition and Prediction of Early Recurrence and Mortality Following Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy for Colorectal Peritoneal Metastases: Towards Predicting Oncologic Futility Preoperatively

INTRODUCTION

Early recurrence (ER) is a significant challenge for patients with colorectal peritoneal metastases (CRPM) following cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS HIPEC). Preoperative risk stratification for ER would improve preoperative decision making.

METHODS

We conducted a retrospective study examining patients who underwent CRS HIPEC for CRPM from 2000 to 2018. Optimal definition of ER was determined via minimum p-value approach based on differentiation of post-recurrence survival. Risk factors for ER were assessed in a derivation cohort by uni- and multivariate logistic regression. A predictive score for ER was generated using preoperative variables and validated in an independent cohort.

RESULTS

384 patients were analyzed, 316 (82%) had documented recurrence. Optimal length of post-operative RFS to distinguish ER (n = 144, 46%) vs. late recurrence (LR) (n = 172, 63%) was 8 mos (p<0.01). ER patients had shorter median OS post-CRS-HIPEC (13.6 vs. 39.4 mos, p<0.01). Preoperative BMI (OR 1.88), liver lesions (OR 1.89), progression on chemotherapy (OR 2.14), positive lymph nodes (OR 2.47) and PCI score (16-20: OR 1.7; >20: OR 4.37) were significant predictors of ER (all p<0.05). Using this model, patients were assigned risk scores from 0 to 9. Intermediate (scores 4-6) and high-risk patients (score 7-9) had observed rates of ER of 56% and 79% and overall 2-year survival rates of 27% and 0% respectively. The model showed fair discrimination (AUC 0.72) and good calibration (Hosmer-Lemeshow GOF p = 0.68).

CONCLUSIONS

ER predicts markedly worse OS following surgery. Preoperative factors can accurately stratify risk for ER and identify patients in whom CRS-HIPEC for CPRM is futile.

Impact of Neoadjuvant Therapy on Survival Following Margin-Positive Resection for Pancreatic Cancer

INTRODUCTION

A positive microscopic margin (R1) following resection of pancreatic ductal adenocarcinoma (PDAC) can occur in up to 80% of patients and is associated with reduced survival and increased recurrence. Our aim was to characterize the impact of neoadjuvant therapy (NAT) on survival and recurrence in patients with PDAC following an R1 resection.

METHODS

A retrospective analysis of patients with PDAC who underwent pancreatectomy from 2008 to 2017 was performed. Patients were staged according to the American Joint Committee on Cancer 8th edition and stratified based on resection margin (R0 vs. R1) and treatment sequence (NAT vs. surgery first [SF]). Conditional survival analysis was performed using Cox regression and inverse probability weighted estimates.

RESULTS

Among 580 patients, 59% received NAT and 41% underwent SF. On final pathology, the NAT cohort had smaller tumors and less lymph node (LN) positivity (p < 0.05). NAT was not associated with an R1 resection (50%, p = 0.653). Compared with the R1 cohort, the R0 cohort had a higher median overall survival (OS; 39.6 vs. 22.8 months; hazard ratio [HR] 1.6, p < 0.001) and disease-free survival (DFS; 19 vs. 13 months; HR 1.35, p = 0.004). After risk adjustment, NAT was not associated with OS, regardless of margin status (R0, 95% confidence interval [CI] (-)7.31-27.07, p = 0.26; or R1, 95% CI (-)36.99-15.25, p = 0.42). However, NAT was associated with improved DFS in the R1 cohort (95% CI 1.79-11.91, p = 0.008) but not in the R0 cohort (95% CI (-)11.22-10.54, p = 0.95).

CONCLUSION

An R0 resection remains an important determinant of overall and disease-free survival, even when NAT is administered. For patients with an R1 resection, receipt of NAT may prolong DFS.

Intratumoral expression of interleukin 23 variants using oncolytic vaccinia virus elicit potent antitumor effects on multiple tumor models via tumor microenvironment modulation

Background: Newly emerging cancer immunotherapy has led to significant progress in cancer treatment; however, its efficacy is limited in solid tumors since the majority of them are “cold” tumors. Oncolytic viruses, especially when properly armed, can directly target tumor cells and indirectly modulate the tumor microenvironment (TME), resulting in “hot” tumors. These viruses can be applied as a cancer immunotherapy approach either alone or in combination with other cancer immunotherapies. Cytokines are good candidates to arm oncolytic viruses. IL-23, an IL-12 cytokine family member, plays many roles in cancer immunity. Here, we used oncolytic vaccinia viruses to deliver IL-23 variants into the tumor bed and explored their activity in cancer treatment on multiple tumor models.

Methods: Oncolytic vaccinia viruses expressing IL-23 variants were generated by homologue recombination. The characteristics of these viruses were in vitro evaluated by RT-qPCR, ELISA, flow cytometry and cytotoxicity assay. The antitumor effects of these viruses were evaluated on multiple tumor models in vivo and the mechanisms were investigated by RT-qPCR and flow cytometry.

Results: IL-23 prolonged viral persistence, probably mediated by up-regulated IL-10. The sustainable IL-23 expression and viral oncolysis elevated the expression of Th1 chemokines and antitumor factors such as IFN-γ, TNF-α, Perforin, IL-2, Granzyme B and activated T cells in the TME, transforming the TME to be more conducive to antitumor immunity. This leads to a systemic antitumor effect which is dependent on CD8⁺ and CD4⁺ T cells and IFN-γ. Oncolytic vaccinia viruses could not deliver stable IL-23A to the tumor, attributed to the elevated tristetraprolin which can destabilize the IL-23A mRNA after the viral treatment; whereas vaccinia viruses could deliver membrane-bound IL-23 to elicit a potent antitumor effect which might avoid the possible toxicity normally associated with systemic cytokine exposure.

Conclusion: Either secreted or membrane-bound IL-23-armed vaccinia virus can induce potent antitumor effects and IL-23 is a candidate cytokine to arm oncolytic viruses for cancer immunotherapy.

500 Minimally Invasive Robotic Pancreatoduodenectomies: One Decade of Optimizing Performance

OBJECTIVES

This study aims to present the outcomes of our decade-long experience of robotic pancreatoduodenectomy and provide insights into successful program implementation.

BACKGROUND

Despite significant improvement in mortality over the past 30 years, morbidity following open pancreatoduodenectomy remains high. We implemented a minimally invasive pancreatic surgery program based on the robotic platform as one potential method of improving outcomes for this operation.

METHODS

A retrospective review of a prospectively maintained institutional database was performed to identify patients who underwent robotic pancreatoduodenectomy (RPD) between 2008 and 2017 at the University of Pittsburgh.

RESULTS

In total, 500 consecutive RPDs were included. Operative time, conversion to open, blood loss, and clinically relevant postoperative pancreatic fistula improved early in the experience and have remained low despite increasing complexity of case selection as reflected by increasing number of patients with pancreatic cancer, vascular resections, and higher Charlson Comorbidity scores (all P<0.05). Operating room time plateaued after 240 cases at a median time of 391 minutes (interquartile rang 340-477). Major complications (Clavien >2) occurred in less than 24%, clinically relevant postoperative pancreatic fistula in 7.8%, 30- and 90-day mortality were 1.4% and 3.1% respectively, and median length of stay was 8 days. Outcomes were not impacted by integration of trainees or expansion of selection criteria.

CONCLUSIONS

Structured implementation of robotic pancreatoduodenectomy can be associated with excellent outcomes. In the largest series of RPD, we establish benchmarks for the surgical community to consider when adopting this approach.

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.