Survival after pancreaticoduodenectomy is not improved by extending resections to achieve negative margins

Clinical impact of intraoperative pancreatic transection margin analysis and additional resection during pancreaticoduodenectomy for pancreatic ductal adenocarcinoma

BACKGROUND

The prognostic impact of additional resection based on intraoperative frozen section analysis (FSA) of the pancreatic transection margin in patients with pancreatic ductal adenocarcinoma (PDAC) is controversial. The purpose of this study was to evaluate the prognosis based on the results of the first FSA of the pancreatic transection margin (1st FSA) and the clinical significance of additional resection.

METHODS

Patients who underwent pancreaticoduodenectomy for PDAC from 2000 to 2020 at a single center were included. Patients were divided into 3 groups based on the 1stFSA. Survival and prognostic factors were analyzed according to the 1stFSA.

RESULTS

A total of 311 patients were included in this study. The 1stFSA was negative in 272 patients (1stFSA-R0) and positive in 39 patients [carcinoma in situ (1stFSA-CIS), 21 patients; invasive carcinoma (1stFSA-IC), 18 patients]. Additional resections were performed on 37 patients [1stFSA-CIS, 20 patients; 1stFSA-IC, 17 patients], and R0 resection was achieved in 34 patients intraoperatively. Comparing median survival time to 1stFSA-R0 (36.4 months), 1stFSA-CIS was comparable (27.8 months, p = 0.276), although 1stFSA-IC was significantly worse (18.8 months, p = 0.001). On multivariate analysis, 1stFSA-IC was an independent prognostic factor (hazard ratio 2.68, 95 % confidence interval 1.16-6.17, p = 0.020).

CONCLUSIONS

1stFSA-CIS and 1stFSA-R0 had similar OS, implying that additional resection may be acceptable for 1stFSA-CIS. 1stFSA-IC was still an independent prognostic factor based on additional resection, and the prognostic significance of additional resection is uncertain for 1stFSA-IC.

To Revise or Not Revise? Isolated Margin Positivity in Localized Pancreatic Ductal Adenocarcinoma

BACKGROUND

The study determined the proportion of patients with pancreatic adenocarcinoma (PDAC) who had margin-positive disease and no other adverse pathologic findings (APF) using institutional and administrative datasets.

METHODS

Patients with clinical stage I or II PDAC in the National Cancer Database (NCDB 2010-2020) and those who underwent pancreatectomy at the authors' institution (2010-2021) were identified. Isolated margin positivity (IMP) was defined as a positive surgical margin with no APF (negative nodes, no lymphovascular/perineural invasion).

RESULTS

The study included 225 patients from the authors' institution and 23,598 patients from the NCDB. The margin-positive rates were 21.8% and 20.3%, and the IMP rates were 0.4% and 0.5%, respectively. In the institutional cohort, 68.4% of the patients had recurrence, and most of the patients (65.6%) had distant recurrences. The median recurrence-free survival (RFS) was 63.3 months for no APF, not reached for IMP, 14.8 months for negative margins & 1 APF, 20.3 months for positive margins & 2 APFs, and 12.9 months with all APF positive. The patients in the NCDB with IMP had a lower median OS than the patients with no APF (20.5 vs 390 months), but a higher median OS than those with margin positivity plus 1 APF (20.5 vs 18.0 months) or all those with APF positivity (20.5 vs 15.4 months). Based on institutional rates of IMP, any margin positivity, neck margin positivity (NMP), and no APF, the fraction of patients who might benefit from neck margin revision was 1 in 100,000, and those likely to benefit from any margin revision was 1 in 18,500. In the NCDB, those estimated to derive potential benefit from margin revision was 1 in 25,000.

CONCLUSIONS

Isolated margin positivity in resected PDAC is rare, and most patients experience distant recurrence. Revision of IMP appears unlikely to confer benefit to most patients.

Impact of Surgical Margin Status on Survival and Recurrence After Pancreaticoduodenectomy for Distal Cholangiocarcinoma: Is Microscopic Residual Tumor (R1) Associated with Higher Rates of Local Recurrence?

BACKGROUND

Patients undergoing macroscopically curative resection for distal cholangiocarcinoma (DCC) have high recurrence rates and poor prognoses. This study aimed to investigate the impact of surgical margin status on survival and recurrence after resection of DCC, specifically focusing on microscopic residual tumor (R1) and its relationship to local recurrence.

PATIENTS AND METHODS

This was a retrospective analysis of patients who had undergone pancreaticoduodenectomy (PD) for DCC between 2005 and 2021. Surgical margin was classified as R0, R1cis (positive bile duct margin with carcinoma in situ), and R1inv (positive bile duct margin with an invasive subepithelial component and/or positive radial margin).

RESULTS

In total, 29 of 133 patients (21.8%) had R1cis and 23 (17.3%) R1inv. The 5-year overall survival (OS) for R0 (55.7%) did not differ significantly from that for R1cis/R1inv (47.4%/33.6%, respectively). The 5-year recurrence-free survival (RFS) for R0 was significantly longer than that for R1inv (50.1% vs. 17.4%, p = 0.003), whereas RFS did not differ significantly between those with R0 and R1cis. R1cis/R1inv status was not an independent predictor of OS and RFS in multivariate analysis. Cumulative incidence of isolated distant recurrence was significantly higher for R1cis/R1inv than for R0 (p = 0.0343/p = 0.0226, respectively), whereas surgical margin status was not significantly associated with rates of local or local plus distant recurrence.

CONCLUSIONS

Surgical margin status does not significantly impact OS and RFS in patients undergoing PD for DCC following precise preoperative imaging evaluation. Additionally, R1 status is significantly linked to higher isolated distant recurrence rather than local recurrence, highlighting the importance of multidisciplinary therapy.

A comparative analysis of robotic versus open pancreaticoduodenectomy in octogenarians

Old age is a predictor of increased morbidity following pancreatic operations. This study was undertaken to compare the peri-operative variables between robotic and 'open' pancreaticoduodenectomy, in octogenarians (≥ 80 years of age). Since 2012, with IRB approval, we retrospectively followed 69 patients, who underwent robotic (n = 42) and 'open' (n = 27) pancreaticoduodenectomy. Statistical analysis was performed using chi-square test and Student's t test. Data are presented as median(mean ± SD), and significance accepted with 95% probability. Patients who underwent the robotic approach had a greater Charlson Comorbidity Index [6 (6 ± 1.6) vs 5 (5 ± 1.0), (p = 0.01)] and previous abdominal operations [n = 24 (57%) vs n = 9 (33%), (p = 0.04)]. The robotic approach led to longer operative time [426 (434 ± 95.8) vs 240 (254 ± 71.1) minutes, (p < 0.0001)], decreased blood loss [200 (291 ± 289.2) vs 426 (434 ± 95.8) mL (p = 0.008)], and decreased intraoperative blood transfusions (p < 0.05). Patients who underwent robotic pancreaticoduodenectomy had comparable and at times superior outcomes, consistent with the literature regarding robotic and 'open' pancreaticoduodenectomy. This study indicates that robotic pancreaticoduodenectomy continues to offer same benefits for patients of advanced age and demonstrates age should not be a preclusion to robotic operations.

Vein Wall Invasion Is a More Reliable Predictor of Oncological Outcomes than Vein-Related Margins after Pancreaticoduodenectomy for Early Stages of Pancreatic Ductal Adenocarcinoma

Pancreaticoduodenectomy (PD) with vein resection is the only potentially curative option for patients with pancreatic ductal adenocarcinoma (PDAC) with venous involvement. The aim of our study was to assess the oncological prognostic significance of the different variables of venous involvement in patients undergoing PD for resectable and borderline-resectable with venous-only involvement (BR-V) PDAC. We performed a retrospective analysis of prospectively acquired data over a 10-year period. Of the 372 patients included, 105 (28%) required vein resection and vein wall involvement was identified in 37% of those. A multivariable analysis failed to identify the vein-related resection margins as independent predictors for OS, DFS or LR. Vein wall tumour involvement was an independent predictor of OS (risk x1.7-2) and DFS (risk x1.9-2.2) in all models, while it replaced overall surgical margin positivity as the only parameter independently predicting LR during an analysis of separate resection margins (risk x2.4). Vein wall tumour invasion may be a more reliable predictor of oncological outcomes compared to traditionally reported parameters. Future studies should focus on possible pre-operative investigations that could identify these cases and management pathways that could yield a survival benefit, such as the use of neoadjuvant treatments.

Utility of intraoperative pathology consultations of whipple resection specimens and their impact on final margin status

The resection margin status is a significant surgical prognostic factor for the long-term outcomes of patients undergoing pancreaticoduodenectomy (Whipple procedure). As a result, surgeons frequently rely on intraoperative consults (IOCs) involving frozen sections to evaluate margin clearance during these resections. Nevertheless, the impact of this practice on final margin status and long-term outcomes remains a topic of debate. This study aimed to assess the impact of IOCs on the clearance rate of resection margins following Whipple procedure and distal pancreatectomy. A retrospective database review of all patients who underwent Whipple procedure or distal pancreatectomy at our institution between 2018 and 2020 was performed to evaluate the utility of IOCs by gastrointestinal surgeons and its correlation with final postoperative surgical margin status. A significant variation in the frequency of IOC requests for margins among surgeons was noted. However, the use of frozen section analysis for intraoperative margin assessment was not significantly associated with the clearance rate of final post-operative margins. More frequent use of IOC did not result in higher final margin clearance rate, an important prognostic factor following Whipple procedure.

Evaluation of local recurrence after pancreaticoduodenectomy for borderline resectable pancreatic head cancer with neoadjuvant chemotherapy: Can the resection level change after chemotherapy?

BACKGROUND

Neoadjuvant treatment has significant survival benefits for patients with pancreatic cancer. However, local recurrence remains a serious issue, even after neoadjuvant treatment. This study investigated local recurrence after pancreaticoduodenectomy and determined the optimal resection level after neoadjuvant treatment.

METHODS

This retrospective study analyzed consecutive patients who underwent pancreaticoduodenectomy for borderline resectable pancreatic cancer after 4 cycles of neoadjuvant treatment-gemcitabine plus nab-paclitaxel between April 2015 and March 2020. Patients with borderline resectable-artery pancreatic cancer were classified according to the dissection level around the artery: level 3 group, hemi-, or whole circumferential arterial nerve plexus was dissected; and level 2 group, the nerve plexus was preserved.

RESULTS

Fifty-six patients with borderline resectable-artery pancreatic cancer underwent pancreaticoduodenectomy after neoadjuvant treatment (level 3 group, n = 40; level 2 group, n = 16). The resection level in the level 2 group was changed based on post-neoadjuvant treatment computed tomography images or intraoperative frozen section diagnosis. The overall and local recurrence rates were significantly higher in the level 2 group than in the level 3 group (overall recurrence, 93.8% vs 70.0%; P = .037) (local recurrence, 50.0% vs 5.0%; P < .001). Ten patients experienced local recurrence, of which 8 belonged to the level 2 group. Among them, 4 patients were confirmed as cancer-negative by surgical margin analysis or intraoperative frozen section diagnosis but experienced recurrence around the arteries.

CONCLUSION

For treating borderline resectable-artery pancreatic cancer, changing the resection level based on post-neoadjuvant treatment computed tomography images increased the risk of local recurrence. All patients with borderline resectable-artery should undergo level 3 dissection, regardless of the response to neoadjuvant treatment.

Intraoperative Pancreatic Neck Margin Assessment During Pancreaticoduodenectomy for Pancreatic Adenocarcinoma in the Era of Neoadjuvant Therapy: A Multi-institutional Analysis from the Central Pancreatic Consortium

BACKGROUND

Data regarding the survival impact of converting frozen-section (FS):R1 pancreatic neck margins to permanent section (PS):R0 by additional resection (i.e., converted-R0) during upfront pancreaticoduodenectomy for pancreatic ductal adenocarcinoma (PDAC) are conflicting. The impact of neoadjuvant therapy on this practice and its relationship with overall survival (OS) is incompletely understood.

METHODS

We reviewed PDAC patients (80% borderline resectable/locally advanced [BR/LA]) undergoing pancreaticoduodenectomy after neoadjuvant therapy at seven, academic, high-volume centers (2010-2018). Multivariable models examined the association of PS:R0, PS:R1, and converted-R0 margins with OS.

RESULTS

Of 272 patients receiving at least 2 (median 4) cycles of neoadjuvant chemotherapy (71% mFOLFIRINOX or gemcitabine/nab-paclitaxel) and undergoing pancreaticoduodenectomy with intraoperative frozen-section assessment of the transected pancreatic neck margin, PS:R0 (n = 220, 80.9%) was observed in a majority of patients; 18 patients (6.6%) had converted-R0 margins following additional resection, whereas 34 patients (12.5%) had persistently positive PS:R1 margins. At a median follow-up of 42 months, PS:R0 resection was associated with improved OS compared with either converted-R0 or PS:R1 resection (median 25 vs. 14 vs. 16 months, respectively; p = 0.023), with no survival difference between the converted-R0 and PS:R1 groups (p = 0.9). On Cox regression, SMA margin positivity (hazard ratio 2.2, p = 0.012), but not neck margin positivity (hazard ratio 1.2, p = 0.65), was associated with worse OS.

CONCLUSIONS

In this multi-institutional cohort of predominantly BR/LA PDAC patients undergoing pancreaticoduodenectomy following modern neoadjuvant therapy, pursuing a negative neck margin intraoperatively if the initial margin is positive does not appear to be associated with improved survival.

Impact of the aberrant right hepatic artery on local recurrence of pancreatic ductal adenocarcinoma after pancreaticoduodenectomy

BACKGROUND

The influence and risk associated with an aberrant right hepatic artery, a common anatomical variation, during pancreatoduodenectomy for pancreatic ductal adenocarcinoma has not been fully investigated. The present study analyzed the impact of an aberrant right hepatic artery on local recurrence after pancreatoduodenectomy for pancreatic ductal adenocarcinoma.

METHODS

A total of 169 patients with pancreatic ductal adenocarcinoma who underwent pancreatoduodenectomy at 2 separate Japanese medical institutions were retrospectively analyzed.

RESULTS

Thirty of 169 patients (17.7%) presented with an aberrant right hepatic artery. The incidence of local recurrence was higher in the aberrant right hepatic artery group than in the normal right hepatic artery group (43.3 vs 21.5%, P = .017). The local recurrence-free survival was significantly poorer in the aberrant right hepatic artery group than in the normal right hepatic artery group (P = .011). A multivariate analysis found that the aberrant right hepatic artery was an independent risk factor for local recurrence (hazard ratio: 3.74, P = .017). In the aberrant right hepatic artery group, more frequent local recurrence was observed in patients with tumors situated ≤10 mm from the aberrant right hepatic artery root. However, local recurrence was not observed in 2 out of 3 patients with tumors ≤10 mm from the aberrant right hepatic artery root who underwent pancreatoduodenectomy with combined resection of the aberrant right hepatic artery.

CONCLUSION

The presence of an aberrant right hepatic artery in patients undergoing pancreatoduodenectomy for pancreatic ductal adenocarcinoma may be associated with an increased risk of postoperative local recurrence. Combined resection of the aberrant right hepatic artery may reduce local recurrence, especially for tumors near the root of the aberrant right hepatic artery.

Insight of pancreatic cancer: recommendations for improving its therapeutic efficacy in the next decade

Pancreatic cancer is one of the most malignant digestive system tumors. The effectiveness of pancreatic cancer treatment is still dismal, and the 5-year survival rate is only about 10%. Further improving the diagnosis and treatment of pancreatic cancer is the top priority of oncology research and clinical practice. Based on the existing clinical and scientific research experience, the review provides insight into the hotspots and future directions for pancreatic cancer, which focuses on early detection, early diagnosis, molecular typing and precise treatment, new drug development and regimen combination, immunotherapy, database development, model establishment, surgical technology and strategy change, as well as innovation of traditional Chinese medicine and breakthrough of treatment concept.

Landmark Series: Importance of Pancreatic Resection Margins

An important goal of cancer surgery is to achieve negative surgical margins and remove all disease completely. For pancreatic neoplasms, microscopic margins may remain positive despite gross removal of the palpable mass, and surgeons must then consider extending resection, even to the point of completion pancreatectomy, an option that renders the patient with significant adverse effects related to exocrine and endocrine insufficiency. Counterintuitively, extending resection to ensure clear margins may not improve patient outcome. Furthermore, the goal of improving survival by extending the resection may not be achieved, as an initial positive margin may indicate more aggressive underlying tumor biology. There is a growing body of literature on this topic, and this landmark series review will examine the key publications that guide our management for resection of pancreatic ductal adenocarcinoma, intraductal papillary mucinous neoplasms, and pancreatic neuroendocrine tumors.

Adjuvant Treatment in Pancreatic Cancer: Shaping the Future of the Curative Setting

Pancreatic ductal adenocarcinoma (PDAC) is a lethal disease even in the early stages, despite progresses in surgical and pharmacological treatment in recent years. High potential for metastases is the main cause of therapeutic failure in localized disease, highlighting the current limited knowledge of underlying pathological processes. However, nowadays research is focusing on the search for personalized approaches also in the adjuvant setting for PDAC, by implementing the use of biomarkers and investigating new therapeutic targets. In this context, the aim of this narrative review is to summarize the current treatment scenario and new potential therapeutic approaches in early stage PDAC, from both a preclinical and clinical point of view. Additionally, the review examines the role of target therapies in localized PDAC and the influence of neoadjuvant treatments on survival outcomes.

Clinical impact of preoperative tumour contact with superior mesenteric-portal vein in patients with resectable pancreatic head cancer

INTRODUCTION

The NCCN classification of resectability in pancreatic head cancer does not consider preoperative radiological tumour ≤ 180° contact with portal vein/superior mesenteric vein (PV/SMV) as a negative prognostic feature. The aim of this study is to evaluate whether this factor is associated with higher rate of incomplete resection and poorer survival.

METHODS

All patients considered for pancreatic resection between 2012 and 2017 at two Spanish referral centres were included. Patients with borderline and locally advanced pancreatic ductal adenocarcinoma (PDAC) according to NCCN classification were excluded. Preoperative CT scans were reviewed by dedicated radiologists to identify radiologic tumour contact with PV/SMV.

RESULTS

Out of 302, 71 patients were finally included in this study. Twenty-two (31%) patients showed tumour-PV/SMV contact (group 1) and 49 (69%) did not show any contact (group 2). Patients in group 1 showed a statistically significantly higher rate of R1 and R1-direct margins compared with group 2 (95 vs 28% and 77 vs 10%) and lower median survival (24 vs 41 months, p = 0.02). Preoperative contact with PV/SMV, lymph node metastases, R1-direct margin and NO adjuvant chemotherapy were significantly associated with disease-specific survival at multivariate analysis.

CONCLUSION

Preoperative radiological tumour contact with PV/SMV in patients with NCCN resectable PDAC is associated with high rate of pathologic positive margins following surgery and poorer survival.

Indications to total pancreatectomy for positive neck margin after partial pancreatectomy: a review of a slippery ground

The extension of a partial pancreatectomy up to total pancreatectomy because of positive neck margin examined at intraoperative frozen section (IFS) analysis is an accepted procedure in modern pancreatic surgery with good accuracy. The goal of this practice is to improve the rate of radical (R0) resection in malignant tumors, mainly pancreatic ductal adenocarcinoma (PDAC), and to completely resect pre-invasive neoplasms such as intraductal papillary mucinous neoplasms (IPMNs). In the setting of IPMNs there is a consensus for pancreatic re-resection when high-grade dysplasia and invasive cancer are present at the neck margin. The presence of denudation is another indication for further resection in IPMNs. The role of IFS analysis in the management of pancreatic cancer is more debated. The presence of a positive intraoperative transection margin can be considered the surrogate of a biologically aggressive disease associated with a poorer prognosis. There are conflicting data regarding possible advantages of pancreatic re-resection up to total pancreatectomy, and the lack of randomized trials comparing different strategies does not offer a definitive answer. The goal of this review is to provide an up-to-date overview of the role IFS analysis of pancreatic margin and of pancreatic re-resection up to total pancreatectomy considering different pancreatic tumors.

Reconsideration of the Appropriate Dissection Range Based on Japanese Anatomical Classification for Resectable Pancreatic Head Cancer in the Era of Multimodal Treatment

Patients with resectable pancreatic cancer are considered to already have micro-distant metastasis, because most of the recurrence patterns postoperatively are distant metastases. Multimodal treatment dramatically improves prognosis; thus, micro-distant metastasis is considered to be controlled by chemotherapy. The survival benefit of "regional lymph node dissection" for pancreatic head cancer remains unclear. We reviewed the literature that could be helpful in determining the appropriate resection range. Regional lymph nodes with no suspected metastases on preoperative imaging may become areas treated with preoperative and postoperative adjuvant chemotherapy. Many studies have reported that the R0 resection rate is associated with prognosis. Thus, "dissection to achieve R0 resection" is required. The recent development of high-quality computed tomography has made it possible to evaluate the extent of cancer infiltration. Therefore, it is possible to simulate the dissection range to achieve R0 resection preoperatively. However, it is often difficult to distinguish between areas of inflammatory changes and cancer infiltration during resection. Even if the "dissection to achieve R0 resection" range is simulated based on the computed tomography evaluation, it is difficult to identify the range intraoperatively. It is necessary to be aware of anatomical landmarks to determine the appropriate dissection range during surgery.

Irreversible Electroporation (IRE) Combined With Chemotherapy Increases Survival in Locally Advanced Pancreatic Cancer (LAPC)

OBJECTIVES

Locally advanced pancreatic cancer (LAPC) is found in about 40% of patients with pancreatic cancer. Irreversible electroporation (IRE) is a nonthermal ablative technique that provides an alternative in patients with LAPC and can be safely combined with chemotherapy.

MATERIALS AND METHODS

From 2015 until October of 2019, we performed laparotomic IRE in a total of 40 patients with stage III LAPC. The median age of these patients was 65.2 years (range: 46 to 81 y), and the median tumor size was 3.8 cm (range: 2 to 5.2 cm). 33 of 40 patients were treated preoperatively with FOLFIRINOX or nab-paclitaxel plus gemcitabine and in case of disease control, IRE was performed, whereas in 7 patients, IRE was performed without previous chemotherapy.

RESULTS

All patients were treated successfully with IRE as the tumor evaluation showed no disease progression after the completion of induction chemotherapy. No IRE-related deaths occurred. Two major grade III complications were reported: pancreatic fistula grade A in 8 patients and 3 patients diagnosed with delayed gastric emptying. Up to October 31, 2019, the median overall survival (OS) of all patients was 24.2 months (range: 6 to 36 mo), and the median progression-free survival was 10.3 months (range: 3 to 24 mo). After the completion of IRE, 30 patients (75%) continued with adjuvant chemotherapy. Fifteen patients (37%) have >24 months OS and 3 patients (8%) have reached 36 months OS and are still alive.

CONCLUSION

The combination of chemotherapy with IRE, which is a safe and effective procedure, may result in a survival benefit for patients with LAPC.

Contemporary Reappraisal of Intraoperative Neck Margin Assessment During Pancreaticoduodenectomy for Pancreatic Ductal Adenocarcinoma: A Review

Importance

Although margin-negative (R0) resection is the gold standard for surgical management of localized pancreatic ductal adenocarcinoma (PDAC), the question of how to manage the patient with a microscopically positive intraoperative neck margin (IONM) during pancreaticoduodenectomy remains controversial.

Observations

In the absence of randomized clinical trials, we critically evaluated high-quality retrospective studies examining the oncologic utility of re-resecting positive IONMs during pancreaticoduodenectomy for PDAC (2000-2019). Several studies have concluded that additional pancreatic resection to achieve an R0 margin in IONM-positive cases does not influence survival. The largest is a multi-institutional study of 1399 patients undergoing pancreaticoduodenectomy, which demonstrated that in comparison with patients undergoing R0 resection (n = 1196; median survival, 21 months), those with either final R1 resections (n = 131) or undergoing margin conversion from IONM-positive to R0 resection on permanent section (n = 72) demonstrated similar median survival times (13.7 and 11.9 months, respectively). Conversely, recent reports suggest that the conversion of IONM to R0 resection with additional resection or even total pancreatectomy may be associated with improved survival. The discordance between these conflicting studies could be explained in part by the influence of biologic and physiologic selection on the association of IONM re-resection and survival. Since most studies did not include patients receiving modern combination chemotherapy regimens, the intersection between margin status, tumor biology, and chemoresponsiveness remains unclear. Furthermore, there are no dedicated data to guide surgical management in IONM-positive pancreaticoduodenectomy for patients receiving neoadjuvant chemotherapy.

Conclusions and Relevance

Although data regarding the oncologic utility of additional resection to achieve a tumor-free margin following initial IONM positivity during pancreaticoduodenectomy for PDAC are conflicting, they suggest that IONM positivity may be a surrogate for biologic aggressiveness that is unlikely to be mitigated by the extent of surgical resection. The complex relationship between margin status and chemoresponsiveness warrants exploration in studies including patients receiving increasingly effective neoadjuvant chemotherapy.

Survival after Margin-Positive Resection in the Era of Modern Chemotherapy for Pancreatic Cancer: Do Patients Still Benefit?

BACKGROUND

R0 resection for pancreatic cancer is considered standard of care, but is not always achieved. This study looks at R1/R2 resection outcomes compared with chemotherapy alone. Our hypothesis is that patients with margin-positive disease have better outcomes than those receiving chemotherapy alone.

STUDY DESIGN

Stage II pancreatic cancer patients who underwent R1/R2 surgery with/without neoadjuvant chemotherapy, from the National Cancer Database (NCDB) 2010 to 2017 were identified and compared with similar staged patients who received chemotherapy alone. The surgical group was then analyzed by subset based on receipt of chemotherapy: upfront surgery (+/- adjuvant therapy) and neoadjuvant therapy followed by surgery (+/- adjuvant therapy).

RESULTS

There were 11,699 Stage II pancreatic cancer patients included, 9,521 (81.4%) of whom were treated with chemotherapy alone, 15.7% (n = 1,836) had upfront surgery, and 2.9% (n = 342) had neoadjuvant therapy with surgery. R1/R2 neoadjuvant patients had the best overall survival at a mean of 19.75 months (95% CI 17.91, 22.28) compared with the upfront surgery group (17.77 months, 95% CI 15.64, 19.55) and the chemotherapy alone group (10.12 months, 95% CI 8.97, 11.50) (hazard ratio [HR] 0.46 upfront surgery and 0.32 neoadjuvant group, respectively, p < 0.0001). Even with R2 resection, survival was better in surgical patients compared with patients who underwent chemotherapy only (15.76 mo vs 10.22 mo, p = 0.06). Patients with R1/R2 resections had improved survival if they received neoadjuvant/adjuvant chemotherapy, though the survival rates were significantly lower than those with standard R0 resections (n = 16,129).

CONCLUSIONS

R1 resection has benefit over chemotherapy alone in pancreatic cancer. Pancreatic cancer patients who are left with microscopic R1 disease have better survival than without surgery, particularly in the setting of neoadjuvant therapy.

Cost Analysis of Pancreaticoduodenectomy at a High-Volume Robotic Hepatopancreaticobiliary Surgery Program

BACKGROUND

The robotic approach to pancreaticoduodenectomy is thought by many to be associated with increased financial burden for hospitals. We undertook this study to analyze and compare the cost of "open" pancreaticoduodenectomy with that associated with the application of the robotic surgical system to pancreaticoduodenectomy in our hepatobiliary program.

STUDY DESIGN

With IRB approval, all patients undergoing pancreaticoduodenectomy at our institution, from August 2012 to November 2019, were prospectively followed. Cost, including total, variable, fixed-direct, fixed-indirect, and profitability for robotic and "open" pancreaticoduodenectomy were analyzed and compared. Data are presented as median (mean ± SD).

RESULTS

There were 386 patients who underwent pancreaticoduodenectomy; 205 patients underwent robotic pancreaticoduodenectomy and 181 underwent "open" pancreaticoduodenectomy. Costs are presented as mean ± SD. Overall, the cost of care for robotic pancreaticoduodenectomy was $31,389 ($36,611 ± $20,545.40) vs $23,132 ($31,323 ± $28,885.50) for "open" pancreaticoduodenectomy (p = 0.04); total variable cost was $20,355 ($22,747 ± $11,127.60) vs $11,680 ($16,032 ± $14,817.20) (p = 0.01), total fixed direct cost was $1,999 ($2,330 ± $1,363.10) vs $2,073 ($2,983 ± $3,209.00) (p = 0.01), and total indirect cost was $7,217 ($9,354 ± $6,802.40) vs $6,802 ($9,505 ± $9,307.20) (p = 0.86), for robotic vs "open" pancreaticoduodenectomy, respectively. Since 2016, profitability was achieved in 29% of patients undergoing robotic pancreaticoduodenectomy.

CONCLUSIONS

Robotic pancreaticoduodenectomy had lower estimated blood loss and shorter length of stay. Cost of care for robotic pancreaticoduodenectomy was greater across all categories, except for total indirect cost, than "open" pancreaticoduodenectomy. For our institution, profitability was accomplished in less than one-third of patients undergoing robotic pancreaticoduodenectomy. The role of the robotic platform for pancreaticoduodenectomy needs to be discussed among all stakeholders.

Detailed Analysis of Margin Positivity and the Site of Local Recurrence After Pancreaticoduodenectomy

BACKGROUND

The association between a positive surgical margin and local recurrence after resection of pancreatic adenocarcinoma (PDAC) has been reported. Assessment of the location of the a positive margin and the specific site of local recurrence has not been well described.

METHODS

A prospectively maintained database was queried for patients who underwent R0/R1 pancreaticoduodenectomy for PDAC between 2000 and 2015. The pancreatic, posterior, gastric/duodenal, anterior peritoneal, and bile duct margins were routinely assessed. Postoperative imaging was reviewed for the site of first recurrence, and local recurrence was defined as recurrence located in the remnant pancreas, surgical bed, or retroperitoneal site outside the surgical bed.

RESULTS

During the study period, 891 patients underwent pancreaticoduodenectomy, and 390 patients had an initial local recurrence with or without distant metastases. The 5-year cumulative incidence of local recurrence by site included the remnant pancreas (4%; 95% confidence interval [CI], 3-5%), the surgical bed (35%; 95% CI, 32-39%), and other regional retroperitoneal site (4%; 95% CI, 3-6%). In the univariate analysis, positive posterior margin (hazard ratio [HR], 1.50; 95% CI, 1.17-1.91; p = 0.001) and positive lymph nodes (HR, 1.36; 95% CI, 1.06-1.75; p = 0.017) were associated with surgical bed recurrence, and in the multivariate analysis, positive posterior margin remained significant (HR, 1.40; 95% CI, 1.09-1.81; p = 0.009). An isolated local recurrence was found in 197 patients, and a positive posterior margin was associated with surgical bed recurrence in this subgroup (HR, 1.51; 95% CI, 1.08-2.10; p = 0.016).

CONCLUSION

In this study, the primary association between site of margin positivity and site of local recurrence was between the posterior margin and surgical bed recurrence. Given this association and the limited ability to modify this margin intraoperatively, preoperative assessment should be emphasized.

Impact of intraoperative margin clearance on survival following pancreatoduodenectomy for pancreatic cancer: a systematic review and meta-analysis

The use of intraoperative margin revision to achieve margin clearance in patients undergoing pancreatoduodenectomy for pancreatic cancer is controversial. We performed a systematic review and meta-analysis to summarize the evidence of intraoperative margin revisions of the pancreatic neck and its impact on overall survival (OS). Nine studies with 4501 patients were included. Patient cohort was stratified in an R0R0-group (negative margin on frozen and permanent section), R1R0-group (revised positive margin on frozen section which turned negative on permanent section), and R1R1-group (positive margin on frozen and permanent section despite margin revision). OS was higher in the R1R0-group (HR 0.83, 95% CI 0.72-0.96, P = 0.01) compared to the R1R1-group but lower compared to the R0R0-group (HR 1.20; 95% CI 1.05-1.37, P = 0.008), respectively. Subgroup analyses on the use of different margin clearance definitions confirmed an OS benefit in the R1R0-group compared to the R1R1-group (HR 0.81; 95% CI 0.65-0.99, P = 0.04). In conclusion, intraoperative margin clearance of the pancreatic neck margin is associated with improved OS while residual tumor indicates aggressive tumor biology. Consensus definitions on margin terminologies, clearance, and surgical techniques are required.

Pattern of local recurrence after curative resection in pancreatic ductal adenocarcinoma according to the initial location of the tumor

BACKGROUND/PURPOSE

The aim of the present study was to identify the types of recurrence in pancreatic ductal adenocarcinoma (PDAC) and discover the frequent location of the local recurrence.

METHODS

This study included 361 patients with PDAC who underwent curative-intent surgery between 2007-2014.

RESULTS

Among 361 patients, 75.1% (n = 271) developed recurrence during the follow-up period. The 5-year overall survival rate of recurred patients was 8.3%. The patterns of recurrence were classified as local (17.7%), systemic (62.0%), and loco-systemic (20.3%). According to the preoperative tumor locations, patients with uncinate and head cancer showed higher rates of local recurrence than those with body and tail cancer (47.8% vs 17.2%, P < .001). When comparing uncinate and head cancer only, patients with uncinate cancer had much more frequent local recurrence around the superior mesenteric artery/vein (M zone) than around the hepatoduodenal ligament/common hepatic artery (H zone). Patients with head cancer had a higher rate of local recurrence in the H zone (H zone vs M zone; 53.5% vs 81.4% in uncinate cancer, P = .001; 66.7% vs 44.4% in head cancer, P = .056).

CONCLUSION

Discovering the patterns of recurrence and frequent locations of recurrence may assist in local control as well as in the development of a customized individual approach for each patient.

Margin-Positive Pancreatic Ductal Adenocarcinoma during Pancreaticoduodenectomy: Additional Resection Does Not Improve Survival

BACKGROUND

The impact of resecting positive margins during pancreaticoduodenectomy (PD) for pancreatic ductal adenocarcinoma (PDA) remains debated. Additionally, the survival benefit of resecting multiple positive margins is unknown.

METHODS

We identified patients with PDA who underwent PD from 2006 to 2015. Pancreatic neck, bile duct, and uncinate frozen section margins were assessed before and after resection of positive margins. Survival curves were compared with log-rank tests. Multivariable Cox regression assessed the effect of margin status on overall survival.

RESULTS

Of 501 patients identified, 17.3%, 5.3%, and 19.7% had an initially positive uncinate, bile duct, or neck margin, respectively. Among initially positive bile duct and neck margins, 77.8% and 67.0% were resected, respectively. Although median survival was decreased among patients with any positive margins (15.6 vs. 20.9 months; p = 0.006), it was similar among patients with positive bile duct or neck margins with or without R1 to R0 resection (17.0 vs. 15.6 months; p = 0.20). Median survival with and without positive uncinate margins was 13.8 vs. 19.7 months (p = 0.04). Uncinate margins were never resected. Resection of additional margins when the uncinate was concurrently positive was not associated with improved survival (p = 0.37). Patients with positive margins who received adjuvant therapy had improved survival, regardless of margin resection (p = 0.03). Adjuvant therapy was independently protective against death (hazard ratio 0.6, 95% CI 0.5-0.7).

CONCLUSIONS

Positive PD margins at any position are associated with reduced overall survival; however, resection of additional margins may not improve survival, particularly with concurrently positive uncinate margins. Adjuvant chemotherapy improves survival with positive margins, regardless of resection.

Margin Status Impacts Survival after Pancreaticoduodenectomy but Negative Margins Should Not be Pursued

Negative margins are the goal with pancreaticoduodenectomy for pancreatic adenocarcinoma. Thereby, margins are assessed intraoperatively with frozen section analysis and negative margins are pursued. This study was undertaken to determine the impact of margin status with pancreaticoduodenectomy for pancreatic adenocarcinoma and the value of extending resections to achieve negative margins. The intraoperative frozen section analysis and final margins for 448 patients undergoing pancreaticoduodenectomy for pancreatic adenocarcinoma were assessed and their impact on survival was determined. Median data are presented. Two hundred ninety-eight (67%) patients had negative margins (R0), an additional 110 (25%) patients had microscopically positive and macroscopically negative margins (R1), and an additional 40 (9%) patients had initially positive microscopic margins, which became negative with further resection (R1 å R0). R0 resections were more likely to have smaller tumors, earlier T grade, earlier N grade, lower American Joint Committee on Cancer stage, and less frequent extrapancreatic extension ( P ≤ 0.03 for each). Survival was better with R0 resections than R1 resections (20 vs 12 months, P < 0.001); extending resections to achieve negative margins (i.e., R1 ! R0) did not improve survival beyond R1 resections (14 vs 12 months, P = 0.19). Survival after pancreaticoduodenectomy is disappointing. Patients with initial negative margins do best. Positive microscopic margins reflect more aggressive tumor-specific factors and lead to abbreviated survival even with extended resections to achieve negative margins (i.e., R1 ! R0). With an initial positive margin, pursuing negative margins does not improve survival and, thereby, negative margins should not be “chased.”

Systematic Review of Surgical and Percutaneous Irreversible Electroporation in the Treatment of Locally Advanced Pancreatic Cancer

OBJECTIVE

The aim of the present systematic review was to collect, analyze, and critically evaluate the role of irreversible electroporation (IRE) in locally advanced pancreatic cancer (LAPC). Furthermore, we sought to analyze the different approaches of IRE (open, laparoscopic, and percutaneous) and assess the relative outcomes.

METHODS

A systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Using the MEDLINE (1966-2018), Scopus (2004-2018), Google Scholar (2004-2018) and ClinicalTrials.gov databases, eligible articles published up to August 2018 were included. The following keywords were applied: 'irreversible electroporation', 'IRE', 'LAPC', 'unresectable pancreatic cancer', 'palliative treatment', 'locally advanced pancreatic cancer', 'ablation' and 'ablative treatment'.

RESULTS

IRE for LAPC was feasible and safe; however, it was associated with morbidity in approximately one in three patients, some of whom experienced serious complications, particularly after surgical IRE. In addition, while mortality following IRE was uncommon, it did occur in 2% of patients. While some studies suggested a survival benefit, others failed to note an improvement in long-term outcomes following IRE compared with other therapies.

CONCLUSIONS

Providers and patients need to be aware of the potential morbidity and mortality associated with IRE. In addition, based on the literature to date, the survival benefit of IRE for LAPC remains to be elucidated. Conclusive and definitive evidence to support a survival benefit of IRE does not currently exist. Future multicenter, randomized, prospective trials are needed to clarify the role of IRE in patients with LAPC.

Can post-hoc video review of robotic pancreaticoduodenectomy predict portal/superior mesenteric vein margin status in pancreatic adenocarcinoma?

BACKGROUND

Achieving margin negative resection is a significant determinant of outcome in pancreatic adenocarcinoma (PDA). However, because of the fibrotic nature of PDA, it can be difficult to discriminate fibrosis from active disease intra-operatively. We sought to determine if post-hoc video review of robotic pancreatico-duodenectomy (RPD) could predict the portal/superior mesenteric vein (PV/SMV) margin status on final pathology.

METHODS

Experienced pancreatic surgeons, blinded to patient and operative variables, reviewed the PV/SMV margin for available RPD videos of consecutive PDA patients from 9/2012 through 6/2017.

RESULTS

107 RPD videos were reviewed. Of 76 patients (71%) predicted to have a negative vein margin on video review, 20 patients (26%) had a pathologic positive margin. 25 of 31 patients (81%) predicted to have positive margin on video review were positive on pathology. The specificity of video prediction was 90.3% with a sensitivity of 55.6% and an accuracy of 75.7%.

CONCLUSION

Post-hoc video review prediction is unable to reliably predict a positive (R1) margin at the portal vein/SMV, suggesting that intra-operative clinical assessment may be suboptimal in determining the need for more extensive resections.

Understanding the Trauma/Acute Care Surgery Workforce

As the roles of trauma/acute care surgeons continue to evolve, it is imperative that health-care systems adapt to meet workforce needs. Tailoring retention strategies that elicit workforce satisfaction ensure continued coverage that is mutually beneficial to surgeons and health-care systems. We sought to elicit factors related to career characteristics and expectations of the trauma/acute care surgery (ACS) workforce to assist with such future progress. In this study, 1552 Eastern Association for the Surgery of Trauma members were anonymously surveyed. Data collected included demographics, career expectations, and motivators of trauma/ACS. Four hundred eight (26%) Eastern Association for the Surgery of Trauma members responded. Respondents were 78 per cent male and had a median age of 47.3 years. Forty-six per cent of surgeons reported earning $351K–$475K and 23 per cent >$475K. At this point in their career, 49 per cent of surgeons felt quality of life was “most important”, followed by 31 per cent career ambitions and 13 per cent salary. Prominent career satisfiers were patient care and teaching. Greatest detractors were burnout, bureaucracy, and work environment. Eighty per cent would change jobs in the final 10 years of practice, 31 per cent because of family/retirement, 29 per cent because of professional growth, 24 per cent because of workload, and 7 per cent because of salary. This study could be used to help develop trauma/ACS workforce strategies. This workforce remains mobile into late career; personal happiness and patient ownership overshadow financial rewards, and most prefer a total and shared patient care model compared with no patient ownership. Burnout, bureaucracy, and work environment are dominant detractors of job satisfaction among surveyed trauma/ACS surgeons.

Impact of resection margin status on recurrence and survival in pancreatic cancer surgery

BACKGROUND

The prognosis of patients with pancreatic ductal adenocarcinoma (PDAC) is poor and selection of patients for surgery is challenging. This study examined the impact of a positive resection margin (R1) on locoregional recurrence (LRR) and overall survival (OS); and also aimed to identified tumour characteristics and/or technical factors associated with a positive resection margin in patients with PDAC.

METHODS

Patients scheduled for pancreatic resection for PDAC between 2006 and 2016 were identified from an institutional database. The effect of resection margin status, patient characteristics and tumour characteristics on LRR, distant metastasis and OS was assessed.

RESULTS

A total of 322 patients underwent pancreatectomy for PDAC. A positive resection (R1) margin was found in 129 patients (40·1 per cent); this was associated with decreased OS compared with that in patients with an R0 margin (median 15 (95 per cent c.i. 13 to 17) versus 22 months; P < 0·001). R1 status was associated with reduced time to LRR (median 16 versus 36 (not estimated, n.e.) months; P = 0·002). Disease recurrence patterns were similar in the R1 and R0 groups. Risk factors for early recurrence were tumour stage, positive lymph nodes (N1) and perineural invasion. Among 100 patients with N0 disease, R1 status was associated with shorter OS compared with R0 resection (median 17 (10 to 24) versus 45 (n.e.) months; P = 0·002), whereas R status was not related to OS in 222 patients with N1 disease (median 14 (12 to 16) versus 17 (15 to 19) months after R1 and R0 resection respectively; P = 0·068).

CONCLUSION

Although pancreatic resection with a positive margin was associated with poor survival and early recurrence, particularly in patients with N1 disease, disease recurrence patterns were similar between R1 and R0 groups.

Margin status and long-term prognosis of primary pancreatic neuroendocrine tumor after curative resection: Results from the US Neuroendocrine Tumor Study Group

BACKGROUND

The impact of margin status on resection of primary pancreatic neuroendocrine tumors has been poorly defined. The objectives of the present study were to determine the impact of margin status on long-term survival of patients with pancreatic neuroendocrine tumors after curative resection and evaluate the impact of reresection to obtain a microscopically negative margin.

METHODS

Patients who underwent curative-intent resection for pancreatic neuroendocrine tumors between 2000 and 2016 were identified at 8 hepatobiliary centers. Overall and recurrence-free survival were analyzed relative to surgical margin status using univariable and multivariable analyses.

RESULTS

Among 1,020 patients, 866 (84.9%) had an R0 (>1 mm margin) resection, whereas 154 (15.1%) had an R1 (≤1 mm margin) resection. R1 resection was associated with a worse recurrence-free survival (10-year recurrence-free survival, R1 47.3% vs R0 62.8%, hazard ratio 1.8, 95% confidence interval 1.2-2.7, P = .002); residual tumor at either the transection margin (R1t) or the mobilization margin (R1m) was associated with increased recurrence versus R0 (R1t versus R0: hazard ratio 1.8, 95% confidence interval 1.0-3.0, P = .033; R1m versus R0: hazard ratio 1.3, 95% confidence interval 1.0-1.7, P = .060). In contrast, margin status was not associated with overall survival (10-year overall survival, R1 71.1% vs R0 71.8%, P = .392). Intraoperatively, 539 (53.6%) patients had frozen section evaluation of the surgical margin; 49 (9.1%) patients had a positive margin on frozen section analysis; 38 of the 49 patients (77.6%) had reresection, and a final R0 (secondary R0) margin was achieved in 30 patients (78.9%). Extending resection to achieve an R0 status remained associated with worse overall survival (hazard ratio 3.1, 95% confidence interval 1.6-6.2, P = .001) and recurrence-free survival (hazard ratio 2.6, 95% confidence interval 1.4-5.0, P = .004) compared with primary R0 resection. On multivariable analyses, tumor-specific factors, such as cellular differentiation, perineural invasion, Ki-67 index, and major vascular invasion, rather than surgical margin, were associated with long-term outcomes.

CONCLUSION

Margin status was not associated with long-term survival. The reresection of an initially positive surgical margin to achieve a negative margin did not improve the outcome of patients with pancreatic neuroendocrine tumors. Parenchymal-sparing pancreatic procedures for pancreatic neuroendocrine tumors may be appropriate when feasible.

Clinical Management: Resectable Disease

Despite the identification of more active systemic therapy combinations for pancreatic cancer, cures remain elusive and feasible only in patients with localized, operable disease. When examining outcome data from phase III adjuvant trials conducted during the past decade, the survival for patients with localized disease has improved, likely owing to a combination of factors including more active adjuvant therapy and improved surgical and perioperative care. Perhaps the greatest recent change in the care of patients with localized pancreatic cancer has been the extension of surgery to tumors previously thought to be inoperable because of involvement of major blood vessels. These so-called "borderline resectable pancreatic cancers" have now been objectively defined, and their management is being studied in randomized trials. This has been made feasible by the availability of more active systemic therapy combinations that are increasingly being used in the neoadjuvant setting. Given the increasing activity of systemic regimens, the challenges in delivering such therapy in the postoperative setting, and the numerous novel agents in late stages of clinical development, it is reasonable to hypothesize that the neoadjuvant setting may eventually become the standard of care for patients with resectable disease.

Intra-Operative Frozen Section Histology of the Pancreatic Resection Margins and Clinical Outcome of Patients with Adenocarcinoma of the Head of the Pancreas Undergoing Pancreaticoduodenectomy

BACKGROUND The aim of this study was to compare the clinical outcome in patients with pancreatic ductal adenocarcinoma who underwent frozen section and paraffin section histology of the surgical resection margins during pancreaticoduodenectomy. MATERIAL AND METHODS Frozen section and routine paraffin section histopathology were performed using the following categories: R0 (no tumor cells at the surgical resection margin), R1 (tumor cells at, or within 1 mm, of the surgical resection margin), and R2 (tumor seen macroscopically at the surgical resection margin). R1 and R2 patients underwent additional resection to achieve R0. RESULTS Of 346 patients who underwent pancreaticoduodenectomy, frozen section histology showed positive resection margins in 22 patients (9.2%) and paraffin section histology was positive in 20 patients (8.4%). The OS was nine months in frozen section-positive patients and 20 months in frozen section-negative patients (p=0.001). The OS rates were significantly different between the paraffin section-positive and paraffin section-negative patients (11 months vs. 21 months) (p=0.001). Univariate and multivariate analysis showed that increased tumor size, high tumor grade, lymph node metastases, a positive superior mesenteric artery and retroperitoneal margin, and a positive resection margin on frozen section were significantly correlated with reduced OS (p<0.05). Twenty-two patients with positive resection margins on frozen section histology underwent further resection; R0 was achieved in 14 patients, with no significant difference in OS. CONCLUSIONS For patients who underwent pancreaticoduodenectomy for pancreatic carcinoma with positive resection margins on frozen section, further surgical resection to achieve R0 had no significant positive impact on OS.

Staging pancreatic carcinoma by computed tomography

Pancreatic carcinoma is becoming more common in our environment; the mortality rate for this tumor has barely changed over the last 20 years. Early diagnosis and accurate staging are crucial to ensure an appropriate therapeutic approach, which should aim to improve survival in patients in whom complete resection is possible and to minimize surgical morbidity and mortality in those with a high risk of residual disease after the intervention. Various imaging techniques are used for tumor staging: multidetector computed tomography (CT), magnetic resonance imaging, positron emission tomography (PET)-CT, endoscopic ultrasound, and diagnostic laparoscopy. Currently, multidetector CT is the technique of choice for the study of pancreatic tumors; thus, this article aims to review the state of the art in staging adenocarcinoma of the pancreas, focusing mainly on the applications and limitations of this technique.

Integration of different criteria for borderline resectable pancreatic cancer using classification tree analysis: the use of radiological tumour-vascular interface in correlation with surgical and pathological outcomes

AIM

To integrate various criteria for borderline resectable pancreatic cancer (BRPC) based on radiological parameters using classification tree analysis.

MATERIALS AND METHODS

The institutional review board approved this retrospective study and waived the requirement for informed consent. Two hundred and thirty-five tumour-vein interfaces and 67 tumour-artery interfaces in 245 patients with surgically confirmed pancreatic ductal adenocarcinoma who underwent both preoperative computed tomography (CT) and magnetic resonance imaging (MRI) were assessed by two independent readers. Radiological parameters for evaluation of the tumour-vascular interface were boundary, length of interface, degree of circumferential interface, and contour deformity of affected vessels. Classification tree analysis was performed to determine parameters associated with vascular invasion using pathological and surgical results as the reference standard.

RESULTS

In the classification tree analysis for the tumour-vein interface, contour deformity and degree of circumferential interface were the first and second determining factors, respectively, for both surgical and pathological vascular invasion. For the tumour-artery interface, boundary and degree of circumferential interface were the first and second determining factors for surgical invasion, while contour deformity and length of interface were the first and second determining factors for pathological invasion. The BRPC group of modified criteria arbitrarily formed based on the results had similar surgical (74.1-81.6%) and pathological (54.3-63.3%) venous invasion compared to that of the National Comprehensive Cancer Network (NCCN) criteria, and the lowest surgical (33.3%) and pathological (6.7%) arterial invasion compared with those in previously established criteria for BRPC (43.3-55.6% and 22.2-26.1%, respectively).

CONCLUSION

Various criteria for BRPCs were integrated using classification tree analysis, and a modified criterion for BRPC, which provides satisfactory results, was established.

Redefining the Positive Margin in Pancreatic Cancer: Impact on Patterns of Failure, Long-Term Survival and Adjuvant Therapy

PURPOSE

There is debate regarding the definition and clinical significance of margin clearance in pancreatic ductal adenocarcinoma (PDA). A comprehensive archival analysis of surgical resection margins was performed to determine the effect on locoregional recurrence and survival, and the impact of adjuvant therapy in PDA.

METHODS

We identified 105 patients with resected PDA. Pancreatic, anterior, bile duct, and posterior surgical resection margins (PM; posterior surface, uncinate and vascular groove) were identified. Three pathologists reviewed all archival surgical specimens and recategorized each margin as tumor at ink/transected, <0.5, 0.5-1, >1-2, or >2 mm from the inked surface. The impact of these and other clinical variables was assessed on local control, disease-free survival (DFS), and overall survival (OS).

RESULTS

Among all margins, PM clearance up to 2 mm was prognostic of DFS (p = 0.01) and OS (p = 0.01). Dichotomizing the PM at 2 mm revealed it to be an independent predictor of local recurrence-free survival [hazard ratio HR] 0.20, 95% confidence interval [CI] 0.048-0.881, p = 0.033), DFS (HR 0.46, 95% CI 0.22-0.96, p = 0.03), and OS (HR 0.31, 95% CI 0.14-0.74, p = 0.008). A margin status of >2 mm was also prognostic of OS in patients who received adjuvant chemotherapy (HR 0.31, 95% CI 0.11-0.89, p = 0.03), however this difference was mitigated in patients receiving adjuvant chemoradiotherapy (HR 0.40, 95% CI 0.10-1.58, p = 0.19).

CONCLUSION

These data highlight the clinical significance of the PM and the lack of significance of other resection margins. Clearance in excess of 2 mm should be considered to improve long-term clinical outcomes. The use of adjuvant radiotherapy should be strongly considered in patients with PMs <2 mm.

Impact of Intraoperative Re-resection to Achieve R0 Status on Survival in Patients With Pancreatic Cancer: A Single-center Experience With 483 Patients

OBJECTIVE

The aim of this study was to test the hypothesis that intraoperative frozen section (FS) and re-resection results to achieve R0 status are associated with different long-term outcomes in pancreatic cancer patients.

BACKGROUND

Recent data have challenged the survival benefit of additional resection in patients with pancreatic cancer in case of positive FS to achieve clear pathological section (PS).

METHODS

Patients who underwent surgery for exocrine pancreatic malignancy with curative intent were identified from a prospective database. Data were stratified by resection margin (group I: FS-R0 → PS-R0; group II: FS-R1 → PS-R0; group III: FS-R1 → PS-R1). Associations with survival were analyzed by univariate and multivariate analyses.

RESULTS

A total of 483 patients met the inclusion criteria. Of these, 61 patients were excluded due to R2 or Rx status. Three hundred seventeen (75%) patients were allocated to margin group I, 32 (8%) to group II, and 73 (17%) to group III. Median overall survival in group I, II, and III was 29, 36, and 12 months (P < 0.001). There was no significant difference in survival between patients in Group I and II (P = 0.849), whereas patients in group III had significantly poorer outcome than group I (P < 0.001) and II (P = 0.039). The prognostic value of margin group status was confirmed on multivariate analysis (hazard ratio = 1.694, 95% confidence interval 1.175-2.442).

CONCLUSIONS

FS analysis with intraoperative re-resection should be performed routinely in patients undergoing pancreatic cancer surgery with the aim to achieve a R0 resection.

Does adjuvant therapy improve overall survival for stage IA/B pancreatic adenocarcinoma?

BACKGROUND

Current guidelines recommend adjuvant chemotherapy for resected pancreatic adenocarcinoma (PDAC). However, no studies have addressed its survival benefit for stage I patients as they comprise <10% of PDAC.

METHODS

Using the NCDB 2006-2012, resected PDAC patients with stage I disease who received adjuvant therapy (chemotherapy or chemoradiation) were analyzed. Factors associated with overall survival (OS) were identified.

RESULTS

3909 patients with resected stage IA or IB PDAC were identified. Median OS was 60.3 months (mo) for stage IA and 36.9 mo for IB. 45.5% received adjuvant chemotherapy; 19.9% received adjuvant chemoradiation. There was OS benefit for both stage IA/IB patients with adjuvant chemotherapy (HR = 0.73 and 0.76 for IA and IB, respectively, p = 0.002 and <0.001). For patients with Stage IA disease (n = 1,477, 37.8%), age ≥70 (p < 0.001), higher grade (p < 0.001), ≤10 lymph nodes examined (p = 0.008), positive margins (p < 0.001), and receipt of adjuvant chemoradiation (p = 0.002) were associated with worse OS. For stage IB patients (n = 2,432, 62.2%), similar associations were observed with the exception of adjuvant chemoradiation whereby there was no significant association (p = 0.35).

CONCLUSION

Adjuvant chemotherapy was associated with an OS benefit for patients with stage I PDAC; adjuvant chemoradiation was either of no benefit or associated with worse OS.

Does revision of resection margins based on frozen section improve overall survival following pancreatoduodenectomy for pancreatic ductal adenocarcinoma? A meta-analysis

BACKGROUND

Margin status is the main surgical determinant of long-term outcome in pancreatic cancer. Intraoperative frozen section (IOFS) detects microscopic positive margins at a stage when margin revision is possible. The aim of this study was to determine if IOFS driven-revision of pancreatic resection margin(s) improves overall survival (OS) in pancreatic cancer.

METHODS

A systematic review of major reference databases was undertaken. Patients were divided into 3 groups based on initial FS (FSR0 for negative margin and FSR1 for positive microscopic margin) and final Permanent Section report (PSR0 for negative margin and PSR1 for positive microscopic margin): Group 1 (FSR0 → PSR0), Group 2 (FSR1 → PSR0), and Group 3 (FSR1 → PSR1). Patients in Groups 2 and 3 had surgical revision of the FSR1 margin. Data was meta-analysed.

RESULTS

4 studies included in the final analysis. No difference in OS and incidence of lymph node metastases between Groups 2 and 3 (P = 0.590 and P = 0.410).

CONCLUSIONS

IOFS-based revision of R1 pancreatic resection margin does not improve OS, even when it results in an R0 margin. This suggests that any benefit of margin revision based on FS is over-ridden by markers of more advanced or aggressive disease.

A systematic review of the role of periadventitial dissection of the superior mesenteric artery in affecting margin status after pancreatoduodenectomy for pancreatic adenocarcinoma

BACKGROUND

Resectable pancreatic ductal adenocarcinoma continues to carry a poor prognosis. Of the controllable clinical variables known to affect outcome, margin status is paramount. Though the importance of a R0 resection is generally accepted, not all margins are easily managed. The superior mesenteric artery [SMA] in particular is the most challenging to clear. The aim of this study was to systematically review the literature with specific focus on the role of a SMA periadventitial dissection during PD and it's effect on margin status in pancreatic adenocarcinoma.

STUDY DESIGN

The MEDLINE, EMBASE and Cochrane databases were searched for abstracts that addressed the effect of margin status on survival and recurrence following pancreaticoduodenectomy [PD]. Quantitative analysis was performed.

RESULTS

The overall incidence of a R1 resection ranged from 16% to 79%. The margin that was most often positive following PD was the SMA margin, which was positive in 15-45% of resected specimens. Most studies suggested that a positive margin was associated with decreased survival. No consistent definition of R0 resection was observed.

CONCLUSIONS

Margin positivity in resectable pancreatic adenocarcinoma is associated with poor survival. Inability to clear the SMA margin is the most common cause of incomplete resection. More complete and consistently reported data are needed to evaluate the potential effect of periadventitial SMA dissection on margin status, local recurrence, or survival.

Pathologic Evaluation and Reporting of Intraductal Papillary Mucinous Neoplasms of the Pancreas and Other Tumoral Intraepithelial Neoplasms of Pancreatobiliary Tract: Recommendations of Verona Consensus Meeting

BACKGROUND

There are no established guidelines for pathologic diagnosis/reporting of intraductal papillary mucinous neoplasms (IPMNs).

DESIGN

An international multidisciplinary group, brought together by the Verona Pancreas Group in Italy-2013, was tasked to devise recommendations.

RESULTS

(1) Crucial to rule out invasive carcinoma with extensive (if not complete) sampling. (2) Invasive component is to be documented in a full synoptic report including its size, type, grade, and stage. (3) The term "minimally invasive" should be avoided; instead, invasion size with stage and substaging of T1 (1a, b, c; ≤ 0.5, > 0.5-≤ 1, > 1 cm) is to be documented. (4) Largest diameter of the invasion, not the distance from the nearest duct, is to be used. (5) A category of "indeterminate/(suspicious) for invasion" is acceptable for rare cases. (6) The term "malignant" IPMN should be avoided. (7) The highest grade of dysplasia in the non-invasive component is to be documented separately. (8) Lesion size is to be correlated with imaging findings in cysts with rupture. (9) The main duct diameter and, if possible, its involvement are to be documented; however, it is not required to provide main versus branch duct classification in the resected tumor. (10) Subtyping as gastric/intestinal/pancreatobiliary/oncocytic/mixed is of value. (11) Frozen section is to be performed highly selectively, with appreciation of its shortcomings. (12) These principles also apply to other similar tumoral intraepithelial neoplasms (mucinous cystic neoplasms, intra-ampullary, and intra-biliary/cholecystic).

CONCLUSIONS

These recommendations will ensure proper communication of salient tumor characteristics to the management teams, accurate comparison of data between analyses, and development of more effective management algorithms.

Trends in Receipt and Timing of Multimodality Therapy in Early-Stage Pancreatic Cancer

INTRODUCTION

Pancreatic cancer is considered a systemic disease at presentation. Therefore, multimodality therapy with surgical resection and chemotherapy is the standard of care for locoregional disease. We described treatment patterns and time trends with regard to age and treatment center in the receipt of multimodality therapy.

METHODS

We used the National Cancer Data Base to identify patients ≥18 years old with stage I and II pancreatic adenocarcinoma. Treatment was defined as no treatment, resection only, chemotherapy only, or multimodality therapy, which consisted of both chemotherapy (neoadjuvant or adjuvant) and resection. Trends in the receipt and type of treatment were compared.

RESULTS

Of 39,441 patients, 22.8% of patients received no treatment, 18.5% received chemotherapy only, 23.0% underwent surgical resection alone, and 35.8% of patients received multimodality therapy. Receipt of multimodality therapy increased from 31.3% in 2004 to 37.9% in 2011 (p < 0.0001). Patients >55 years were less likely to receive multimodality therapy (56-64 years: OR 0.83, 95% CI 0.78-0.89; 65-75: OR 0.60, 95% CI 0.55-0.65; ≥76: OR 0.17, 95% CI 0.16-0.19 compared to patients 18-55). Compared to community hospitals, patients treated at an NCI-designated center were more likely to receive multimodality therapy (OR 1.62, 95% CI 1.46-1.81) and, if they received multimodality therapy, delivery of chemotherapy in the neoadjuvant compared to adjuvant setting (OR 2.82, 95% CI 2.00-3.98).

CONCLUSION

Despite increased use of multimodality therapy, it remains underutilized in all patients and especially in older patients. Receipt of multimodality therapy and neoadjuvant therapy is highly dependent on treatment at NCI-designated cancer centers.

The importance of surgical margins in pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive disease with a grim prognosis. Surgical resection offers the best chance for long-term survival, yet recurrence rates are high and outcomes are poor. The influence of margin status in PDAC is controversial, as conflicting data have been plagued by a lack of standardization in margin definitions, pathologic analysis, and reporting. Despite recent efforts, international consensus is still needed for this disease.

Meta-analysis of radical resection rates and margin assessment in pancreatic cancer

BACKGROUND

R0 resection rates (complete tumour removal with negative resection margins) in pancreatic cancer are 70-80 per cent when a 0-mm margin is used, declining to 15-24 per cent with a 1-mm margin. This review evaluated the R0 resection rates according to different margin definitions and techniques.

METHODS

Three databases (MEDLINE from 1946, PubMed from 1946 and Embase from 1949) were searched to mid-October 2014. The search terms included 'pancreatectomy OR pancreaticoduodenectomy' and 'margin'. A meta-analysis was performed with studies in three groups: group 1, axial slicing technique (minimum 1-mm margin); group 2, other slicing techniques (minimum 1-mm margin); and group 3, studies with minimum 0-mm margin.

RESULTS

The R0 rates were 29 (95 per cent c.i. 26 to 32) per cent in group 1 (8 studies; 882 patients) and 49 (47 to 52) per cent in group 2 (6 studies; 1568 patients). The combined R0 rate (groups 1 and 2) was 41 (40 to 43) per cent. The R0 rate in group 3 (7 studies; 1926 patients) with a 0-mm margin was 72 (70 to 74) per cent The survival hazard ratios (R1 resection/R0 resection) revealed a reduction in the risk of death of at least 22 per cent in group 1, 12 per cent in group 2 and 23 per cent in group 3 with an R0 compared with an R1 resection. Local recurrence occurred more frequently with an R1 resection in most studies.

CONCLUSION

Margin clearance definitions affect R0 resection rates in pancreatic cancer surgery. This review collates individual studies providing an estimate of achievable R0 rates, creating a benchmark for future trials.