Faculty Bibliography

INTRODUCTION/BACKGROUND:Robotic pancreaticoduodenectomy is slowly gaining acceptance within pancreatic surgery. Advantages have been demonstrated for robotic surgery in other fields, but robust data for pancreaticoduodenectomy is limited. The aim of this study was to compare the short-term outcomes of robotic pancreaticoduodenectomy (RPD) to open pancreaticoduodenectomy (OPD) and laparoscopic pancreaticoduodenectomy (LPD). METHODS:Patients who underwent a pancreaticoduodenectomy between January 2011 and July 2019 at the Johns Hopkins Hospital were included in this retrospective propensity-matched analysis. The RPD cohort was matched to patients who underwent OPD in a 1:2 fashion and LPD in a 1:1 fashion. Short-term outcomes were analyzed for all three cohorts. RESULTS:In total, 1644 patients were included, of which 96 (5.8%) underwent RPD, 131 (8.0%) LPD, and 1417 (86.2%) OPD. RPD was associated with a decreased incidence of delayed gastric emptying (9.4%) compared to OPD (23.5%; P = 0.006). The median estimated blood loss was significantly less in the RPD cohort (RPD vs OPD, 150 vs 487 mL; P < 0.001, RPD vs LPD, 125 vs 300 mL; P < 0.001). Compared to OPD, the robotic approach was associated with a shorter median length of stay (median 8 vs 9 days; P = 0.014) and a decrease in wound complications (4.2% vs 16.7%; P = 0.002). The incidence of other postoperative complications was comparable between RPD and OPD, and RPD and LPD. CONCLUSION/CONCLUSIONS:In the hands of experienced surgeons, RPD may have a modest yet statistically significant reduction in estimated blood loss, postoperative length of stay, wound complications, and delayed gastric emptying comparing to OPD in similar patients.

Hepatocellular carcinoma (HCC) is the sixth most common and the fourth most deadly cancer worldwide. The development cost of new therapeutics is a major limitation in patient outcomes. Importantly, there is a paucity of preclinical HCC models in which to test new small molecules. Herein, we implemented potentially novel patient-derived organoid (PDO) and patient-derived xenografts (PDX) strategies for high-throughput drug screening. Omacetaxine, an FDA-approved drug for chronic myelogenous leukemia (CML), was found to be a top effective small molecule in HCC PDOs. Next, omacetaxine was tested against a larger cohort of 40 human HCC PDOs. Serial dilution experiments demonstrated that omacetaxine is effective at low (nanomolar) concentrations. Mechanistic studies established that omacetaxine inhibits global protein synthesis, with a disproportionate effect on short-half-life proteins. High-throughput expression screening identified molecular targets for omacetaxine, including key oncogenes, such as PLK1. In conclusion, by using an innovative strategy, we report - for the first time to our knowledge - the effectiveness of omacetaxine in HCC. In addition, we elucidate key mechanisms of omacetaxine action. Finally, we provide a proof-of-principle basis for future studies applying drug screening PDOs sequenced with candidate validation in PDX models. Clinical trials could be considered to evaluate omacetaxine in patients with HCC.

OBJECTIVE:To examine the prognostic impact of tumor laterality in colon cancer liver metastases (CLM) after stratifying by Kirsten rat sarcoma 2 viral oncogene homolog (KRAS) mutational status. BACKGROUND:Although some studies have demonstrated that patients with CLM from a right sided (RS) primary cancer fare worse, others have found equivocal outcomes of patients with CLM with RS versus left-sided (LS) primary tumors. Importantly, recent evidence from unresectable metastatic CRC suggests that tumor laterality impacts prognosis only in those with wild-type tumors. METHODS:Patients with rectal or transverse colon tumors and those with unknown KRAS mutational status were excluded from analysis. The prognostic impact of RS versus LS primary CRC was determined after stratifying by KRAS mutational status. RESULTS:277 patients had a RS (38.6%) and 441 (61.4%) had a LS tumor. Approximately one-third of tumors (28.1%) harbored KRAS mutations. In the entire cohort, RS was associated with worse 5-year overall survival (OS) compared with LS (39.4% vs 50.8%, P = 0.03) and remained significantly associated with worse OS in the multivariable analysis (hazard ratio 1.45, P = 0.04). In wild-type patients, a worse 5-year OS associated with a RS tumor was evident in univariable analysis (43.7% vs 55.5%, P = 0.02) and persisted in multivariable analysis (hazard ratio 1.49, P = 0.01). In contrast, among patients with KRAS mutated tumors, tumor laterality had no impact on 5-year OS, even in the univariable analysis (32.8% vs 34.0%, P = 0.38). CONCLUSIONS:This study demonstrated, for the first time, that the prognostic impact of primary tumor side differs according to KRAS mutational status. RS tumors were associated with worse survival only in patients with wild-type tumors.

MINI: An international survey of high-volume pancreas cancer surgeons revealed wide variations in management preferences, attitudes regarding contraindications to surgery, and the propensity to offer exploration. When presented with 6 hypothetical clinical vignettes using details from real patients that have received R0 resection, only 14% to 53% of participating surgeons were willing to offer exploration following neoadjuvant therapy.

BACKGROUND:Modern chemotherapeutics have led to improved systemic disease control for patients with locally advanced pancreatic cancer (LAPC). Surgical strategies such as distal pancreatectomy with celiac axis resection (DP-CAR) are increasingly entertained. Herein we review procedure-specific outcomes and assess biologic rationale for DP-CAR. METHODS:A prospectively maintained single-institution database of all pancreatectomies was queried for patients undergoing DP-CAR. We excluded all patients for whom complete data were not available and those who were not treated with contemporary multi-agent therapy. Data were supplemented with dedicated chart review and outreach for long-term oncologic outcomes. RESULTS:Fifty-four patients underwent DP-CAR between 2008 and 2018. The median age was 62.7 years. Ninety-eight percent received induction chemotherapy. Arterial reconstruction was performed in 17% and concomitant visceral resection in 30%. The R0 resection rate was 87%. Postoperative complications were common (43%) with chyle leak being the most frequent (17%). Length of stay was 8 days, readmission occurred in one-third, and 90-day mortality was 2%. Disease recurrence occurred in 74% during a median follow up of 17.4 months. Median recurrence-free (RFS) and overall survival (OS) were 9 and 25 months, respectively. CONCLUSIONS:Following modern induction paradigms, DP-CAR can be performed with low mortality, manageable morbidity, and excellent rates of margin-negative resection in high-volume settings. The profile of complications of DP-CAR is distinct from pancreaticoduodenectomy and simple distal pancreatectomy. OS and RFS are similar to those undergoing resection of borderline resectable and resectable disease. Improved systemic disease control will likely lead to increasing utilization of aggressive surgical approaches to LAPC.

Most patients diagnosed with pancreatic cancer are classified as nonoperative candidates based on the contemporary guidelines of resectability. The advent of more potent control of systemic disease using neoadjuvant chemotherapy has enabled more aggressive operative interventions. In our multidisciplinary practice, patients with Stage III, locally advanced pancreatic cancer and superior mesenteric artery (SMA) encasement are now carefully triaged with high quality, preoperative imaging to determine if they can be considered candidates for operative resection with periadventitial dissection of the SMA. Patients displaying a "halo sign," where the encased SMA remains fully patent and free from arterial invasion, are now candidates for SMA periadventitial dissection. This procedure involves the surgical stripping of the infiltrated neurolymphatic tissue off the SMA leaving behind a bare "skeletonized artery." Alternatively, the "string sign" involving the SMA confers a more likely case of arterial invasion, where a complete oncologic resection cannot be achieved successfully. This method of patient selection in case of SMA involvement abandons the traditional metrics of circumferential degrees of the arterial encasement to guide surgical decisions. Our institutional approach has allowed us to meaningfully expand our operative methods of resection with the potential for improved longitudinal outcomes to pancreatic cancer patients who were deprived historically from the more effective and possibly curative treatment.

OBJECTIVE:The aim of this study was to critically analyze the surgical experience of managing autoimmune pancreatitis (AIP) in an era of modern diagnostics and compare these patients with those who were managed conservatively. METHODS:Two prospectively maintained databases were used to retrospectively identify patients with AIP who were either managed conservatively or underwent pancreatectomy. RESULTS:Eighty-eight patients were included in the study, of which 56 (63.6%) underwent resection and 32 (36.4%) were managed conservatively. Patients who underwent resection were more likely to present with jaundice (64.3% vs 18.1%, P < 0.001) and weight loss (53.6% vs 15.6%, P = 0.005). The cohort who underwent resection had a significantly higher median carbohydrate antigen 19-9 (40.0 vs 18.6 U/mL, P = 0.034) and was less likely to have elevated immunoglobulin G4 (26.1% vs 50.0%, P < 0.001). The most frequent initial diagnosis in the cohort who underwent resection was ductal adenocarcinoma (82.1%). Nine patients (28.1%) in the conservatively managed cohort experienced AIP relapse compared with 6 patients (10.7%) in the cohort who underwent resection. CONCLUSIONS:The most frequent reason for surgical resection of AIP is concern for malignancy. Carbohydrate antigen 19-9 elevations were more common than immunoglobulin G4 in our cohort, suggesting that this laboratory profile is suboptimal for this population.

BACKGROUND:Lymph node (LN) metastasis is associated with decreased survival following resection for pancreatic ductal adenocarcinoma (PDAC). In N0 disease, increasing total evaluated LN (ELN) correlates with improved outcomes suggesting patients may be understaged when LNs are undersampled. We aim to assess the optimal number of examined lymph nodes (ELN) following pancreatectomy. METHODS:Data from 1837 patients undergoing surgery were prospectively collected. The binomial probability law was utilized to analyze the minimum number of examined LNs (minELN) and accurately characterize each histopathologic stage. LN ratio (LNR) was compared to American Joint Committee on Cancer (AJCC) guidelines. RESULTS:As ELN total increased, the likelihood of finding node positive disease increased. An evaluation based upon the binomial probability law suggested an optimal minELN of 12 for accurate AJCC N staging. As the number of ELNs increased, the discriminatory capacity of alternative strategies to characterize LN disease exceeded that offered by AJCC N stage. CONCLUSION/CONCLUSIONS:This is the first study dedicated to optimizing histopathologic staging in PDAC using models of minELN informed by the binomial probability law. This study highlights two separate cutoffs for ELNs depending upon prognostic goal and validates that 12 LNs are adequate to determine AJCC N stage for the majority of patients.

BACKGROUND:Pancreatoduodenectomies at high risk for clinically relevant pancreatic fistula are uncommon, yet intimidating, situations. In such scenarios, the impact of individual surgeon experience on outcomes is poorly understood. METHODS:The fistula risk score was applied to identify high-risk patients (fistula risk score 7-10) from 7,706 pancreatoduodenectomies performed at 18 international institutions (2003-2020). For each case, surgeon pancreatoduodenectomy career volume and years of practice were linked to intraoperative fistula mitigation strategy adoption and outcomes. Consequently, best operative approaches for clinically relevant pancreatic fistula prevention and best performer profiles were identified through multivariable analysis models. RESULTS:Eight hundred and thirty high-risk pancreatoduodenectomies, performed by 64 surgeons, displayed an overall clinically relevant pancreatic fistula rate of 33.7%. Clinically relevant pancreatic fistula rates decreased with escalating surgeon career pancreatoduodenectomy (-49.7%) and career length (-41.2%; both P < .001), as did transfusion and reoperation rates, postoperative morbidity index, and duration of stay. Great experience (≥400 pancreatoduodenectomies performed or ≥21-year-long career) was a significant predictor of clinically relevant pancreatic fistula prevention (odds ratio 0.52, 95% confidence interval 0.35-0.76) and was more often associated with pancreatojejunostomy reconstruction and prophylactic octreotide omission, which were both independently associated with clinically relevant pancreatic fistula reduction. A risk-adjusted performance analysis also correlated with experience. Moreover, minimizing blood loss (≤400 mL) significantly contributed to clinically relevant pancreatic fistula prevention (odds ratio 0.40, 95% confidence interval 0.22-0.74). CONCLUSION/CONCLUSIONS:Surgeon experience is a key contributor to achieve better outcomes after high-risk pancreatoduodenectomy. Surgeons can improve their performance in these challenging situations by employing pancreatojejunostomy reconstruction, omitting prophylactic octreotide, and minimizing blood loss.

BACKGROUND:Historically, a positive margin after pancreatectomy for pancreatic ductal adenocarcinoma (PDAC) was associated with decreased survival. In an era when neoadjuvant chemotherapy (NAC) is being used frequently, the prognostic significance of margin status is unclear. STUDY DESIGN/METHODS:Patients with localized PDAC who received NAC and underwent pancreatectomy from 2011-2018 were identified from a single-institution database. Patients with fewer than 2 months of NAC, R2 resection, or less than 90-day follow-up were excluded. A positive margin included tumors within 1 mm of the surgical margin. RESULTS:468 patients met inclusion criteria. The median age was 65 and 53% were female. Preoperative clinical staging demonstrated most had locally advanced (n=222, 47%) or borderline resectable (n=172, 37%) disease. The median follow-up was 18.5 (10.6-30.0) months. The median duration of NAC was 119 (IQR:87-168) days. FOLFIRINOX was first-line therapy for 67%, and 73% received neoadjuvant radiotherapy. Most underwent pancreaticoduodenectomy (69%). 40% were node positive and 80% had an R0 resection. 56% received at least one cycle of adjuvant therapy. Median overall survival (OS) and recurrence-free survival (RFS) were 22.0 (CI: 19.4-25.1) and 11.0 (CI: 10.0-12.1) months. On multivariate analysis, margin status was not a significant predictor of OS or RFS. Factors associated with OS included: clinical stage, duration of NAC, nodal status, histopathologic treatment response score, and receipt of adjuvant chemotherapy. CONCLUSIONS:Microscopic margin positivity is not associated with recurrence and survival in localized PDAC patients resected after treatment with NAC. Aggressive surgical extirpation in high volume centers should be considered in selected patients after extensive NAC.