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.

Five-year recurrence/survival after pancreatoduodenectomy for pancreatic adenocarcinoma: does pre-existing diabetes matter? Results from the Recurrence After Whipple's (RAW) study

BACKGROUND

Diabetes mellitus (DM) has a complex relationship with pancreatic cancer. This study examines the impact of preoperative DM, both recent-onset and pre-existing, on long-term outcomes following pancreatoduodenectomy (PD) for pancreatic ductal adenocarcinoma (PDAC).

METHODS

Data were extracted from the Recurrence After Whipple's (RAW) study, a multi-centre cohort of PD for pancreatic head malignancy (2012-2015). Recurrence and five-year survival rates of patients with DM were compared to those without, and subgroup analysis performed to compare patients with recent-onset DM (less than one year) to patients with established DM.

RESULTS

Out of 758 patients included, 187 (24.7%) had DM, of whom, 47 of the 187 (25.1%) had recent-onset DM. There was no difference in the rate of postoperative pancreatic fistula (DM: 5.9% vs no DM 9.8%; p = 0.11), five-year survival (DM: 24.1% vs no DM: 22.9%; p = 0.77) or five-year recurrence (DM: 71.7% vs no DM: 67.4%; p = 0.32). There was also no difference between patients with recent-onset DM and patients with established DM in postoperative outcomes, recurrence, or survival.

CONCLUSION

We found no difference in five-year recurrence and survival between diabetic patients and those without diabetes. Patients with pre-existing DM should be evaluated for PD on a comparable basis to non-diabetic patients.

Systematic review of challenging issues in pathology of intraductal papillary mucinous neoplasms

BACKGROUND

Intraductal papillary mucinous neoplasms (IPMNs) are a cystic precursor to pancreatic cancer. IPMNs deemed clinically to be at high-risk for malignant progression are frequently treated with surgical resection, and pathological examination of the pancreatectomy specimen is a key component of the clinical care of IPMN patients.

METHODS

Systematic literature reviews were conducted around eight topics of clinical relevance in the examination of pathological specimens in patients undergoing resection of IPMN.

RESULTS

This review provides updated perspectives on morphological subtyping of IPMNs, classification of intraductal oncocytic papillary neoplasms, nomenclature for high-grade dysplasia, assessment of T stage, distinction of carcinoma associated or concomitant with IPMN, role of molecular assessment of IPMN tissue, role of intraoperative assessment by frozen section, and preoperative evaluation of cyst fluid cytology.

CONCLUSIONS

This analysis provides the foundation for data-driven approaches to several challenging issues in the pathology of IPMNs.

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.

Perioperative Outcomes of Systematic Mesopancreas Dissection for Pancreatic and Periampullary Carcinoma at a Tertiary Referral Center From a Low Middle-Income Country

Introduction Systematic mesopancreas dissection (SMD) is an emerging surgical approach in pancreatic cancer surgery. There is still debate about early postoperative and pathological outcomes using SMD in pancreatic cancer surgery. This study has been conducted to compare the perioperative outcomes, the lymph node yield, and the margin status in patients who underwent standard pancreaticoduodenectomy (ST-PD) and SMD-PD for pancreatic and periampullary carcinoma. Methods A retrospective comparative study was conducted in patients who underwent PD for pancreatic and periampullary carcinoma in a single unit of gastrointestinal and hepatopancreatobiliary surgery at Tribhuvan University Teaching Hospital, Nepal. Early perioperative and pathological outcomes were compared between the SMD-PD and ST-PD. Results The demographic data of 30 patients who underwent SMD-PD was comparable with the historical data of 40 patients who underwent ST-PD. The intraoperative blood loss and postoperative complications were found to be comparable between ST-PD and SMD-PD. However, the median operative time for SMD-PD was longer than ST-PD (360 minutes [IQR: 90 minutes] vs. 360 minutes [IQR: 60 minutes]). The rate of margin negative resection was similar between both groups. The median lymph node yield was significantly high in patients who underwent SMD-PD (17.5 (IQR: 6.5) vs. 11 [IQR-10.75]; p < 0.05). Conclusion SMD is safe and feasible for treating periampullary carcinoma and is particularly helpful in increasing lymph node yield.

Assessment of Quality of Frozen Section Services at a Large Academic Hospital Before and After Relocation

OBJECTIVES

To determine outcomes following relocation of frozen section services (FSS) and the implementation of a dedicated gastrointestinal frozen service.

METHODS

We reviewed our FSS 6 months prior to and following FSS relocation. Satisfaction surveys were sent to surgeons and pathologists. Survey feedback resulted in a pilot of gastrointestinal subspecialist frozen section coverage.

RESULTS

There were 1,607 and 1,472 specimens from 667 and 602 patients pre- and post-FSS relocation, respectively. There was a decline in median specimen delivery time to pathology (12 vs 10 minutes, P < .001) and an increase in median time from receipt in pathology to intraoperative diagnosis (20 vs 22 minutes, P = .008) in cases with intrapathology consultation but no change without consultation (median, 19 minutes). Intrapathology consultation decreased from 19.7% (317/1,607) to 11.5% (169/1,472) (P < .001). Discordance rates between frozen section and permanent section remained low and similar (2.0% [33/1,607] vs 2.7% [40/1,472], P = .24). There was no significant change in discordance with dedicated gastrointestinal subspecialty frozen section interpretation.

CONCLUSIONS

Relocation of FSS and dedicated subspecialty interpretation may improve surgeon satisfaction but can also create workflow challenges. Pathology departments need to achieve a balance between satisfaction and adequacy to establish best frozen section coverage models.

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.

Intraoperative Positive Pancreatic Parenchymal Resection Margin: Is It a True Indication of Completion Total Pancreatectomy after Partial Pancreatectomy for Pancreatic Ductal Adenocarcinoma?

Background: Total pancreatectomy (TP) can be performed in cases with positive resection margin after partial pancreatectomy for pancreatic cancer. However, despite complete removal of the residual pancreatic parenchyme, it is questionable whether an actual R0 resection and favorable survival can be achieved. This study aimed to identify the R0 resection rate and postoperative outcomes, including survival, following completion TP (cTP) performed due to intraoperative positive margin. Methods: From 1995 to 2015, 1096 patients with pancreatic ductal adenocarcinoma underwent elective pancreatectomy at the Samsung Medical Center. Among these, 25 patients underwent cTP, which was converted during partial pancreatectomy because of a positive resection margin. To compare survival after R0 resection between the cTP R0 and pancreaticoduodenectomy (PD) R0 cases, propensity score matching was conducted to balance the baseline characteristics. Results: The R0 rate of cTP performed due to intraoperative positive margin was 84% (21/25). The overall 5-year survival rate (5YSR) in the 25 cTP cases was 8%. There was no difference in the 5YSR between the cTP R0 and cTP R1 groups (9.5% versus 0.0%, p = 0.963). However, the 5YSR of the cTP R0 group was significantly lower than that of the PD R0 group (9.5% versus 20.0%, p = 0.022). There was no distinct difference in postoperative complications between the cTP R0 versus cTP R1 and cTP R0 versus PD R0 groups. Conclusions: In cases with intraoperative positive pancreatic parenchymal resection margin, survival after cTP was not favorable. Careful patient selection is needed to perform cTP in such cases.

[Better Therapy for Pancreatic Cancer through More Radical Surgery?]

Despite advances in the treatment of pancreatic cancer, the survival of affected patients remains limited. A more radical surgical therapy could help to improve the prognosis, in particular by reducing the local recurrence rate, which is around 45% in patients with resected pancreatic cancer. In addition, patients with oligometastatic pancreatic cancer could also benefit from a more radical indication for surgery.Based on an analysis of the literature, important principles of pancreatic cancer surgery were examined.Even if even more radical surgical approaches such as an "extended" lymphadenectomy or a standard complete pancreatectomy do not bring any survival advantage, complete resection of the tumour (R0), a thorough locoregional lymphadenectomy and an adequate radical dissection in the area of the peripancreatic vessels including periarterial nerve plexuses should be the standard of pancreatic carcinoma resections. Whenever necessary to achieve an R0 resection, resections of the pancreas have to be extended, as well as additional venous vascular resections and multivisceral resections had to be performed. Simultaneous arterial vascular resections as part of pancreatic resections as well as surgical resections in oligometastatic patients should, however, be reserved for selected patients. These aspects of the surgical technique in pancreatic carcinoma mentioned above must not be neglected from the point of view of an "existing limited prognosis". On the contrary, they form the absolutely necessary basis in order to achieve good survival results in combination with system therapy. However, it may always be necessary to adapt these standards according to the age, comorbidities and wishes of the patient.

Korean Surgical Practice Guideline for Pancreatic Cancer 2021: A summary of evidence-based surgical approaches

Pancreatic cancer is the eighth most common cancer and the fifth most common cause of cancer-related deaths in Korea. Despite the increasing incidence and high mortality rate of pancreatic cancer, there are no appropriate surgical practice guidelines for the current domestic medical situation. To enable standardization of management and facilitate improvements in surgical outcome, a total of 10 pancreatic surgical experts who are members of Korean Association of Hepato-Biliary-Pancreatic Surgery have developed new recommendations that integrate the most up-to-date, evidence-based research findings and expert opinions. This is an English version of the Korean Surgical Practice Guideline for Pancreatic Cancer 2021. This guideline includes 13 surgical questions and 15 statements. Due to the lack of high-level evidence, strong recommendation is almost impossible. However, we believe that this guideline will help surgeons understand the current status of evidence and suggest what to investigate further to establish more solid recommendations in the future.

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.

Revision of Pancreatic Neck Margins Based on Intraoperative Frozen Section Analysis Is Associated With Improved Survival in Patients Undergoing Pancreatectomy for Ductal Adenocarcinoma

OBJECTIVE

To test the hypothesis that complete, tumor-free resection at the pancreatic neck, achieved either en-bloc or non-en-bloc (ie, revision based on intraoperative frozen section [FS] analysis), is associated with improved survival as compared with incomplete resection (IR) in pancreatic ductal adenocarcinoma.

SUMMARY BACKGROUND DATA

Given the likely systemic nature of pancreatic ductal adenocarcinoma, the oncologic benefit of achieving a histologically complete local resection, particularly through revision of a positive intraoperative FS at the pancreatic neck, remains controversial.

METHODS

Clinicopathologic and treatment data were reviewed for 986 consecutive patients with ductal adenocarcinoma at the head, neck, or uncinate process of the pancreas who underwent open pancreatectomy as well as intraoperative FS analysis between 1998 and 2012 at Massachusetts General Hospital and between 1998 and 2013 at the University of Verona. Overall survival (OS) and perioperative morbidity and mortality were compared across 3 groups: complete resection achieved en-bloc (CR-EB), complete resection achieved non-en-bloc (CR-NEB), and IR.

RESULTS

The CR-EB cohort comprised 749 (76%) patients, CR-NEB 159 patients (16%), and IR 78 patients (8%). Other than a higher incidence of vascular resection among CR-NEB and IR patients, no demographic, pathologic (eg, tumor grade, lymph node positivity, superior mesenteric artery involvement), or treatment factors (eg, neoadjuvant and adjuvant therapy use) differed between the groups. Median OS was significantly higher in patients with CR-EB (28 mo, P = 0.01) and CR-NEB resections (24 mo, P = 0.02) as compared with patients with IR resections (19 mo). After adjusting for clinicopathologic and treatment characteristics, CR-EB and CR-NEB margin status were found to be independent predictors of improved OS (relative to IR, CR-EB hazard ratio [HR] 0.65, 95% confidence interval [CI] 0.49-0.86; CR-NEB HR 0.69, 95% CI 0.50-0.96). There were no intergroup differences in perioperative morbidity and mortality, including rates of pancreatic fistula.

CONCLUSIONS

For patients with ductal adenocarcinoma at the head, neck, or uncinate process of the pancreas undergoing pancreatectomy, complete tumor extirpation via either en-bloc or non-en-bloc complete resection based on FS analysis is associated with improved OS, without an associated increased perioperative morbidity or mortality.

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.

The Impact of Intraoperative Frozen Section on Resection Margin Status and Survival of Patients Underwent Pancreatoduodenectomy for Distal Cholangiocarcinoma

Background

Intraoperative frozen section (FS) is broadly used during pancreaticoduodenectomy (PD) to ensure a negative margin status, but its survival benefits on obtaining a secondary R0 resection for distal cholangiocarcinoma (dCCA) is controversial and unclear.

Methods

Clinical data of 107 patients who underwent PD for dCCA was retrospectively collected and divided into different groups based on use of FS (FS and non-FS groups) and status of resection margin (pR0, sR0 and R1 groups), and clinical parameters and survival of patients were compared and analyzed accordingly.

Results

There were 50 patients in FS group with a median survival of 28 months, 57 patients in non-FS group with a median survival of 27 months. There was no statistical difference between the two groups with Kaplan-Meier survival analysis (P = 0.347). There were 98 patients in R0 group (88 in pR0 and 10 in sR0) and nine patients in R1 group, with a median survival of 29 months and 22 months respectively, which showed a better survival in R0 group than in R1 group (P = 0.006). Survival analyses between subgroups revealed difference between pR0 and R1 group (P = 0.005), while no statistical difference concerning pR0 vs. sR0 (P = 0.211) and sR0 vs. R1 groups (P = 0.262). Multivariate Cox regression analysis revealed resection margin status, pre-operative biliary drainage and lymph node invasion to be independent prognostic factors for dCCA patients.

Conclusions

Intraoperative FS should be recommended as it significantly increased the rate of R0 resection, which was positively related to a better survival. A primary R0 resection should also be encouraged and if not, a secondary R0 could be considered at the discretion of surgeons as it showed similar survival with primary R0 resection.

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.

Pancreatic Frozen Section Guides Operative Management With Few Deferrals and Errors

CONTEXT.—

Pancreatic adenocarcinoma is the third leading cause of cancer death in the United States. Surgery remains the mainstay of treatment, and frozen section analysis is used to confirm diagnosis and determine resectability and margin status.

OBJECTIVE.—

To evaluate use and accuracy of frozen section and how diagnosis impacts surgical procedure.

DESIGN.—

We reviewed patients with planned pancreatic resections between January 2014 and March 2019 with at least 1 frozen section. Pathology reports including frozen sections, preoperative cytology, and operative notes were reviewed. Frozen sections were categorized by margin, primary pancreatic diagnosis, metastasis, or vascular resectability. The deferral and error rates and surgeons' response were noted.

RESULTS.—

We identified 898 planned pancreatic resections and 221 frozen sections that were performed on 152 cases for 102 margins, 94 metastatic lesions, 20 primary diagnoses, and 5 to confirm vascular resectability. The diagnosis was deferred to permanent sections in 13 of 152 cases (8.6%) on 16 of 221 frozen sections (7.2%): 6 for metastasis, 8 for margins, and 2 for primary diagnosis. Discrepancies/errors were identified in 4 of 152 cases (2.6%) and 4 of 221 frozen sections (1.8%). Surgeon's response was different than expected in 8 of 221 frozen sections (3.6%), but their actions were explained by other intraoperative findings in 6 of 8.

CONCLUSIONS.—

Frozen section remains an important diagnostic tool used primarily for evaluation of margins and metastasis during pancreatectomy. In most cases, a definitive diagnosis is rendered, with occasional deferrals and few errors. Intraoperative findings explain most cases where surgeons act differently than expected based on frozen section diagnosis.

Improved survival after pancreatic re-resection of positive neck margin in pancreatic cancer patients. A systematic review and network meta-analysis

The oncological benefit of achieving a negative pancreatic neck margin through re-resection after a positive frozen section (FS) is debated. Aim of this network meta-analysis is to evaluate the survival benefit of re-resection after intraoperative FS neck margin examination following pancreatectomy for ductal adenocarcinoma. A systematic search of studies comparing different strategies for the management of positive FS was performed. Patients were classified in three groups based on FS and permanent section (PS): Group A (FS-, PS-R0), Group B (FS+, PS-R0), Group C (FS±, PS-R1). A frequent random-effects network-meta-analysis was made reporting the surface under the cumulative ranking (SUCRA). Primary endpoint was overall survival (OS). Secondary endpoints were pathological outcomes. Seven retrospectives studies with 4205 patients were included and 99.1% of the pancreatic resections were pancreatoduodenectomies. Group A had the highest probability of better OS (SUCRA = 90%), compared to Group B (SUCRA = 48.7%) and Group C, which was the worst prognostic scenario (SUCRA = 11.3%). Group B had still a probability of longer OS compared to Group C (SUCRA = 48.7% vs 11.3%). Pathological features were more favourable in Group A, with the highest SUCRA for T1-T2 tumors (92.6%), N0 status (89.4%), absence of perineural invasion (92.3%). Heterogeneity was low (τ-value <0.1) for OS, and moderate (τ-values: 0.1-0.6) for pT, pN, and perineural invasion. In conclusion, negative neck margin after primary resection (FS negative) or re-resection of a positive FS was associated with improved survival compared with PS-R1. However, any intraoperative positive FS can be considered as a prognostic factor associated with a more aggressive disease.

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.

Does center or surgeon volume influence adoption of minimally invasive versus open pancreatoduodenectomy? A systematic review and meta-regression

BACKGROUND

There has been increasing uptake of minimally invasive pancreatoduodenectomy during the past decade, but it remains a highly specialized procedure as benefits over open pancreatoduodenectomy remain contentious. This study aimed to evaluate current evidence on minimally invasive pancreatoduodenectomy versus open pancreatoduodenectomy in terms of impact of center volume on outcomes.

METHODS

A systematic review of articles on comparative cohort and registry studies on minimally invasive pancreatoduodenectomy versus open pancreatoduodenectomy published until 31st December 2019 were identified, and meta-analyses were performed. Primary endpoints were International Study Group on Pancreatic Fistula grade B/C postoperative pancreatic fistula and 30-day mortality.

RESULTS

After screening 7,390 studies, 43 comparative cohort studies (8,755 patients) with moderate methodological quality and 3 original registry studies (43,735 patients) were included. For the cohort studies, the median annual hospital minimally invasive pancreatoduodenectomy volume was 10. No significant differences were found in grade B/C postoperative pancreatic fistula (odds ratio: 0.98, 95% confidence interval: 0.78-1.23) or 30-day mortality (odds ratio: 1.14, 95% confidence interval: 0.65-2.01) between minimally invasive pancreatoduodenectomy when compared with open. No publication biases were present and meta-regression identified no confounding for grade B/C postoperative pancreatic fistula, center volume or 30-day mortality. Minimally invasive pancreatoduodenectomy was only strongly associated with significantly lower rates of postoperative pulmonary complications and surgical site infection, shorter length of stay, and significantly higher rates of R0 margin resections.

CONCLUSION

Minimally invasive pancreatoduodenectomy remains noninferior to open pancreatoduodenectomy for grade B/C postoperative pancreatic fistula but is strongly associated with significantly lower rates of postoperative pulmonary complications and surgical site infection. Minimally invasive pancreatoduodenectomy can be adopted safely with good outcomes irrespective of annual center resection volume.

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.

Prospective assessment of resection margin status following pancreaticoduodenectomy for pancreatic ductal adenocarcinoma after standardisation of margin definitions

BACKGROUND

Surgical resection remains the only curative treatment for pancreatic ductal adenocarcinoma (PDAC). The prognostic value of resection margin status following pancreatoduodenectomy (PD) remains controversial. Standardised pathological assessment increases positive margins but limited data is available on the significance of involved margins. We investigated the impact of resection margin status in PDAC on patient outcome.

METHOD

We identified all patients with PD for PDAC at one pancreatic cancer centre between August 2008 and December 2014. Demographic, operative, adjuvant therapeutic and survival data was obtained. Pathology data including resection margin status of specific anatomic margins was collected and analysed.

RESULTS

107 patients were included, all pathologically staged as T3 with 102 N1. 87.9% of patients were R1 of which 53.3% showed direct extension to the resection margin. Median survival for R0 patients versus R1<1 mm and R1 = 0 mm was 28.4 versus 15.4 and 25.1 versus 13.4 months. R1 = 0 mm status remained a predictor of poor outcome on multivariate analysis. Evaluation of individual margins (R1<1 mm) showed the SMV and SMA margins were associated with poorer overall survival. Multiple involved margins impacted negatively on outcome. SMA margin patient outcome with R1 = 1-1.9 mm was similar to R1=>2 mm.

CONCLUSION

Using an R1 definition of <1 mm and standardised pathology we demonstrate that R1 rates in PDAC can approach 90%. R1 = 0 mm remained an independent prognostic factor for overall survival. Using R1<1 mm we have shown that involvement of medial margins and multiple margins has significant negative impact on overall survival. We conclude that not all margin positivity has the same prognostic significance.

The AGITG GAP Study: A Phase II Study of Perioperative Gemcitabine and Nab-Paclitaxel for Resectable Pancreas Cancer

BACKGROUND

While combination therapy with nab-paclitaxel/gemcitabine (nab-gem) is effective in pancreatic ductal adenocarcinoma (PDAC), its efficacy as perioperative chemotherapy is unknown. The primary objective of this multicenter, prospective, single-arm, phase II study was to determine whether neoadjuvant therapy with nab-gem was associated with higher complete resection rates (R0) in resectable PDAC, while the secondary objectives were to determine the utility of radiological assessment of response to preoperative chemotherapy and the safety and efficacy of nab-gem as perioperative therapy.

METHODS

Patients were recruited from eight Australian sites, and 42 patients with radiologically defined resectable PDAC and an Eastern Cooperative Oncology Group performance status of 0-2 were enrolled. Participants received two cycles of preoperative nab-paclitaxel 125 mg/m² and gemcitabine 1000 mg/m² on days 1, 8, and 15 (28-day cycle) presurgery, and four cycles postoperatively. Early response to chemotherapy was measured with fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) scans on day 15.

RESULTS

Preoperative nab-gem was completed by 93% of participants, but only 63% postoperatively. Thirty-six patients had surgery: 6 (17%) were unresectable, 15 (52%) had R0 (≥ 1 mm) resections, 14 (48%) had R1 (< 1 mm) resections, and 1 patient did not have PDAC. Median progression-free survival was 12.3 months and median overall survival (OS) was 23.5 months: R0 patients had an OS of 35 months versus 25.6 months for R1 patients after surgery. Seven patients had not progressed after 43 months.

CONCLUSIONS

The GAP trial demonstrated that perioperative nab-gem was tolerable. Although the primary endpoint of an 85% R0 rate was not met, the R0 rate was similar to trials using a > 1 mm R0 resection definition, and survival rates were comparable with recent adjuvant studies.

The Impact of Positive Resection Margins on Survival and Recurrence Following Resection and Adjuvant Chemotherapy for Pancreatic Ductal Adenocarcinoma

OBJECTIVE AND BACKGROUND

Local and distant disease recurrence are frequently observed following pancreatic cancer resection, but an improved understanding of resection margin assessment is required to aid tailored therapies.

METHODS

Analyses were carried out to assess the association between clinical characteristics and margin involvement as well as the effects of individual margin involvement on site of recurrence and overall and recurrence-free survival using individual patient data from the European Study Group for Pancreatic Cancer (ESPAC)-3 randomized controlled trial.

RESULTS

There were 1151 patients, of whom 505 (43.9%) had an R1 resection. The median and 95% confidence interval (CI) overall survival was 24.9 (22.9-27.2) months for 646 (56.1%) patients with resection margin negative (R0 >1 mm) tumors, 25.4 (21.6-30.4) months for 146 (12.7%) patients with R1<1 mm positive resection margins, and 18.7 (17.2-21.1) months for 359 (31.2%) patients with R1-direct positive margins (P < 0.001). In multivariable analysis, overall R1-direct tumor margins, poor tumor differentiation, positive lymph node status, WHO performance status ≥1, maximum tumor size, and R1-direct posterior resection margin were all independently significantly associated with reduced overall and recurrence-free survival. Competing risks analysis showed that overall R1-direct positive resection margin status, positive lymph node status, WHO performance status 1, and R1-direct positive superior mesenteric/medial margin resection status were all significantly associated with local recurrence.

CONCLUSIONS

R1-direct resections were associated with significantly reduced overall and recurrence-free survival following pancreatic cancer resection. Resection margin involvement was also associated with an increased risk for local recurrence.

Pancreatoduodenectomy with colon resection for pancreatic cancer: a systematic review

BACKGROUND

Radical resection of advanced pancreatic cancer may occasionally require a simultaneous colon resection. The risks and benefits of this combined procedure are largely unknown. This systematic review aimed to assess short and long term outcome after pancreatoduodenectomy with colon resection (PD-colon) for pancreatic ductal adenocarcinoma (PDAC).

METHODS

A systematic literature search was performed in PubMed, Embase, and the Cochrane Library for studies published between 1994 and 2017 concerning PD-colon for PDAC.

RESULTS

After screening 2038 articles, 5 articles with a total of 181 patients undergoing PD-colon were eligible for inclusion. Included studies showed a relatively low risk of bias. The pooled complication rate was 73% (95% CI 61-84) including a pooled colonic anastomotic leak rate of 5.5%. Pooled mortality was 10% (95% CI 6-15). Pooled mean survival (data from 86 patients) was 18 months (95% CI 13-23) with pooled 3- and 5-year survival of 31% (95% CI 20-72) and 19% (95% CI 6-38).

CONCLUSION

Based on the available data, PD-colon for PDAC seems to be associated with an increased morbidity and mortality but with survival comparable with standard PD in selected patients. Future large series are needed to allow for better patient selection for PD-colon.

Revision of Surgical Margin under Frozen Section to Achieve R0 Status on Survival in Patients with Pancreatic Cancer

OBJECTIVE

The aim is to investigate whether additional resection based on intraoperative frozen section (FS) to a secondary R0(s) status are associated with different long-term survivals in pancreatic cancer patients, comparing to those with R1 or primary R0(p) status.

METHODS

A systematic literature search (PubMed, Embase, Science Citation Index, Springer-Link, and Cochrane Central Register of Controlled Trials) was performed to identify all studies published up to June 2017. Survivals of patients undergoing pancreatic surgery according to the results of FS and re-resection were pooled for analysis.

RESULTS

Five cohort studies were qualified for inclusion in this review with a total of 2980 patients. Long-term survival outcomes favored R0(p) resection as compared to R0(s) resection (HR = 1.58, 95%CI 1.24-2.01, P = 0.0002, I² = 58%). No significant difference was observed for patients with or without additional resection at the time of surgery when positive FS was detected (HR = 0.98, 95CI% 0.65-1.47, P = 0.91, I² = 81%).

CONCLUSIONS

The present study did not support the concept of achieving an R0 resection by intraoperative re-resection would benefit the patient's survival. R1 margin at the time of surgery is more like a marker of aggressive tumor biology. Future well-designed randomized controlled trials are needed to confirm the conclusion.

Neoadjuvant therapy affects margins and margins affect all: perioperative and survival outcomes in resected pancreatic adenocarcinoma

BACKGROUND

Resection margin status is an important prognostic factor in pancreatic cancer; however, the impact of positive resection margins in those who received neoadjuvant therapy remains unclear. The current study investigates the prognostic impact of resection margin status after neoadjuvant therapy and pancreaticoduodenectomy for patients with pancreatic adenocarcinoma.

METHODS

Patients who underwent pancreaticoduodenectomy for pancreatic adenocarcinoma between 2006 and 2013 were identified from the National Cancer Database. Multivariable logistic regression analysis was utilized to examine the predictive value of neoadjuvant therapy for resection margin status. Long-term outcomes were compared using a Cox proportional hazards model.

RESULTS

7917 patients were identified in total: 1077 (13.6%) and 6840 (86.4%) patients received neoadjuvant therapy and upfront surgery, respectively. Upfront surgery was independently predictive of a positive margin (25.7% vs. 17.7%; OR, 1.54) compared to neoadjuvant therapy. After receipt of neoadjuvant therapy, positive margins (median overall survival, 18.5 vs. 25.9 months; HR, 1.58) remained significantly associated with poor survival on multivariable analysis.

DISCUSSION

While neoadjuvant therapy is associated with decreased R1/R2-resection rates after pancreaticoduodenectomy, the poor prognostic impact of positive margins is not abrogated by neoadjuvant therapy, stressing the need for complete tumor clearance and postoperative treatment even after neoadjuvant therapy.

Proposal for a structured computed tomography report in the evaluation of pancreatic neoplasms based on expert opinions

Objective

To create a structured computed tomography (CT) report for the systematic evaluation of pancreatic ductal adenocarcinoma (PDAC), based on the opinions of clinicians and surgeons.

Materials and Methods

This was a prospective study in which we applied a 21-item questionnaire to experts in pancreatic diseases in order to create a model of a structured abdominal CT report. The questionnaire addressed the location and size of PDACs, as well as their effects on adjacent structures and on the vasculature, together with metastases. We used a Likert scale to determine which of those parameters should be included in the model.

Results

A total of 18 experts (12 surgeons and 6 clinicians) from 9 institutions completed the questionnaire. All of the experts agreed that the following (if present) should be described in the CT report on a PDAC: the degree of enhancement; the diameter and location of the lesion; pancreatic duct obstruction; biliary dilatation; pancreatic atrophy; liver metastases; peritoneal nodules; ascites; lymph node enlargement; and invasion of adjacent structures. More than 80% of the experts agreed that the report should also describe the relationship between the PDAC and the surrounding vasculature.

Conclusion

We have developed a template for a CT report on patients with PDAC, based on the opinions of experts involved in the treatment of such patients.

Systematic review on the impact of pancreatoduodenectomy on quality of life in patients with pancreatic cancer

BACKGROUND

Patients undergoing pancreatoduodenectomy for pancreatic cancer have a high risk of major postoperative complications and a low survival rate. Insight in the impact of pancreatoduodenectomy on quality of life (QoL) is therefore of great importance. The aim of this systematic review was to assess QoL after pancreatoduodenectomy for pancreatic cancer.

METHODS

A systematic review of the literature was performed according to the PRISMA guidelines. A systematic search of all the English literature available in PubMed and Medline was performed. All studies assessing QoL with validated questionnaires in pancreatic cancer patients undergoing pancreatoduodenectomy were included.

RESULTS

After screening a total of 788 articles, the full texts of 36 articles were assessed, and 17 articles were included. QoL of physical and social functioning domains decreased in the first 3 months after surgery. Recovery of physical and social functioning towards baseline values took place after 3-6 months. Pain, fatigue and diarrhoea scores deteriorated postoperatively, but eventually resolved after 3-6 months.

CONCLUSION

Pancreatoduodenectomy for malignant disease negatively influences QoL in the physical and social domains at short term. It will eventually recover to baseline values after 3-6 months. This information is valuable for counselling and expectation management of patients undergoing pancreatoduodenectomy.

Pathologic assessment of gastrointestinal tract and pancreatic carcinoma after neoadjuvant therapy

Neoadjuvant therapy is increasingly used to treat patients with a wide variety of malignancies. Histologic evaluation of treated specimens provides important prognostic information and may guide subsequent chemotherapy. Neoadjuvant therapy is commonly employed in the treatment of locally advanced rectal adenocarcinoma, hepatic colorectal metastases, esophageal/esophagogastric junction carcinoma, and pancreatic ductal adenocarcinoma. Numerous tumor regression schemes have been used in these tumors and standardized approaches to evaluate these specimens are needed. In this review, the various tumor regression scoring systems that have been used in these organs are described and their associations with clinical outcomes are discussed. Recommendations regarding how to handle and report the histologic findings in these resections specimens are provided.

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.

Minimally Invasive Versus Open Pancreatoduodenectomy: Systematic Review and Meta-analysis of Comparative Cohort and Registry Studies

OBJECTIVE

This study aimed to appraise and to evaluate the current evidence on minimally invasive pancreatoduodenectomy (MIPD) versus open pancreatoduodenectomy only in comparative cohort and registry studies.

BACKGROUND

Outcomes after MIPD seem promising, but most data come from single-center, noncomparative series.

METHODS

Comparative cohort and registry studies on MIPD versus open pancreatoduodenectomy published before August 23, 2015 were identified systematically and meta-analyses were performed. Primary endpoints were mortality and International Study Group on Pancreatic Fistula grade B/C postoperative pancreatic fistula (POPF).

RESULTS

After screening 2293 studies, 19 comparative cohort studies (1833 patients) with moderate methodological quality and 2 original registry studies (19,996 patients) were included. For cohort studies, the median annual hospital MIPD volume was 14. Selection bias was present for cancer diagnosis. No differences were found in mortality [odds ratio (OR) = 1.1, 95% confidence interval (CI) = 0.6-1.9] or POPF [(OR) = 1.0, 95% CI = 0.8 to 1.3]. Publication bias was present for POPF. MIPD was associated with prolonged operative times [weighted mean difference (WMD) = 74 minutes, 95% CI = 29-118], but lower intraoperative blood loss (WMD = -385 mL, 95% CI = -616 to -154), less delayed gastric emptying (OR = 0.6, 95% = CI 0.5-0.8), and shorter hospital stay (WMD = -3 days, 95% CI = -5 to -2). For registry studies, the median annual hospital MIPD volume was 2.5. Mortality after MIPD was increased in low-volume hospitals (7.5% vs 3.4%; P = 0.003).

CONCLUSIONS

Outcomes after MIPD seem promising in comparative cohort studies, despite the presence of bias, whereas registry studies report higher mortality in low-volume centers. The introduction of MIPD should be closely monitored and probably done only within structured training programs in high-volume centers.

Sulfonylureas (not metformin) improve survival of patients with diabetes and resectable pancreatic adenocarcinoma

Patients with pancreatic adenocarcinoma have an increased propensity for diabetes. Recent studies suggest patients with diabetes and pancreatic adenocarcinoma treated with metformin have increased survival. This study was undertaken to determine whether metformin use is associated with increased survival in patients with pancreatic adenocarcinoma.

The Impact of New Technologic and Molecular Advances in the Daily Practice of Gastrointestinal and Hepatobiliary Pathology

The practice of anatomic pathology, and of gastrointestinal pathology in particular, has been dramatically transformed in the past decade. In addition to the multitude of diseases, syndromes, and clinical entities encountered in daily clinical practice, the increasing integration of new technologic and molecular advances into the field of gastroenterology is occurring at a fast pace. Application of these advances has challenged pathologists to correlate newer methodologies with existing morphologic criteria, which in many instances still provide the gold standard for diagnosis. This review describes the impact of new technologic and molecular advances on the daily practice of gastrointestinal and hepatobiliary pathology. We discuss new drugs that can affect the gastrointestinal tract and liver, new endoluminal techniques, new molecular tests that are often performed reflexively, new imaging techniques for evaluating hepatocellular carcinoma, and modified approaches to the gross and histologic assessment of tissues that have been exposed to neoadjuvant therapies.

Frozen section analysis of the pancreatic margin during pancreaticoduodenectomy for cancer: Does extending the resection to obtain a secondary R0 provide a survival benefit? Results of a systematic review

BACKGROUND

During pancreaticoduodenectomy, frozen section pancreatic margin analysis permits to extend the resection in case of a positive margin, to achieve R0 margin. We aim to assess if patients having an R0 margin following the extension of the pancreatectomy after a positive frozen section (secondary R0) have different survival compared to those with R1 resection or primary R0 resection.

METHODS

A systematic search was performed to identify all studies published up to March 2016 analyzing the survival of patients undergoing pancreaticoduodenectomy according to the results of frozen section pancreatic margin examination. Clinical effectiveness was synthetized through a narrative review with full tabulation of results.

RESULTS

Four studies published between 2010 and 2014 were retrieved, including 2580 patients. A primary R0 resection was obtained in a percentage of patients ranging from 36.2% to 85.5%, whereas secondary R0 in 9.4%-57.8% of cases and R1 in 5.1%-9.2%. Median survival ranged from 19 to 29 months in R0 patients, from 11.9 to 18 months in secondary R0, and from 12 to 23 months in R1 patients. None of the study demonstrated a survival benefit of extending the resection to obtain a secondary R0 pancreatic margin.

CONCLUSIONS

All the studies were concordant, and failed to demonstrate the survival benefit of additional pancreatic resection to obtain a secondary R0. However, inadequate surgery should not be advocated. This review suggests that re-resection of the pancreatic margin may have limited impact on patients' survival.

A Graded Evaluation of Outcomes Following Pancreaticoduodenectomy with Major Vascular Resection in Pancreatic Cancer

Previous studies examining short- and long-term outcomes of pancreaticoduodenectomy with vascular resection for pancreatic adenocarcinoma have not graded perioperative complication severity. These studies may provide incomplete assessments of the efficacy of vascular resection. In the current study, we evaluated 36 patients who had pancreaticoduodenectomy with major vascular resection. These were matched 1:3 by tumor stage and age to patients who had pancreaticoduodenectomy without vascular resection. Charts were reviewed to identify all complications and 90-day readmissions. Complications were graded as either severe or minor adverse postoperative outcomes, taking into account the total length of stay. There were no statistical differences in patient demographics, comorbidities, or symptoms between the groups. Patients who had vascular resection had significantly increased rates of severe adverse postoperative outcomes, readmissions, lengths of hospital stay, as well as higher hospital costs. Hypoalbuminemia and major vascular resection were independent predictors of severe adverse postoperative outcomes. On multivariate Cox-regression survival analysis, patients who had vascular resection had decreased recurrence-free (12 vs. 17 months) and overall (17 vs. 29 months) survival. Major vascular resection was a predictor of mortality, may be an independent prognostic factor for survival, and may warrant incorporation into future staging systems.

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.

Frozen Section Interpretation of Pancreatic Margins: Subspecialized Gastrointestinal Pathologists Versus General Pathologists

Intraoperative assessment of pancreatic parenchymal margin during pancreatectomies is challenging and misinterpretation by the pathologist is a cause of incorrect frozen section (FS) diagnosis. Although the current literature supports that pancreatic margin FS diagnosis and its accuracy has no impact on the patient outcome for pancreatic ductal adenocarcinoma (PDAC) patients and reexcision in an attempt to achieve a negative intraoperative pancreatic margin after positive FS is not associated with increased overall survival; still it remains a routine practice in many institutions. To this end, we sought to assess the interobserver variation and accuracy of FS diagnosis between subspecialized gastrointestinal/pancreatobiliary (GI) and general pathologists. Seventy seven consecutive pancreatic parenchymal margin FSs performed on pancreatectomies for PDAC from 2010 to 2013 were retrieved at our institution. These were retrospectively evaluated by 2 GI and 2 general pathologists independently without knowledge of the original FS diagnosis or the final diagnosis. The specificity, sensitivity, positive predictive value, negative predictive value, and accuracy of GI versus general pathologist was 97.8% versus 87.5%, 61.1% versus 66.7%, 78.6% versus 41.4%, 95% versus 95.2%, and 93.5% versus 85.1%, respectively. The interobserver agreement between GI and general pathologists was fair (κ = .337, P < .001). The interobserver agreement between 2 GI pathologists was fair (κ = .373, P = .0005) and between 2 general pathologists was slight (κ = .195, P = .042). Although overall accuracy of subspecialized GI pathologists was higher than that of general pathologists, none had an accuracy of 100%. Our study reaffirms the challenging nature of these FSs.

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.

Artery first approach to pancreatoduodenectomy: current status

BACKGROUND

The need for an early determination of resectability and before an irreversible step is taken during pancreatoduodenectomy promoted the development of an 'artery first approach' (AFA). The aim of this study was to review the current evidence related to this approach, with particular reference to margins and survival.

METHODS

An electronic search was performed in MEDLINE, EMBASE and PubMed databases from 1960 to 2015 using both subject headings (MeSH) and truncated word searches to identify all published related articles to this topic.

RESULTS

Six different AFAs have been published. Four studies evaluated the impact of AFA on perioperative outcomes and survival. Three studies showed no difference in the perioperative outcomes, margin status, lymph node yield and survival while one study showed improved margin status and survival comparing AFA with standard resection.

CONCLUSION

The current evidence regarding the benefits of AFA in relation to decreasing margin positivity or increasing survival is sparse. Further larger studies and randomized controlled trails are needed to ascertain the benefits of AFA.

Predicting early mortality in resectable pancreatic adenocarcinoma: A cohort study

BACKGROUND

Survival after surgical resection for pancreatic cancer remains poor. A subgroup of patients die early (<6 months), and understanding factors associated with early mortality may help to identify high-risk patients. The Khorana score has been shown to be associated with early mortality for patients with solid tumors. In the current study, the authors evaluated the role of this score and other prognostic variables in this setting.

METHODS

The current study was a cohort study of patients who underwent surgical resection for pancreatic cancer from January 2006 through June 2013. Baseline (diagnosis ±30 days) parameters were used to define patients as high risk (Khorana score ≥3). Statistically significant univariable associations and a priori prognostic variables were tested in multivariable models; adjusted hazard ratios (HR) were calculated.

RESULTS

The study population comprised 334 patients. The median age was 67 years, 50% of the study population was female, and 86% of the patients were white. The pancreatic head was the primary tumor site for 73% of patients; 67% of tumors were T3 and 63% were N1. The median Khorana score was 2; 152 patients (47%) were determined to be high risk. Adjunctive treatment included chemotherapy (70%) and radiotherapy (40%). The postoperative (30-day) mortality rate was 0.9%. The 6-month mortality rate for the entire cohort was 9.4%, with significantly higher rates observed for high-risk patients (13.4% vs 5.6%; P = .02). On multivariable analyses (examining a total of 326 patients), the Khorana score (HR for high risk, 2.31; P = .039) and elevated blood urea nitrogen (HR, 4.34; P<.001) were associated with early mortality.

CONCLUSIONS

Patients at high risk of early mortality after surgical resection of pancreatic adenocarcinoma can be identified using simple baseline clinical and laboratory parameters. Future studies should address preoperative interventions in these patients at high risk of early mortality.