Resection margin clearance in pancreatic cancer after implementation of the Leeds Pathology Protocol (LEEPP): clinically relevant or just academic?

Resection Margin Status and Long-Term Outcomes after Pancreaticoduodenectomy for Ductal Adenocarcinoma: A Tertiary Referral Center Analysis

The influencing role of resection margin (R) status on long-term outcomes, namely overall (OS) and disease-free survival (DFS), after pancreaticoduodenectomy (PD) for pancreatic ductal adenocarcinoma (PDAC) is not still clear. The aim of this study is to evaluate the prognostic impact of R status after PD and to define tumor characteristics associated with a positive resection margin (R1). All PDs for PDAC performed between 2012 and 2023 were retrospectively enrolled. The effect of R status, patient clinico-demographic features, and tumor features on OS and DFS were assessed. One-hundred and sixty-seven patients who underwent PD for PDAC were included in the study. R0 was achieved in 105 cases (62.8%), while R1 was evidenced in 62 patients (37.1%). R1 was associated with a decreased OS (23 (13-38) months) as compared to R0 (36 (21-53) months) (p = 0.003). Similarly, DFS was shorter in R1 patients (10 (6-25) months) as compared to the R0 cohort (18 (9-70) months) (p = 0.004), with a consequent higher recurrence rate in cases of R1 (74.2% vs. 64.8% in the R0 group; p = 0.04). In the multivariate analysis, R1 and positive lymph nodes (N+) were the only independent influencing factors for OS (OR: 1.6; 95% CI: 1-2.5; p = 0.03 and OR: 1.7; 95% CI: 1-2.8; p = 0.04) and DFS (OR: 1.5; 95% CI: 1-2.1; p = 0.04 and OR: 1.8; 95% CI: 1.1-2.7; p = 0.009). Among 111 patients with N+ disease, R1 was associated with a significantly decreased DFS (10 (8-11) months) as compared to R0N+ patients (16 (11-21) months) (p = 0.05). In conclusion, the achievement of a negative resection margin is associated with survival benefits, particularly in cases of N1 disease. In addition, R0 was recognized as an independent prognostic feature for both OS and DFS. This further outlines the relevant role of radical surgery on long-term outcomes.

The impact of vascular margin invasion on local recurrence after pancreatoduodenectomy in pancreatic adenocarcinoma

PURPOSE

Pancreatic ductal adenocarcinoma (PADC) still has nowadays a very impaired long-term survival. Most studies are focused on overall survival; however, local recurrence occurs about up to 50% of cases and seems to be highly related with margin resection status. We aim to analyze the impact of vascular resection margins on local recurrence (LR) and to assess its impact on overall and disease-free survival.

METHODS

Eighty out of 191 patients who underwent pancreatoduodenectomy in a university hospital between 2006 and 2021 with PDAC diagnosis were analyzed and vascular margin status specifically addressed. Univariate and multivariate were performed. Time to LR was compared by using the Kaplan-Meier method and prognostic factors assessed using Cox regression hazards model.

RESULTS

LR appeared in 10 (50%) of the overall R1 resections in the venous margin and 9 (60%) in the arterial one. Time to LR was significantly shorter when any margin was overall affected (23.2 vs 44.7 months, p = 0.01) and specifically in the arterial margin involvement (13.7 vs 32.1 months, p = 0.009). Overall R1 resections (HR 2.61, p = 0.013) and a positive arterial margin (HR 2.84, p = 0.012) were associated with local recurrence on univariate analysis, whereas arterial positive margin remained significant on multivariate analysis (HR 2.70, p = 0.031).

CONCLUSIONS

Arterial margin invasion is correlated in our cohort with local recurrence. Given the limited ability to modify this margin intraoperatively, preoperative therapies should be considered to improve local margin clearance.

What are the true benefits of robotic pancreaticoduodenectomy for patients with pancreatic cancer?

INTRODUCTION

Pancreatic ductal adenocarcinoma (PDAC) is a devastating disease, and multimodal treatment including high-quality surgery can improve survival outcomes. Pancreaticoduodenectomy (PD) has evolved with minimally invasive approaches including the implementation of robotic PD (RPD). In this special report, we review the literature whilst evaluating the 'true benefits' of RPD compared to open approach for the treatment of PDAC.

AREAS COVERED

We have performed a mini-review of studies assessing PD approaches and compared intraoperative characteristics, perioperative outcomes, post-operative complications and oncological outcomes.

EXPERT OPINION

RPD was associated with similar or longer operative times, and reduced intra-operative blood loss. Perioperative pain scores were significantly lower with shorter lengths of stay with the robotic approach. With regards to post-operative complications, post-operative pancreatic fistula rates were similar, with lower rates of clinically relevant fistulas after RPD. Oncological outcomes were comparable or superior in terms of margin status, lymph node harvest, time to chemotherapy and survival between RPD and OPD. In conclusion, RPD allows safe implementation of minimally invasive PD. The current literature shows that RPD is either equivalent, or superior in certain aspects to OPD. Once more centers gain sufficient experience, RPD is likely to demonstrate clear superiority over alternative approaches.

Prognostic value of margin clearance in total and distal pancreatectomy specimens with pancreatic ductal adenocarcinoma in a Danish population-based nationwide study

BACKGROUND

The prognostic role of resection margin status following total (TP) and distal (DP) pancreatectomy for pancreatic ductal adenocarcinoma (PDAC) is insufficiently evaluated. In Denmark, pancreatic surgery, including the postoperative pathological examination of the resection specimens, is confined to four centres, all reporting to the Danish Pancreatic Cancer Database (DPCD). In this Danish population-based nationwide study on TP and DP for PDAC from 2015-2019, based on data from DPCD, we evaluated whether there is a prognostically relevant minimum margin clearance definition and whether certain margins hold independent prognostic information.

METHODS

Clinical and pathological data were retrieved from DPCD and supplemented by review of pathology reports and re-microscopy, if needed. One of the study pathologists performed all re-microscopy. The prognostic significance of margin status was evaluated by dichotomisation of the TP cohort (n = 101) and the DP cohort (n = 90) into involved and uninvolved groups, using different clearance definitions (0.5 - ≥3.0 mm).

RESULTS

Following TP, direct involvement of the superior mesenteric artery (SMA) margin had independent prognostic value. When using a clearance definition of ≥ 0.5 or ≥ 1.5 mm for SMA, median survival for R0 versus R1 was 19 (95% CI 14-26) versus 10 (95% CI 5-20) months (p = 0.010), and 21 (95% CI 15-30) versus 10 (95% CI 8-19) months (p = 0.011), respectively. Overall margin status was not of significant prognostic importance following neither DP nor TP.

CONCLUSION

In this Danish population-based nationwide study, SMA margin involvement was a significant isolated prognostic factor following TP, whereas combined assessment of all circumferential margins did not hold statistically significant prognostic information. Following DP, resection margin status did not affect survival.

Prognostic importance of margin clearance in ampullary adenocarcinoma following pancreaticoduodenectomy in a Danish population-based nationwide study

BACKGROUND

In this Danish nationwide population-based study, we evaluated the prognostically relevant minimum tumour-free margin width following pancreaticoduodenectomy (PD) for ampullary adenocarcinoma (AAC) and evaluated whether certain margins hold independent prognostic information.

METHODS

We included 128 patients who underwent PD for AAC from 2015 to 2019. Clinical and pathological data including well-known prognostic factors were retrieved from the Danish Pancreatic Cancer Database. Missing data were obtained by review of pathology reports and re-microscopy of resection specimens. All PD specimens were examined using a standardised pathological protocol including multicolour inking, axial slicing and exact reporting of margin widths. The cohort was dichotomised into involved and uninvolved groups, using different margin clearance definitions (0.5-≥3.0 mm).

RESULTS

Following PD for AAC, margin clearance of ≥1 mm was independently associated with improved chance of survival compared with <1 mm (HR: 0.30, 95 % CI: 0.14-0.64 (p = 0.002)). Posterior and anterior margin widths were narrower compared with superior mesenteric artery and vein margins. Posterior margin and anterior surface had isolated prognostic significance in multivariable analysis.

CONCLUSION

Following PD for AAC, margin clearance of at least 1 mm is independently associated with improved survival. Our data further indicate that anterior surface and posterior margin hold particular prognostic value.

Prognostic effect of CD73 in pancreatic ductal adenocarcinoma for disease-free survival after radical surgery

PURPOSE

Pancreatic ductal adenocarcinoma (PDAC) is a lethal disease with a high potency of metastasis or recurrence after radical resection. Effective predictors for metastasis and recurrence postoperatively were dominant for the development of systemic adjuvant treatment regimens. The ATP hydrolase correlated gene CD73 was described as a promoter in tumor growth and immune escape of PDAC. However, there lacked research focused on the role of CD73 in PDAC metastasis. This study aimed to investigate the expression of CD73 in PDAC patients with different outcomes as well as the prognostic effect of CD73 for disease-free survival (DFS).

METHODS

The expression level of CD73 in cancerous samples from 301 PDAC patients was evaluated by immunohistochemistry (IHC) and translated into a histochemistry score (H-score) by the HALO analysis system. Then, the CD73 H-score was involved in multivariate Cox regression along with other clinicopathological characteristics to find independent prognostic factors for DFS. Finally, a nomogram was constructed based on those independent prognostic factors for DFS prediction.

RESULTS

Higher CD73 expression was found in PDAC patients with tumor metastasis postoperatively. Meanwhile, higher CD73 expressions were also investigated in PDAC patients diagnosed with advanced N stage and T stage. Furthermore, CD73 H-score along with tumor margin status, CA19-9, 8th N stage, and adjuvant chemotherapy was indicated as independent prognostic factors for DFS in PDAC patients. The nomogram based on these factors predicted DFS in a good manner.

CONCLUSION

CD73 was associated with PDAC metastasis and served as an effective prognostic factor for DFS in PDAC patients after radical surgery.

Non-invasive preoperative prediction of Edmondson-Steiner grade of hepatocellular carcinoma based on contrast-enhanced ultrasound using ensemble learning

Purpose

This study aimed to explore the clinical value of non-invasive preoperative Edmondson-Steiner grade of hepatocellular carcinoma (HCC) using contrast-enhanced ultrasound (CEUS).

Methods

212 cases of HCCs were retrospectively included, including 83 cases of high-grade HCCs and 129 cases of low-grade HCCs. Three representative CEUS images were selected from the arterial phase, portal vein phase, and delayed phase and stored in a 3-dimensional array. ITK-SNAP was used to segment the tumor lesions manually. The Radiomics method was conducted to extract high-dimensional features on these contrast-enhanced ultrasound images. Then the independent sample T-test and the Least Absolute Shrinkage and Selection Operator (LASSO) were employed to reduce the feature dimensions. The optimized features were modeled by a classifier based on ensemble learning, and the Edmondson Steiner grading was predicted in an independent testing set using this model.

Results

A total of 1338 features were extracted from the 3D images. After the dimension reduction, 10 features were finally selected to establish the model. In the independent testing set, the integrated model performed best, with an AUC of 0.931.

Conclusion

This study proposed an Edmondson-Steiner grading method for HCC with CEUS. The method has good classification performance on independent testing sets, which can provide quantitative analysis support for clinical decision-making.

WNT5A: a double-edged sword in colorectal cancer progression

The Wnt signaling pathway is known to play a crucial role in cancer, and WNT5A is a member of this pathway that binds to the Frizzled (FZD) and Receptor Tyrosine Kinase-Like Orphan Receptor (ROR) family members to activate non-canonical Wnt signaling pathways. The WNT5A pathway is involved in various cellular processes, such as proliferation, differentiation, migration, adhesion, and polarization. In the case of colorectal cancer (CRC), abnormal activation or inhibition of WNT5A signaling can lead to both oncogenic and antitumor effects. Moreover, WNT5A is associated with inflammation, metastasis, and altered metabolism in cancer cells. This article aims to discuss the molecular mechanisms and dual roles of WNT5A in CRC.

Prognostic significance of margin clearance in pancreaticoduodenectomy specimens with pancreatic ductal adenocarcinoma in a Danish population-based nationwide study

BACKGROUND

In this nationwide population-based cohort study, we investigated the overall minimum margin width that is independently associated with improved survival following pancreaticoduodenectomy (PD) for pancreatic ductal adenocarcinoma (PDAC) and evaluated whether certain margins or surfaces hold independent prognostic significance.

METHODS

Data from 367 patients who underwent PD for PDAC in the period 2015-2019 were retrieved from the Danish Pancreatic Cancer Database. Missing data were obtained by review of pathology reports and re-microscopy of resection specimens. Surgical specimens were evaluated using a standardised pathological protocol involving multicolour inking, axial slicing and exact reporting of circumferential margin clearances in 0.5 mm increments.

RESULTS

When categorised according to margin widths of <0.5, <1.0, <1.5, <2.0, <2.5 and <3.0 mm, R1 resections were detected in 34%, 57%, 75%, 78%, 86% and 87% of cases, respectively. In multivariable analyses, an overall margin clearance of ≥1.5 mm was associated with improved survival compared with a clearance of <1.5 mm (HR 0.70 95% CI 0.51-0.97 (p = 0.031)). When evaluating the margins separately, no margin had independent prognostic significance.

CONCLUSION

Margin clearance of at least 1.5 mm was independently associated with improved survival following PD for PDAC.

The Impact of Involved Resection Margin on Recurrence and Survival After Pancreaticoduodenectomy for Periampullary Carcinoma, with Emphasis on Pancreatic Head Carcinoma

BACKGROUND

The supposed adverse effect of involved resection margin during pancreaticoduodenectomy (PD) for periampullary carcinoma or pancreatic head carcinoma (CaP) on long-term oncological outcomes is still inconclusive.

METHODS

This is a retrospective study on periampullary carcinoma undergoing PD. Patients with R0 (margin clear) resection were compared to patients with R1 (microscopically directly involved margin) resection. Patients with gross involved margin (R2 resection) were excluded. Long-term oncological outcomes measured included incidence and site of recurrent disease, overall survival (OS) and disease-free survival (DFS). A subgroup analysis was made on patients with CaP.

RESULTS

Between January 2003 and December 2019, 203 PD were identified for present study. The incidence of R1 resection was common (12% in periampullary carcinoma and 20% in CaP). In periampullary carcinoma, R1 resection had greater proportion of CaP, lesser proportion of carcinoma of ampulla (CaA), more perineural invasion, more lymph node (LN) metastasis. R1 group had a shorter OS and DFS, but no difference in the incidence and site of recurrent disease. In the subgroup of CaP (91 patients), R1 group did not differ from R0 group except for more LN metastasis. There was no difference in incidence and site of recurrent disease, OS and DFS. On multivariable analysis, R1 resection was not an independent factor for OS and DFS for periampullary carcinoma or for CaP only.

CONCLUSION

Involved resection margin was not uncommon. It was not associated with higher incidence of recurrent disease including local recurrence, and was not an independent prognosticator for OS and DFS.

The impact of resection margin distance on survival and recurrence in pancreatic ductal adenocarcinoma in a retrospective cohort analysis

BACKGROUND

The prognostic effect of resection margin status following pancreatoduodenectomy for pancreatic ductal adenocarcinoma (PDAC) remains controversial, even with the implementation of standardized pathological assessment. We therefore investigated the impact of resection margin (RM) status and RM distance in curative resected PDAC on overall survival (OS), disease-free survival (DFS) and recurrence.

METHOD

108 patients were retrieved from a prospectively maintained database of a certified pancreatic cancer center. Distribution and relationships between circumferential resection margin (CRM) involvement (CRM≤1mm; CRM>1mm; CRM≥2mm) and their prognostic impact on OS and DFS were assessed using Kaplan-Meier statistics and the Log-Rank test. Multivariate logistic regression was used explain the development of a recurrence 12 months after surgery.

RESULTS

63 out of 108 patients had medial RM and 32 posterior RM involvement. There was no significant difference in OS and DFS between CRM≤1mm and CRM>1mm resections. Clearance at the medial margin of ≥2mm had an impact on OS and DFS, (RM≥2mm vs. RM<2mm: median OS 29.8 vs 16.8 months, median DFS 19.6 vs. 10.3 months). Multivariate analysis demonstrated that age, medial RM ≥2mm, lymph node status and chemotherapy were prognostic factors for OS and DFS. Posterior RM had no influence on OS or DFS.

CONCLUSION

Not all RM seem to have the same impact on OS and DFS, and a clearance of 1mm for definition of a negative RM (i.e. CRM>1mm) seems not sufficient. Future studies should include more patients to stratify for potential confounders we could not account for.

TRIAL REGISTRATION

This study was registered with the German Clinical Trials Registry (reference number DRKS0017425).

Risk factors of positive resection margin differ in pancreaticoduodenectomy and distal pancreatosplenectomy for pancreatic ductal adenocarcinoma undergoing upfront surgery

OBJECTIVE

Positive resection margin indicates worse prognosis. The present study identified the independent risk factors of R1 resection in pancreaticoduodenectomy (PD) and distal pancreatosplenectomy (DP) for patients with pancreatic ductal adenocarcinoma (PDAC).

METHOD

Consecutive patients who were operated from 1st December 2017 to 30th December 2018 were analyzed retrospectively. A standardized pathological examination with digital whole-mount slide images (DWMSIs) was utilized for evaluation of resection margin status. R1 was defined as microscopic tumor infiltration within 1 mm to the resection margin. The potential risk factors of R1 resection for PD and DP were analyzed separately by univariate and multivariate logistic regression analyses.

RESULTS

For the 192 patients who underwent PD, and the 87 patients who underwent DP, the R1 resection rates were 31.8% and 35.6%, respectively. Univariate analysis on risk factors of R1 resection for PD were tumor location, lymphovascular invasion, N staging, and TNM staging; while those for DP were T staging and TNM staging. Multivariate logistic regression analysis showed the location of tumor in the neck and uncinate process, and N1/2 staging were independent risk factors of R1 resection for PD; while those for DP were T3 staging.

CONCLUSIONS

The clarification of the risk factors of R1 resection might clearly make surgeons take reasonable decisions on surgical strategies for different surgical procedures in patients with PDAC, so as to obtain the first attempt of R0 resection.

The Future Perspectives of Redefining the Resection Margin Status in Different Cancers of Pancreas

Background: The interest towards the assessment of circumferential resection margins(CRM) in pancreatic cancers has been evolving over last years. Whilst several studies investigated the influence of R1-resections on survival, not many studies evaluated the prognostic value of each resection margin. In this study, we examined the different resection margins to better understand their prognostic implications on overall survival. Methods: This prospective study included a cohort of patients who had pancreaticoduodenectomy for cancer purposes at our institution from 2008 till 2013. Median follow-up was 6 years. Involved margins in R1-resections were further classified into anatomical margins (anterior, posterior and circumferential margins) and surgical margins (vascular/medial margins and transection margins). Overall survival was assessed for each specific resection margin. Results: 134 patients were included with median age 66 years. R1-resection was done in 54% of patients(n=72/134). Median survival of R0-resection group was 6.3 years, compared to 1.9 years for R1-resection group(p-value 0.001). Vascular (surgical) margins had the lowest survival rate (1.7years) compared to anatomical margins (anterior, posterior and circumferential margins) with 3.6, 2.2 and 2.1 years respectively (p-value 0.02). On multivariate analysis; lymph node involvement and vascular resection were the only factors to correlate significantly with poor survival. Conclusion: Whilst the new pathological protocols advised to perform rigorous margin assessment of CRM, the prognostic value of each resection margin is still unclear. This study  showed variation of survival across different resection margins with inferiority towards vascular (surgical) margins. This supported the need of redefining R1-margins in the future pathological classifications according to their different prognostic impacts.

Prognostic relevance of the revised R status definition in pancreatic cancer: meta-analysis

BACKGROUND

The prognostic impact of margin status is reported with conflicting results after pancreatic cancer resection. While some studies validated an uninvolved resection margin (R0) 1 mm or more of tumour clearance, others have failed to show benefit. This systematic review and meta-analysis aimed to investigate the effects of margin definitions on median overall survival (OS).

METHODS

MEDLINE, Web of Science, and the Cochrane Central Register of Controlled Trials were searched for studies reporting associations between resection margins and OS between 2010 and 2021. Data regarding margin status (R0 circumferential resection margin (CRM) negative (CRM-), R0 CRM positive (CRM+), R0 direct, and R1 and OS were extracted. Hazard ratios (HRs) were pooled with a random-effects model. The risk of bias was evaluated with the Quality in Prognosis Studies (QUIPS) tool.

RESULTS

The full texts of 774 studies were screened. In total, 21 studies compromising 6056 patients were included in the final synthesis. In total, 188 (24 per cent) studies were excluded due to missing margin definitions. The R0 (CRM+) rate was 50 per cent (95 per cent confidence interval (c.i.) 0.40 to 0.61) and the R0 (CRM-) rate was 38 per cent (95 per cent c.i. 0.29 to 0.47). R0 (CRM-) resection was independently associated with improved OS compared to combined R1 and R0 (CRM+; HR 1.36, 95 per cent c.i. 1.23 to 1.56).

CONCLUSION

The revised R status was confirmed as an independent prognosticator compared to combined R0 (CRM+) and R1. The limited number of studies, non-standardized pathology protocols, and the varying number of margins assessed hamper comparability.

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.

Comparative Recurrence Analysis of Pancreatic Adenocarcinoma after Resection

Purpose

The relation between tumor sites of pancreatic ductal adenocarcinoma (PDAC) and recurrence was not fully investigated before. We aimed to describe the differences of recurrent patterns in PDAC of head and body/tail after curative surgery.

Methods

The recurrent patterns of PDAC were compared and the associations with clinical characteristics were analyzed in these patients. Prognostic factors of overall survival (OS) and progression-free survival (PFS) were analyzed and validated. Predictive systems were constructed and measured by the area under the AUC curve and concordance index (C-index).

Results

A total of 302 PDAC patients were included in this study, including 247 patients with PDAC of head and another 55 patients with PDAC of body/tail. Patients who developed tumor recurrence within 24 months after resection had significantly shorter OS in both groups. Liver metastasis occupied most of the tumor progressions and diminished while local recurrence increased gradually over time. The variation trends were similar for patients in both groups while these changes were more pronounced for patients in the head group. Local recurrence and liver-only metastasis seemed to indicate a better OS. Furthermore, predictive systems for OS and PFS prediction based on independent risk factors were established and showed significant higher values of AUC and C-indexes compared with the TNM stage system.

Conclusions

Different characteristics of progressions for PDAC of head and body/tail suggested biological heterogeneity. The exploration of these variations helps to provide personalized management of recurrence in PDAC.

Prognostic Impact of Resection Margin Status in Distal Pancreatectomy for Ductal Adenocarcinoma

Background

Resection margin status is considered one of the few surgeon-controlled parameters affecting prognosis in pancreatic ductal adenocarcinoma (PDAC). While studies mostly focus on resection margins in pancreatoduodenectomy, little is known about their role in distal pancreatectomy (DP). This study aimed to investigate resection margins in DP for PDAC.

Methods

Patients who underwent DP for PDAC between October 2004 and February 2020 were included (n = 124). Resection margins and associated parameters were studied in two consecutive time periods during which different pathology examination protocols were used: non-standardized (period 1: 2004–2014) and standardized (period 2: 2015–2020). Microscopic margin involvement (R1) was defined as ≤1 mm clearance.

Results

Laparoscopic and open resections were performed in 117 (94.4%) and 7 (5.6%) patients, respectively. The R1 rate for the entire cohort was 73.4%, increasing from 60.4% in period 1 to 83.1% in period 2 (p = 0.005). A significantly higher R1 rate was observed for the posterior margin (35.8 vs. 70.4%, p < 0.001) and anterior pancreatic surface (based on a 0 mm clearance; 18.9 vs. 35.4%, p = 0.045). Pathology examination period, poorly differentiated PDAC, and vascular invasion were associated with R1 in the multivariable model. Extended DP, positive anterior pancreatic surface, lymph node ratio, perineural invasion, and adjuvant chemotherapy, but not R1, were significant prognostic factors for overall survival in the entire cohort.

Conclusions

Pathology examination is a key determinant of resection margin status following DP for PDAC. A high R1 rate is to be expected when pathology examination is meticulous and standardized. Involvement of the anterior pancreatic surface affects prognosis.

Supplementary Information

The online version contains supplementary material available at 10.1245/s10434-021-10464-6.

Impact of Neoadjuvant Therapy on Survival Following Margin-Positive Resection for Pancreatic Cancer

INTRODUCTION

A positive microscopic margin (R1) following resection of pancreatic ductal adenocarcinoma (PDAC) can occur in up to 80% of patients and is associated with reduced survival and increased recurrence. Our aim was to characterize the impact of neoadjuvant therapy (NAT) on survival and recurrence in patients with PDAC following an R1 resection.

METHODS

A retrospective analysis of patients with PDAC who underwent pancreatectomy from 2008 to 2017 was performed. Patients were staged according to the American Joint Committee on Cancer 8th edition and stratified based on resection margin (R0 vs. R1) and treatment sequence (NAT vs. surgery first [SF]). Conditional survival analysis was performed using Cox regression and inverse probability weighted estimates.

RESULTS

Among 580 patients, 59% received NAT and 41% underwent SF. On final pathology, the NAT cohort had smaller tumors and less lymph node (LN) positivity (p < 0.05). NAT was not associated with an R1 resection (50%, p = 0.653). Compared with the R1 cohort, the R0 cohort had a higher median overall survival (OS; 39.6 vs. 22.8 months; hazard ratio [HR] 1.6, p < 0.001) and disease-free survival (DFS; 19 vs. 13 months; HR 1.35, p = 0.004). After risk adjustment, NAT was not associated with OS, regardless of margin status (R0, 95% confidence interval [CI] (-)7.31-27.07, p = 0.26; or R1, 95% CI (-)36.99-15.25, p = 0.42). However, NAT was associated with improved DFS in the R1 cohort (95% CI 1.79-11.91, p = 0.008) but not in the R0 cohort (95% CI (-)11.22-10.54, p = 0.95).

CONCLUSION

An R0 resection remains an important determinant of overall and disease-free survival, even when NAT is administered. For patients with an R1 resection, receipt of NAT may prolong DFS.

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.

Prognostic impact of conservative surgery for pancreatic IPMNs

BACKGROUND

The extent of pancreatic resection for intraductal papillary mucinous neoplasms (IPMNs) remains an unresolved issue. The study aims at analyzing the prognostic impact of conservative surgery (CS) i.e. of pancreatoduodenectomy or distal pancreatectomy, versus total pancreatectomy (TP), for pancreatic IPMNs.

METHODS

We retrospectively analyzed and compared data of patients who had undergone pancreatic resection for IPMNs at our center between November 2007 and April 2019. Patients were divided into two main groups based on the extent of surgery: TP-group and CS-group. Subsequently, the perioperative and the long-term outcomes were compared. Moreover, a sub-group analysis of patients with IPMN alone and patients with malignant IPMN, based on preoperative indications to surgery and post-operative histopathological findings, was also performed.

RESULTS

Fifty-three patients were included in the TP-group and 73 in the CS-group. In 50 (39.7%) cases the frozen section changed the pre-operative surgical planning, with an extension of the pancreatic resection, in 43 (34.1%) cases up to a total pancreatectomy. Twenty-six patients (20.6%) with low-grade dysplasia at the frozen section underwent CS, while twenty (15.8%) underwent TP. Comparing these two sub-groups no differences were found in surgical IPMN recurrence, nor progression. The rate of overall postoperative complications was 56.6% in the TP-group and 57.5% in the CS-group (p = 0.940). Fifteen patients (20.5%) developed diabetes in the CS-group. None of the patients treated with CS developed a surgical IPMN recurrence or progression during the follow-up period. Comparing OS and DFS of the two groups, we did not find any statistically significant difference (p = 0.619 and 0.315).

CONCLUSION

A timely CS can be considered an appropriate and valid strategy in the surgical treatment of the majority of pancreatic IPMNs, as it can avoid the serious long-term metabolic consequences of TP in patients with a long-life expectancy. On the contrary, TP remains mandatory in case of PDAC or high-risk features involving the entire gland.

Predictive factors for long-term survival after surgery for pancreatic ductal adenocarcinoma: Making a case for standardized reporting of the resection margin using certified cancer center data

Factors for overall survival after pancreatic ductal adenocarcinoma (PDAC) seem to be nodal status, chemotherapy administration, UICC staging, and resection margin. However, there is no consensus on the definition for tumor free resection margin. Therefore, univariate OS as well as multivariate long-term survival using cancer center data was analyzed with regards to two different resection margin definitions. Ninety-five patients met inclusion criteria (pancreatic head PDAC, R0/R1, no 30 days mortality). OS was analyzed in univariate analysis with respect to R-status, CRM (circumferential resection margin; positive: ≤1mm; negative: >1mm), nodal status, and chemotherapy administration. Long-term survival >36 months was modelled using multivariate logistic regression instead of Cox regression because the distribution function of the dependent data violated the requirements for the application of this test. Significant differences in OS were found regarding the R status (Median OS and 95%CI for R0: 29.8 months, 22.3–37.4; R1: 15.9 months, 9.2–22.7; p = 0.005), nodal status (pN0 = 34.7, 10.4–59.0; pN1 = 17.1, 11.5–22.8; p = 0.003), and chemotherapy (with CTx: 26.7, 20.4–33.0; without CTx: 9.7, 5.2–14.1; p < .001). OS according to CRM status differed on a clinically relevant level by about 12 months (CRM positive: 17.2 months, 11.5–23.0; CRM negative: 29.8 months, 18.6–41.1; p = 0.126). A multivariate model containing chemotherapy, nodal status, and CRM explained long-term survival (p = 0.008; correct prediction >70%). Chemotherapy, nodal status and resection margin according to UICC R status are univariate factors for OS after PDAC. In contrast, long-term survival seems to depend on wider resection margins than those used in UICC R classification. Therefore, standardized histopathological reporting (including resection margin size) should be agreed upon.

In the Era of the Leeds Protocol: A Systematic Review and A Meta-Analysis on the Effect of Resection Margins on Survival Among Pancreatic Ductal Adenocarcinoma Patients

BACKGROUND AND AIMS

A positive resection margin is considered to be a factor associated with poor prognosis after pancreatic ductal adenocarcinoma resection. However, analysis of the resection margin is dependent on the pathological slicing technique. The aim of this systematic review and meta-analysis was to study the impact of resection margin on the survival of pancreatic ductal adenocarcinoma patients whose specimens were analyzed using the axial slicing technique.

MATERIAL AND METHODS

A systematic search in the PubMed, Cochrane, and Embase datasets covering the time period from November 2006 to January 2019 was performed. Only studies with axial slicing technique (Leeds Pathology Protocol or Royal College of Pathology Protocol) were included in the final database. Meta-analysis between the marginal distance and survival was performed with the Inverse Variance Method in RevMan.

RESULTS

The systematic search resulted in nine studies meeting the inclusion criteria. The median survival for a resection margin 0 mm ranged from 12.3 to 23.4 months, for resection margin <0.5 mm 16 months, for resection margin <1 mm ranged from 11 to 27.5 months, for resection margin <1.5 mm ranged from 16.9 to 21.2 months, and for resection margin >2 mm ranged from 53.9 to 63.1 months. Five studies were eligible for meta-analysis. The pooled multivariable hazard ratio favored resection margin ⩾1 mm (hazard ratio: 1.32 and 95% confidence interval: 1.03-1.68, p = 0.03).

CONCLUSION

Resection margins ⩾1 mm seem to lead to better survival in pancreatic ductal adenocarcinoma patients than resection margin <1 mm. However, there is not enough data to evaluate the effect of oncologic therapy or to analyze the impact of other resection margin distances on survival.

Surgical management and pathological assessment of pancreatoduodenectomy with venous resection: an international survey among surgeons and pathologists

BACKGROUND

The aim of this survey was to gain insights in the current surgical management and pathological assessment of pancreatoduodenectomy with portal-superior mesenteric vein resection (VR).

METHODS

A systematic literature search was performed to identify international expert surgeons (N = 150) and pathologists (N = 40) who published relevant studies between 2009 and 2019. These experts and Dutch surgeons (N = 17) and pathologists (N = 20) were approached to complete an online survey.

RESULTS

Overall, 76 (46%) surgeons and 37 (62%) pathologists completed the survey. Most surgeons (71%) estimated that preoperative imaging corresponded correctly with intraoperative findings of venous involvement in 50-75% of patients. An increased complication risk following VR was expected by 55% of surgeons, mainly after Type 4 (segmental resection-venous conduit anastomosis). Most surgeons (61%) preferred Type 3 (segmental resection-primary anastomosis). Most surgeons (75%) always perform the VR themselves. Standard postoperative imaging for patency control was performed by 54% of surgeons and 39% adjusted thromboprophylaxis following VR. Most pathologists (76%) always assessed tumor infiltration in the resected vein and only 54% of pathologists always assess the resection margins of the vein itself. Variation in assessment of tumor infiltration depth was observed.

CONCLUSION

This international survey showed variation in the surgical management and pathological assessment of pancreatoduodenectomy with venous involvement. This highlights the lack of evidence and emphasizes the need for research on imaging modalities to improve patient selection for VR, surgical techniques, postoperative management and standardization of the pathological assessment.

Essential updates 2018/2019: Current topics in the surgical treatment of pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is highly malignant. While cancers in other organs have shown clear improvements in 5-year survival, the 5-year survival rate of pancreatic cancer is approximately 10%. Early relapse and metastasis are not uncommon, making it difficult to achieve an acceptable prognosis even after complete surgical resection of the pancreas. Studies have been performed on various treatments to improve the prognosis of PDAC, and multidisciplinary approaches including non-surgical treatments have led to gradual improvement. In the present literature review, we have described the significance of anatomical and biological resectability criteria, the concept of R0 resection in surgical treatment, the feasibility of minimally invasive surgery, the remarkable development of perioperative chemotherapy, the effectiveness of conversion surgery for unresectable PDAC, and ongoing challenges in PDAC treatment. We also provide an essential update on these subjects by focusing on recent trends and topics.

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.

A Novel Nomogram to Predict Survival in Patients With Recurrence of Pancreatic Ductal Adenocarcinoma After Radical Resection

The post-progression survival (PPS) of patients with pancreatic ductal adenocarcinoma (PDAC) after radical resection is varied and influenced by the characteristics of tumor progression. We aimed to establish and validate a nomogram to predict PPS for PDAC patients after surgery. A total of 302 PDAC patients who had undergone curative resection from 2008 to 2018 were enrolled in this study and randomly divided into training and validation cohorts at a ratio of 3:1. The nomogram was established based on independent prognostic factors selected by LASSO and Cox regression and measured by the area under the receiver operating characteristic curve (AUC) and the concordance index (C-index). Significant prognostic factors included carbohydrate antigen 19-9 (CA19-9), lymph node (LN)9 metastasis, LN14 metastasis, LN16 metastasis, tumor differentiation, imaging-detected tumor size, local progression, liver-only metastasis, lung-only metastasis, and multiple metastases. The nomogram built on these factors showed powerful efficacy in PPS prediction, with C-index values of 0.751 (95% CI 0.692–0.0.810) and 0.710 (95% CI 0.645–0.755) for the training and validation cohorts, respectively. The AUC values for the 1-year and 2-year PSS rates were 0.745, 0.747, and 0.783, 0.748, respectively; these values were higher than those of the 8th tumor–node–metastasis (TNM) stage system. The exploration of risk factors and the establishment of a nomogram can provide new versions of personalized recurrence management for PDAC patients after surgery.

Survival benefit of adjuvant chemoradiotherapy for positive or close resection margin after curative resection of pancreatic adenocarcinoma

BACKGROUND

This study was conducted to identify patients who may benefit from adjuvant chemoradiotherapy (CRT) for positive or close resection margin (RM) after curative resection of pancreatic adenocarcinoma.

METHODS

From 2004 to 2015, total of 472 patients with pancreatic adenocarcinoma underwent curative resection. After excluding patients with RM > 2 mm or unknown, remaining 217 patients were retrospectively analyzed. Forty-six (21.2%) patients were treated with adjuvant chemotherapy alone (CTx; mainly gemcitabine-based), 142 (65.4%) with adjuvant CRT (mainly upfront), and 29 (13.4%) patients didn't receive any adjuvant therapy (noTx group).

RESULTS

Locoregional recurrence rate was significantly lower in the CRT group (43.7%) than in the CTx group (71.7%) or noTx group (65.5%) (p = 0.001). Significant survival benefits of CRT over CTx (HR 0.602, p = 0.020 for overall survival (OS); HR 0.599, p = 0.016 for time to any recurrence (TTR)) were demonstrated in multivariate analysis. CRT group had more 5-year survivors than other groups. In the subgroup analysis, such benefits of adjuvant CRT over CTx was observed only in patients with head tumor & vascular RM > 0.5 mm, but not in patients with body/tail tumor or vascular RM ≤ 0.5 mm. In the CRT group, radiation dose≥54 Gy was significantly associated with better TTR and OS.

CONCLUSIONS

Adjuvant CRT could improve TTR and OS compared to adjuvant CTx alone in patients with close RM under 2 mm. Radiation dose escalation may be beneficial when feasible. Modern CRT regimen-based randomized evidence is needed for these high-risk patients.

Clinical impacts of resection margin status and clinicopathologic parameters on pancreatic ductal adenocarcinoma

Background

The clinical relevance of pancreatic intraepithelial neoplasia (PanIN) at the resection margin of pancreatic ductal adenocarcinoma remains unknown. We aimed to investigate its clinical impact at the pancreatic transection margin (PTM) and, based on the result, determine the prognostic values of the resection margin status and other clinicopathologic parameters.

Patients and methods

We retrospectively analyzed 122 consecutive patients who underwent pancreatoduodenectomy or distal pancreatectomy between 2006 and 2018. Pathologic slides were reviewed and survival data were retrieved from institutional databases. Associations between two variables were investigated by Fisher’s exact test. Survival curves were generated by the Kaplan-Meier method. Prognostic factors were assessed using Cox regression analysis.

Results

Tumors were resected without leaving macroscopic remnants. The median follow-up period after surgery was 524.5 days. Cancer-related death (n = 72) was marginally and significantly associated with local recurrence (n = 22) and distant metastasis (n = 79), respectively. Local recurrence and distant metastasis occurred independently. After excluding cases with invasive cancer at any other margin, PanIN-2 or PanIN-3 (n = 21) at the PTM did not adversely affect prognoses compared with normal mucosa or PanIN-1 (n = 57) with statistical significance. R0 resection (n = 78), which is invasive cancer-free at all resection margins, showed somewhat better local recurrence-free and overall survivals as compared with R1 resection (n = 44), which involves invasive cancer at any resection margin, but the differences did not reach statistical significance. In contrast, differentiation grade and nodal metastasis were significant predictors of distant metastasis, and tumor location and differentiation grade were significant predictors of cancer-related death. Although there was no significant difference in differentiation grade between the head cancer and the body or tail cancer, nodal metastasis was significantly more frequent in the former than in the latter.

Conclusions

PanINs at the PTM did not adversely affect prognosis and R0 resection was not found to be a significant prognostic factor. Differentiation grade might be an indicator of occult metastasis and affect patients’ overall survival through distant metastasis. In addition to successful surgical procedures, tumor biology may be even more important as a predictor of postoperative prognosis.

Pancreatic resections in elderly patients with high American Society of Anesthesiologists' risk score: a view from a tertiary care center

BACKGROUND

More than 60% of patients affected by pancreatic cancer are ≥ 65 years of age. Surgery represents the only potentially curative treatment for malignant pancreatic neoplasia and a useful treatment for benign diseases.

AIM

To evaluate outcomes in elderly patients with ASA risk score 4 who underwent pancreatic resection compared to younger patients and elderly patients with lower anesthesiological risk.

METHODS

A consecutive series of 345 patients underwent pancreatic resection between 2010 and 2017 was reviewed. We compared three groups based on age at the time of surgery: < 65 years (group A), 65-74 years (group B), and ≥ 75 years (group C). Patients in group C were split into two subgroups, ASA 1-3 versus ASA 4, and compared.

RESULTS

Group A consisted of 117 (34%) patients, group B 128 (37%) patients, and group C 100 (29%) patients. Group C had a significantly higher incidence of comorbidity and ASA 4 status (p < 0.05), and of overall post-operative complications (p < 0.01), because of the higher incidence of post-operative medical complications. No differences in terms of overall surgical complications and post-operative mortality were reported. The mean overall survival was significantly lower for group C (p < 0.01), with no difference in mortality for cancer. Within group C, no differences were reported regarding surgical complications (p = 0.59), mortality (p = 0.34), and mean overall survival (p = 0.53) between ASA 1-3 and ASA 4 patients.

CONCLUSIONS

Advanced age should not preclude elderly patients with pancreatic diseases from being treated surgically, and ASA 4 in subjects aged ≥ 75 years should not be an absolute contraindication.

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.

Three-Dimensional Fixation: Pathological Protocol Following Pancreaticoduodenectomy with Portal Vein Resection for Pancreatic Cancer

BACKGROUND

Although existing histopathologic protocols for pancreatic cancer have been standardized, the relevance between prognosis and resection margin clearance is still controversial. Reconstruction of specimens as in situ to appropriately assess the margin is desirable in these protocols.

METHODS

The three-dimensional fixation protocol defined specimen handling of pancreaticoduodenectomy (PD) with portal vein (PV) resection. The superior mesenteric artery (SMA) margin of the specimen was tidily fixed around an artificial SMA as if in an in situ setting. In this prospective study, patients undergoing PD with PV resection for pancreatic cancer in 2016 were enrolled. To evaluate the feasibility of the three-dimensional fixation protocol, the SMA margin distance and PV involvement of tumor assessed by computed tomography (CT) were compared with those assessed by pathology.

RESULTS

Thirty-three patients with/without preoperative chemotherapy were enrolled. The entire cohort did not present with high-quality diagnostic assessment of the medial margins around SMA and PV (correct estimation, 58% and 73%, respectively). In contrast, in 16 patients undergoing upfront surgery, the concordance value of the SMA margin, which assesses the agreement between CT and pathology measures, was 0.48 (moderate agreement). The PV involvement examined by imaging was significantly associated with that by pathology (P = 0.013).

CONCLUSIONS

The three-dimensional fixation protocol was applicable to all cases undergoing PD with PV resection. Focusing on the patients with upfront surgery demonstrated the feasibility of accurate pathological assessment of medial margins. We propose this protocol as a promising standard for the assessment of true surgical margin status.

Positive Resection Margins Detected by Standardized Study of a Pancreaticoduodenectomy Sample: Is There Any Real Impact on Long-term Survival?

INTRODUCTION

The pathological evaluation of pancreaticoduodenectomy (PD) samples and the impact of R1 resections on survival has recently been questioned. This study evaluates the introduction of a standardized pathology study protocol (PSP) and the prognosis of R1 resections after long-term follow-up.

METHODS

We reviewed data from a prospectively maintained database regarding 109 periampullary tumors treated by PD from 2005 to 2013. The results of the introduction of a PSP were analysed, and the recurrence rate (RR), disease-free survival (DFS) and overall survival (OS) of the R1 resections were evaluated for each positive margin.

RESULTS

The PD specimens of periampullary tumors analyzed by PSP showed a higher rate of isolated lymph nodes (17 vs. 8; P=.003), N+ (60% vs. 31%; P<.001), microvascular invasion (67% vs. 34%; P=.001) and R1 resections (42% vs. 18%; P=.010). Pancreatic adenocarcinomas with R1 resection in the PSP group were compared with R0, presenting higher percentages of vascular resections (P=.033), N+ (P=.029), lymphatic and perineural invasion (P=.047; P=.029), higher RR (P=.026), lower DFS (P=.016) and lower OS (P=.025). Invasion of the medial margin correlated with a worse prognosis.

CONCLUSIONS

Our series shows an increase in R1 resection after the introduction of a PSP. Infiltration of the medial margin seems to be associated with a higher RR and a decrease in DFS and OS.

A Quantitative Clinicopathological Signature for Predicting Recurrence Risk of Pancreatic Ductal Adenocarcinoma After Radical Resection

Recurrence and distant metastases were main reasons of unfavorable outcomes for patients with pancreatic ductal adenocarcinoma (PDAC) after surgery. The aim of this study was to describe the patterns, timing, and predictors of recurrence or metastasis in PDAC patients after curative surgery. Patients with PDAC who underwent radical pancreatectomy were included. Associations between clinicopathological and radiological characteristics and specific pattern of progression were investigated. Least absolute shrinkage and selection operator (LASSO) and Cox regression were applied to assess the prognostic factors for overall survival (OS) and progression-free survival (PFS). A total of 302 patients were included into present study, and 173 patients were documented as recurrence after a median survival of 24.7 months. More than half of patients recurred after 12 months after surgery, and the liver was the most common metastatic site. Decreased time interval to progression, elevated carbohydrate antigen 19-9 (CA19-9) level, and lymph node (LN)16 metastasis were independent predictors for reduced OS. Independent prognostic factors for PFS included elevated carcinoembryonic antigen (CEA) level, local progression, liver or lung-only metastasis, local + distant progression, multiple metastases, LN16 metastasis, imaging tumor size, chemotherapy, and tumor–node–metastasis (TNM) stage. The predictive system showed valuable prediction performance with values of concordance indexes (C-indexes) and the area under the receiver operating characteristic curve (AUC) over 0.80. Different survival curves and predictive factors for specific patterns of disease progression suggested the biological heterogeneity, providing new versions into personal management of recurrence in PDAC patients after surgery.

Robotic-assisted versus laparoscopic left pancreatectomy at a high-volume, minimally invasive center

INTRODUCTION

While minimally invasive left pancreatectomy has become more widespread and generally accepted over the last decade, opinions on modality of minimally invasive approach (robotic or laparoscopic) remain mixed with few institutions performing a significant portion of both operative approaches simultaneously.

METHODS

247 minimally invasive left pancreatectomies were retrospectively identified in a prospectively maintained institutional REDCap™ database, 135 laparoscopic left pancreatectomy (LLP) and 108 robotic-assisted left pancreatectomy (RLP). Demographics, intraoperative variables, postoperative outcomes, and OR costs were compared between LLP and RLP with an additional subgroup analysis for procedures performed specifically for pancreatic adenocarcinoma (35 LLP and 23 RLP) focusing on pathologic outcomes and 2-year actuarial survival.

RESULTS

There were no significant differences in preoperative demographics or indications between LLP and RLP with 34% performed for chronic pancreatitis and 23% performed for pancreatic adenocarcinoma. While laparoscopic cases were faster (p < 0.001) robotic cases had a higher rate of splenic preservation (p < 0.001). Median length of stay was 5 days for RLP and LLP, and rate of clinically significant grade B/C pancreatic fistula was approximately 20% for both groups. Conversion rates to laparotomy were 4.3% and 1.8% for LLP and RLP approaches respectively. RLP had a higher rate of readmission (p = 0.035). Pathologic outcomes and 2-year actuarial survival were similar between LLP and RLP. LLP on average saved $206.67 in OR costs over RLP.

CONCLUSIONS

This study demonstrates that at a high-volume center with significant minimally invasive experience, both LLP and RLP can be equally effective when used at the discretion of the operating surgeon. We view the laparoscopic and robotic platforms as tools for the modern surgeon, and at our institution, given the technical success of both operative approaches, we will continue to encourage our surgeons to approach a difficult operation with their tool of choice.

R0 Versus R1 Resection Matters after Pancreaticoduodenectomy, and Less after Distal or Total Pancreatectomy for Pancreatic Cancer

OBJECTIVE

The aim of this study was to decipher the true importance of R0 versus R1 resection for survival in pancreatic ductal adenocarcinoma (PDAC).

SUMMARY OF BACKGROUND DATA

PDAC is characterized by poor survival, even after curative resection. In many studies, R0 versus R1 does not result in different prognosis and does not affect the postoperative management.

METHODS

Pubmed, Embase, and Cochrane databases were screened for prognostic studies on the association between resection status and survival. Hazard ratios (HRs) were pooled in a meta-analysis. Furthermore, our prospective database was retrospectively screened for curative PDAC resections according to inclusion criteria (n = 254 patients) between July 2007 and October 2014.

RESULTS

In the meta-analysis, R1 was associated with a decreased overall survival [HR 1.45 (95% confidence interval, 95% CI 1.37-1.52)] and disease-free survival [HR 1.44 (1.30-1.59)] in PDAC when compared with R0. Importantly, this effect held true only for pancreatic head resection both in the meta-analysis [R0 ≥0 mm: HR 1.21 (1.05-1.39) vs R0 ≥1 mm: HR 1.66 (1.46-1.89)] and in our cohort (R0 ≥0 mm: 31.8 vs 14.5 months, P < 0.001; R0 ≥1 mm, 41.2 vs 16.8 months; P < 0.001). Moreover, R1 resections were associated with advanced tumor disease, that is, larger tumor size, lymph node metastases, and extended resections. Multivariable Cox proportional hazard model suggested G3, pN1, tumor size, and R1 (0 mm/1 mm) as independent predictors of overall survival.

CONCLUSION

Resection margin is not a valid prognostic marker in publications before 2010 due to heterogeneity of cohorts and lack of standardized histopathological examination. Within standardized pathology protocols, R-status' prognostic validity may be primarily confined to pancreatic head cancers.

Pathology of pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive malignancy and estimated to become the second leading cause of cancer-related deaths by 2030. Although overall 5-year survival rates have constantly remained below 10% for the last decades, several key points important for accurate patient stratification have emerged during recent years. These key points include a highly standardized gross examination of PDAC resection specimens, using an axial slicing technique and inking of the circumferential resection margin (CRM), as well as a meticulous microscopic examination, taking into account the prognostic relevance of factors such as the exact resection status (R0 vs. R1 1-mm vs. R1 resection), histopathological tumor grading and the so-called lymph node ratio (LNR). With increasing use of neoadjuvant therapy in PDAC, tumor regression grading (TRG) for PDAC is currently rising in relevance in order to stratify and manage pre-operatively treated PDAC patients. As all current TRG systems for PDAC are unsatisfactory, new standardized international protocols are urgently needed. Several morphological subtypes of PDAC exist, some of which share the same molecular background with classical PDAC, while others are characterized by a distinct molecular pathogenesis. While some show a prognosis similar to classical PDAC, other subtypes stand out due to a better or even worse prognosis than classical PDAC. Prognostic relevant molecular subtypes of PDAC have been proposed as well, however, limitations of used cohorts and the lacking correlation of molecular subtypes with histomorphological subtypes limit the translation of these findings into valuable clinical applications. Lastly, several macroscopic and microscopic precursor lesions of PDAC have been described in genetically engineered mouse models (GEMM) and humans in recent times, providing further insight into PDAC carcinogenesis. In addition, improved diagnosis of PDAC precursors represents a chance to select patients for resection before invasive PDAC is present.

Comparison of Radical Antegrade Modular Pancreatosplenectomy with Standard Retrograde Pancreatosplenectomy for Left-Sided Pancreatic Cancer: A Meta-Analysis and Experience of a Single Center

BACKGROUND Radical antegrade modular pancreatosplenectomy (RAMPS) has been reported as a modified surgical technique used to achieve better margin resection and to retrieve more lymph nodes compared with standard retrograde pancreatosplenectomy (SRPS). MATERIAL AND METHODS A systematic literature review was performed to identify studies published in PubMed, EmBase, and Web of Science. Hazard ratio (HR), risk ratio (RR), weighted mean difference (WMD), and their 95% confidence intervals (95% CIs) were used as effect measures. In addition, the clinical data of 27 patients in our center were collected and retrospectively analyzed. RESULTS Seven studies containing 474 patients were finally enrolled in this meta-analysis. The pooled results showed that the RAMPS group had a better overall survival (OS) compared with the SRPS group (HR=0.65, 95% CI: 0.43-0.99, P=0.046; I²=41.8%, P=0.143). Significantly more lymph nodes were harvested in the RAMPS group compared with in the SRPS group (WMD=4.74, 95% CI: 0.36-9.12, P=0.034). Recurrence rate (RR=0.8, 95% CI: 0.66-0.98, P=0.028) and blood loss (WMD=-153.19 ml, 95% CI: -303.95 to -2.42, P=0.046) were both significantly reduced in the RAMPS group. Retrospective analysis results showed that only significantly more harvested lymph nodes were noted in the RAMPS group compared with the SRPS group (7.55±0.91 vs. 2.81±0.73, P=0.001). CONCLUSIONS Our study suggests that RAMPS has better prognosis and surgical outcomes than SRPS for left-sided pancreatic cancer. Nevertheless, more high-quality clinical trials are required to validate the result.

Validation of the American Joint Committee on Cancer 8th edition staging system for the pancreatic ductal adenocarcinoma

BACKGROUND & AIMS

The American Joint Commission on Cancer (AJCC) 8th edition staging system for pancreatic ductal adenocarcinoma (PDA) contains several significant changes. This study aimed to validate the AJCC 8th edition staging system of PDA.

METHODS

We analyzed patients with resected PDA between 2001 and 2017 using the Korean Pancreatic Cancer (K-PaC) registry. Overall survival (OS) was estimated using the Kaplan-Meier survival curves and compared via the log-rank test.

RESULTS

In total, 701 resected PDA patients were identified. During a median follow-up of 24.5 months, the median OS was 21.7 months. Meanwhile, the median OS of each stage according to the AJCC 8th edition was 73.5 months (stage IA), 41.9 months (stage IB), 24.2 months (stage IIA), 18.3 months (stage IIB), and 16.8 months (stage III). However, the new N-category (pN1 vs. pN2) did not subdivide prognosis, although the lymph node ratio (i.e., the ratio of the number of LN involved to the number of examined LN) did. Although pT3 and pN2 belong under stage III, pN2 has a significantly longer median OS than pT3 (16.9 months vs 11.2 months; p < 0.01).

CONCLUSION

The AJCC 8th edition staging system appropriately stratifies the prognosis of PDA patients. However, the cutoff of the N-category is not statistically valid, and the new stage III includes a heterogeneous category (pN2 and pT4). Therefore, we propose that stage III be divided into stage IIIA (Tany N2 M0) and stage IIIB (T4 Nany M0).

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.

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.

Clinical significance of revised microscopic positive resection margin status in ductal adenocarcinoma of pancreatic head

Purpose

Recent studies have suggested microscopic positive resection margin should be revised according to the presence of tumor cells within 1mm of the margin surface in resected specimens of pancreatic cancer. However, the clinical meaning of this revised margin status for R1 resection margin was not fully clarified.

Methods

From July 2012 to December 2014, the medical records of 194 consecutive patients who underwent pancreaticoduodenectomy for ductal adenocarcinoma of the pancreatic head were analyzed retrospectively. They were divided into 3 groups on margin status; revised microscopic negative margin (rR0) – tumor exists more than 1 mm from surgical margin, revised microscopic positive margin (rR1) – tumor present within less than 1 mm from surgical margin, classic microscopic positive margin (cR1) – tumor is exposed to surgical margin.

Results

There were 76 rR0 (39.2%), 100 rR1 (51.5%), and 18 cR1 (9.3%). There was significant difference in disease-free survival rates between cR1 vs. rR1 (8.4 months vs. 24.0 months, P = 0.013). Margin status correlated with local recurrence rate (17.1% in rR0, 26.0% in rR1, and 44.4% in cR1, P = 0.048). There is significant difference in recurrence at tumor bed (11.8% in rR0 vs. 23.0 in rR1, P = 0.050). Of rR1, adjuvant treatment was found to be an independent risk factor for local recurrence (hazard ratio, 0.297; 95% confidence interval, 0.127–0.693, P = 0.005).

Conclusion

Revised R1 resection margin (rR1) affects recurrence at the tumor bed. Adjuvant treatment significantly reduced local recurrence of rR1. Accordingly, adjuvant chemoradiation for rR1 group should be taken into account.

Pancreatoduodenectomy without Vascular Resection in Patients with Primary Resectable Adenocarcinoma and Unilateral Venous Contact: A Matched Case Study

PURPOSE

To investigate the oncological outcome and survival of patients following a conservative approach on the portal-mesenteric axis, in an intraoperative ultrasound-selected group of pancreatoduodenectomy (PD), performed on patients with primary resectable with vascular contact (prVC) pancreatic ductal adenocarcinoma (PDAC).

METHODS

A consecutive series of patients who underwent PD for PDAC at our tertiary care center, between 2008 and 2017, were reviewed. A total of 156 PDs and 88 total pancreatectomies were performed during the study period, including 35 vascular resections. We identified a group of 40 (25.6%) patients with prVC-PDAC in whom after checking the feasibility with intraoperative ultrasound, we were able to perform PD by separation of the tumor from the portomesenteric axis avoiding vascular resection, without residual macroscopic disease (no vascular resection, nvrPD), and compared this group, using case-matched methodology, with the standard PD (sPD) group of primary resectable without vascular contact- (prwVC-) PDAC.

RESULTS

The median follow-up was 28.5 ± 23.2 months in the sPD group and 23.8 ± 20.8 months in the nvrPD group (p = 0.35). Isolated local recurrence rate was 2/40 (5%) in both groups. Additionally, there were no statistical differences in the systemic progression of the disease (42.5% sPD vs. 45% nvrPD, p = 0.82) or local plus synchronous systemic disease rates (2.5% sPD vs. 7.5% nvrPD, p = 0.30). The median survival was 22 months for the sPD group and 23 months for the nvrPD group, p = 0.86. The overall survival was similar in the two groups (1 y: 76.3% sPD vs. 70.0% nvrPD; 3 y: 35.6% vs. 31.6%; and 5 y: 28.5% vs. 25.3%; p = 0.80). Conclusions. PD without vascular resection can be considered safe and oncologically acceptable in selected patients with preoperative diagnosis of prVC-PDAC. The poor prognosis of PDAC is related to the aggressive biology and systemic spread of the tumor, rather than the local control of the disease.

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.

Validation of at least 1 mm as cut-off for resection margins for pancreatic adenocarcinoma of the body and tail

BACKGROUND

The definition of resection margin (R) status in pancreatic cancer is under debate. Although a margin of at least 1 mm is an independent predictor of survival after resection for pancreatic head cancer, its relevance to pancreatic body and tail cancers remains unclear. This study aimed to validate R status based on a 1-mm tumour-free margin as a prognostic factor for resected adenocarcinoma involving the pancreatic body and tail.

METHODS

Patients who underwent distal or total pancreatectomy for adenocarcinomas of the pancreatic body and tail between January 2006 and December 2014 were identified from a prospective database. Resection margins were evaluated using a predefined cut-off of 1 mm. Rates of R0, R1 with invasion within 1 mm of the margin (R1 less than 1 mm), and R1 with direct invasion of the resection margin (R1 direct) were determined, and overall survival in each group assessed by Kaplan-Meier analysis. Univariable and multivariable Cox regression analyses were performed to identify predictors of survival.

RESULTS

R0 resection was achieved in 107 (23·5 per cent) and R1 in 348 (76·5 per cent) of 455 patients. Among R1 resections, invasion within 1 mm of the margin was found in 104 (22·9 per cent) and direct invasion in 244 (53·6 per cent). The R0 rate was 28·9 per cent after distal and 18·6 per cent after total pancreatectomy. In the total cohort, median survival times for patients with R0, R1 (less than 1 mm) and R1 (direct) status were 62·4, 24·6 and 17·2 months respectively, with 5-year survival rates of 52·6, 16·8 and 13·0 per cent (P < 0·001). In patients who received adjuvant chemotherapy, respective median survival times were 68·6, 32·8 and 21·4 months, with 5-year survival rates of 56, 22 and 16·0 per cent (P < 0·001). In multivariable analysis, R status was independently associated with survival.

CONCLUSION

A cut-off of at least 1 mm for evaluation of resection margins is an independent determinant of survival after resection of adenocarcinomas of the pancreatic body and tail.

Pathological Margin Clearance and Survival After Pancreaticoduodenectomy in a US and European Pancreatic Center

BACKGROUND

The optimal definition of a margin-negative resection and its exact prognostic significance on survival in resected pancreatic adenocarcinoma remains unknown. This study was designed to assess the relationship between pathological margin clearance, margin type, and survival.

METHODS

Patients who underwent pancreaticoduodenectomy with curative intent at two academic institutions, in Amsterdam, the Netherlands, and Boston, Massachusetts, between 2000 and 2014 were retrospectively evaluated. Overall survival, recurrence rates, and progression-free survival (PFS) were assessed by Kaplan-Meier estimates and multivariate Cox proportional hazards analysis, according to pathological margin clearance and type of margin involved.

RESULTS

Of 531 patients identified, the median PFS was 12.9, 15.4, and 24.1 months, and the median overall survival was 17.4, 22.9, and 27.7 months for margin clearances of 0, < 1, and ≥1 mm, respectively (all log-rank p < 0.001). On multivariate analysis, patients with a margin clearance of ≥1 mm demonstrated a survival advantage relative to those with 0 mm clearance [hazard ratio (HR) 0.71, p < 0.01], whereas survival was comparable for patients with a margin clearance of < 1 mm versus 0 mm (HR: 0.93, p = 0.60). Patients with involvement (0 or < 1 mm margin clearance) of the SMV/PV margin demonstrated prolonged median overall survival (25.7 months) relative to those with SMA involvement (17.5 months).

CONCLUSIONS

In patients undergoing pancreaticoduodenectomy for pancreatic adenocarcinoma, a margin clearance of ≥1 mm correlates with improved survival relative to < 1 mm clearance and may be a more accurate predictor of a complete margin-negative resection in pancreatic cancer. The type of margin involved also appears to impact survival.

Multicolour versus monocolour inking specimens after pancreaticoduodenectomy for periampullary cancer: A single centre prospective randomised clinical trial

BACKGROUND

R status represents an important prognostic factors in periampullary cancers. Thus, it is useful to verify if it can be influenced by different techniques of margination.

METHODS

Single-centre, randomised clinical trial of patients affected by periampullary cancer who underwent pancreaticoduodenectomies which included two different types of margination: arm A (multicolour inking) and arm B (monocolour inking). The primary endpoint was the overall R1 resection rate and its difference between the two arms. The secondary endpoints were the R1 resection rate in each margin and its difference between the two arms, and the impact of margin status on survival.

RESULTS

Fifty patients were randomised, 41 analysed: 22 in arm A, 19 arm B. The overall R1 status was 61%, without significant differences between the two arms. The margin most commonly involved was the superior mesenteric artery (SMA) (36.6%). A trend in favour of arm B was shown for the superior mesenteric artery margin (arm A = 22.7% versus arm B = 52.6%; P = 0.060). The anterior surface (P = 0.015), SMA (P = 0.047) and pancreatic remnant (P = 0.018) margins significantly influenced disease-free survival.

CONCLUSIONS

The R status was not influenced by different techniques of margination using a standardised pathological protocol. The SMA margin seemed to be the most important margin for evaluating both R status and disease-free survival.