Neoadjuvant Therapy for Pancreatic Ductal Adenocarcinoma: Propensity-Matched Analysis of Postoperative Complications Using ACS-NSQIP

Neoadjuvant Chemotherapy is Associated with Increased Risk of Postoperative DVT After Distal Pancreatectomy for Pancreatic Adenocarcinoma: a NSQIP Analysis

BACKGROUND

Venous thromboembolism (VTE) remains a persistent source of postoperative morbidity despite prevention and mitigation efforts. Cancer, surgery, and chemotherapy are known risk factors for VTE. Existing literature suggests that neoadjuvant therapy (NAT) may contribute to increased VTE risk in the postoperative period, but few authors specifically examine this relationship in distal pancreatic adenocarcinoma (PDAC). In this study, we analyze the association of NAT and postoperative VTE in patients who underwent distal pancreatectomy (DP) for PDAC.

PATIENTS AND METHODS

Using the American College of Surgeons (ACS) National Surgical Quality Improvement Program (NSQIP) database, we analyzed the Procedure Targeted files for pancreatectomy from 2014 to 2020. Adults with PDAC who underwent DP were grouped by receipt of NAT. The primary outcome was the rate of deep venous thrombosis (DVT) and the secondary outcome was the rate of pulmonary embolism (PE). We performed univariate and multivariate logistic regression analysis to determine risk factors associated with postoperative DVT.

RESULTS

There were 4327 patients with PDAC who underwent DP. Of these, 1414 (32.7%) had NAT. Receipt of NAT was significantly associated with postoperative DVT requiring therapy (3.5% vs. 2.3%, p = 0.02), but was not associated with PE (p = 0.42). On MVA, NAT was associated with a 73% greater chance of developing postoperative DVT [odds ratio (OR) 1.73, 95% CI 1.18-2.55].

CONCLUSIONS

Patients who receive NAT prior to DP for PDAC are 73% more likely to develop postoperative DVT compared with upfront resection. As NAT becomes more commonplace, these high-risk patients should be prioritized for guideline-recommended extended duration prophylaxis.

A Machine Learning Approach to Predict Postoperative Pancreatic Fistula After Pancreaticoduodenectomy Using Only Preoperatively Known Data

BACKGROUND

Clinically-relevant postoperative pancreatic fistula (CR-POPF) following pancreaticoduodenectomy (PD) is a major postoperative complication and the primary determinant of surgical outcomes. However, the majority of current risk calculators utilize intraoperative and postoperative variables, limiting their utility in the preoperative setting. Therefore, we aimed to develop a user-friendly risk calculator to predict CR-POPF following PD using state-of-the-art machine learning (ML) algorithms and only preoperatively known variables.

METHODS

Adult patients undergoing elective PD for non-metastatic pancreatic cancer were identified from the ACS-NSQIP targeted pancreatectomy dataset (2014-2019). The primary endpoint was development of CR-POPF (grade B or C). Secondary endpoints included discharge to facility, 30-day mortality, and a composite of overall and significant complications. Four models (logistic regression, neural network, random forest, and XGBoost) were trained, validated and a user-friendly risk calculator was then developed.

RESULTS

Of the 8666 patients who underwent elective PD, 13% (n = 1160) developed CR-POPF. XGBoost was the best performing model (AUC = 0.72), and the top five preoperative variables associated with CR-POPF were non-adenocarcinoma histology, lack of neoadjuvant chemotherapy, pancreatic duct size less than 3 mm, higher BMI, and higher preoperative serum creatinine. Model performance for 30-day mortality, discharge to a facility, and overall and significant complications ranged from AUC 0.62-0.78.

CONCLUSIONS

In this study, we developed and validated an ML model using only preoperatively known variables to predict CR-POPF following PD. The risk calculator can be used in the preoperative setting to inform clinical decision-making and patient counseling.

Radiation therapy prior to a pancreaticoduodenectomy for adenocarcinoma is associated with longer operative times and higher blood loss

BACKGROUND

Pancreatic adenocarcinoma is currently the fourth leading cause of cancer-related deaths in the United States. In patients with "borderline resectable" disease, current National Comprehensive Cancer Center guidelines recommend the use of neoadjuvant chemoradiation prior to a pancreaticoduodenectomy. Although neoadjuvant radiotherapy may improve negative margin resection rate, it is theorized that its administration increases operative times and complexity.

AIM

To investigate the association between neoadjuvant radiotherapy and 30-d morbidity and mortality outcomes among patients receiving a pancreaticoduodenectomy for pancreatic adenocarcinoma.

METHODS

Patients listed in the 2015-2019 National Surgery Quality Improvement Program data set, who received a pancreaticoduodenectomy for pancreatic adenocarcinoma, were divided into two groups based off neoadjuvant radiotherapy status. Multivariable regression was used to determine if there is a significant correlation between neoadjuvant radiotherapy, perioperative blood transfusion status, total operative time, and other perioperative outcomes.

RESULTS

Of the 11458 patients included in the study, 1470 (12.8%) underwent neoadjuvant radiotherapy. Patients who received neoadjuvant radiotherapy were significantly more likely to require a perioperative blood transfusion [adjusted odds ratio (aOR) = 1.58, 95% confidence interval (CI): 1.37-1.82; P < 0.001] and have longer surgeries (insulin receptor-related receptor = 1.14, 95%CI: 1.11-1.16; P < 0.001), while simultaneously having lower rates of organ space infections (aOR = 0.80, 95%CI: 0.66-0.97; P = 0.02) and pancreatic fistula formation (aOR = 0.50, 95%CI: 0.40-0.63; P < 0.001) compared to those who underwent surgery alone.

CONCLUSION

Neoadjuvant radiotherapy, while not associated with increased mortality, will impact the complexity of surgical resection in patients with pancreatic adenocarcinoma.

Preoperative treatments in borderline resectable and locally advanced pancreatic cancer: current evidence and new perspectives

Surgery is the only curative treatment for non-metastatic pancreatic adenocarcinoma, but less than 20% of patients present a resectable disease at diagnosis. Treatment strategies and disease definition for borderline resectable pancreatic cancer (BRPC) and locally advanced pancreatic cancer (LAPC) vary in the different cancer centres. Preoperative chemotherapy (CT) is the standard of care for both BRPC and LAPC patients, however literature data are still controversial concerning the type, dose and duration of the different CT regimens, as well as regarding the integration of radiotherapy (RT) or chemoradiation (CRT) in the therapeutic algorithm. In this unsettled debate, we aimed at focusing on the therapeutic regimens currently in use and relative literature data, to report international trials comparing the available therapeutic options or explore the introduction of new pharmacological agents, and to analyse possible new scenarios in microenvironment evaluation before and after neoadjuvant therapies or in patients' selection at a molecular level.

Impact of Extended Antibiotic Use After Pancreaticoduodenectomy for Patients with Preoperative Metallic Biliary Stenting Treated with Neoadjuvant Chemotherapy

INTRODUCTION

Pancreaticoduodenectomy (PD) remains a complex surgical procedure with infectious complications affecting nearly 50% of patients. Patients who undergo biliary drainage with stent placement prior to neoadjuvant treatment (NAT) reportedly have higher infection rates following PD. The aim of the current study is to evaluate the differences in postoperative infectious complication rates based on the duration of post operative prophylactic antibiotics in patients with indwelling metal biliary stent who had NAT.

METHODS

A retrospective institutional pancreatic cancer database was queried for patients who had a metal biliary stent placed prior to NAT initiation, followed by subsequent PD between 2014 and 2021. Duration of postoperative prophylactic antibiotics was defined as short (SC: ≤ 24 h) or extended (EC: > 24 h-7 days). The primary outcome of interest was surgical site infection (SSI).

RESULTS

Two hundred and ninety-five (n = 295) patients were identified of which the majority (n = 205, 69.5%) received a short course of antibiotics postoperatively. Baseline characteristics were similar between the two cohorts including age, sex, BMI, and comorbidity index. EC patients received more NAT cycles (4 vs. 3, p < 0.001) and underwent an open PD more frequently (61.8% vs. 41.0%, p < 0.001). SSI occurred in 64 (21.7%) patients; SC cohort: 54, 26.3% vs. EC cohort:10, 11.1%, (p = 0.003). Additionally, the SC cohort demonstrated a higher incidence of major complications (Clavien-Dindo ≥ 3: 51 [24.9%] vs. 13 [14.4%], p = 0.045). On the logistic regression model examining factors associated with SSI, higher BMI (continuous variable) was associated with increased odds of SSI (OR: 1.05 [95%CI: 1.00, 1.10, p = 0.040), while EC was protective (OR: 0.36 [95%CI: 0.17, 0.75], p = 0.007).

CONCLUSIONS

These data suggest that an extended course of perioperative antibiotic correlates with reductions in SSI and major morbidity following PD in patients with a metallic biliary stent placed prior to NAT course. These results require validation in a future randomized clinical trial examining a larger cohort of patients with further emphasis on the types of perioperative antibiotics administered.

Is it safe to administer neoadjuvant chemotherapy to patients undergoing hepatectomy for intrahepatic cholangiocarcinoma? ACS-NSQIP propensity-matched analysis

BACKGROUND

The use of neoadjuvant chemotherapy (NAC) in patients with intrahepatic cholangiocarcinoma (iCCA) is increasing. The objective of this study was to compare the 30-day post-operative complications and length-of-stay (LOS) between patients undergoing hepatectomy for iCCA with and without NAC.

METHODS

A retrospective study was conducted using the ACS-NSQIP database queried from 2014 to 2018. Patients with NAC receipt were propensity-score matched into 1:3 ratio with controls using the greedy-matching algorithm and a caliper of 0.2. Logistic and Poisson regression models were used to estimate the effect sizes.

RESULTS

A total of 1508 patients who underwent hepatectomy for iCCA were included. 706 patients remained after matching and balance were achieved. The NAC group had 110 (60.1%) complications vs. 289 (55.3%) complications in the non-NAC group (p = 0.29). NAC was not associated with worse 30-day postoperative complications [OR 1.24, 95% CI: 0.87-1.76; p = 0.24]. Post-operative LOS in the NAC group was 8.56 days (mean, SD 7.4) vs. non-NAC group 9.27 days (mean, SD 8.41, p = 0.32). NAC was not associated with longer post-operative LOS [RR 0.93, 95% CI:0.80, 1.08; p = 0.32].

CONCLUSION

NAC may be safely administered without increasing the risk of 30-day complications or post-operative hospital LOS.

The timing and design of stereotactic radiotherapy approaches as a part of neoadjuvant therapy in pancreatic cancer: Is it time for change?

Stereotactic Radiotherapy (SRT) over 5-15 days can be interdigitated without delaying chemotherapy. Bridging chemotherapy may allow for extended intervals to surgery, potentially improving sterilization of surgical margins and overall survival. SRT for pancreatic adenocarcinoma should not be limited to the tumor, and should consider hypofractionated approaches to regional nodes.

Association of gravity drainage and complications following Whipple: an analysis of the ACS-NSQIP targeted database

Background

The optimal type of operative drainage following pancreaticoduodenectomy (PD) remains unclear. Our objective is to investigate risk associated with closed drainage techniques (passive [gravity] vs. suction) after PD.

Methods

We assessed operative drainage techniques utilized in patients undergoing PD in the ACS-NSQIP pancreas-targeted database from 2016 to 2018. Using multivariable logistic regression to adjust for characteristics of the patient, procedure, and pancreas, we examined the association between use of gravity drainage and postoperative outcomes.

Results

We identified 9665 patients with drains following PD from 2016 to 2018, of which 12.7% received gravity drainage. 61.0% had a diagnosis of adenocarcinoma or pancreatitis, 26.5% had a duct <3 mm, and 43.5% had a soft or intermediate gland. After multivariable adjustment, gravity drainage was associated with decreased rates of postoperative pancreatic fistula (odds ratio [OR] 0.779, 95% confidence interval [CI] 0.653–0.930, p=0.006), delayed gastric emptying (OR 0.830, 95% CI 0.693–0.988, p=0.036), superficial SSI (OR 0.741, 95% CI 0.572–0.959, p=0.023), organ space SSI (OR 0.791, 95% CI 0.658–0.951, p=0.012), and readmission (OR 0.807, 95% CI 0.679–0.958, p=0.014) following PD.

Conclusions

Gravity drainage is independently associated with decreased rates of CR-POPF, DGE, SSI, and readmission following PD. Additional prospective research is necessary to better understand the preferred drainage technique following PD.