Phase 2 study of preoperative chemotherapy with nab-paclitaxel and gemcitabine followed by chemoradiation for borderline resectable or node-positive pancreatic ductal adenocarcinoma

BACKGROUND

Neoadjuvant treatment with nab-paclitaxel and gemcitabine for potentially operable pancreatic adenocarcinoma has not been well studied in a prospective interventional trial and could down-stage tumors to achieve negative surgical margins.

METHODS

A single-arm, open-label phase 2 trial (NCT02427841) enrolled patients with pancreatic adenocarcinoma deemed to be borderline resectable or clinically node-positive from March 17, 2016 to October 5, 2019. Patients received preoperative gemcitabine 1000 mg/m² and nab-paclitaxel 125 mg/m² on Days 1, 8, 15, every 28 days for two cycles followed by chemoradiation with 50.4 Gy intensity-modulated radiation over 28 fractions with concurrent fluoropyrimidine chemotherapy. After definitive resection, patients received four additional cycles of gemcitabine and nab-paclitaxel. The primary endpoint was R0 resection rate. Other endpoints included treatment completion rate, resection rate, radiographic response rate, survival, and adverse events.

RESULTS

Nineteen patients were enrolled, with the majority having head of pancreas primary tumors, both arterial and venous vasculature involvement, and clinically positive nodes on imaging. Among them, 11 (58%) underwent definitive resection and eight of 19 (42%) achieved R0 resection. Disease progression and functional decline were primary reasons for deferring surgical resection after neoadjuvant treatment. Pathologic near-complete response was observed in two of 11 (18%) resection specimens. Among the 19 patients, the 12-month progression-free survival was 58%, and 12-month overall survival was 79%. Common adverse events were alopecia, nausea, vomiting, fatigue, myalgia, peripheral neuropathy, rash, and neutropenia.

CONCLUSION

Gemcitabine and nab-paclitaxel followed by long-course chemoradiation represents a feasible neoadjuvant treatment strategy for borderline resectable or node-positive pancreatic cancer.

Socioeconomic and Geographic Disparities in the Referral and Treatment of Pancreatic Cancer at High-Volume Centers

Importance

Treatment at high-volume centers (HVCs) has been associated with improved overall survival (OS) in patients with pancreatic ductal adenocarcinoma (PDAC); however, it is unclear how patterns of referral affect these findings.

Objective

To understand the relative contributions of treatment site and selection bias in driving differences in outcomes in patients with PDAC and to characterize socioeconomic factors associated with referral to HVCs.

Design, Setting, Participants

A population-based retrospective review of the Oregon State Cancer Registry was performed from 1997 to 2019 with a median 4.3 months of follow-up. Study participants were all patients diagnosed with PDAC in Oregon from 1997 to 2018 (n = 8026).

Exposures

The primary exposures studied were diagnosis and treatment at HVCs (20 or more pancreatectomies for PDAC per year), low-volume centers ([LVCs] less than 20 per year), or both.

Main Outcomes and Measures

OS and treatment patterns (eg, receipt of chemotherapy and primary site surgery) were evaluated with Kaplan-Meier analysis and logistic regression, respectively.

Results

Eight thousand twenty-six patients (male, 4142 [52%]; mean age, 71 years) were identified (n = 3419 locoregional, n = 4607 metastatic). Patients receiving first-course treatment at a combination of HVCs and LVCs demonstrated improved median OS for locoregional and metastatic disease (16.6 [95% CI, 15.3-17.9] and 6.1 [95% CI, 4.9-7.3] months, respectively) vs patients receiving HVC only (11.5 [95% CI, 10.7-12.3] and 3.9 [95% CI, 3.5-4.3] months, respectively) or LVC-only treatment (8.2 [95% CI, 7.7-8.7] and 2.1 [95% CI, 1.9-2.3] months, respectively; all P < .001). No differences existed in disease burden by volume status of diagnosing institution. When stratifying by site of diagnosis, HVC-associated improvements in median OS were smaller (locoregional: 10.4 [95% CI, 9.5-11.2] vs 9.9 [95% CI, 9.4-10.4] months; P = .03; metastatic: 3.6 vs 2.7 months, P < .001) than when stratifying by the volume status of treating centers, indicating selection bias during referral. A total of 94% (n = 1103) of patients diagnosed at an HVC received HVC treatment vs 18% (n = 985) of LVC diagnoses. Among patients diagnosed at LVCs, later year of diagnosis and higher estimated income were independently associated with higher odds of subsequent HVC treatment, while older age, metastatic disease, and farther distance from HVC were independently associated with lower odds.

Conclusions and Relevance

LVC-to-HVC referrals for PDAC experienced improved OS vs HVC- or LVC-only care. While disease-related features prompting referral may partially account for this finding, socioeconomic and geographic disparities in referral worsen OS for disadvantaged patients. Measures to improve access to HVCs are encouraged.

Updates to NeoOPTIMIZE: An open-label, phase II trial and biomarker discovery platform to assess the efficacy of adaptive switching of modified FOLFIRINOX (mFFX) or gemcitabine/nab-paclitaxel (GA) as a neoadjuvant strategy for patients with resectable/borderline resectable and locally advanced unresectable pancreatic ductal adenocarcinoma (PDAC)

TPS776

Background: Neoadjuvant chemotherapy (NAC) and/or chemo-RT may confer benefit to patients with localized PDAC, by better tolerability, tumor down-staging, and increased R0 resections. mFFX or GA are the current NAC backbones; however, a lack of robust predictive biomarker(s) hampers identification of patients most likely to benefit from mFFX or GA. Further, desmoplastic stroma/poor vascularity compromise NAC efficacy, but angiotensin II receptor inhibitor, losartan, might remodel vascular perfusion to enhance chemotherapy activity. We designed the NeoOPTIMIZE trial for patients with newly diagnosed localized PDAC to provide a flexible clinical platform to: 1) evaluate the feasibility and efficacy of early switching of mFFX to GA, and 2) establish a robust biomarker/imaging discovery platform to optimize the NAC backbone. Methods: NeoOPTIMIZE (NCT04539808) is an open-label, non-randomized, phase II trial assessing the preliminary efficacy of an adaptive treatment strategy that allows for early switching of NAC in patients with localized PDAC. Sixty patients (n = 40 resectable/BRCP; n = 20 locally advanced unresectable [uLAPC]) will be enrolled to receive 2 months of preoperative mFFX (oxaliplatin, 85 mg/m2; folinic acid, 400 mg/m2; irinotecan, 150 mg/m2; 5-FU, 2400 mg/m2), then restaging by a multidisciplinary tumor board (multiD-TB). Absent progression (by panc protocol CT and CA19-9 decline/increase < 30% from baseline), patients continue mFFX (4 cycles). If progression (by panc protocol CT; CA19-9 increase > 30%), patients switch to GA (nab-paclitaxel, 125 mg/m2; gemcitabine, 1000 mg/m2) for 2 months. After 4 months of mFFX or mFFX/GA, another restaging multiD-TB will decide to proceed with: a) RT (if vascular involvement) then resection, b) resection, or c) continued chemo (if unresectable). Losartan (50 mg PO QD) is given throughout NAC and RT regimens. The primary endpoint estimates the proportion of resectable/BRPC patients with R0 resection. Assuming that the proportion of R0 is 60%, a sample size of 32 will provide a 95% CI (0.41, 076). To account for a 20% dropout, 40 patients will be enrolled towards primary endpoint. A separate exploratory cohort of 20 uLAPC patients will be enrolled. Secondary endpoints include DFS, PFS, OS, and AEs. Exploratory objectives include correlating clinical outcomes data with changes in blood-based biomarkers (CA19-9, ctDNA, circulating tumor cells etc.) and research DCE-MRI. To date, the trial has enrolled 19 patients: 8 resectable, 7 BRCP, and 4 uLAPC. Clinical trial information: NCT04539808 .

Complications in Distal Pancreatectomy versus Radical Antegrade Modular Pancreatosplenectomy: A Disease Risk Score Analysis Utilizing National Surgical Quality Improvement Project Data

INTRODUCTION

Radical antegrade modular pancreatosplenectomy (RAMPS) was developed to improve R0 resections and lymph node harvests versus distal pancreatectomy (DP) in pancreatic adenocarcinoma (PDAC); relative complication rates are understudied.

METHODS

Patients undergoing distal pancreas resections from 2006 to 2020 were identified from our institutional NSQIP database, grouped by resection method, and evaluated for the following outcomes: postoperative pancreatic fistula (POPF), clinically relevant POPF (crPOPF), incisional surgical site infection (iSSI), organ space SSI (osSSI), and Clavien-Dindo grade ≥ 3 (CD ≥ 3) complications using logistic regression. Patients were matched 1:1 based on disease risk score.

RESULTS

Two-hundred-thirty-six and 117 patients underwent DP and RAMPS, respectively. POPF, crPOPF, CD ≥ 3 complications, iSSI, and osSSIs occurred in 105 (30%), 43 (12%), 74 (21%), 34 (10%) and 52 (15%) patients, respectively. Disease risk score matching yielded 89 similar patients per group. On multivariable analysis, patients undergoing RAMPS were not significantly more likely to experience POPF (OR 0.69, P = 0.26), crPOPF (OR 0.41, P = 0.72), CD ≥ 3 complication (OR 0.78, P = 0.44), iSSI (OR 0.58, P = 0.27), or osSSI (OR 0.93, P = 0.86). Of patients with PDAC (n = 108) mean nodal harvest were 14.8 (SD 11.30) and 19.4 (SD 7.19) nodes for patients undergoing DP and RAMPS, respectively (P = 0.01). Six patients (20%) undergoing DP had positive margins versus 12 (15%) undergoing RAMPS (P = 0.56). At a median follow-up of 17 months, there was no difference in locoregional recurrence-free survival (P = 0.32) or overall survival (P = 0.92) on Kaplan-Meier analysis.

CONCLUSION

RAMPS does not result in increased complications compared to DP and routine use is encouraged in pancreatic malignancies.

Similar Outcomes in Minimally Invasive versus Open Management of Primary Pancreatic Neuroendocrine Tumors: A Regional, Multi-Institutional Collaborative Analysis

In pancreatic neuroendocrine tumors (PNETs), the impact of minimally invasive (MI) versus open resection on outcomes remains poorly studied. We queried a multi-institutional pancreatic cancer registry for patients with resected non-metastatic PNET from 1996−2020. Recurrence-free (RFS), disease-specific survival (DSS), and operative complications were evaluated. Two hundred and eighty-two patients were identified. Operations were open in 139 (49%) and MI in 143 (51%). Pancreaticoduodenectomy was performed in 77 (27%, n = 23 MI), distal pancreatectomy in 184 (65%, n = 109 MI), enucleation in 13 (5%), and total pancreatectomy in eight (3%). Median follow-up was 50 months. Thirty-six recurrences and 13 deaths from recurrent disease yielded 5-year RFS and DSS of 85% and 95%, respectively. On multivariable analysis, grade 1 (HR 0.07, p < 0.001) and grade 2 (HR 0.20, p = 0.002) tumors were associated with improved RFS, while T3/T4 tumors were associated with worse RFS (OR 2.78, p = 0.04). MI resection was not associated with RFS (HR 0.53, p = 0.14). There was insufficient mortality to evaluate DSS with multivariable analysis. Of 159 patients with available NSQIP data, incisional surgical site infections (SSIs), organ space SSIs, Grade B/C pancreatic fistulas, reoperations, and need for percutaneous drainage did not differ by operative approach (all p > 0.2). Nodal harvest was similar for MI versus open distal pancreatectomies (p = 0.16) and pancreaticoduodenectomies (p = 0.28). Minimally invasive surgical management of PNETs is equivalent for oncologic and postoperative outcomes.

NeoOPTIMIZE: An open-label, phase II trial and biomarker discovery platform to assess the efficacy of adaptive switching of modified FOLFIRINOX (mFFX) or gemcitabine/nab-paclitaxel (GA) as a neoadjuvant strategy for patients with resectable/borderline resectable and locally advanced unresectable pancreatic ductal adenocarcinoma (PDAC)

TPS630

Background: Neoadjuvant chemotherapy (NAC) and/or chemo-RT may confer benefit to patients with localized PDAC, by better tolerability, tumor down-staging, and increased R0 resections. mFFX or GA are the current NAC backbones; however, a lack of robust predictive biomarker(s) hampers identification of patients most likely to benefit from mFFX or GA. Further, desmoplastic stroma/poor vascularity compromise NAC efficacy, but angiotensin II receptor inhibitor, losartan, might remodel vascular perfusion to enhance chemotherapy activity. We designed the NeoOPTIMIZE trial for patients with newly diagnosed localized PDAC to provide a flexible clinical platform to: 1) evaluate the feasibility and efficacy of early switching of mFFX to GA, and 2) establish a robust biomarker/imaging discovery platform to optimize the NAC backbone. Methods: NeoOPTIMIZE is an open-label, non-randomized, phase II trial to assess the efficacy of an adaptive treatment strategy that allows for early switching of NAC in patients with localized PDAC. Sixty patients (n = 40 resectable/BRCP; n = 20 locally advanced unresectable [uLAPC]) will be enrolled to receive 2 months of preoperative mFFX (oxaliplatin, 85 mg/m2; folinic acid, 400 mg/m2; irinotecan, 150 mg/m2; 5-FU, 2400 mg/m2), then restaging by a multidisciplinary tumor board (multiD-TB). Absent progression (by panc protocol CT and CA19-9 decline/increase < 30% from baseline), patients continue mFFX (4 cycles). If progression (by panc protocol CT; CA19-9 increase > 30%), patients switch to GA (nab-paclitaxel, 125 mg/m2; gemcitabine, 1000 mg/m2) for 2 months. After 4 months of mFFX or mFFX/GA, another restaging multiD-TB will decide to proceed with: a) RT (if vascular involvement) then resection, b) resection, or c) continued chemo (if unresectable). Losartan (50 mg PO QD) is given throughout NAC and RT regimens. The primary endpoint estimates the proportion of resectable/BRPC patients with R0 resection. Assuming that the proportion of R0 is 60%, a sample size of 32 will provide a 95% CI of 0.41 - 076. To account for a 20% dropout, 40 patients will be enrolled towards primary endpoint. A separate exploratory cohort of 20 uLAPC patients will be enrolled. Secondary endpoints include DFS, PFS, OS, and AEs. Exploratory objectives include correlating clinical outcomes data with changes in blood-based biomarkers (CA19-9, ctDNA, circulating tumor cells etc.) and research DCE-MRI. We are collecting tumors to correlate deep multi-omic analytics with clinical data. The study is open with 6 patients enrolled at time of submission. Clinical trial information: NCT04539808.

Phase II study of preoperative chemotherapy with nab-paclitaxel and gemcitabine followed by chemoradiation for borderline resectable or node-positive pancreatic ductal adenocarcinoma

697

Background: Pre-operative therapy for resectable pancreatic ductal adenocarcinoma (PDAC) may eliminate micro-metastatic disease early and help achieve negative surgical margins. The present study is based on the hypothesis that gemcitabine/nab-paclitaxel chemotherapy followed by chemo-radiation with fluoropyrimidine is a feasible and efficacious pre-operative treatment for borderline resectable or node-positive PDAC. Methods: This is a single-arm phase II trial to evaluate pre-operative treatment with 2 cycles of gemcitabine 1000 mg/m2 and nab-paclitaxel 125 mg/m2 on days 1, 8, 15 every 28 days followed by 50.4 Gy of intensity-modulated radiation therapy over 28 fractions with concurrent 5-fluorouracil or capecitabine prior to pancreatic resection. Patients were eligible if they met borderline resectable criteria or had abnormal regional nodes visible on contrast CT. After surgery, they were eligible to receive up to 4 additional cycles of gemcitabine/nab-paclitaxel. The primary endpoint was the R0 resection rate. Secondary endpoints included response to pre-operative therapy, overall toxicities, relapse-free survival, and overall survival. Results: Nineteen of 24 screened patients have been enrolled. Median age was 68, 10 (53%) were female, and 4 (21%) were non-Caucasian. Eleven (78%) had head of pancreas cancers, 13 (68%) exhibited both arterial and venous involvement, and 12 (63%) had positive clinical nodes. All 19 patients received 2 months of gemcitabine/nab-paclitaxel, of which 17 patients continued to chemo-radiation (1 developed metastatic disease and 1 moved out of state). In the interval between chemo-radiation and surgery, 3 developed metastatic disease, 1 became unresectable, 1 withdrew from study, and 1 was deemed too frail for surgery. Nine have undergone successful pancreatic resection, and 2 are pending resection. Conclusions: Pre-operative gemcitabine/nab-paclitaxel followed by chemo-radiation with fluoropyrimidine is feasible in patients with borderline resectable PDAC and represents another strategy to FOLFIRINOX-based therapy. A planned interim analysis is ongoing. Clinical trial information: NCT02427841.

Perioperative complication rates following neoadjuvant therapy in pancreatic adenocarcinoma

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Background: Whether upfront resection or total neoadjuvant therapy is superior for the treatment of potentially resectable pancreatic adenocarcinoma (PDAC) remains controversial. The impact of neoadjuvant treatment on major perioperative complication rates for patients (pts) undergoing resection for PDAC is commonly debated. We hypothesized that rates would be comparable among patients receiving neoadjuvant chemoradiation (neo-CRT), neoadjuvant chemotherapy alone (neo-CHT), or upfront surgery. Methods: This is a retrospective study of 208 pts with PDAC who underwent resection within a multidisciplinary pancreatico-biliary program at an academic tertiary referral center between 2011-2018. Data were abstracted from the medical record, an institutional cancer registry and NSQIP databases. Outcomes were assessed using χ2, Fisher’s exact test and two-tailed Student’s t-tests. Results: 208 pts were identified: 33 locally advanced, borderline or upfront resectable pts underwent neo-CRT, 35 borderline or resectable pts underwent neoadjuvant-CHT, and 140 resectable pts did not undergo neoadjuvant therapy. There were no statistically significant differences in major perioperative complication rates between groups. Overall rates were 36.4%, 34.3%, and 26.4% for pts who underwent neo-CRT, neo-CHT alone, or upfront resection, respectively (p = 0.38). No significant difference were observed in complication rates (35.3% v. 26.4%; p = 0.19) or median hospital length of stay (10 days v. 10 days; p = 0.87) in pts who received any neoadjuvant therapy versus upfront resection. There were two perioperative deaths in the neo-CRT group (6.1%), zero in the neo-CHT group, and four in the upfront resection group (2.9%); p = 0.22. Conclusions: There were no significant differences in major perioperative complication rates, hospital length of stay, or post-operative mortality in pts who underwent neoadjuvant therapy (neo-CRT or neo-CHT alone) versus upfront surgery. Notably, neo-CRT had comparable perioperative complication rates to neo-CHT alone, which suggests neoadjuvant radiation therapy may not pose additional surgical risk.

Appendiceal cancer masked as inflammatory appendicitis in the elderly, not an uncommon presentation (Surveillance Epidemiology and End Results (SEER)-Medicare Analysis)

BACKGROUND

The misdiagnosis of appendiceal cancer as inflammatory appendicitis is becoming of greater clinical concern because of the rise of nonoperative management especially in the elder population. To quantify this rate of misdiagnosis, we retrospectively reviewed SEER-Medicare data.

METHODS

The SEER-Medicare database was reviewed from 2000 to 2014. We identified patients older than 65 years old who were diagnosed with appendiceal cancer and then cross-referenced them for a diagnosis of inflammatory appendicitis. Demographic data and oncologic stage were collected.

RESULTS

Our results showed that 28.6% of appendiceal cancer patients received an incorrect initial diagnosis of inflammatory appendicitis. Patients older than 75 years of age were more likely to be misdiagnosed than those between ages 65 and 75 (risk ratio [RR]: 0.81; 95% confidence interval: 0.70-0.93; P = .003). We found that 42% of patients within the misdiagnosis group presented with an earlier stage of disease (stage 1 or 2) compared to 26% of those primarily diagnosed with appendiceal cancer (P < .001).

CONCLUSION

A significant proportion of patients older than 65 years old with appendiceal cancer were initially misdiagnosed with acute appendicitis. We suggest caution when considering a nonoperative approach for appendicitis in the elderly and follow-up imaging or an interval appendectomy should be part of the treatment plan.

Pheochromocytoma: 20 years of improving surgical care

BACKGROUND

Laparoscopic adrenalectomy is now the standard for pheochromocytoma. We report two decades of institutional experience with pheochromocytoma adrenalectomy.

METHODS

A retrospective review was undertaken of pheochromocytoma adrenalectomy patients between 1997 and 2017. Clinical variables and postoperative complications were recorded. Patients were divided into quartiles for analysis: group 1 from 1997 to 2001, group 2 from 2002 to 2006, group 3 from 2007 to 2011, and group 4 from 2012 to 2017.

RESULTS

Eighty-two pheochromocytoma adrenalectomies were identified. The percentage of laparoscopic adrenalectomies increased over time: 60% in group 1-87.5% in group 4 (p = 0.03). The average tumor size decreased: 6.4 cm (2.8-14.3 cm) in group 1-4.6 cm (1.2-7.8 cm) in group 4 (p = 0.03). ICU utilization decreased from 80% to 40.6% (p = 0.03) and length of stay decreased from 7.2 days to 2.7 days (p = 0.005). Clavien-Dindo grade>3 complications did not differ between the quartiles (p = 0.08).

CONCLUSION

Pheochromocytoma care has evolved from more open procedures with standard postoperative ICU stay to a laparoscopic resection with targeted ICU care and decreased length of stay. As experience with laparoscopic adrenalectomy increases, patient outcomes improve.

Who Undergoes Cytoreductive Surgery and Perioperative Intraperitoneal Chemotherapy for Appendiceal Cancer? An Analysis of the National Cancer Database

BACKGROUND

We sought to identify patterns of care for patients with appendiceal cancer and identify clinical factors associated with patient selection for multimodality treatment, including cytoreductive surgery and perioperative intraperitoneal chemotherapy (CRS/PIC).

MATERIALS AND METHODS

National Cancer Database (NCDB) data from 2004 to 2014 of all diagnoses of appendiceal cancers were examined. We examined treatment modalities, as well as demographic, tumor-specific, and survival data. A multivariate logistic regression analysis was performed to determine the patient cohort most likely to receive CRS/PIC. Kaplan-Meier was used to estimate survival for all treatment groups. Significance was evaluated at P ≤ 0.05.

RESULTS

We analyzed data on 18,055 patients. Nine thousand nine hundred ninety-two (55.3%) were treated with surgery only, 5848 (32.4%) received surgery and systemic chemotherapy, 1393 (7.71%) received CRS/PIC, 520 (2.88%) received chemotherapy alone, and 302 (1.67%) received neither surgery nor chemotherapy. Significant predictors of receiving CRS/PIC included male sex (OR 1.33, 95% CI: 1.11-1.59), white race (OR 2.00, 95% CI 1.40-2.86), non-Hispanic ethnicity (OR 1.92, 95% CI 1.21-3.05), private insurance (OR 1.52, 95% CI 1.26-1.84), and well-differentiated tumors (OR 4.25, CI: 3.39-5.32) (P < 0.05). Treatment with CRS/PIC was associated with a higher 5-year survival for mucinous malignancies, when compared to surgery alone (65.6% versus 62.4%, P < 0.01). Treatment with CRS/PIC was also associated with higher 5-year survival for well-differentiated malignancies, when compared to all other treatment modalities (74.9% versus 65.4%, P < 0.01).

CONCLUSIONS

Patients were more likely to undergo CRS/PIC if they were male, white, privately insured, and with well-differentiated tumors. CRS/PIC was associated with improved survival in patients with mucinous and low-grade tumors.

Laparoscopic vagal nerve blocking device explantation: case series and report of operative technique

BACKGROUND

Vagal nerve blockade with the vBloc device (ReShape Lifesciences, St. Paul, MN) has been shown to provide durable 2-year weight loss in patients with moderate obesity. These devices may require removal. We present a series of patients and report our technique for laparoscopic removal of this device.

METHODS

From December 2009 to December 2016, the medical records of patients who underwent laparoscopic explantation of a vagal blocking device at our institution were retrospectively reviewed. All patients initially underwent device placement as part of a multi-center, randomized, controlled trial. The device leads were removed with the application of firm traction in order to safely dissect them away from the stomach and esophagus as the body tended to form a fibrotic capsule surrounding the leads. Operative details, length of stay, 30-day post-operative complications, demographics and reasons for device removal were reported.

RESULTS

Thirty patients were identified. Median age was 54 (37-65) years. Average operative time was 227.63 (± 100.21) min. Median time from implantation to removal was 41 (11-96) months. Removal reasons included device malfunction (7 patients, 23.3%), pain at the neuroregulator site (5 patients, 16.7%), retrosternal or epigastric pain (11 patients, 36.7%), weight regain or dissatisfaction with weight loss (15 patients, 50%), and severe nausea (2 patients, 6.7%). Two patients (6.7%) had Clavien-Dindo grade II complications following explantation. Thirteen patients (43.3%) had dense adhesions noted at the time of operation. Seroma formation at the neuroregulator site was the most common complication (7 patients, 23.3%).

CONCLUSION

The vagal nerve blocking device can be safely removed laparoscopically with a low 30-day complication rate. Surgeons should be familiar with the details of the device appearance, the typical lead location, and should anticipate dense adhesions surrounding the leads. In addition, experience operating in the region of the gastroesophageal junction is imperative.

Appendiceal Neoplasms

Appendiceal neoplasms are identified in 0.9 to 1.4% of appendiceal specimens, and the incidence is increasing. It has long been professed that neuroendocrine tumors (formerly carcinoids) are the most common neoplastic process of the appendix; recent data, however, has suggested a shift in epidemiology. Our intent is to distill the complex into an algorithm, and, in doing so, enable the surgeon to seamlessly maneuver through operative decisions, treatment strategies, and patient counseling. The algorithm for evaluation and treatment is complex, often starts from the nonspecific presenting complaint of appendicitis, and relies heavily on often subtle histopathologic differences.

Evolution in the Treatment of Esophageal Disease at a Single Academic Institution: 2004-2013

INTRODUCTION

Management of benign and malignant esophageal disease has changed rapidly over the past decade. The aim of this study was to analyze evolution in surgical management of esophageal disease at a single academic medical center during this period.

MATERIALS AND METHODS

We reviewed a retrospective cohort of patients who underwent esophagectomy between 2004 and 2013. Patient, institutional, treatment, and outcomes variables were reviewed.

RESULTS

317 patients were analyzed. Median age was 63.5 years; 80% were male. Average inhospital mortality rate was 3.8%. Operative indications changed significantly from 2004 to 2013, with more operations performed for invasive malignancy (77% vs. 95%) and fewer for high-grade dysplasia (12% vs. 3%, P = .008). In 2004, Ivor Lewis esophagectomy was the most common surgical technique, but the three-field technique was the operation of choice in 2013. A minimally invasive approach was used in 19% of cases in 2004 and 100% of cases in 2013 (P < .001). Anastomotic leak ranged from 0% to 21% with no significant difference over the study period (P = .18). Median lymph node harvest increased from seven to 18 nodes from 2004 to 2013 (P = .001). Hospital length of stay decreased from 15 to 8 days (P = .001). In 2013, 79% of patients were discharged to home, compared to 73% in 2004 (P = .04).

DISCUSSION

Over the last decade, our treatment of esophageal disease has evolved from a predominantly open Ivor Lewis to a minimally invasive three-field approach. Operations for malignancy have also increased dramatically. Postoperative complications and mortality were not significantly changed, but were consistently low during the latter years of the study.

Abstract B84: Physiologic pancreatic cancer imaging using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI)

Background: Accurately identifying and monitoring pancreatic ductal adenocarcinoma (PDA) remains a significant challenge. Whereas conventional imaging (CT and MRI) report only anatomic information, dynamic contrast-enhanced MRI (DCE-MRI) has the ability to show physiologic differences in tissue perfusion based on the kinetics of IV-contrast. We coupled DCE-MRI with data-modeling methods to obtain reproducible, high-resolution physiologic images in a series of patients with and without PDA in order to more accurately identify PDA.

Methods: Patients with borderline-resectable PDA (BR-PDA) or at high-risk for PDA (HR), but without cancer were imaged with DCE-MRI. T1-weighted images were collected during IV contrast injections [Figure 1]. Both tumor and the pancreatic body or non-tumor pancreas were identified and using dual-compartment pharmacokinetic modelling, DCE-MRI parameters were quantified and compared between groups.

Results: Between 6/2014 and 2/2015, 12 DCE-MRIs were completed: 9 HR and 3 BR-PDA. Significant differences in the DCE-MRI parameters blood flow (F), first-pass extraction (E), mean capillary transit-time (tc), transfer constant (Ktrans), volume of extravascular-extracellular space (Ve) and blood volume (Vb) were found in normal HR pancreases vs. the tumors in BR-PDA patients [Table 1A]. When comparing non-tumoral pancreases in both cohorts, only F, Ktrans, and Vb differed [Table 1B].

Conclusions: DCE-MRI of the pancreas is feasible and provides imaging biomarkers of vascular structure and function in both tumoral and non-tumoral pancreases which may allow for earlier and more accurate identification of PDA in these high risk populations.

Citation Format: Laura E. Fischer, Matthias Schabel, Bryan Foster, Charles R. Thomas, Jr., William Rooney, Brett C. Sheppard, Erin W. Gilbert.{Authors}. Physiologic pancreatic cancer imaging using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer: Advances in Science and Clinical Care; 2016 May 12-15; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2016;76(24 Suppl):Abstract nr B84.

Evolution in the treatment of esophageal disease at a single institution: 2004-2013

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Background: The aim of this study was to analyze the evolution in the surgical management of esophageal disease at an academic medical center during the last decade. Methods: We reviewed a retrospective cohort of patients who underwent esophagectomy between 2004 and 2013 for benign and malignant esophageal disease. Patient, institutional and postoperative variables were abstracted and reviewed across the study period. Results: 317 patients were analyzed. The median age was 63.5 years and 80% were male. Malignancy accounted for 88% of esophagectomy patients in 2004 and 97% in 2013. Operations for high grade dysplasia (HGD) decreased 75% in the same period (p=0.008). In 2004, an Ivor Lewis esophagectomy was the most common surgical technique but the 3-Field technique has become the operation of choice in 2013 (54% vs.71%, p<0.001). Likewise, a laparoscopic approach was used in 19% of cases in 2004 and 100% of cases in 2013 (p<0.001). Median lymph node harvest increased from 7 to 18 nodes (p=0.001). Atrial fibrillation was the most common perioperative complication (24%) and anastomotic leaks ranged between 3 to 14% (p=0.18), occurring in 3% of patients in 2013. Hospital stay decreased from 15 to 8 days over the study period (p=0.001). In 2013, 89% of patients were discharge to home compared to 73% in 2004 (p=0.04). The average mortality rate for our cohort was 3.5%. Conclusions: Over the last decade, our treatment of esophageal disease has evolved from a predominant open Ivor Lewis to a laparoscopic 3-Field approach. Operations for malignancy have also increased dramatically. Postoperative complications and mortality has been consistently low during the latter years of the study.

Symmetrical Cortical Necrosis of the Kidneys: Report of a Case

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