Transforming the Future of Surgeon-Scientists.

OBJECTIVE: To create a blueprint for surgical department leaders, academic institutions, and funding agencies to optimally support surgeon-scientists. BACKGROUND: Scientific contributions by surgeons have been transformative across many medical disciplines. Surgeon-scientists provide a distinct approach and mindset toward key scientific questions. However, lack of institutional support, pressure for increased clinical productivity, and growing administrative burden are major challenges for the surgeon-scientist, as is the time-consuming nature of surgical training and practice. METHODS: An American Surgical Association Research Sustainability Task Force was created to outline a blueprint for sustainable science in surgery. Leaders from top NIH-sponsored departments of surgery engaged in video and in-person meetings between January and April 2023. A strength, weakness, opportunities, threats analysis was performed, and workgroups focused on the roles of surgeons, the department and institutions, and funding agencies. RESULTS: Taskforce recommendations: (1) SURGEONS: Growth mindset : identifying research focus, long-term planning, patience/tenacity, team science, collaborations with disparate experts; Skill set : align skills and research, fill critical skill gaps, develop team leadership skills; DEPARTMENT OF SURGERY (DOS): (2) MENTORSHIP: Chair : mentor-mentee matching/regular meetings/accountability, review of junior faculty progress, mentorship training requirement, recognition of mentorship (eg, relative value unit equivalent, awards; Mentor: dedicated time, relevant scientific expertise, extramural funding, experience and/or trained as mentor, trusted advisor; Mentee : enthusiastic/eager, proactive, open to feedback, clear about goals; (3) FINANCIAL SUSTAINABILITY: diversification of research portfolio, identification of matching funding sources, departmental resource awards (eg, T-/P-grants), leveraging of institutional resources, negotiation of formalized/formulaic funds flow investment from academic medical center toward science, philanthropy; (4) STRUCTURAL/STRATEGIC SUPPORT: Structural: grants administrative support, biostats/bioinformatics support, clinical trial and research support, regulatory support, shared departmental laboratory space/equipment; Strategic: hiring diverse surgeon-scientist/scientists faculty across DOS, strategic faculty retention/ recruitment, philanthropy, career development support, progress tracking, grant writing support, DOS-wide research meetings, regular DOS strategic research planning; (5) COMMUNITY AND CULTURE: Community: right mix of faculty, connection surgeon with broad scientific community; Culture: building research infrastructure, financial support for research, projecting importance of research (awards, grand rounds, shoutouts); (6) THE ROLE OF INSTITUTIONS: Foundation: research space co-location, flexible start-up packages, courses/mock study section, awards, diverse institutional mentorship teams; Nurture: institutional infrastructure, funding (eg, endowed chairs), promotion friendly toward surgeon-scientists, surgeon-scientists in institutional leadership positions; Expectations: RVU target relief, salary gap funding, competitive starting salaries, longitudinal salary strategy; (7) THE ROLE OF FUNDING AGENCIES: change surgeon research training paradigm, offer alternate awards to K-awards, increasing salary cap to reflect market reality, time extension for surgeon early-stage investigator status, surgeon representation on study section, focused award strategies for professional societies/foundations. CONCLUSIONS: Authentic recommitment from surgeon leaders with intentional and ambitious actions from institutions, corporations, funders, and society is essential in order to reap the essential benefits of surgeon-scientists toward advancements of science.

Identifying the optimal treatment strategy in patients with resectable non-cardia gastric cancer.

BACKGROUND: Multimodal treatment strategy including perioperative chemotherapy (PEC), postoperative chemoradiation therapy (POCR), and postoperative chemotherapy (POC) has been accepted as the standard of care in gastric cancer (GC). The ideal sequence and type of therapy remain undetermined. METHOD: The National Cancer Database was examined from 2006 to 2016 to identify patients with resectable non-cardia gastric cancer. Patient outcomes were compared based on the receipt of PEC, POCR, and POC. This comparison was repeated in a sub-group of patients who received optimal treatment. Optimal treatment was defined as initial chemotherapy within 45 days of diagnosis, resection within 45 days of diagnosis, negative margins, adjuvant chemotherapy within 90 days of resection and standard radiation dose (45 Gy). Kaplan-Meier test, log-rank test, and multivariable analysis (MVA) were performed. RESULTS: We identified 9589 patients. Median survival was greater in the PEC group followed by POCR and POC (60.6, 42.3, and 31.2 months, respectively). On MVA, factors associated with worse overall survival included age above median (≥ 63 years), Charlson-Deyo score of ≥ 1, non-academic/research program, poorly differentiated/undifferentiated grade, positive margins, and positive lymph nodes. Both PEC and POCR were associated with improved survival when compared to POC (HR 0.78 and 0.79; p < 0.001). When compared with PEC, no significant difference was noted with POCR (HR 1.01; p = 0.987). These results were maintained in optimally treated cohort (n = 3418). CONCLUSION: In patients with resectable non-cardia gastric cancer, both perioperative chemotherapy and postoperative chemoradiation therapy were associated with improved survival when compared to postoperative chemotherapy. No difference was noted between perioperative chemotherapy and postoperative chemoradiation therapy. These results were maintained in the optimally treated cohort.

Netrin-1 feedforward mechanism promotes pancreatic cancer liver metastasis via hepatic stellate cell activation, retinoid, and ELF3 signaling.

The biology of metastatic pancreatic ductal adenocarcinoma (PDAC) is distinct from that of the primary tumor due to changes in cell plasticity governed by a distinct transcriptome. Therapeutic strategies that target this distinct biology are needed. We detect an upregulation of the neuronal axon guidance molecule Netrin-1 in PDAC liver metastases that signals through its dependence receptor (DR), uncoordinated-5b (Unc5b), to facilitate metastasis in vitro and in vivo. The mechanism of Netrin-1 induction involves a feedforward loop whereby Netrin-1 on the surface of PDAC-secreted extracellular vesicles prepares the metastatic niche by inducing hepatic stellate cell activation and retinoic acid secretion that in turn upregulates Netrin-1 in disseminated tumor cells via RAR/RXR and Elf3 signaling. While this mechanism promotes PDAC liver metastasis, it also identifies a therapeutic vulnerability, as it can be targeted using anti-Netrin-1 therapy to inhibit metastasis using the Unc5b DR cell death mechanism.

Does non-metastatic gastric cancer of the cardia warrant a different treatment strategy?

BACKGROUND: Multimodal treatment strategies with surgery as its centerpiece have been accepted as the standard of care in nonmetastatic cardia gastric cancer (CGC). There remains a lack of consensus regarding the optimal multimodal treatment strategy. METHOD: We queried National Cancer Database from 2004 to 2016 to identify patients with resected nonmetastatic CGC who received perioperative chemotherapy (PEC), postoperative chemoradiation therapy (POCR), or postoperative chemotherapy (POC). A subgroup analysis was performed in optimally treated patients defined as initial chemotherapy within 45 days of diagnosis, resection within 45 days of diagnosis, negative margins, adjuvant chemotherapy within 90 days of resection, and standard radiation dose (45 Gy). Kaplan-Meier, Univariate analysis (UVA), and Multivariable analysis (MVA) were performed. RESULTS: We identified 2387 patients. Median survival was 38.8 months in the PEC group, 36 months in the POCR group, and 32.3 months in the POC group (p = 0.1025). On UVA, patients treated with PEC had an association with improved survival (HR, 0.83; p = 0.037) when compared with POC. On MVA, no significant difference was noted in overall survival (OS) between PEC, POCR, and POC, similar to subgroup analysis of optimally treated cohort. CONCLUSION: OS rate in nonmetastatic CGC is not significantly different between patients receiving PEC, POCR, or POC.

Tumor microbiome links cellular programs and immunity in pancreatic cancer.

Microorganisms are detected in multiple cancer types, including in putatively sterile organs, but the contexts in which they influence oncogenesis or anti-tumor responses in humans remain unclear. We recently developed single-cell analysis of host-microbiome interactions (SAHMI), a computational pipeline to recover and denoise microbial signals from single-cell sequencing of host tissues. Here we use SAHMI to interrogate tumor-microbiome interactions in two human pancreatic cancer cohorts. We identify somatic-cell-associated bacteria in a subset of tumors and their near absence in nonmalignant tissues. These bacteria predominantly pair with tumor cells, and their presence is associated with cell-type-specific gene expression and pathway activities, including cell motility and immune signaling. Modeling results indicate that tumor-infiltrating lymphocytes closely resemble T cells from infected tissue. Finally, using multiple independent datasets, a signature of cell-associated bacteria predicts clinical prognosis. Tumor-microbiome crosstalk may modulate tumorigenesis in pancreatic cancer with implications for clinical management.

The Impact of Carbohydrate Antigen 19-9 on Survival in Patients with Clinical Stage I and II Pancreatic Cancer.

BACKGROUND: Carbohydrate antigen (CA) 19-9 is a biomarker to monitor treatment effect. A threshold to predict prognostic significance remains undefined. We evaluated the impact of CA19-9 on overall survival (OS) in patients with early-stage pancreatic cancer (PC) utilizing the National Cancer Database (NCDB). METHODS: The NCDB was queried from 2010 to 2014 to identify patients with clinical stage I-II PC. Patients who had undocumented pretreatment CA19-9 were excluded. Patients were stratified into two cohorts: CA19-9 < 98 U/mL and CA19-9 ≥ 98 U/mL, and further categorized into surgery versus no surgery. Twelve- and 24-month OS rates are reported. RESULTS: Overall, 32,382 patients (stage I: 12,173; stage II: 20,209) were included. The majority of stage I (52.1%) and II (60%) patients had CA19-9 ≥ 98 U/mL. Stage I-II patients with CA19-9 < 98 U/mL had improved OS rates (stage I: 67.5%, 42.6%; stage II: 59.8%, 32.8%) compared with stage I and II patients with CA19-9 ≥ 98 U/mL (stage I: 50.7%, 26.9%; stage II: 48.1%, 22%). Among resected stage I patients, CA19-9 <98 U/mL was associated with improved OS (< 98: 80.5%, 56%; ≥ 98: 70.2%, 42.8%), and a similar trend was seen in resected stage II patients (< 98: 77.6%, 49.9%; ≥ 98: 71%, 39.2%). Unresected stage I patients with lower CA19-9 had improved OS (< 98: 42.1%, 17.5; ≥ 98: 29.9%, 10%), with similar findings in unresected stage II patients (< 98: 41.1%, 15.3%; ≥ 98: 33.4%, 10.6%). CONCLUSIONS: Our study demonstrated the prognostic value of CA19-9 in patients with clinical stage I-II PC, with a value < 98 U/mL demonstrating improved survival. Surgery significantly improved survival at 12 and 24 months irrespective of CA19-9.

A review of hepatic epithelioid hemangioendothelioma-Analyzing patient characteristics and treatment strategies.

BACKGROUND: Hepatic epithelioid hemangioendothelioma (HEH) is a rare vascular tumor of unknown etiology and unpredictable natural history. To date, no large-scale studies have been published evaluating this disease due to its rare occurrence. METHODS: The National Cancer Database was reviewed between 2004 and 2016 to identify patients with HEH. Univariate analysis with overall survival (OS) was performed by Cox proportional hazards model. Kaplan-Meier method was used to create OS curves and compared using the log-rank test. RESULTS: We identified 229 patients with HEH. The majority of patients were female (61.1%), white (84.3%), and had a Charlson-Deyo score of 0 (75%). Chemotherapeutic intervention was seen in 26% of the patients while 33% received surgical intervention in the form of wedge/segmental liver resection (n = 27), hepatectomy lobectomy/extended lobectomy (n = 18), and liver transplant (n = 22). Five-year survival in surgical patients was 90.5%, 66.5% and 81%, respectively (p = 0.485). Age greater than 55 years (hazard ratio [HR], 2.78; p < 0.001), Asian ethnicity compared to white (HR, 2.84; p = 0.012), and a higher Charlson-Deyo score (score 1: HR, 2.28; p < 0.001 and score ≥2: HR, 2.76; p = 0.011) were associated with worse OS. CONCLUSION: Treatment for HEH remains variable with only a third of the patients undergoing surgery. International collaboration is necessary to determine the optimal treatment for this rare disease.

Surgery in combination with systemic chemotherapy is associated with improved survival in stage IV gallbladder cancer.

BACKGROUND: Gallbladder cancer (GBC) is the most common biliary malignancy frequently metastatic at diagnosis with poor prognosis. While surgery remains the standard for early-stage GBC, the role of surgery in patients with metastatic gastrointestinal cancers is expanding due to improvements in systemic therapies. We sought to evaluate the survival of patients with stage IV GBC undergoing surgery in an era of improved multi-agent systemic therapy. METHODS: A retrospective review of the National Cancer Database was performed. Patients with stage IV GBC who underwent systemic therapy were included. Patients who received radiation therapy, palliative therapy or had missing survival data were excluded. Univariable and multivariable analysis was performed. RESULTS: 4,145 patients were identified between 2004 and 2016. Mean age was 69. Surgery combined with systemic therapy predicted improved median survival compared with chemotherapy alone (11.1mo versus 6.8mo, HR 0.65, p < 0.001). Additionally, receipt of treatment after 2011 predicted improved survival (HR 0.86, p < 0.001). Patients treated with multi-agent chemotherapy in combination with surgery were associated with the greatest hazard ratio benefit (0.40, p < 0.001) versus single agent therapy alone. CONCLUSION: Patients with stage IV gallbladder cancer treated with a combination of surgery and chemotherapy are associated with an improved overall survival compared to chemotherapy alone. Patients receiving care during the more recent era demonstrated improved survival. These results support a role for surgery in selected patients with stage IV gallbladder cancer receiving chemotherapy.

Surgery is Associated With Improved Overall Survival in Patients With Metastatic Gastric Cancer: A National Cancer Database Analysis.

BACKGROUND: The 5-year overall survival (OS) rate for patients with metastatic gastric cancer (mGC) is 5.3%. Surgery for mGC is controversial. METHODS: We identified all mGC patients who received chemotherapy using the National Cancer Database (2004-2015). Patients were grouped according to surgery of: (1) the primary site (PS) only, (2) primary and distant sites (PDS), (3) distant site only (DS), or (4) no surgery (NS). A propensity score adjustment and multivariate regression was used to compare OS. RESULTS: Overall, 18,772 patients met the inclusion criteria: (1) PS (n = 962, 5.1%), (2) PDS (n = 380, 2.1%), (3) DS (n = 984, 5.2%), and 16,446 NS (87.6%). Surgery was associated with improved OS in the PS and PDS groups (hazard ratios: .489 (95% CI: .376-.636); .583 (95% CI: .420-.811), P < .001) (median OS 15.8 and 15.9 months vs 8.6 for NS patients, respectively). CONCLUSIONS: Gastrectomy with or without metastasectomy is associated with improved survival in stage IV gastric cancer patients receiving chemotherapy. This warrants further prospective studies.

p53 and Zinc: A Malleable Relationship.

A large percentage of transcription factors require zinc to bind DNA. In this review, we discuss what makes p53 unique among zinc-dependent transcription factors. The conformation of p53 is unusually malleable: p53 binds zinc extremely tightly when folded, but is intrinsically unstable in the absence of zinc at 37°C. Whether the wild-type protein folds in the cell is largely determined by the concentration of available zinc. Consequently, zinc dysregulation in the cell as well as a large percentage of tumorigenic p53 mutations can cause p53 to lose zinc, misfold, and forfeit its tumor suppressing activity. We highlight p53's noteworthy biophysical properties that give rise to its malleability and how proper zinc binding can be restored by synthetic metallochaperones to reactivate mutant p53. The activity and mechanism of metallochaperones are compared to those of other mutant p53-targeted drugs with an emphasis on those that have reached the clinical trial stage.

Early postoperative ERAS compliance predicts decreased length of stay and complications following liver resection.

BACKGROUND: Enhanced recovery after surgery (ERAS) components for liver resection lack standardization and compliance. We evaluated our ERAS protocol and describe the association of postoperative ERAS compliance with length of stay (LOS) and complications. METHODS: We retrospectively reviewed patients undergoing liver resection at our institution from 2016 to 2020. Pre- and post-ERAS outcomes and compliance at 72 h were compared with LOS and complications. LOS beyond 72 h was defined as LOS72. RESULTS: 210 patients were included. Post-ERAS patients had significantly shorter LOS (5.1 vs. 7.3 days, p = 0.0014) with no difference in 30-day mortality, morbidity, or readmissions. ERAS components associated with shorter LOS72 were regular diet (HR 1.73), fluid discontinuation (HR 1.63), drain removal (HR 1.94), multimodal and oral analgesia (HR 1.51), and ambulation >100 ft (HR 2.23). LOS72 was 1-day for ≥9 ERAS component compliance, 4-days for 6-8 components, and 6-days for <6 components. 30-day complication rates for patients with ≥9 components by postoperative day 3 (POD3) were significantly lower than those with 6-8 (12 vs 32%). CONCLUSION: ERAS decreases LOS after liver resection. Nutritional advancement, drain discontinuation, multimodal and oral analgesia, and ambulation >100 ft by POD3 are associated with decreased LOS72. Achieving ≥6 components by POD3 predicts decreased LOS72 and complications.

Defining the role of systemic therapy in resectable pancreatic acinar cell carcinoma.

INTRODUCTION: Following resection of pancreatic acinar cell carcinoma (PACC) distant recurrence remains high. We utilized the national cancer database (NCDB) to evaluate the role of systemic therapy in early-stage resected PACC. METHODS: We queried the NCDB registry from 2004 to 2015 for patients with pathologic stage I-IIB PACC. For each stage, patients who underwent surgery alone (SA) were compared to patients who received systemic and/or radiation therapy in addition to surgery (surgery + therapy [S + T]). RESULTS: A total of 271 patients (101 pI, 81 pIIA, and 89 pIIB) were analyzed. Of all clinically node positive patients (n = 41), the majority (n = 32, 78%) had node-positive disease at resection (pIIB). SA was performed in 112 patients (41.3%), whereas 159 (58.7%) patients received S + T. There was no difference in overall survival (OS) between S + T and SA with respect to pI or pIIA disease. In pIIB disease, S + T was associated with improved OS compared to SA (34.9 vs. 16.9 months, p = 0.031). Single-agent chemotherapy was associated with improved OS for pIIB disease when compared to SA (hazard ratio: 0.38, 95% confidence interval: 0.16, 0.83). CONCLUSION: In resectable PACC, the survival benefit of adjuvant therapy is limited to pathologic stage IIB disease. This benefit is evident even in patients treated with single-agent chemotherapy.

Urea Denaturation, Zinc Binding, and DNA Binding Assays of Mutant p53 DNA-binding Domains and Full-length Proteins.

In the cell, the thermodynamic stability of a protein - and hence its biological activity - can change dramatically as a result of perturbations in its amino acid sequence and the concentration of stabilizing ligands. This interplay is particularly evident in zinc-binding transcription factors such as the p53 tumor suppressor, whose DNA-binding activity can critically depend on levels of intracellular zinc as well as point mutations that alter either metal binding or folding stability. Separate protocols exist for determining a protein's metal affinity and its folding free energy. These properties, however, are intimately connected, and a technique is needed to integrate these measurements. Our protocols employ common non-fluorescent and fluorescent zinc chelators to control and report on free Zn2+ concentration, respectively, combined with biophysical assays of full-length human p53 and its DNA-binding domain. Fitting the data to equations that contain stability and metal-binding terms results in a more complete picture of how metal-dependent proteins can lose and gain DNA-binding function in a range of physiological conditions. Graphic abstract: Figure 1.Raising intracellular zinc can restore tumor-suppressing function to p53 that has been unfolded by missense mutation or cellular conditions.

Genetic Drivers of Ileal Neuroendocrine Tumors.

The genetic causes of ileal neuroendocrine tumors (ileal NETs, or I-NETs) have been a mystery. For most types of tumors, key genes were revealed by large scale genomic sequencing that demonstrated recurrent mutations of specific oncogenes or tumor suppressors. In contrast, genomic sequencing of ileal NETs demonstrated a distinct lack of recurrently mutated genes, suggesting that the mechanisms that drive the formation of I-NETs may be quite different than the cell-intrinsic mutations that drive the formation of other tumor types. However, recent mouse studies have identified the IGF2 and RB1 pathways in the formation of ileal NETs, which is supported by the subsequent analysis of patient samples. Thus, ileal NETs no longer appear to be a cancer without genetic causes.

Delayed cytokine release syndrome after neoadjuvant nivolumab: a case report and literature review.

Aim: Cytokine release syndrome (CRS) is an infrequently described immune-related adverse event of checkpoint inhibitors (CPI). CPI-induced CRS typically presents with fevers, hemodynamic instability and organ dysfunction within 2 weeks of the last treatment cycle. Case study: We report an unusual case of delayed and severe CRS occurring postoperatively in a patient with hepatic-limited metastatic colorectal cancer who received neoadjuvant immunotherapy. After a negative workup for alternative causes, he received prolonged corticosteroid treatment with symptom resolution. Conclusion: CPI-induced CRS can mimic sepsis and clinicians should maintain a high-index of suspicion to diagnose this immune-related adverse event early and initiate appropriate treatment. As use of perioperative immunotherapy increases, the potential role of surgery to trigger CRS in this case warrants further investigation.

Lay abstract Aim: Cytokine release syndrome (CRS) is a rare but potentially serious side effect of a class of immunotherapy drugs called checkpoint inhibitors (CPI). CRS typically presents with fevers and low blood pressure and can cause damage to organs including the kidneys and liver. Case study: We report an unusual case of severe CRS occurring after surgery in a patient who had received prior CPI therapy. After a thorough evaluation for alternative causes, he was diagnosed with CRS and treated successfully with steroids. Conclusion: It is important for medical providers to consider this potential side effect when treating patients with CPI. Further research is needed to clarify the role of surgery in CPI-induced CRS.

Benzothiazolyl and Benzoxazolyl Hydrazones Function as Zinc Metallochaperones to Reactivate Mutant p53.

We identified a set of thiosemicarbazone (TSC) metal ion chelators that reactivate specific zinc-deficient p53 mutants using a mechanism called zinc metallochaperones (ZMCs) that restore zinc binding by shuttling zinc into cells. We defined biophysical and cellular assays necessary for structure-activity relationship studies using this mechanism. We investigated an alternative class of zinc scaffolds that differ from TSCs by substitution of the thiocarbamoyl moiety with benzothiazolyl, benzoxazolyl, and benzimidazolyl hydrazones. Members of this series bound zinc with similar affinity and functioned to reactivate mutant p53 comparable to the TSCs. Acute toxicity and efficacy assays in rodents demonstrated C1 to be significantly less toxic than the TSCs while demonstrating equivalent growth inhibition. We identified C85 as a ZMC with diminished copper binding that functions as a chemotherapy and radiation sensitizer. We conclude that the benzothiazolyl, benzoxazolyl, and benzimidazolyl hydrazones can function as ZMCs to reactivate mutant p53 in vitro and in vivo.

Neoadjuvant therapy is associated with lower margin positivity rates after Pancreaticoduodenectomy in T1 and T2 pancreatic head cancers: An analysis of the National Cancer Database.

BACKGROUND: Neoadjuvant therapy (NAT) for T1/T2 pancreatic adenocarcinoma (PDAC) prior to pancreaticoduodenectomy remains controversial. We compared positive margin rates in patients with clinical T1&T2 tumors who did and did not receive NAT. METHODS: The National Cancer Database (NCDB) found clinical T1&T2 PDAC patients who underwent pancreaticoduodenectomy from 2004 to 2014. Univariate and multivariate regression determined factors associated with a positive margin and survival. RESULTS: 9795 patients underwent surgery for clinical T1 or T2 pancreatic head adenocarcinoma. 8472 patients had data regarding use of neoadjuvant and adjuvant therapies; of which, 774 (9.1%) received NAT and 435 (5.1%) received both chemotherapy and radiation therapy. NAT was found to lower positive margin rates from 21.8 to 15.5% (p < 0.0001) and when radiation was added this rate dropped to 13.4%. Positive margins were associated with worse overall survival (14.9 vs. 23.9 months; HR 1.702, p < 0.0001). CONCLUSIONS: NAT is associated with a reduced positive margin rate in patients with T1 and T2 tumors. These findings support ongoing and future clinical trials of NAT in T1 and T2, early stage PDAC to determine impacts on survival.