Defining the Minimal and Optimal Thresholds for Lymph Node Resection and Examination for Intraductal Papillary Mucinous Neoplasm Derived Pancreatic Cancer: A Multicenter Retrospective Analysis

OBJECTIVE

To establish minimal and optimal lymphadenectomy thresholds for intraductal papillary mucinous neoplasm (IPMN)-derived pancreatic ductal adenocarcinoma (PDAC) and evaluate their prognostic value.

BACKGROUND

Current guidelines recommend a minimum of 12-15 lymph nodes (LNs) in PDAC. This is largely based on pancreatic intraepithelial neoplasia (PanIN)-derived PDAC, a biologically distinct entity from IPMN-derived PDAC.

METHODS

Multicenter retrospective study including consecutive patients undergoing upfront surgery for IPMN-derived PDAC was conducted. The minimum cut-off for lymphadenectomy was defined as the maximum number of LNs where a significant node positivity difference was observed. Maximally selected log-rank statistic was used to derive the optimal lymphadenectomy cut-off (maximize survival). Kaplan-Meier curves and log-rank tests were used to analyze overall survival (OS) and recurrence-free survival (RFS). Multivariable Cox-regression was used to determine hazard ratios (HR) with 95% confidence intervals (95%CI).

RESULTS

In 341 patients with resected IPMN-derived PDAC, the minimum number of LNs needed to ensure accurate nodal staging was 10 (P=0.040), whereas ≥20 LNs was the optimal number associated with improved OS (80.3 vs. 37.2 mo, P<0.001). Optimal lymphadenectomy was associated with improved OS [HR:0.57 (95%CI 0.39-0.83)] and RFS [HR:0.70 (95%CI 0.51-0.97)] on multivariable Cox-regression. On sub-analysis the optimal lymphadenectomy cut-offs for pancreatoduodenectomy, distal pancreatectomy, and total pancreatectomy were 20 (P<0.001), 23 (P=0.160), and 25 (P=0.008).

CONCLUSION

In IPMN-derived PDAC, lymphadenectomy with at least 10 lymph nodes mitigates under-staging, and at least 20 lymph nodes is associated with the improved survival. Specifically, for pancreatoduodenectomy and total pancreatectomy, 20 and 25 lymph nodes were the optimal cut-offs.

Association of Triglyceride and C-reactive Protein Level with Severity of Angiographically Defined Coronary Artery Disease

Coronary artery disease (CAD) is considered as a major cause of morbidity and mortality worldwide. Inflammatory cytokines play an important role in the pathogenesis and progression of atherosclerosis. The aim of the study was to find out the association of C-reactive protein (CRP) and triglyceride (TG) level on the severity of CAD in patients with ischemic heart disease (IHD). This cross-sectional study was performed in the Department of Cardiology, National Institute of Cardiovascular Diseases, Dhaka, Bangladesh during the period of March 2018 to February 2021. Total 431 patients with ischemic heart disease were enrolled after taking informed written consent. CRP values were categorized into normal (<6 mg/L), borderline (6-10 mg/L) and high (>10mg/L) and TG level were categorized into normal (<150 mg/dl), borderline (150-199mg/dl) and high (≥200 mg/dl). Patients with ischemic heart disease (IHD) were stratified according to CRP value and TG level. Severity of CAD was assessed by the Gensini score. Most of the patients (33.4%) belonged to age 51-60 years. The mean age was 51.31±10.30 years. The majority (74.5%) of patients were male. Among risk factors, the highest 205(47.6%) patients were smokers followed by hypertension 190(44.1%) and diabetes mellitus 175(40.5%). The association of TG and CRP with the whole spectrum of IHD was found statistically significant (p<0.05). Severe CAD was found higher in high TG and high CRP level group compared with the other groups and was statistically significant. Inflammation assessed by high CRP and hypertriglyceridemia associated with the risk and severity of CAD.

Factors associated with radiological misstaging of pancreatic ductal adenocarcinoma: A retrospective observational study

PURPOSE

Accurate staging of disease is vital in determining appropriate care for patients with pancreatic ductal adenocarcinoma (PDAC). It has been shown that the quality of scans and the experience of a radiologist can impact computed tomography (CT) based assessment of disease. The aim of the current study was to evaluate the impact of the rereading of outside hospital (OH) CT by an expert radiologist and a repeat pancreatic protocol CT (PPCT) on staging of disease.

METHODS

Patients evaluated at the our institute's pancreatic multidisciplinary clinic (2006 to 2014) with OH scan and repeat PPCT performed within 30 days were included. In-house radiologists staged disease using OH scans and repeat PPCT, and factors associated with misstaging were determined.

RESULTS

The study included 100 patients, with a median time between OH scan and PPCT of 19 days (IQR: 13-23 days.) Stage migration was mostly accounted for by upstaging of disease (58.8 % to 83.3 %) in all comparison groups. When OH scans were rereviewed, 21.5 % of the misstaging was due to missed metastases, however, when rereads were compared to the PPCT, occult metastases accounted for the majority of misstaged patients (62.5 %). Potential factors associated with misstaging were primarily related to imaging technique.

CONCLUSION

A repeat PPCT results in increased detection of metastatic disease that rereviews of OH scans may otherwise miss. Accessible insurance coverage for repeat PPCT imaging even within 30 days of an OH scan could help optimize delivery of care and alleviate burdens associated with misstaging.

The Role of Intraoperative Pancreatoscopy in the Surgical Management of Intraductal Papillary Mucinous Neoplasms: A Scoping Review

OBJECTIVES

Most patients with intraductal papillary mucinous neoplasms (IPMNs) are diagnosed with a solitary lesion; however, the presence of skip lesions, not appreciable on imaging, has been described. Postoperatively, these missed lesions can continue to grow and potentially become cancerous. Intraoperative pancreatoscopy (IOP) may facilitate detection of such skip lesions in the remnant gland. The aim of this scoping review was to appraise the evidence on the role of IOP in the surgical management of IPMNs.

MATERIALS AND METHODS

Studies reporting on the use of IOP during IPMN surgery were identified through searches of the PubMed, Embase, and Scopus databases. Data extracted included IOP findings, surgical plan modifications, and patient outcomes. The primary outcome of interest was the utility of IOP in surgical decision making.

RESULTS

Ten studies reporting on the use of IOP for IPMNs were identified, representing 147 patients. A total of 46 skip lesions were identified by IOP. Overall, surgical plans were altered in 37% of patients who underwent IOP. No IOP-related complications were reported.

CONCLUSIONS

The current literature suggests a potential role of integration of IOP into the management of patients with IPMNs. This tool is safe and feasible and can result in changes in surgical decision making.

Deep neural network-based segmentation of normal and abnormal pancreas on abdominal CT: evaluation of global and local accuracies

PURPOSE

Delay in diagnosis can contribute to poor outcomes in pancreatic ductal adenocarcinoma (PDAC), and new tools for early detection are required. Recent application of artificial intelligence to cancer imaging has demonstrated great potential in detecting subtle early lesions. The aim of the study was to evaluate global and local accuracies of deep neural network (DNN) segmentation of normal and abnormal pancreas with pancreatic mass.

METHODS

Our previously developed and reported residual deep supervision network for segmentation of PDAC was applied to segment pancreas using CT images of potential renal donors (normal pancreas) and patients with suspected PDAC (abnormal pancreas). Accuracy of DNN pancreas segmentation was assessed using DICE simulation coefficient (DSC), average symmetric surface distance (ASSD), and Hausdorff distance 95% percentile (HD95) as compared to manual segmentation. Furthermore, two radiologists semi-quantitatively assessed local accuracies and estimated volume of correctly segmented pancreas.

RESULTS

Forty-two normal and 49 abnormal CTs were assessed. Average DSC was 87.4 ± 3.1% and 85.5 ± 3.2%, ASSD 0.97 ± 0.30 and 1.34 ± 0.65, HD95 4.28 ± 2.36 and 6.31 ± 6.31 for normal and abnormal pancreas, respectively. Semi-quantitatively, ≥95% of pancreas volume was correctly segmented in 95.2% and 53.1% of normal and abnormal pancreas by both radiologists, and 97.6% and 75.5% by at least one radiologist. Most common segmentation errors were made on pancreatic and duodenal borders in both groups, and related to pancreatic tumor including duct dilatation, atrophy, tumor infiltration and collateral vessels.

CONCLUSION

Pancreas DNN segmentation is accurate in a majority of cases, however, minor manual editing may be necessary; particularly in abnormal pancreas.

Anatomical and Biological Considerations to Determine Resectability in Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) remains associated with poor outcomes with a 5-year survival of 12% across all stages of the disease. These poor outcomes are driven by a delay in diagnosis and an early propensity for systemic dissemination of the disease. Recently, aggressive surgical approaches involving complex vascular resections and reconstructions have become more common, thus allowing more locally advanced tumors to be resected. Unfortunately, however, even after the completion of surgery and systemic therapy, approximately 40% of patients experience early recurrence of disease. To determine resectability, many institutions utilize anatomical staging systems based on the presence and extent of vascular involvement of major abdominal vessels around the pancreas. However, these classification systems are based on anatomical considerations only and do not factor in the burden of systemic disease. By integrating the biological criteria, we possibly could avoid futile resections often associated with significant morbidity. Especially patients with anatomically resectable disease who have a heavy burden of radiologically undetected systemic disease most likely do not derive a survival benefit from resection. On the contrary, we could offer complex resections to those who have locally advanced or oligometastatic disease but have favorable systemic biology and are most likely to benefit from resection. This review summarizes the current literature on defining anatomical and biological resectability in patients with pancreatic cancer.

Outcomes after distal pancreatectomy with or without splenectomy for intraductal papillary mucinous neoplasm: international multicentre cohort study

BACKGROUND

International guidelines on intraductal papillary mucinous neoplasm (IPMN) recommend a formal oncological resection including splenectomy when distal pancreatectomy is indicated. This study aimed to compare oncological and surgical outcomes after distal pancreatectomy with or without splenectomy in patients with presumed IPMN.

METHODS

An international, retrospective cohort study was undertaken in 14 high-volume centres from 7 countries including consecutive patients after distal pancreatectomy for IPMN (2005-2019). Patients were divided into spleen-preserving distal pancreatectomy (SPDP) and distal pancreatectomy with splenectomy (DPS). The primary outcome was lymph node metastasis (LNM). Secondary outcomes were overall survival, duration of operation, blood loss, and secondary splenectomy.

RESULTS

Overall, 700 patients were included after distal pancreatectomy for IPMN; 123 underwent SPDP (17.6%) and 577 DPS (82.4%). The rate of malignancy was 29.6% (137 patients) and the overall rate of LNM 6.7% (47 patients). Patients with preoperative suspicion of malignancy had a LNM rate of 17.2% (23 of 134) versus 4.3% (23 of 539) among patients without suspected malignancy (P < 0.001). Overall, SPDP was associated with a shorter operating time (median 180 versus 226 min; P = 0.001), less blood loss (100 versus 336 ml; P = 0.001), and shorter hospital stay (5 versus 8 days; P < 0.001). No significant difference in overall survival was observed between SPDP and DPS for IPMN after correction for prognostic factors (HR 0.50, 95% c.i. 0.22 to 1.18; P = 0.504).

CONCLUSION

This international cohort study found LNM in 6.7% of patients undergoing distal pancreatectomy for IPMN. In patients without preoperative suspicion of malignancy, SPDP seemed oncologically safe and was associated with improved short-term outcomes compared with DPS.

Accurate non-invasive grading of nonfunctional pancreatic neuroendocrine tumors with a CT derived radiomics signature

PURPOSE

The purpose of this study was to develop a radiomics-signature using computed tomography (CT) data for the preoperative prediction of grade of nonfunctional pancreatic neuroendocrine tumors (NF-PNETs).

MATERIALS AND METHODS

A retrospective study was performed on patients undergoing resection for NF-PNETs between 2010 and 2019. A total of 2436 radiomic features were extracted from arterial and venous phases of pancreas-protocol CT examinations. Radiomic features that were associated with final pathologic grade observed in the surgical specimens were subjected to joint mutual information maximization for hierarchical feature selection and the development of the radiomic-signature. Youden-index was used to identify optimal cutoff for determining tumor grade. A random forest prediction model was trained and validated internally. The performance of this tool in predicting tumor grade was compared to that of EUS-FNA sampling that was used as the standard of reference.

RESULTS

A total of 270 patients were included and a fusion radiomic-signature based on 10 selected features was developed using the development cohort (n = 201). There were 149 men and 121 women with a mean age of 59.4 ± 12.3 (standard deviation) years (range: 23.3-85.0 years). Upon internal validation in a new set of 69 patients, a strong discrimination was observed with an area under the curve (AUC) of 0.80 (95% confidence interval [CI]: 0.71-0.90) with corresponding sensitivity and specificity of 87.5% (95% CI: 79.7-95.3) and 73.3% (95% CI: 62.9-83.8) respectively. Of the study population, 143 patients (52.9%) underwent EUS-FNA. Biopsies were non-diagnostic in 26 patients (18.2%) and could not be graded due to insufficient sample in 42 patients (29.4%). In the cohort of 75 patients (52.4%) in whom biopsies were graded the radiomic-signature demonstrated not different AUC as compared to EUS-FNA (AUC: 0.69 vs. 0.67; P = 0.723), however greater sensitivity (i.e., ability to accurately identify G2/3 lesion was observed (80.8% vs. 42.3%; P < 0.001).

CONCLUSION

Non-invasive assessment of tumor grade in patients with PNETs using the proposed radiomic-signature demonstrated high accuracy. Prospective validation and optimization could overcome the commonly experienced diagnostic uncertainty in the assessment of tumor grade in patients with PNETs and could facilitate clinical decision-making.

Recurring Pancreatic Neuroendocrine Tumor: Timing and Pattern of Recurrence and Current Treatment

OBJECTIVE

The objective of this study was to describe the pattern of recurrence, treatments received, as well the oncological outcomes, of pancreatic neuroendocrine tumors (PanNETs) following curative surgery.

BACKGROUND

PanNETs recur in 10% to 15% of cases following surgery. Information on the natural history and management of recurring disease is lacking.

MATERIALS AND METHODS

Patients with PanNET that underwent curative surgery at 4 institutions between 2000 and 2019 were identified. Patients with poorly differentiated tumors, unknown tumor grade and differentiation, hereditary syndromes, unknown margin or R2 status, metastatic, and those that had neoadjuvant treatment or perioperative mortality were excluded. Clinical variables were assessed including first site of recurrence, treatment received, and survival outcomes.

RESULTS

A total of 1402 patients were included: 957 (74%) had grade 1, 322 (25%) had grade 2, and 13 (1%) had grade 3 tumors. Median follow-up was 4.8 years (interquartile range: 2-8.2 years). Cumulative incidence of recurrence at 5 years was 13% (95% CI: 11%-15.2%) for distant disease, 1.4% (95% CI: 0.8%-2.3%) for locoregional recurrence, and 0.8% (95% CI: 0.4%-1.5%) for abdominal nodal recurrence. Patients who recurred had 2.89 increased risk of death (95% CI: 2-4.1) as compared with patients who did not recur. Therapy postrecurrence included: somatostatin analogs in 111 (61.0%), targeted therapies in 48 (26.4%), liver-directed therapies in 61 (33.5%), peptide receptor radionuclide therapy in 30 (16.5%), and surgery in 46 (25.3%) patients. Multiple treatments were used in 103 (57%) cases. After the first recurrence, 5-year overall survival was 74.6% (95% CI: 67.4%-82.5%).

CONCLUSIONS

Recurrence following surgery is infrequent but reduces survival. Most recurrences are distant and managed with multiple therapies. Prospective studies are needed to establish strategies for surveillance and the sequence of treatment to control the disease and prolong survival.

Detecting Somatic Mutations for Well-Differentiated Pancreatic Neuroendocrine Tumors in Endoscopic Ultrasound-Guided Fine Needle Aspiration with Next-Generation Sequencing

BACKGROUND

Pancreatic neuroendocrine tumors (PanNETs) exhibit heterogenous behavior, whereby some small tumors are aggressive with a propensity for metastasis. Detection of somatic mutations associated with aggressive biology may help with patient stratification and surgical decision-making in patients with well-differentiated PanNETs. Using next-generation sequencing (NGS), we investigated the feasibility of detecting somatic mutations in endoscopic ultrasound-guided, fine-needle aspiration (EUS-FNA) specimens and determining the mutational concordance between the EUS-FNA specimens and the primary tumors.

METHODS

Thirty-eight patients with well-differentiated, nonfunctioning PanNETs were obtained from two tertiary referral centers. Patient demographic characteristics and tumor, clinicopathologic features were collected. Tissue from both the EUS-FNA specimen and the primary tumor was extracted from archival tissue blocks. NGS using a panel of ten genes was performed on both samples.

RESULTS

In our series, the median age was 61.1 years. Tumors were predominantly left-sided (60.5%) and unifocal (94.7%). The median tumor size was 2.2 cm. NGS detected somatic mutations in 29% of primary tumors and 36.8% of EUS-FNA specimens. In primary tumors, DAXX/ATRX mutations were predominantly detected (63.6%). In EUS-FNA specimens, MEN1 mutations were predominantly detected (64.3%). Among non-wild-type specimens, mutational concordance was achieved in 31.6% of cases. In 11 patients with a detectable mutation in the primary tumor, a mutation was detected in the EUS-FNA specimen in 45.5% of cases, with a mutational concordance of 54.5%.

CONCLUSIONS

NGS can detect somatic mutations in EUS-FNA specimens of well-differentiated PanNETs. Efforts to improve detection sensitivity and mutational concordance are required to overcome current technical limitations.

Concepts and techniques for revascularization of replaced hepatic arteries in pancreatic head resections

BACKGROUND

The relationship of pancreatic ductal adenocarcinoma (PDAC) to important peripancreatic vasculature dictates resectability. As per the current guidelines, tumors with extensive, unreconstructible venous or arterial involvement are staged as unresectable locally advanced pancreatic cancer (LAPC). The introduction of effective multiagent chemotherapy and development of surgical techniques, have renewed interest in local control of PDAC. High-volume centers have demonstrated safe resection of short-segment encasement of the common hepatic artery. Knowledge of the unique anatomy of the patient's vasculature is important in surgical planning of these complex resections. Hepatic artery anomalies are common and insufficient knowledge can result in iatrogenic vascular injury during surgery.

METHODS AND RESULTS

Here, we discuss different strategies to resect and reconstruct replaced hepatic arteries during pancreatectomy for PDAC to ensure restoration of adequate blood flow to the liver. Strategies include various arterial transpositions, in-situ interposition grafts and the use of extra-anatomic jump grafts.

CONCLUSION

These surgical techniques allow more patients to undergo the only available curative treatment currently available for PDAC. Moreover, these improvements in surgical techniques highlight the shortcoming of current resectability criteria, which rely mainly on local tumor involvement and technical resectability, and disregards tumor biology.

Progression of Site-Specific Recurrence of Pancreatic Cancer and Implications for Treatment

OBJECTIVE

This study aimed to analyze post-recurrence progression in context of recurrence sites and assess implications for post-recurrence treatment.

BACKGROUND

Most patients with resected pancreatic ductal adenocarcinoma (PDAC) recur within two years. Different survival outcomes for location-specific patterns of recurrence are reported, highlighting their prognostic value. However, a lack of understanding of post-recurrence progression and survival remains.

METHODS

This retrospective analysis included surgically treated PDAC patients at the NYU-Langone Health (2010-2021). Sites of recurrence were identified at time of diagnosis and further follow-up. Kaplan-Meier curves, log-rank test, and Cox-regression analyses were applied to assess survival outcomes.

RESULTS

Recurrence occurred in 57.3% (196/342) patients with a median time to recurrence of 11.3 months (95%CI:12.6 to 16.5). First site of recurrence was local in 43.9% patients, liver in 23.5%, peritoneal in 8.7%, lung in 3.6%, while 20.4% had multiple sites of recurrence. Progression to secondary sites was observed in 11.7%. Only lung involvement was associated with significantly longer survival after recurrence compared to other sites (16.9 months vs. 8.49 months, P=0.003). In local recurrence, 21 (33.3%) patients were alive after one year without progression to secondary sites. This was associated with a CA19-9 of <100U/ml at time of primary diagnosis (P=0.039), nodal negative disease (P=0.023), and well-moderate differentiation (P=0.042) compared to patients with progression.

CONCLUSION

Except for lung recurrence, post-recurrence survival after PDAC resection is associated with poor survival. A subset of patients with local-only recurrence do not quickly succumb to systemic spread. This is associated with markers for favorable tumor biology, making them candidates for potential curative re-resections when feasible.

Oncologic resection of pancreatic cancer with isolated liver metastasis: Favorable outcomes in select patients

BACKGROUND

Patients with pancreatic ductal adenocarcinoma (PDAC) and liver metastasis are treated with palliative chemotherapy, whereas similar patients with metastatic colorectal cancer are considered for aggressive surgery.

METHODS

Using an institutional database, PDAC patients undergoing liver resection for isolated metastasis were identified. Their overall survival (OS), treatment factors, and clinicopathological variables associated with survival were also evaluated.

RESULTS

Forty-seven patients underwent curative-intent surgery for metastatic PDAC to the liver between 2000 and 2019. Median OS was 21.9 months from diagnosis. Fourteen patients underwent unplanned resection of radiographically occult liver metastasis during pancreatectomy with median OS of 8.7 months. On the other hand, 29 patients received systemic chemotherapy followed by planned resection; this cohort had the most favorable prognosis following aggressive surgery with median OS being 38.1 months from diagnosis and 24.1 months from surgery. Preoperative chemotherapy (HR = 7.1; p = .002) and moderate to well differentiation of the primary tumor (HR = 3.7; p = .003) were associated with prolonged survival in multivariate analysis, whereas lymph node metastases, response to preoperative therapy, number of liver metastasis, and extent of liver surgery were not.

CONCLUSIONS

In select patients with PDAC and isolated liver metastasis, curative-intent surgery can result in meaningful survival. This aggressive approach seems most beneficial in patients following induction chemotherapy.

Conduits in Vascular Pancreatic Surgery: Analysis of Clinical Outcomes, Operative Techniques, and Graft Performance

OBJECTIVES

We analyze successes and failures of pushing the boundaries in vascular pancreatic surgery to establish safety of conduit reconstructions.

BACKGROUND

Improved systemic control from chemotherapy in pancreatic cancer is increasing the demand for surgical solutions of extensive local vessel involvement, but conduit-specific data are scarce.

METHODS

We identified 63 implanted conduits (41% autologous vessels, 37% allografts, 18% PTFE) in 56 pancreatic resections of highly selected cancer patients between October 2013 and July 2020 from our prospectively maintained database. Assessed parameters were survival, perioperative complications, operative techniques (anatomic and extra-anatomic routes), and conduit patency.

RESULTS

For vascular reconstruction, 25 arterial and 38 venous conduits were utilized during 39 pancreatoduodenectomies, 14 distal pancreatectomies, and 3 total pancreatectomies. The median postoperative survival was 2 years. A Clavien-Dindo grade ≥IIIa complication was apparent in 50% of the patients with a median Comprehensive Complication Index of 29.6. The 90-day mortality in this highly selected cohort was 9%. Causes of mortality were conduit related in 3 patients, late postpancreatectomy hemorrhage in 1 patient, and early liver metastasis in 1 patient. Image-based patency rates of conduits were 66% and 45% at postoperative days 30 and 90, respectively.

CONCLUSIONS

Our perioperative mortality of vascular pancreatic surgery with conduits in the arterial or venous system is 9%. Reconstructions are technically feasible with different anatomic and extra-anatomic strategies, while identifying predictors of early conduit occlusion remains challenging. Optimizing reconstructed arterial and venous hemodynamics in the context of pancreatic malignancy will enable long-term survival in more patients responsive to chemotherapies.

Persistent Circulating Tumor Cells at 1 Year After Oncologic Resection Predict Late Recurrence in Pancreatic Cancer

OBJECTIVE

The aim of the study was to assess the association between persistent circulating tumor cells (CTCs) and subsequent recurrence in patients who were clinically recurrence free ~12 months postoperatively.

BACKGROUND

Circulating tumor cells have been proposed as biomarkers to predict survival in pancreatic cancer. Some patients demonstrate persistent CTCs postoperatively, which could represent minimal residual disease.

METHODS

Patients from previously published prospective circulating tumor cell in pancreatic cancer trial without clinical evidence of recurrence 12 months postoperatively and CTC testing performed 9 to 15 months postoperatively were included. The presence of epithelial and transitional CTCs (trCTCs) was evaluated as predictor of recurrence. Kaplan-Meier curve, log-rank test, and Cox model were used for survival analysis.

RESULTS

Thirty-three of 129 eligible patients (circulating tumor cell in pancreatic cancer trial) were included. The trCTC-positive and negative patients were well balanced in clinicopathologic features. Patients with trCTCs had a recurrence rate per-person-month of 10.3% compared with 3.1% in trCTCs-negative patients with a median time to recurrence of 3.9 versus 27.1 months, respectively. On multivariable analysis, trCTCs positivity was associated with higher risk of late recurrence (hazard ratio: 4.7, 95% CI, 1.2-18.3, P =0.024). Fourteen (42.4%) patients recurred during the second postoperative year. One-year postoperative trCTCs positivity was associated with a higher rate of recurrence during the second year (odds ratio:13.1, 95% CI, 1.6-1953.4, P =0.028, area under curve=0.72). Integrating clinicopathologic features with trCTCs increased the area under curve to 0.80. A majority of trCTCs-positive patients (N=5, 62.5%) had multisite recurrence, followed by local-only (N=2, 25.0%) and liver-only (N=1, 12.5%) recurrence. This was in striking contrast to trCTCs-negative patients, where a majority (N=6, 66.7%) had a local-only recurrence, followed by liver-only (N=2, 22.2%) and multisite (N=1, 11.1%) recurrence.

CONCLUSIONS

In patients deemed to be clinically disease-free 12 months postoperatively, trCTCs positivity is associated with higher rates of subsequent recurrence with distinct patterns of recurrence. CTCs could be used a putative biomarker to guide patient prognostication and management in pancreatic cancer.

A Delay in Adjuvant Therapy Is Associated With Worse Prognosis Only in Patients With Transitional Circulating Tumor Cells After Resection of Pancreatic Ductal Adenocarcinoma

OBJECTIVES

The aim of the study was to assess the association of circulating tumor cells (CTCs) with survival as a biomarker in pancreatic ductal adenocarcinoma (PDAC) within the context of a delay in the initiation of adjuvant therapy.

BACKGROUND

Outcomes in patients with PDAC remain poor and are driven by aggressive systemic disease. Although systemic therapies improve survival in resected patients, factors such as a delay in the initiation of adjuvant therapy are associated with worse outcomes. CTCs have previously been shown to be predictive of survival.

METHODS

A retrospective study was performed on PDAC patients enrolled in the prospective CircuLating tUmor cellS in pancreaTic cancER trial (NCT02974764) on CTC-dynamics at the Johns Hopkins Hospital. CTCs were isolated based on size (isolation by size of epithelial tumor cells; Rarecells) and counted and characterized by subtype using immunofluorescence. The preoperative and postoperative blood samples were used to identify 2 CTC types: epithelial CTCs (eCTCs), expressing pancytokeratin, and transitional CTCs (trCTCs), expressing both pancytokeratin and vimentin. Patients who received adjuvant therapy were compared with those who did not. A delay in the receipt of adjuvant therapy was defined as the initiation of therapy ≥8 weeks after surgical resection. Clinicopathologic features, CTCs characteristics, and outcomes were analyzed.

RESULTS

Of 101 patients included in the study, 43 (42.5%) experienced a delay in initiation and 20 (19.8%) did not receive adjuvant therapy. On multivariable analysis, the presence of trCTCs ( P =0.002) and the absence of adjuvant therapy ( P =0.032) were associated with worse recurrence-free survival (RFS). Postoperative trCTC were associated with poorer RFS, both in patients with a delay in initiation (12.4 vs 17.9 mo, P =0.004) or no administration of adjuvant chemotherapy (3.4 vs NR, P =0.016). However, it was not associated with RFS in patients with timely initiation of adjuvant chemotherapy ( P =0.293).

CONCLUSIONS

Postoperative trCTCs positivity is associated with poorer RFS only in patients who either experience a delay in initiation or no receipt of adjuvant therapy. This study suggests that a delay in the initiation of adjuvant therapy could potentially provide residual systemic disease (trCTCs) a window of opportunity to recover from the surgical insult. Future studies are required to validate these findings and explore the underlying mechanisms involved.

Grading Pancreatic Neuroendocrine Tumors Via Endoscopic Ultrasound-guided Fine Needle Aspiration: A Multi-institutional Study

OBJECTIVES

To identify factors associated with concordance between World Health Organization (WHO) grade on cytological analysis (c-grade) and histopathological analysis (h-grade) of surgical specimen in patients with PanNETs and examine trends in utilization and accuracy of EUS-FNA in preoperatively predicting grade.

BACKGROUND

WHO grading system is prognostic in pancreatic neuroendo-crine tumors (PanNETs). The concordance between c-grade and h-grade is reported to be between 50% and 92%.

METHODS

A multicenter retrospective study was performed on patients undergoing resection for PanNETs at four high-volume centers between 2010 and 2019. Patients with functional or syndrome-associated tumors, and those receiving neoadjuvant therapy were excluded. Factors associated with concordance between c-grade and h-grade and trends of utilization of EUS-FNA were assessed.

RESULTS

Of 869 patients included, 517 (59.5%) underwent EUS-FNA; 452 (87.4%) were diagnostic of PanNETs and WHO-grade was reported for 270 (59.7%) patients. The concordance between c-grade and h-grade was 80.4% with moderate concordance ( Kc = 0.52, 95% CI: 0.41-0.63). Significantly higher rates of concordance were observed in patients with smaller tumors (<2 vs. ≥2cm, 81.1% vs. 60.4%, P = 0.005). Highest concordance (98.1%) was observed in patients with small tumors undergoing assessment between 2015-2019 with a near-perfect concordance ( Kc = 0.88, 95% CI: 0.61-1.00). An increase in the utilization of EUS-FNA (56.1% to 64.1%) was observed over the last 2 decades ( P = 0.017) and WHO-grade was more frequently reported (44.2% vs. 77.6%, P < 0.001). However, concordance between c-grade and h-grade did not change significantly (P = 0.118).

CONCLUSION

Recently, a trend towards increasing utilization and improved diagnostic accuracy of EUS-FNA has been observed in PanNETs. Concordance between c-grade and h-grade is associated with tumor size with near-perfect agreement when assessing PanNETs <2cm in size.

Tailoring Adjuvant Chemotherapy to Biologic Response Following Neoadjuvant Chemotherapy Impacts Overall Survival in Pancreatic Cancer

BACKGROUND

The role of postoperative chemotherapy in patients with resected pancreatic cancer who receive neoadjuvant treatment is unknown. Clinicians use changes in CA19-9 and histopathologic scores to assess treatment response. We sought to investigate if CA19-9 normalization in response to NAT can help guide the need for postoperative treatment.

METHODS

Patients with elevated baseline CA19-9 (CA19-9 > 37U/mL) who received NAT followed by surgery between 2011 and 2019 were retrospectively reviewed. Treatment response was determined by CA19-9 normalization following NAT and histopathologic scoring. The role of postoperative chemotherapy was analyzed in light of CA19-9 normalization and histopathologic response.

RESULTS

We identified and included 345 patients. Following NAT, CA19-9 normalization was observed in 125 patients (36.2%). CA19-9 normalization was associated with a favorable histopathologic response (41.6% vs 23.2%, p < 0.001) and a lower ypT (p < 0.001) and ypN stage (p = 0.003). Receipt of adjuvant chemotherapy was associated with improved overall survival in patients in whom CA19-9 did not normalize following NAT (26.8 vs 16.4 months, p = 0.008). In patients who received 5FU-based NAT and in whom CA19-9 did not normalize, receipt of 5FU-based adjuvant chemotherapy was associated with improved OS (p = 0.014).

CONCLUSION

CA19-9 normalization in response to NAT was associated with favorable outcomes and can serve as a biomarker for treatment response. In patients where CA19-9 did not normalize, receipt of postoperative chemotherapy was associated with improved OS. These patients also benefited from additional 5FU-based postoperative chemotherapy following 5FU-based NAT.

Surgical Decision-Making in Pancreatic Ductal Adenocarcinoma: Modeling Prognosis Following Pancreatectomy in the Era of Induction and Neoadjuvant Chemotherapy

OBJECTIVE

To develop a predictive model of oncologic outcomes for patients with pancreatic ductal adenocarcinoma (PDAC) undergoing resection after neoadjuvant or induction chemotherapy use.

BACKGROUND

Early recurrence following surgical resection for PDAC is common. The use of neoadjuvant chemotherapy prior to resection may increase the likelihood of long-term systemic disease control. Accurately characterizing an individual's likely oncologic outcome in the perioperative setting remains challenging.

METHODS

Data from patients with PDAC who received chemotherapy prior to pancreatectomy at a single high-volume institution between 2007 and 2018 were captured in a prospectively collected database. Core clinicopathologic data were reviewed for accuracy and survival data were abstracted from the electronic medical record and national databases. Cox-proportional regressions were used to model outcomes and develop an interactive prognostic tool for clinical decision-making.

RESULTS

A total of 581 patients were included with a median overall survival (OS) and recurrence-free survival (RFS) of 29.5 (26.5-32.5) and 16.6 (15.8-17.5) months, respectively. Multivariable analysis demonstrates OS and RFS were associated with type of chemotherapeutic used andthe number of chemotherapy cycles received preoperatively. Additional factors contributing to survival models included: tumor grade, histopathologic response to therapy, nodal status, and administration of adjuvant chemotherapy. The models were validated using an iterative bootstrap method and with randomized cohort splitting. The models were well calibrated with concordance indices of 0.68 and 0.65 for the final OS and RFS models, respectively.

CONCLUSION

We developed an intuitive and dynamic decision-making tool that can be useful in estimating OS, RFS, and location-specific disease recurrence rates. This prognostic tool may add value to patient care in discussing the benefits associated with surgical resection for PDAC.

A novel tool to predict nodal metastasis in small pancreatic neuroendocrine tumors: A multicenter study

BACKGROUND

Nonfunctional pancreatic neuroendocrine tumors display a wide range of biological behavior, and nodal disease is associated with metastatic disease and poorer survival. The aim of this study was to develop a tool to predict nodal disease in patients with small (≤2 cm) nonfunctional pancreatic neuroendocrine tumors.

METHODS

A multicenter retrospective study was performed on patients undergoing resection for small nonfunctional pancreatic neuroendocrine tumors. Patients with genetic syndromes, metastatic disease at diagnosis, neoadjuvant therapy, or positive resection margin were excluded. Factors associated with nodal disease were identified to develop a predictive model. Internal validation was performed using bootstrap with 1,000 resamples.

RESULTS

Nodal disease was observed in 39 (11.1%) of the 353 patients included. Presence of nodal disease was significantly associated with lower 5-year disease-free survival (71.6% vs 96.2%, P < .001). Two predictors were strongly associated with nodal disease: G2 grade (odds ratio: 3.51, 95% confidence interval: 1.71-7.22, P = .001) and tumor size (per mm increase, odds ratio: 1.14, 95% confidence interval: 1.03-1.25, P = .009). Adequate discrimination was observed with an area under the curve of 0.71 (95% confidence interval: 0.63-0.80). Based on risk distribution, 3 risk groups of nodal disease were identified; low (<5%), intermediate (≥5% to <20%), and high (≥20%) risk. The observed mean risk of nodal disease was 3.7% in the low-risk patients, 9.6% in the intermediate-risk patients, and 30.4% in the high-risk patients (P < .001). The 10-year disease-free survival in the low, intermediate, and high-risk groups was 100%, 88.8%, and 50.1%, respectively.

CONCLUSION

Our model using tumor grade and size can predict nodal disease in small nonfunctional pancreatic neuroendocrine tumors. Integration of this tool into clinical practice could help guide management of these patients.

Classification of pancreatic cystic neoplasms using radiomic feature analysis is equivalent to an experienced academic radiologist: a step toward computer-augmented diagnostics for radiologists

PURPOSE

A wide array of benign and malignant lesions of the pancreas can be cystic and these cystic lesions can have overlapping imaging appearances. The purpose of this study is to compare the diagnostic accuracy of a radiomics-based pancreatic cyst classifier to an experienced academic radiologist.

METHODS

In this IRB-approved retrospective single-institution study, patients with surgically resected pancreatic cysts who underwent preoperative abdominal CT from 2003 to 2016 were identified. Pancreatic cyst(s) and background pancreas were manually segmented, and 488 radiomics features were extracted. Random forest classification based on radiomics features, age, and gender was evaluated with fourfold cross-validation. An academic radiologist blinded to the final pathologic diagnosis reviewed each case and provided the most likely diagnosis.

RESULTS

214 patients were included (64 intraductal papillary mucinous neoplasms, 33 mucinous cystic neoplasms, 60 serous cystadenomas, 24 solid pseudopapillary neoplasms, and 33 cystic neuroendocrine tumors). The radiomics-based machine learning approach showed AUC of 0.940 in pancreatic cyst classification, compared with AUC of 0.895 for the radiologist.

CONCLUSION

Radiomics-based machine learning achieved equivalent performance as an experienced academic radiologist in the classification of pancreatic cysts. The high diagnostic accuracy can potentially maximize the efficiency of healthcare utilization by maximizing detection of high-risk lesions.

Predictors, Patterns, and Timing of Recurrence Provide Insight into the Disease Biology of Invasive Carcinomas Arising in Association with Intraductal Papillary Mucinous Neoplasms

OBJECTIVES

To identify predictors, patterns, and timing of recurrence after resection of invasive carcinomas arising in association with an IPMN.

BACKGROUND

Postoperative management of an invasive carcinoma arising in association with an intraductal papillary mucinous neoplasm (IPMN), a biologically distinct entity from PanIN-derived pancreatic ductal adenocarcinoma (PDAC), remains largely based on guidelines for PanIN-derived PDAC. To minimize treatment failure and inform disease-specific management, cancer recurrence must be better characterized.

METHODS

Patients were identified from a prospectively maintained registry between 1996 and 2018. Predictors of recurrence were evaluated by employing Cox regression models to determine risk-adjusted hazard ratios (HR) with 95% confidence intervals (95%CI). The patterns and timing of recurrence were recognized and compared utilizing a log-rank test, respectively.

RESULTS

Of the 213 patients included, 92 (43.2%) recurred with a median RFS of 23.7 months (16.7-30.7). The predominant pattern of recurrence included any systemic (65.2%). The median time to local recurrence was longer than systemic (21.6 versus 11.4 months, p = 0.05). Poor differentiation [HR: 3.01, 95%CI (1.06-8.61)] and nodal disease [N1, HR: 2.23, 95%CI (1.12-4.60); and N2, HR: 5.67 95%CI (2.93-10.99)] emerged as independent predictors of systemic recurrence. For local-specific recurrences, poor differentiation [HR: 3.73, 95%CI (1.04-13.45)] and an R1 margin [high-grade dysplasia or invasive carcinoma; HR: 2.66, 95%CI (1.14-6.21)] emerged as independent predictors.

CONCLUSIONS

The predominant pattern of recurrence after resection of invasive carcinomas arising in association with IPMNs is systemic, and occurs earlier than local recurrence. Poor differentiation and nodal disease are associated with systemic recurrence while poor differentiation and an R1 margin are associated with local recurrence. Future studies should investigate the role of systemic (chemotherapy) versus local (radiation) therapies and surveillance strategies in a personalized manner.

Cinematic Rendering: Novel Tool for Improving Pancreatic Cancer Surgical Planning

Pancreatic ductal adenocarcinoma is the third-leading cause of all cancer-related deaths in the US. While 20% of patients have resectable disease at diagnosis, improved control of systemic disease using effective chemotherapeutic regimens allows for aggressive operations involving complex vascular resection and reconstruction. A pancreas protocol computed tomography (PPCT) is the gold standard imaging modality in determining local resectability (degree of tumor-vessel involvement), however, it is limited by the inter-operator variability. While post-processing-3D-rendering helps, it does not allow for real-time dynamic assessment of resectability. A recent development in post-process-rendering called cinematic rendering (CR) overcomes this by utilizing advanced light modeling to generate photorealistic 3D images with enhanced details. Cinematic rendering allows for nuanced visualization of areas of interest. Our preliminary experience, as one of the first centers to incorporate the routine use of CR, has proven very useful in surgical planning. For local determination of resectability, vascular mapping allows for accurate assessment of major arteries and the portovenous system. For the portovenous anatomy it assists in determining the optimal surgical approach (extent of resection, appropriate technique for reconstruction, and need for mesocaval shunting). For arterial anatomy, vessel encasement either represents dissectible involvement via periadventitial dissection or true vessel invasion that is unresectable. CR could potentially provide superior ability than traditional PPCT to discern between the two. Additionally, CR allows for better 3D visualization of arterial anatomic variants which, if not appreciated preoperatively, increases risk of intraoperative ischemia and postoperative complications. Lastly, CR could help avoid unnecessary surgery by enhanced identification of occult metastatic disease that is metastatic disease that is otherwise not appreciated on a standard PPCT.

Long-term Outcomes of Parenchyma-sparing and Oncologic Resections in Patients With Nonfunctional Pancreatic Neuroendocrine Tumors <3 cm in a Large Multicenter Cohort

INTRODUCTION

The role of parenchyma-sparing resections (PSR) and lymph node dissection in small (<3 cm) nonfunctional pancreatic neuroendocrine tumors (PNET) is unlikely to be studied in a prospective randomized clinical trial. By combining data from 4 high-volume pancreatic centers we compared postoperative and long-term outcomes of patients who underwent PSR with patients who underwent oncologic resections.

METHODS

Retrospective review of prospectively collected clinicopathologic data of patients who underwent pancreatectomy between 2000 and 2021 was collected from 4 high-volume institutions. PSR and lymph node-sparing resections (enucleation and central pancreatectomy) were compared to those who underwent oncologic resections with lymphadenectomy (pancreaticoduodenectomy, distal pancreatectomy). Statistical testing was performed using χ 2 test and t test, survival estimates with Kaplan-Meier method and multivariate analysis using Cox proportional hazard model.

RESULTS

Of 810 patients with small sporadic nonfunctional PNETs, 121 (14.9%) had enucleations, 100 (12.3%) had central pancreatectomies, and 589 (72.7%) patients underwent oncologic resections. The median age was 59 years and 48.2% were female with a median tumor size of 2.5 cm. After case-control matching for tumor size, 221 patients were selected in each group. Patients with PSR were more likely to undergo minimally invasive operations (32.6% vs 13.6%, P <0.001), had less intraoperative blood loss (358 vs 511 ml, P <0.001) and had shorter operative times (180 vs 330 minutes, P <0.001) than patients undergoing oncologic resections. While the mean number of lymph nodes harvested was lower for PSR (n=1.4 vs n=9.9, P <0.001), the mean number of positive lymph nodes was equivalent to oncologic resections (n=1.1 vs n=0.9, P =0.808). Although the rate of all postoperative complications was similar for PSR and oncologic resections (38.5% vs 48.2%, P =0.090), it was higher for central pancreatectomies (38.5% vs 56.6%, P =0.003). Long-term median disease-free survival (190.5 vs 195.2 months, P =0.506) and overall survival (197.9 vs 192.6 months, P =0.372) were comparable. Of the 810 patients 136 (16.7%) had no lymph nodes resected. These patients experienced less blood loss, shorter operations ( P <0.001), and lower postoperative complication rates as compared to patients who had lymphadenectomies (39.7% vs 56.9%, P =0.008). Median disease-free survival (197.1 vs 191.9 months, P =0.837) and overall survival (200 vs 195.1 months, P =0.827) were similar for patients with no lymph nodes resected and patients with negative lymph nodes (N0) after lymphadenectomy.

CONCLUSION

In small <3 cm nonfunctional PNETs, PSRs and lymph node-sparing resections are associated with lower blood loss, shorter operative times, and lower complication rates when compared to oncologic resections, and have similar long-term oncologic outcomes.

Implications of Perineural Invasion on Disease Recurrence and Survival After Pancreatectomy for Pancreatic Head Ductal Adenocarcinoma

OBJECTIVE

To describe PNI and to evaluate its impact on disease-free (DFS) and overall survival (OS) in patients with resected pancreatic ductal adenocarcinoma (PDAC).

SUMMARY OF BACKGROUND DATA

Although PNI is a prognostic factor for survival in many GI cancers, there is limited knowledge regarding its impact on tumor recurrence, especially in ''early stage disease'' (PDAC ≤20 mm, R0/ N0 PDAC).

METHODS

This multicenter retrospective study included patients undergoing PDAC resection between 2009 and 2014. The association of PNI with DFS and OS was analyzed using Cox proportional-hazards models.

RESULTS

PNI was found in 87% of 778 patients included in the study, with lower rates in PDAC ≤20 mm (78.7%) and in R0/N0 tumors (70.6%). PNI rate did not differ between patients who underwent neoadjuvant therapy and upfront surgery (88% vs 84%, P = 0.08). Although not significant at multivariate analysis ( P = 0.07), patients with PNI had worse DFS at univariate analysis (median DFS: 20 vs 15 months, P < 0.01). PNI was the only independent predictor of DFS in R0/N0 tumors (hazard ratio [HR]: 2.2) and in PDAC ≤ 20 mm (HR: 1.8). PNI was an independent predictor of OS in the entire cohort (27 vs 50 months, P = 0.01), together with G3 tumors, pN1 status, carbohydrate antigen (CA) 19.9 >37 and pain.

CONCLUSIONS

PNI represents a major determinant of tumor recurrence and patients' survival in pancreatic cancer. The role of PNI is particularly relevant in early stages, supporting the hypothesis that invasion of nerves by cancer cells has a driving role in pancreatic cancer progression.

Association of Matrix Metalloproteinase 7 Expression With Pathologic Response After Neoadjuvant Treatment in Patients With Resected Pancreatic Ductal Adenocarcinoma

Importance

The use of neoadjuvant therapy (NAT) in resectable pancreatic ductal adenocarcinoma (PDAC) remains controversial. A favorable pathologic response (complete or marked tumor regression) to NAT is associated with better outcomes in patients with resected PDAC. The role of NAT for early systemic control compared with immediate surgical resection for PDAC is under investigation. In the era of precision medicine, biomarkers for patient selection and prediction of therapy response are crucial.

Objective

To evaluate the use of assessment for protein expression on fine-needle aspiration (FNA) biopsy specimens in predicting pathologic response to NAT in treatment-naive patients.

Design, Setting, and Participants

This was a single-institution prognostic study from a high-volume center for pancreatic cancer. All specimens were obtained between January 1, 2009, and December 31, 2018, with a median (SE) follow-up of 20.2 (1.4) months. Analysis of the data was performed from October 1, 2019, to April 30, 2021. Targeted RNA sequencing of frozen FNA biopsy specimens from a discovery cohort of 23 patients was performed to identify genes with aberrant expression that was associated with patients' pathologic response to NAT. Immunohistochemical staining was performed on an additional 80 FNA biopsy specimens to assess expression of matrix metalloproteinase 7 (MMP-7) and its association with pathologic response. Receiver operating characteristic curves for prediction of favorable pathologic response were determined.

Results

In the discovery cohort (12 [52.1%] male; 3 [13.0%] Black and 20 [86.9%] White), RNA sequencing showed that lower MMP-7 expression was associated with favorable pathologic response (College of American Pathologists system scores of 0 [complete response] and 1 [marked response]). In the validation cohort (40 [50.0%] female; 9 [11.3%] Black and 71 [88.7%] White), patients with negative MMP-7 expression were significantly more likely to have a favorable pathologic response (odds ratio, 21.25; 95% CI, 6.19-72.95; P = .001). Receiver operating characteristic curves for prediction of favorable pathologic response from multivariable Cox proportional hazards regression modeling showed that MMP-7 expression increased the area under the curve from 0.726 to 0.906 (P < .001) even after stratifying by resectability status. The positive predictive value and negative predictive value of MMP-7 protein expression on FNA biopsy specimens in predicting unfavorable pathologic response (scores of 2 [partial response] or 3 [poor or no response]) were 88.2% and 73.9%, respectively.

Conclusions and Relevance

Assessment of MMP-7 expression on FNA biopsy specimens at the time of diagnosis may help identify patients who would benefit the most from NAT.

RAD51B Harbors Germline Mutations Associated With Pancreatic Ductal Adenocarcinoma

PURPOSE

Genetic alterations in many components of the homologous recombination, DNA damage response, and repair (HR-DDR) pathway are involved in the hereditary cancer syndromes, including familial pancreatic cancer. HR-DDR genes beyond BRCA1, BRCA2, ATM, and PALB2 may also mutate and confer the HR-DDR deficiency in pancreatic ductal adenocarcinoma (PDAC).

METHODS

We conducted a study to examine the genetic alterations using a companion diagnostic 15-gene HR-DDR panel in PDACs. HR-DDR gene mutations were identified and characterized by whole-exome sequencing and whole-genome sequencing. Different HR-DDR gene mutations are associated with variable homologous recombination deficiency (HRD) scores.

RESULTS

Eight of 50 PDACs with at least one HR-DDR gene mutation were identified. One tumor with BRCA2 mutations is associated with a high HRD score. However, another tumor with a CHEK2 mutation is associated with a zero HRD score. Notably, four of eight PDACs in this study harbor a RAD51B gene mutation. All four RAD51B gene mutations were germline mutations. However, currently, RAD51B is not the gene panel for germline tests.

CONCLUSION

The finding in this study thus supports including RAD51B in the germline test of HR-DDR pathway genes.

The Impact of the COVID-19 Pandemic on Multidisciplinary Clinics: A High-Volume Pancreatic Cancer Center Experience

The unprecedented impact of the Sars-CoV-2 pandemic (COVID-19) has strained the healthcare system worldwide. The impact is even more profound on diseases requiring timely complex multidisciplinary care such as pancreatic cancer. Multidisciplinary care teams have been affected significantly in multiple ways as healthcare teams collectively acclimate to significant space limitations and shortages of personnel and supplies. As a result, many patients are now receiving suboptimal remote imaging for diagnosis, staging, and surgical planning for pancreatic cancer. In addition, the lack of face-to-face interactions between the physician and patient and between multidisciplinary teams has challenged patient safety, research investigations, and house staff education. In this study, we discuss how the COVID-19 pandemic has transformed our high-volume pancreatic multidisciplinary clinic, the unique challenges faced, as well as the potential benefits that have arisen out of this situation. We also reflect on its implications for the future during and beyond the pandemic as we anticipate a hybrid model that includes a component of virtual multidisciplinary clinics as a means to provide accessible world-class healthcare for patients who require complex oncologic management.

Anatomic Criteria Determine Resectability in Locally Advanced Pancreatic Cancer

BACKGROUND

The introduction of multi-agent chemotherapy and radiation therapy has facilitated potential resection with curative intent in selected locally advanced pancreatic cancer (LAPC) patients with excellent outcomes. Nevertheless, there remains a remarkable lack of consensus on the management of LAPC. We sought to describe the outcomes of patients with LAPC and objectively define the multidisciplinary selection process for operative exploration based on anatomical factors.

METHODS

Consecutive patients with LAPC were evaluated for pancreatic surgery in the multidisciplinary clinic of a high-volume institution, between 2013 and 2018. Prospective stratification (LAPC-1, LAPC-2, and LAPC-3), based on the involvement of regional anatomical structures, was performed at the time of presentation prior to the initiation of treatment. Resection rates and patient outcomes were evaluated and correlated with the initial anatomic stratification system.

RESULTS

Overall, 415 patients with LAPC were included in the study, of whom 84 (20%) were successfully resected, with a median overall survival of 35.3 months. The likelihood of operative exploration was associated with the pretreatment anatomic LAPC score, with a resection rate of 49% in patients classified as LAPC-1, 32% in LAPC-2, and 11% in LAPC-3 (p < 0.001). Resected patients with improvement of the LAPC score at the time of exploration had significantly longer median overall survival compared with those with no change or progression of LAPC score (60.7 vs. 29.8 months, p = 0.006).

CONCLUSIONS

Selected patients with LAPC can undergo curative-intent surgery with excellent outcomes. The proposed Johns Hopkins anatomic LAPC score provides an objective system to anticipate the probability of eventual surgical resection after induction therapy.

Reliable Detection of Somatic Mutations for Pancreatic Cancer in Endoscopic Ultrasonography-Guided Fine Needle Aspirates with Next-Generation Sequencing: Implications from a Prospective Cohort Study

BACKGROUND OR PURPOSE

Pancreatic ductal adenocarcinoma (PDAC) is commonly diagnosed by endoscopic ultrasound-guided fine needle aspiration (EUS-FNA). However, the diagnostic adequacy of EUS-FNA is often limited by low cellularity leading to inconclusive results. We aimed to investigate the feasibility and added utility of targeted next-generation sequencing (NGS) on PDAC EUS-FNAs.

METHODS

EUS-FNAs were prospectively performed on 59 patients with suspected PDAC (2014-2017) at a high-volume center. FNAs were analyzed for the presence of somatic mutations using NGS to supplement cytopathologic evaluations and were compared to surgical specimens and circulating tumor DNA (ctDNA).

RESULTS

Fifty-nine patients with suspected PDAC were evaluated, and 52 were diagnosed with PDAC on EUS-FNA. Four of the remaining seven patients had inconclusive EUS-FNAs and were ultimately diagnosed with PDAC after surgical resection. Of these 56 cases of PDAC, 48 (85.7%) and 18 (32.1%) harbored a KRAS and/or TP53 mutation on FNA NGS, respectively. Particularly, in the four inconclusive FNA PDAC diagnoses (false negatives), half harbored KRAS mutations on FNA. No KRAS/TP53 mutation was found in remaining three non-PDAC cases. All EUS-FNA detected KRAS mutations were detected in 16 patients that underwent primary tumor NGS (100% concordance), while 75% KRAS concordance was found between FNA and ctDNA NGS.

CONCLUSION

Targeted NGS can reliably detect KRAS mutations from EUS-FNA samples and exhibits high KRAS mutational concordance with primary tumor and ctDNA. This suggests targeted NGS of EUS-FNA samples may enable preoperative ctDNA prognostication using digital droplet PCR and supplement diagnoses in patients with inconclusive EUS-FNA.

Favorable tumor biology in locally advanced pancreatic cancer-beyond CA19-9

Patients with pancreatic ductal adenocarcinoma (PDAC) are frequently staged as unresectable locally advanced pancreatic cancer (LAPC) at the time of diagnosis. Recently, the administration of multi-agent induction chemotherapy has resulted in treatment response in up to 60% of these patients rendering their tumors technically resectable. Operative strategies have evolved to allow for successful oncologic resection of LAPC. These technically complex procedures involving vascular resections and reconstructions are now being performed with increasing safety at high-volume centers. However, even after induction therapy and successful resection, disease recurrence sometimes occurs early on, limiting the benefit of resecting the local tumor. Therefore, selection of surgical candidates should factor in each patient's tumor biology which could result in accurate treatment guidance to improve patient outcomes while avoiding overtreatment. Well-informed patient selection is critical to improve outcomes in LAPC. Multidisciplinary teams have to determine the appropriate care for LAPC patients at the time of reevaluation after administration of induction chemotherapy. At this point the concept of favorable vs. unfavorable tumor biology becomes highly relevant and having access to biomarkers that are predictive of tumor behavior are of paramount importance. Currently, CA19-9 remains the only clinically utilized biomarker for PDAC, however, its use is limited by factors discussed in this review. While CA19-9 holds value in patient assessment, additional biomarkers are required that could supplement and improve the current ability to classify tumor biology and predict behavior in individual patients. Recent investigations on the use of circulating tumor DNA (ctDNA) and circulating tumor cells (CTCs) using liquid biopsies, as well as patient-derived organoids to characterize tumor biology have shown promise in achieving precise tumor biology-based patient stratification. Serial assessment of these biomarkers throughout therapy could supplement or even replace the anatomic criteria for resectability in the future.

Comprehensive Analysis of Somatic Mutations in Driver Genes of Resected Pancreatic Ductal Adenocarcinoma Reveals KRAS G12D and Mutant TP53 Combination as an Independent Predictor of Clinical Outcome

BACKGROUND

Prognosis in pancreatic ductal adenocarcinoma (PDAC) remains poor despite improved systemic therapies and surgical techniques. The identification of biomarkers to advance insight in tumor biology and achieve better individualized prognostication could help improve outcomes. Our aim was to elucidate the prognostic role of the four main driver mutations (KRAS, TP53, SMAD4, CDKN2A) and their combinations in resected PDAC.

PATIENTS AND METHODS

A retrospective analysis was conducted utilizing the cBioPortal database and National Cancer Institute's Cancer Genomic Atlas (TCGA) on patients in whom next-generation sequencing was performed on upfront resected PDAC from 2012 to 2020. Multivariable Cox regression was implemented to elucidate risk-adjusted predictors of overall (OS) and recurrence-free survival (RFS). Results were validated employing a Johns Hopkins Hospital (JHH) cohort.'

RESULTS

In the discovery cohort (n = 587), increased number of mutated driver genes was associated with worse OS (p = 0.047). Specifically, patients with mutations in ≥ 2 driver genes had worse OS than ≤ 1 mutated gene (18.2 versus 32.3 months, p = 0.033). Co-occurrence of mutant (mt)KRAS p.G12D with mtTP53 (median OS, 25.9 months) conferred better prognosis than co-occurrence of other mtKRAS variants (p.G12V/R/other) with mtTP53 (median OS, 16.9 months, p = 0.038). The findings were validated using a JHH cohort. Multivariable risk-adjustment found co-occurrence of mtKRAS p.G12D with mtTP53 to be an independent predictor of beneficial OS and RFS [HR (95% CI): 0.18 (0.03-0.81) and 0.31 (0.11-0.89) respectively].

CONCLUSION

In chemo-naïve resected PDAC, combinations of mutations in the four driver genes are associated with prognosis. In patients with combined mtKRAS and mtTP53, KRAS p.G12D variant confers a better OS and RFS.

Postoperative biliary anastomotic strictures after pancreaticoduodenectomy

BACKGROUND

Biliary anastomotic stricture (BAS) is an uncommon complication of pancreaticoduodenectomy (PD). As PDs are performed more frequently, BAS may become a more common pathologic entity requiring clinical engagement. The aim of this study was to report the incidence of BAS in the modern era of pancreatic surgery and identify risk factors associated with it.

METHODS

Patients undergoing PD at the Johns Hopkins Hospital between 2007 and 2016 were identified using an institutional registry and clinicopathological features were analyzed to identify risk factors associated with BAS.

RESULTS

Of 2125 patients identified, 103 (4.9%) developed BAS. Factors independently associated with BAS included laparoscopic approach (HR:2.83,95%CI:1.35-5.92, p = 0.006), postoperative pancreatic fistula (HR:2.45,95%CI:1.56-4.16,p < 0.001), postoperative bile leak (BL) (HR:5.26,95%CI:2.45-11.28,p < 0.001), and administration of adjuvant radiation therapy (HR:6.01,95%CI:3.19-11.34,p < 0.001). Malignant pathology was associated with lower rates of BAS (HR:0.52,95%CI:0.30-0.92, p = 0.025). BL was associated with higher rates of early-BAS (HR:16.49,95%CI:3.28-82.94, p = 0.001) while use of Vicryl suture for biliary enteric anastomosis was associated with lower rates of early-BAS (HR:0.20,95%CI:0.05-0.93, p = 0.041).

CONCLUSION

Approximately 5% of patients undergoing PD experience BAS. Multiple factors are associated with the development and timing of BAS.

Technical progress in robotic pancreatoduodenectomy: TRIANGLE and periadventitial dissection for retropancreatic nerve plexus resection

PURPOSE

The resection of retropancreatic nerve plexuses for pancreatic head cancer became standard of care during open pancreatoduodenectomy to minimize local recurrences. Since more surgical centers are progressing on the learning curve, robotically-assisted pancreatoduodenectomy is now increasingly performed with decreasing anatomic exclusion criteria. To achieve comparable and favorable oncologic outcomes, advanced surgical techniques should be transferred and implemented when performing robotic resections.

METHODS

The nomenclature and anatomic principles of retropancreatic nerve plexuses and three different levels of dissections are utilized based on established definitions.

RESULTS

The en bloc dissection in the "TRIANGLE" area (triangular-shaped retropancreatic space enclosed by the common hepatic artery, superior mesenteric artery, and superior mesenteric vein/portal vein) and the periadventitial dissection of arteries for non-tunica media-invading tumors were executed robotically. Both can be utilized to achieve a radical dorsal and medial margin. Video recordings are provided to illustrate varying TRIANGLE dissections.

CONCLUSION

To accomplish oncologic non-inferiority, established principles from open pancreatic resections can be incorporated precisely and safely, overcoming the lack of haptic feedback while exploiting the technological advantages of the robotically-assisted platform.

Impact of Postoperative Glycemic Control on Postoperative Morbidity in Patients Undergoing Open Pancreaticoduodenectomy

OBJECTIVE

To evaluate the impact of postoperative glycemic control on postoperative morbidity in patients undergoing a pancreaticoduodenectomy.

METHODS

A retrospective study was performed on patients at The Johns Hopkins Hospital between April 2015 and April 2016. Data were collected on postoperative insulin regimens, blood glucose, rates of hyperglycemia and hypoglycemia, and postoperative complications and were evaluated.

RESULTS

Out of 244 patients, 114 (46.7%) experienced at least 1 hyperglycemic (>180 mg/dL) episode and 16 (6.6%) experienced at least 1 hypoglycemic episode (<70 mg/dL) during the first postoperative 24 hours. Early postoperative hyperglycemia (>180 mg/dL) was associated with a significantly higher rate of surgical site infections (15.7% vs 7%; P = 0.031). Late postoperative hyperglycemia (>180 mg/dL) was associated with a significantly higher rate of fistulas (4.3% vs 14.6%; P = 0.021).

CONCLUSIONS

Early hyperglycemia (>180 mg/dL) is associated with a higher risk of surgical site infections while late hyperglycemia is associated with a higher risk of fistulas. Intensive glucose control (<150 mg/dL) was not demonstrated to decrease the risk of postoperative complications. Similar to other critically ill populations, targeting a glucose goal of <180 mg/dL may be an appropriate target to reduce morbidity without increasing the risk of hypoglycemia.

Progression vs Cyst Stability of Branch-Duct Intraductal Papillary Mucinous Neoplasms After Observation and Surgery

Importance

The progression of intraductal papillary mucinous neoplasms (IPMNs) of the pancreas to malignant disease is still poorly understood. Observational and surgical series have failed to provide comprehensive information.

Objective

To identify dynamic variables associated with the development of malignant neoplasms by combining pathological features with data from preoperative repeated observations.

Design, Setting, and Participants

The Crossover Observational Multicentric Study included a retrospective cohort of patients with branch-duct IPMNs (BD IPMNs) enrolled in a surveillance program from January 1, 2000, to December 31, 2019. Patients were enrolled from 5 referral centers: the Pancreas Institute, Verona, Italy; Seoul National University Hospital, Seoul, South Korea; Singapore General Hospital, Singapore; Johns Hopkins School of Medicine, Baltimore, Maryland; and University of Texas MD Anderson Cancer Center, Houston. Patients underwent a minimum of 12 months of preoperative surveillance (median, 37 [interquartile range (IQR), 20-68] months).

Main Outcomes and Measures

Dynamic variables associated with malignant disease were explored to estimate the presence of high-grade dysplasia (HGD) and invasive cancer at final pathological examination.

Results

A total of 292 patients were included in the analysis (137 women [46.9%] and 155 men [53.1%]; median age, 64 [IQR, 56-71] years). During surveillance, 27 patients (9.2%) developed a worrisome feature after 5 years, and 46 of 276 (16.7%) developed high-risk stigmata (HRS). At final pathological evaluation, 107 patients (36.6%) had HGD or invasive cancer, and 16 (5.5%) had IPMNs with concomitant pancreatic ductal adenocarcinoma. Rates of HGD and invasive cancer at pathological evaluation significantly differed between those without worrisome features and those developing HRS from a previous worrisome feature (9 [27.3%] vs 13 [61.9%]; P < .001). Developing an additional worrisome feature during surveillance (odds ratio [OR], 3.24 [95% CI, 1.38-7.60]; P = .007) or an HRS from a baseline worrisome feature (OR, 2.87 [95% CI, 1.01-8.17]; P = .048) was associated with HGD at final pathological evaluation. Among HRS, development of jaundice on a low-risk cyst was independently associated with invasive cancer (OR, 16.04 [95% CI, 2.94-87.40]; P = .001).

Conclusions and Relevance

These findings suggest that in BD IPMNs under surveillance, harboring a stable worrisome feature carries the lowest risk of malignant disease. Development of additional worrisome features or HRS is associated with the presence of HGD, whereas the occurrence of jaundice is associated with invasive cancer.

Autoimmune Pancreatitis: A Critical Analysis of the Surgical Experience in an Era of Modern Diagnostics

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.

Role of Lymph Node Resection and Histopathological Evaluation in Accurate Staging of Nonfunctional Pancreatic Neuroendocrine Tumors: How Many Are Enough?

BACKGROUND

Nodal involvement has been identified as one of the strongest prognostic factors in patients with nonfunctional pancreatic neuroendocrine tumors (NF-PanNETs). Sufficient lymphadenectomy and evaluation is vital for accurate staging. The purpose of this study was to identify the optimal number of examined lymph nodes (ELN) required for accurate staging.

METHODS

The SEER database was used to identify patients with resected NF-PanNETs between 2004 and 2014. The distributions of positive lymph nodes (PLN) ratio and total lymph nodes were used to develop a mathematical model. The sensitivity of detecting nodal disease at each cutoff of ELN was estimated and used to identify the optimal cutoff for ELN.

RESULTS

A total of 1098 patients were included in the study of which 391 patients (35.6%) had nodal disease. The median ELN was 12 (interquartile range [IQR]: 7-19.5), and the median PLN was 2 (IQR: 1-4) for patients with nodal disease. With an increase in ELN, the sensitivity of detecting nodal disease increased from 12.0% (ELN: 1) to 92.2% (ELN: 20), plateauing at 20 ELN (< 1% increase in sensitivity with an additional ELN). This sensitivity increase pattern was similar in subgroup analyses with different T stages.

CONCLUSIONS

The sensitivity of detecting nodal disease in patients with NF-PanNETs increases with an increase in the number of ELN. Cutoffs for adequate nodal assessment were defined for all T stages. Utilization of these cutoffs in clinical settings will help with patient prognostication and management.

Challenges of the current precision medicine approach for pancreatic cancer: A single institution experience between 2013 and 2017

Recent research on genomic profiling of pancreatic ductal adenocarcinoma (PDAC) has identified many potentially actionable alterations. However, the feasibility of using genomic profiling to guide routine clinical decision making for PDAC patients remains unclear. We retrospectively reviewed PDAC patients between October 2013 and December 2017, who underwent treatment at the Johns Hopkins Hospital and had clinical tumor next-generation sequencing (NGS) through commercial resources. Ninety-two patients with 93 tumors tested were included. Forty-eight (52%) patients had potentially curative surgeries. The median time from the tissue available to the NGS testing ordered was 229 days (interquartile range 62-415). A total of three (3%) patients had matched targeted therapies based on genomic profiling results. Genomic profiling guided personalized treatment for PDAC patients is feasible, but the percentage of patients who receive targeted therapy is low. The main challenges are ordering NGS testing early in the clinical course of the disease and the limited evidence of using a targeted approach in these patients. A real-time department level genomic testing ordering system in combination with an evidence-based flagging system for potentially actionable alterations could help address these shortcomings.

Duodenal, ampullary, and pancreatic neuroendocrine tumors: Oncologic outcomes are driven by tumor biology and tissue of origin

BACKGROUND

Periampullary neuroendocrine tumors (NETs) arise from the duodenum, ampulla, and periampullary pancreas. Duodenal and ampullary NETs are rare and may have distinct biologic behavior from pancreatic NETs (P-NETs). We examined the outcomes of these entities.

METHODS

An institutional database was queried for patients undergoing resection for pancreatic head, duodenal, or ampullary NETs from 2000 to 2018. Patients with MEN1 syndrome or follow up less than 12 months were excluded.

RESULTS

Three hundred and ten patients were identified. Tumor locations were ampulla (n = 15), duodenum (n = 35) and pancreas (n = 260). Median follow-up and recurrence-free survival (RFS) were 60.9 (interquartile range [IQR]: 34.8-99.3) and 171.7 (IQR: 84.0-NR) months. Clinicopathologic data and survival outcomes were similar for duodenal and ampullary NETs (RFS: p = .347 and overall survival [OS]: p = .246) and were combined into an intestinal subtype (IS) group. There were no differences in OS or RFS when comparing IS-NET and P-NET. On multivariate analysis, tissue of origin was not associated with risk of recurrence. The current American Joint Committee on Cancer staging guidelines, which account for origin tissue, were predictive of outcomes for all subtypes.

CONCLUSION

Tissue of origin does not appear to impact long-term outcomes when comparing IS-NETs and P-NETs. The AJCC staging system offers good discriminatory capacity in the context of the tissue type.

An Aggressive Approach to Locally Confined Pancreatic Cancer: Defining Surgical and Oncologic Outcomes Unique to Pancreatectomy with Celiac Axis Resection (DP-CAR)

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 was supplemented with dedicated chart review and outreach for long-term oncologic outcomes.

Results:

Fifty-four patients underwent DP-CAR between 2008–2018. The median age was 62.7 years. 98% received induction chemotherapy. Arterial reconstruction was performed in 17% and concomitant visceral resection in 30%. 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 ninety-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.

Periadventitial dissection of the superior mesenteric artery for locally advanced pancreatic cancer: Surgical planning with the "halo sign" and "string sign"

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.

Perioperative CT angiography assessment of locally advanced distal pancreatic carcinoma to evaluate feasibility of the modified Appleby procedure

PURPOSE

To study the perioperative CT angiography (CTA) findings of modified Appleby procedure candidates for the surgical feasibility in patients with locally advanced distal pancreatic cancer (LAPC) and to assess CTA performance.

MATERIALS AND METHODS

This retrospective study evaluated CTA of patients with distal LAPC who underwent modified Appleby procedure between March 2004 and October 2017. Preoperative CT scans performed within up to three months prior to the surgery and postoperative scans, at least one of which was within one month of surgery, were reviewed. Data was collected reporting tumor size, relation to vessels, changes from neoadjuvant chemoradiation, modifications to the surgery and complications. The CTA findings were correlated with operative notes and surgical pathology. Statistical analysis was performed using binary classification method to evaluate CTA performance.

RESULTS

Consecutive 20 patients underwent modified Appleby procedure in the study period. In 18/20 patients who received neoadjuvant chemoradiation, mean pancreatic mass size significantly reduced from 4.58 + 1.17 cm to 3.55 + 0.84 cm (p = 0.002). The celiac axis (CA) was encased in all, whereas none of the patients had encasement of the superior mesenteric artery (SMA) or involvement of gastroduodenal artery (GDA). The CTA had 88.89% sensitivity, 100% specificity, and 90% accuracy for evaluating the arterial involvement.

CONCLUSION

Distal LAPC patients, in particular those who have significant size reduction after neoadjuvant chemoradiation, with encasement of CA and without encasement of SMA and GDA can undergo a technically successful modified Appleby procedure. CTA offers accurate and valuable perioperative assessment of the surgical candidates.

Mesoportal bypass, interposition graft, and mesocaval shunt: Surgical strategies to overcome superior mesenteric vein involvement in pancreatic cancer

BACKGROUND

In pancreatic cancer, extensive tumor involvement of the mesenteric venous system poses formidable challenges to operative resection. Such involvement can result from cavernous collateral veins leading to increased intraoperative blood loss or long-segment vascular defects of not only just the superior mesenteric vein but also even jejunal/ileal branches. Strategies to facilitate margin-free resection and safe vascular reconstruction in pancreatic surgery are important, particularly because systemic control of the tumor is improving with multi-agent chemotherapy regimens.

METHODS

We describe a systematic, multidisciplinary assessment for patients with pancreatic cancer that involves the superior mesenteric vein, as well as the preoperative planning of those undergoing operative resection. In addition, detailed descriptions of operative approaches and technical strategies, which evolved with increasing experience at a high-volume center, are presented.

RESULTS

For the preoperative evaluation of tumor-free, vascular locations for potential reconstruction and collateralization, computed tomographic imaging with high-resolution of vascular structures (used with 3-dimensional or cinematic rendering) allows a precise calibration of radiographic data with intraoperative findings. From an operative perspective, we identified 5 potential strategies to consider for resection: collateral preservation, mesoportal bypass (preresection), mesoportal interposition graft (postresection), mesocaval shunt, and various combinations of these strategies. Many of these techniques use interposition grafts, making it essential to assess autologous veins (preferred conduit for reconstruction) or to prepare cryopreserved vascular allografts (an alternative conduit, which must be thawed and should be matched for size and blood type).

CONCLUSION

Herein we share operative strategies to overcome involvement of the superior mesenteric vein in pancreatic cancer. Improvements in preoperative planning and operative technique can address common barriers to resection with curative intent.