Resectable adenocarcinomas in the pancreatic head: the retroperitoneal resection margin is an independent prognostic factor

Clinical outcomes in borderline and locally advanced pancreatic cancer with the addition of low-dose-rate brachytherapy to standard of care therapy

PURPOSE

Surgical resection remains the only curative therapy for pancreatic cancer. Unfortunately, many patients have borderline or unresectable disease at diagnosis due to proximity of major abdominal vessels. Neoadjuvant chemotherapy and radiation are used to down-stage, however, there is a risk that there will be a positive/close surgical margin. The CivaSheet is a low-dose-rate (LDR) brachytherapy device placed at the time of surgery to target the area of highest risk of margin positivity. The purpose of this study is to assess the clinical value of brachytherapy in addition to standard-of-care therapy in pancreatic therapy.

METHODS AND MATERIALS

Between 2017 and 2022 patients with borderline and locally advanced pancreatic cancer treated with neoadjuvant chemotherapy and radiation followed by surgical resection were included. There were 2 cohorts of patients: (1) Those who had the LDR brachytherapy device placed at the time of surgery and (2) those who did not. Sixteen of 19 (84%) patients who had brachytherapy were enrolled in a prospective clinical trial (NCT02843945). Patients were matched for comorbidities, cancer staging, and treatment details. The primary outcome was progression-free survival (PFS).

RESULTS

Thirty-five patients were included in this analysis, 19 in the LDR brachytherapy group and 16 in the comparison cohort. The 2-year PFS was 21% vs. 0% (p = 0.11), 2-year OS was 26% vs. 13% (p = 0.43), and the pancreatic cancer cause-specific survival was 84% vs. 56% (p = 0.13) in favor of the brachytherapy patients.

CONCLUSIONS

Use of LDR brachytherapy at the time of resection shows a trend towards improved progression free and overall survival for patients with borderline or locally advanced pancreatic cancer treated with neoadjuvant chemoradiation.

Anomalies of the right hepatic artery in periampullary cancer treatment: are pathological and clinical outcomes different? A single tertiary referral center retrospective analysis

PURPOSE

Anomalies of the right hepatic artery (RHA) may represent an additional challenge in pancreatoduodenectomy (PD). The aim of this study is to assess the potential impact of variations in hepatic arterial anatomy on perioperative outcomes.

METHODS

PDs performed for periampullary malignancies between 2017 and 2022 were retrospectively enrolled and subdivided in two groups: modal pattern of vascularization (MPV) and anomalous pattern of vascularization (APV). A propensity score matching (PSM) analysis was conducted to homogenize the two study populations. The two groups were then compared in terms of perioperative outcomes and pathological findings.

RESULTS

Thirty-eight patients (16.3%) out of 232 presented a vascular anomaly: an accessory RHA in 7 cases (3%), a replaced RHA in 26 cases (11.2%), and a replaced HA in 5 cases (2.1%). After PSM, 76 MPV patients were compared to the 38 APV patients. The incidence rate of postoperative complications was comparable between the two study populations (p=0.2). Similarly, no difference was detected in terms of histopathological data, including margin status. No difference was noted in terms of intraoperative hemorrhage and vascular resection.

CONCLUSION

When PDs are performed in high-volume centers, the presence of an APV of the RHA does not relate to a significant impact on perioperative complications. Moreover, no influence was noted on histopathological findings.

The Presence of an Aberrant Right Hepatic Artery Did Not Influence Surgical and Oncological Outcomes After Pancreaticoduodenectomy: A Comprehensive Systematic Review and Meta-Analysis

BACKGROUND

The presence of an aberrant right hepatic artery (a-RHA) could influence the oncological and postoperative results after pancreaticoduodenectomy (PD).

METHODS

A systematic review and metanalysis were conducted, including all comparative studies having patients who underwent PD without (na-RHA) or with a-RHA. The results were reported as risk ratios (RRs), mean differences (MDs), or hazard ratios (HRs) with 95% confidence intervals (95 CI). The random effects model was used to calculate the effect sizes. The endpoints were distinguished as critical and important. Critical endpoints were: R1 resection, overall survival (OS), morbidity, mortality, and biliary fistula (BL). Important endpoints were: postoperative pancreatic fistula (POPF), delayed gastric emptying (DGE), post pancreatectomy hemorrhage (PPH), length of stay (LOS), and operative time (OT).

RESULTS

Considering the R1 rate no significant differences were observed between the two groups (RR 1.06; 0.89 to 1.27). The two groups have a similar OS (HR 0.95; 0.85 to 1.06). Postoperative morbidity and mortality were similar between the two groups, with a RR of 0.97 (0.88 to 1.06) and 0.81 (0.54 to 1.20), respectively. The biliary fistula rate was similar between the two groups (RR of 1.09; 0.72 to 1.66). No differences were observed for non-critical endpoints.

CONCLUSION

The presence of a-RHA does not affect negatively the short-term and long-term clinical outcomes of PD.

Does minimally invasive surgery have a different impact on recurrence and overall survival in patients with pancreatic head versus body/tail cancer?

OBJECTIVE

This study sought to investigate the impact of minimally invasive surgery (MIS) on recurrence and overall survival between patients with pancreatic head versus body/tail cancers.

METHODS

The risk factors associated with recurrence and long-term outcomes were analyzed according to tumor location and operative modality.

RESULTS

A total of 288 and 87 patients underwent surgical resection for pancreatic head cancer and body/tail cancer, respectively. The perioperative outcomes and histopathologic results were comparable in open and MIS approach in both head and body/tail groups. There was no difference in local or systemic recurrence patterns and disease-free and overall survival rates according to primary tumor location and surgical modality. During subgroup analysis by stage; however, patients with stage III pancreatic head cancer in the MIS group had a decreased disease-free survival compared with those in the open surgery group (p = 0.020). On multivariate analysis, MIS was not a risk factor of total or local recurrences.

CONCLUSIONS

Recurrence patterns and overall survival rates of patients did not differ according to tumor location and surgical approach. However, patients with stage III pancreatic head cancer in the MIS group showed inferior disease-free survival relative to patients who underwent open surgery.

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).

Pancreatoduodenectomy En Bloc With Superior Mesenteric Artery Resection for Borderline Resectable Pancreatic Cancer - A Case Report and Literature Review

BACKGROUND/AIM

Pancreatic head adenocarcinoma represents the most aggressive digestive malignancy, which affects patients worldwide and is associated with poor outcomes especially due to the fact that most cases are diagnosed when local vascular invasion is already present.

CASE REPORT

This is a case report of a 44-year-old patient diagnosed with a borderline resectable pancreatic head adenocarcinoma invading the superior mesenteric artery. The patient was submitted to surgery, and intraoperatively the mesenteric artery invasion was found. A pancreatoduodenectomy en bloc with superior mesenteric artery resection was performed while the continuity of the arterial structure was re-established by placing a cadaveric graft.

CONCLUSION

In selected cases, extended arterial resections might be needed in order to achieve negative resection margins and therefore, to improve the chances of long-term survival.

Indocyanine green (ICG) fluorescence guide for the use and indications in general surgery: recommendations based on the descriptive review of the literature and the analysis of experience

Indocyanine Green is a fluorescent substance visible in near-infrared light. It is useful for the identification of anatomical structures (biliary tract, ureters, parathyroid, thoracic duct), the tissues vascularization (anastomosis in colorectal, esophageal, gastric, bariatric surgery, for plasties and flaps in abdominal wall surgery, liver resection, in strangulated hernias and in intestinal ischemia), for tumor identification (liver, pancreas, adrenal glands, implants of peritoneal carcinomatosis, retroperitoneal tumors and lymphomas) and sentinel node identification and lymphatic mapping in malignant tumors (stomach, breast, colon, rectum, esophagus and skin cancer). The evidence is very encouraging, although standardization of its use and randomized studies with higher number of patients are required to obtain definitive conclusions on its use in general surgery. The aim of this literature review is to provide a guide for the use of ICG fluorescence in general surgery procedures.

Can laboratory x-ray virtual histology provide intraoperative 3D tumor resection margin assessment?

Purpose: Surgery is an essential part of the curative plan for most patients affected with solid tumors. The outcome of such surgery, e.g., recurrence rates and ultimately patient survival, depends on several factors where the resection margin is of key importance. Presently, the resection margin is assessed by classical histology, which is time-consuming (several days), destructive, and basically only gives two-dimensional information. Clearly, it would be advantageous if immediate feedback on tumor extension in all three dimensions were available to the surgeon intraoperatively. Approach: We investigate a laboratory propagation-based phase-contrast x-ray computed tomography system that provides the resolution, the contrast, and, potentially, the speed for this purpose. The system relies on a liquid-metal jet microfocus source and a scintillator-coated CMOS detector. Our study is performed on paraffin-embedded non-stained samples of human pancreatic neuroendocrine tumors, liver intrahepatic cholangiocarcinoma, and pancreatic serous cystic neoplasm (benign). Results: We observe tumors with distinct and sharp edges having cellular resolution ( ∼ 10    μ m ) as well as many assisting histological landmarks, allowing for resection margin assessment. All x-ray data are compared with classical histology. The agreement is excellent. Conclusion: We conclude that the method has potential for intraoperative three-dimensional virtual histology.

Towards a More Standardized Approach to Pathologic Reporting of Pancreatoduodenectomy Specimens for Pancreatic Ductal Adenocarcinoma: Cross-continental and Cross-specialty Survey From the Pancreatobiliary Pathology Society Grossing Working Group

In recent literature and international meetings held, it has become clear that there are significant differences regarding the definition of what constitutes as margins and how best to document the pathologic findings in pancreatic ductal adenocarcinoma. To capture the current practice, Pancreatobiliary Pathology Society (PBPS) Grossing Working Group conducted an international multispecialty survey encompassing 25 statements, regarding pathologic examination and reporting of pancreatic ductal adenocarcinoma, particularly in pancreatoduodenectomy specimens. The survey results highlighted several discordances; however, consensus/high concordance was reached for the following: (1) the pancreatic neck margin should be entirely submitted en face, and if tumor on the slide, then it is considered equivalent to R1; (2) uncinate margin should be submitted entirely and perpendicularly sectioned, and tumor distance from the uncinate margin should be reported; (3) all other surfaces (including vascular groove, posterior surface, and anterior surface) should be examined and documented; (4) carcinoma involving separately submitted celiac axis specimen should be staged as pT4. Although no consensus was achieved regarding what constitutes R1 versus R0, most participants agreed that ink on tumor or at and within 1 mm to the tumor is equivalent to R1 only in areas designated as a margin, not surface. In conclusion, this survey raises the awareness of the discordances and serves as a starting point towards further standardization of the pancreatoduodenectomy grossing and reporting protocols.

Pancreatic malignancy in the backdrop of chronic pancreatitis: How much to push the boundaries to achieve R0 resection

Tumors of the body and tail of the pancreas are often more aggressive than tumors of the head and would have often undergone metastatic spread to other organs at the time of diagnosis. Most patients with carcinoma of the body and tail of the pancreas present at a late stage. Surgery is only indicated in those patients in whom there is no evidence of metastatic spread. Surgery is often not possible in cancers of the body and tail of the pancreas if the tumor invades celiac artery. Controversy exists regarding the margin status impact of microscopic resection margin involvement (R1) after pancreaticoduodenectomy (PD) for PDAC. There are reports indicating the rate of R1 resections increases significantly after PD if pathological examination is standardized. In this report, we present the case of a 56-year-old female who had undergone lateral pancreaticojejunostomy for chronic pancreatitis 8 years ago, but has now developed malignancy of the body and tail of the pancreas involving multiple organs. This patient underwent en bloc resection involving: 1. distal pancreatectomy with jejunal loop (lateral pancreaticojejunostomy) resection; 2. splenectomy; 3. left nephrectomy; 4. total gastrectomy; and 5. segmental colectomy with reconstruction by esophagojejunostomy, jejunojejunostomy, and colocolic anastomosis. The infrequent occurrence of tumor in the distal gland and advanced tumor stage at the time of diagnosis have both combined to produce therapeutic nihilism/dilemma in the minds of many surgeons. This report highlights the decision on how much to the push limits for multi-organ resection (en bloc resection with distal pancreatectomy, gastrectomy, splenectomy, colectomy, nephrectomy) with the intent of achieving R0 status in spite of the complexity of surgery in selected patients.

Exosomal microRNA in Pancreatic Cancer Diagnosis, Prognosis, and Treatment: From Bench to Bedside

Simple Summary

Pancreatic cancer is the fourth leading cause of cancer death in the United States and over 90% of the patients suffer from pancreatic ductal adenocarcinoma (PDAC). PDAC is the most lethal gastrointestinal malignancies and only 10% of the people survive more than 5 years, therefore, novel diagnostic, prognostic, and therapeutic strategies are an immediate necessity. Studies have demonstrated microRNAs in bodily fluids that are bound with membranes (exosomes) can act as stable biomarkers both for disease development and metastasis. The diagnostic, prognostic, as well as therapeutic roles of exosomal microRNAs in pancreatic cancer have been discussed in this review.

Abstract

Pancreatic cancer is the fourth leading cause of cancer death among men and women in the United States, and pancreatic ductal adenocarcinoma (PDAC) accounts for more than 90% of pancreatic cancer cases. PDAC is one of the most lethal gastrointestinal malignancies with an overall five-year survival rate of ~10%. Developing effective therapeutic strategies against pancreatic cancer is a great challenge. Novel diagnostic, prognostic, and therapeutic strategies are an immediate necessity to increase the survival of pancreatic cancer patients. So far, studies have demonstrated microRNAs (miRNAs) as sensitive biomarkers because of their significant correlation with disease development and metastasis. The miRNAs have been shown to be more stable inside membrane-bound vesicles in the extracellular environment called exosomes. Varieties of miRNAs are released into the body fluids via exosomes depending on the normal physiological or pathological conditions of the body. In this review, we discuss the recent findings on the diagnostic, prognostic, and therapeutic roles of exosomal miRNAs in pancreatic cancer.

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.

Impact of Margin Status on Survival in Patients with Pancreatic Ductal Adenocarcinoma Receiving Neoadjuvant Chemotherapy

BACKGROUND

Historically, a positive margin after pancreatectomy for pancreatic ductal adenocarcinoma (PDAC) was associated with decreased survival. In an era when neoadjuvant chemotherapy (NAC) is being used frequently, the prognostic significance of margin status is unclear.

STUDY DESIGN

Patients with localized PDAC who received NAC and underwent pancreatectomy from 2011 to 2018 were identified from a single-institution database. Patients with fewer than 2 months of NAC, R2 resection, or fewer than 90 days of follow-up were excluded. A positive margin included tumors within 1 mm of the surgical margin.

RESULTS

Four hundred and sixty-eight patients met inclusion criteria. Median age was 65 years and 53% were female. Preoperative clinical staging demonstrated that most had locally advanced (n = 222 [47%]) or borderline resectable (n = 172 [37%]) disease. Median follow-up was 18.5 months (interquartile range 10.6 to 30.0 months). Median duration of NAC was 119 days (interquartile range 87 to 168 days). FOLFIRINOX was first-line therapy for 67%, and 73% received neoadjuvant radiotherapy. Most underwent pancreaticoduodenectomy (69%). Forty percent were node-positive and 80% had an R0 resection. Fifty-six percent received at least 1 cycle of adjuvant therapy. Median overall survival and recurrence-free survival were 22.0 months (95% CI, 19.4 to 25.1 months) and 11.0 months (95% CI, 10.0 to 12.1 months). On multivariate analysis, margin status was not a significant predictor of overall survival or recurrence-free survival. Factors associated with overall survival included clinical stage, duration of NAC, nodal status, histopathologic treatment response score, and receipt of adjuvant chemotherapy.

CONCLUSIONS

Microscopic margin positivity is not associated with recurrence and survival in localized PDAC patients resected after treatment with NAC. Aggressive surgical extirpation in high-volume centers should be considered in selected patients after extensive NAC.

En bloc proximal peri-mesenteric clearance for pancreatic head cancer surgery

The superior mesenteric artery (SMA) first approach and meso-pancreas excision (MPE) during pancreatoduodenectomy (PD) for pancreatic head cancer have been suggested for complete local tumor control, less operative blood loss, and early determination of resectability. However, SMA-first approach is merely a mode of approach and the concept of MPE has been challenged due to its anatomical obscurity. Dissection around proximal mesenteric vessels, superior mesenteric vein and SMA, is a critical procedure point for local tumor control as tumor infiltration is frequently observed both at the time of initial diagnosis and recurrence. The meso-pancreas, which encompasses the soft tissue between the uncinated process and SMA, does not include all the aforementioned points of proximal mesenteric areas. Therefore, the authors propose a new terminology named, “en bloc proximal peri-mesenteric clearance (PPMC)”, to describe the removal of all the lymph nodes including soft tissue around proximal mesenteric vessels, especially the SMA, to ensure complete local tumor control of pancreatic head cancer. The SMA-first approach applied either by the mesenteric approach or supra-colic approach can make this procedure more feasible. The extent of the circumferential dissection of the peri-SMA nerve plexus can be adjusted according to the primary disease. PPMC including the removal of all lymph nodes around the proximal SMA may be considered as a standard extent of PD for pancreatic head cancer.

Is Laparoscopic Pancreaticoduodenectomy Feasible for Pancreatic Ductal Adenocarcinoma?

Simple Summary

Pancreatic cancer is known to be one of the most lethal malignant diseases in gastrointestinal tract. Margin-negative pancreatectomy followed by postoperative adjuvant chemotherapy is essential treatment for long-term survival. Due to anatomical complexity and technical difficulty, laparoscopic pancreaticoduodenectomy is still controversial. However, with the advance of laparoscopic surgery, laparoscopic pancreatic resection of pancreatic head cancer has been carefully applied in well selected patients. The accumulating data are suggesting its technical feasibility, safety, and potential equivalent long-term oncologic outcome. In this review, the current status of laparoscopic pancreaticoduodenectomy for pancreatic head cancer is summarized. In addition, potential surgical indications and future perspectives of laparoscopic pancreaticoduodenectomy for pancreatic cancer are discussed for safe implementation in our clinical practice.

Abstract

Margin-negative radical pancreatectomy is the essential condition to obtain long-term survival of patients with pancreatic cancer. With the investigation for early diagnosis, introduction of potent chemotherapeutic agents, application of neoadjuvnat chemotherapy, advancement of open and laparoscopic surgical techniques, mature perioperative management, and patients’ improved general conditions, survival of the resected pancreatic cancer is expected to be further improved. According to the literatures, laparoscopic pancreaticoduodenectomy (LPD) is also thought to be good alternative strategy in managing well-selected resectable pancreatic cancer. LPD with combined vascular resection is also feasible, but only expert surgeons should handle these challenging cases. LPD for pancreatic cancer should be determined based on surgeons’ proficiency to fulfil the goals of the patient’s safety and oncologic principles.

Novel morphological classification of the normal pancreatic uncinate process based on computed tomography

Objectives

This study aimed to assess computed tomographic (CT) features of the normal pancreatic uncinate process (UP) and to classify UP types on the basis of morphological characteristics.

Methods

From November 2017 to December 2018, consecutive Han Chinese adults were enrolled in this retrospective study. Morphometric evaluation of the UP was performed using CT imaging, including assessment of the maximal transverse diameter of the UP (MTDUP) and pancreas head, and assessment of the relationship between the UP and superior mesenteric vessels.

Results

A total of 318 participants were studied. The mean MTDUP and maximal transverse diameter of the pancreas head were 15.89 ± 4.82 mm and 46.47 ± 7.18 mm, respectively. The mean MTDUP was 10.83 ± 2.59 mm for type I UP (21.70% of participants), 13.87 ± 2.35 mm for type II (13.21%), 17.08 ± 3.43 mm for type III (56.29%), and 23.74 ± 5.02 mm for type IV (8.81%). There was a significant difference among the UP types.

Conclusions

Four types of normal UP can be defined on the basis of morphological CT features. The length of the UP significantly increases from types I to IV, and type III accounts for > 50%.

First report on the feasibility of a permanently implantable uni-directional planar low dose rate brachytherapy sheet for patients with resectable or borderline resectable pancreatic cancer

BACKGROUND

Margin negative resection in pancreatic cancer remains the only curative option but is challenging, especially with the retroperitoneal margin. Intraoperative radiation therapy (IORT) can improve rates of local control but requires specially designed facilities and equipment. This retrospective review describes initial results of a novel implantable mesh of uni-directional low dose rate (LDR) Pd-103 sources (sheet) used to deliver a focal margin-directed high-dose boost in patients with concern for close or positive margins.

METHODS

Eleven consecutive patients from a single institution with resectable or borderline resectable pancreatic cancer with concern for positive margins were selected for sheet placement and retrospectively reviewed. Procedural outcomes, including the time to implant the device and complications, and clinical outcomes, including survival and patterns of failure, are reported. A dosimetric comparison of the LDR sheet with hypothetical stereotactic body radiotherapy (SBRT) boost is reported.

RESULTS

One patient had a resectable disease, and 10 patients had a borderline resectable disease and underwent neoadjuvant treatment. Sheet placement added 15 min to procedural time with no procedural or sheet-related complications. At a median follow up of 13 months, 64% (n = 7) of patients are alive and 55% (n = 6) are disease-free. Compared to a hypothetical SBRT boost, the LDR sheet delivered a negligible dose to kidneys, liver, and spinal cord with a 50% reduction in max dose to the small bowel.

CONCLUSION

This is the first report of the use of an implantable uni-directional LDR brachytherapy sheet in patients with resected pancreatic cancer with concern for margin clearance, with no associated toxicity and favorable clinical outcomes.

Comparing Pathology Report Quality Indicators in 2 Distinct Whipple Resection Specimen Protocols

OBJECTIVES

Pancreaticoduodenectomy specimens are complex, with varying gross examination techniques. In 2012, our institution began using axial sectioning. We sought to determine if this resulted in more complete pathology reporting.

METHODS

Quality indicators were analyzed for pathology reports from 2 cohorts: 2001 to 2009 grossed traditionally and 2012 to 2017 using an axial technique (n = 81 and 51). Continuous and categorical data were compared using 2-tailed t test and Fisher exact test, respectively.

RESULTS

The later cohort exhibited increased reporting of stage, lymphovascular invasion, margins/surfaces, mean number of lymph nodes, and mean number of slides (P < 0.01). No differences were seen in reporting of size, grade, or perineural invasion. In the later cohort, superior mesenteric vein/portal vein surface was positive in 17 cases (33%), showing strong correlation with superior mesenteric artery/uncinate margin involvement (13/17 cases; P = 0.0001). There was a higher rate of lymph node positivity (86% vs 65%, P < 0.01) in the later cohort.

CONCLUSIONS

There is a trend toward higher-quality pathology reports in 2012 to 2017. A possible drawback of the axial approach is increased histopathology slides. Potential additional contributors include College of American Pathologists protocols, increasing subspecialty practice, and updates to the American Joint Committee on Cancer staging criteria.

Towards an Optical Biopsy during Visceral Surgical Interventions

Background

Cancer will replace cardiovascular diseases as the most frequent cause of death. Therefore, the goals of cancer treatment are prevention strategies and early detection by cancer screening and ideal stage therapy. From an oncological point of view, complete tumor resection is a significant prognostic factor. Optical coherence tomography (OCT) and confocal laser microscopy (CLM) are two techniques that have the potential to complement intraoperative frozen section analysis as in vivo and real-time optical biopsies.

Summary

In this review we present both procedures and review the progress of evaluation for intraoperative application in visceral surgery. For visceral surgery, there are promising studies evaluating OCT and CLM; however, application during routine visceral surgical interventions is still lacking.

Key Message

OCT and CLM are not competing but complementary approaches of tissue analysis to intraoperative frozen section analysis. Although intraoperative application of OCT and CLM is at an early stage, they are two promising techniques of intraoperative in vivo and real-time tissue examination. Additionally, deep learning strategies provide a significant supplement for automated tissue detection.

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.

Pancreatic cancer surgical management

Pancreatic ductal adenocarcinoma (PDAC) remains a dismal prognosis and surgery is the only chance for cure. However, only few of the patients have localized tumor eligible for curative complete resection. Preoperative management and well-staging of the disease are the cornerstone for appropriate surgery and major issues to define the best therapeutic strategy. This review focuses on the surgical and optimal perioperative management of PDAC and summarizes updates data on the subject.

Clinical relevance of pancreatobiliary and intestinal subtypes of ampullary and duodenal adenocarcinoma: Pattern of recurrence, chemotherapy, and survival after pancreatoduodenectomy

BACKGROUND

The clinical relevance of the classification of ampullary adenocarcinoma (AC) into pancreatobiliary (PB) or intestinal (Int) subtypes has not been resolved.

METHODS

Clinicopathological factors, survival, and localization and treatment of recurrence were investigated for patients with AC and duodenal adenocarcinoma (DC) treated by pancreatoduodenectomy from 2000 to 2015.

RESULTS

A total of 109 AC (45 PB, 64 Int) and 71 DC (all Int) were identified. Median overall survival (OS) for ACPB vs DC vs ACInt was 43.6 vs 51 vs 75 months, respectively. ACPB had significantly shorter OS than ACInt (p = 0.036). However, for AC stage (HR = 2.39; 95 %CI 1.23-4.64, p = 0.010) was the only factor associated with mortality risk in multivariate analysis. Localization of recurrence (n = 88) was predominantly distant (ACPB 81.5%; ACInt 92%; DC 91.7%, p = 0.371). Post-recurrence survival (PRS) for ACPB, ACInt and DC did not differ (6.9 vs 9.2 vs 7.5 months, p = 0.755). Best supportive care or palliative chemotherapy were offered for recurrent disease to 44.5%/48.1% for ACPB, 40%/56% for ACInt, and 41.7%/52.8% for DC (p = 0.947). The choice of chemotherapy regimen varied considerably. Five patients underwent surgical resection or ablation with curative intent. All deaths among ACPB were caused by recurrent disease, whereas 29.4% of ACInt and 23.1% of DC deaths was non-cancer related or caused by other specific cancer.

CONCLUSION

ACPB, ACInt and DC have similar recurrence patterns and PRS. The difference in survival between ACPB and ACInt was not statistically significant when stratified by stage. The optimal chemotherapy in patients with recurrent AC remains undefined.

Prediction of Recurrence With KRAS Mutational Burden Using Ultrasensitive Digital Polymerase Chain Reaction of Radial Resection Margin of Resected Pancreatic Ductal Adenocarcinoma

OBJECTIVE

Although complete surgical resection is the only curative method for pancreatic cancer, the radial resection margins of pylorus-preserving pancreaticoduodenectomy specimens might be underevaluated.

METHODS

KRAS mutation was assessed with droplet digital polymerase chain reaction on cells collected from the radial resection margins of 81 patients, and the results were compared with those of conventional pathologic resection margin (pRM) evaluation.

RESULTS

KRAS mutation was detected in 76 patients (94%), and molecular resection margin (mRM) positivity defined by a KRAS mutation rate of 4.19% or greater was observed in 18 patients (22%). Patients with mRM-positive had significantly worse recurrence-free survival (RFS) than those with mRM-negative in entire groups (P = 0.008) and in subgroups without chemotherapy or radiation therapy (all, P < 0.001). When combined pRMs-mRMs were evaluated, patients with combined pRM-mRM-positive (either pRM- or mRM-positive) had significantly worse RFS than those with combined resection margin-negative (both pRM and mRM negative) by univariate (P = 0.002) and multivariate (P = 0.03) analyses.

CONCLUSIONS

KRAS mutational analysis with ultrasensitive droplet digital polymerase chain reaction of the radial resection margin in pancreatic cancer patients who underwent pylorus-preserving pancreaticoduodenectomy can provide more accurate information on RFS by using alone or in combination with conventional pRM evaluation, especially in patients without chemotherapy or radiation therapy.

Ampullary Cancer

Compared with other periampullary tumors, cancers of the ampulla of Vater are rare. These tumors tend to present earlier than their pancreatic and distal bile duct brethren. In addition to the hypothesis that they are also less biologically aggressive, ampullary cancers tend to have better survival than other types of periampullary cancers. The mortality from this disease remains high, and much can still be learned about ampullary cancers.

Correlation between appearance of the retroportal fat plane at preoperative CT and pathology findings in resected adenocarcinoma of the pancreatic head

AIM

To correlate the appearance of the retroportal fat plane at preoperative computed tomography (CT) and the pathology findings in resected adenocarcinoma of the pancreatic head (PDAC).

MATERIAL AND METHODS

Forty-eight patients with resected PDAC of the pancreatic head were included (24 men, 24 women, mean age 63 years, median BMI 24.1). All patients underwent CT <30 days before surgery. The state of the retroperitoneal resection margin and the presence of lymphatic or perineural invasion were obtained from pathology reports. CT images were reviewed independently by two radiologists for assessment of the retroportal fat plane and graded in two categories (clear/effaced). Inter-reader discrepancies were solved in consensus. Interobserver agreement was calculated and Fisher's test was used to assess the correlation between CT and pathology findings. Visceral fat areas were measured and correlated with CT findings.

RESULTS

A clear retroportal fat plane was significantly associated with a negative retroperitoneal margin at pathology with 100% specificity and PPV (p=0.0001). No association was observed between the appearance of the fat plane at CT and the presence of lymphatic or perineural invasion (p=ns). Interobserver agreement for retroportal fat plane evaluation was good (0.741). False-positive cases had a significantly lower visceral fat area than the correctly classified patients (p=0.0480).

CONCLUSIONS

A clear retroportal fat plane is significantly associated with negative retroperitoneal resection margins at pathology. The lack of visceral adipose tissue can lead to overestimation of retroportal fat plane involvement at preoperative CT.

Surgical Margin Status of Patients with Pancreatic Ductal Adenocarcinoma Undergoing Surgery with Radical Intent: Risk Factors for the Survival Impact of Positive Margins

BACKGROUND

For pancreatic ductal adenocarcinoma (PDAC), surgical margin status is an important pathological factor for evaluating surgical adequacy. In this study, we attempted to investigate predictive factors for the survival impact of positive surgical margins.

MATERIALS AND METHODS

From February 2004 to December 2013, 204 patients were diagnosed with PDAC and underwent surgery with radical intent; 189 patients fulfilled our selection criteria and were enrolled for analysis.

RESULTS

For the 189 enrolled patients with PDAC, we found male predominance (112/189, 59%) and a median age of 64 years; most patients were diagnosed with stage IIB disease (n=115, 61%). The positive surgical margin rate was 21% (n=40). Carbohydrate antigen 19-9 (CA19-9) level higher than 246 U/ml (odds ratio (OR)=2.318; 95% confidence interval (CI)=1.037-5.181 p=0.040) and lesion location in the uncinate process (OR=2.996; 95% CI=1.232-7.284 p=0.015) were the only two independent risk factors for positive surgical margins. Positive retroperitoneal soft-tissue margins were the most frequently observed (24/40, 60%). Overall, positive surgical margins had no survival impact in the 189 patients with PDAC who underwent surgery; however, positive surgical margins had an unfavorable survival impact on patients with stage IIA PDAC who underwent surgery.

CONCLUSION

Retroperitoneal soft-tissue was the most common site for positive surgical margins. Additionally, surgical margin positivity was more likely for tumors located in the uncinate process than for other tumors. Positive surgical margins had an unfavorable survival impact on patients with stage IIA PDAC who underwent surgery.

Indocyanine Green Perfusion Imaging-Guided Laparoscopic Pancreaticoduodenectomy: Potential Application in Retroperitoneal Margin Dissection

BACKGROUND

During laparoscopic pancreaticoduodenectomy (LPD), dissecting uncinate process from the superior mesenteric artery (SMA) will determine one of the important surgical margins (retroperitoneal margin) for predicting oncological outcomes and the quality of LPD. However, clear identification of the division line for retroperitoneal margin is not easy as the uncinate process of the pancreas is anatomically very close to SMA and intermingled with the nerve plexus and soft tissues around SMA. In this study, we present data regarding the potential usefulness of indocyanine green (ICG)-enhanced approach in obtaining retroperitoneal margin during LPD.

METHODS

From January to September 2017, medical records of patients who underwent LPD for periampullary pathological conditions were retrospectively reviewed. ICG (5 mg/2 cm³) was prepared and intravenously injected when dissecting uncinate process of the pancreas. Perioperative outcomes, including gender, age, diagnosis, body mass index, operation time, estimated blood loss, transfusion, presence of postoperative pancreatic fistulas (POPFs), and length of hospital stay, were evaluated.

RESULTS

During the study period, a total of 37 patients underwent LPD for periampullary pathological lesions. Among them, ICG-enhanced dissection of uncinate process of the pancreas was applied in 10 patients (27%). All patients were able to obtain margin-negative resection. There were no significant differences between the perioperative outcomes of patients who did and did not undergo ICG-enhanced approach.

DISCUSSION

ICG perfusion-based laparoscopic dissection of retroperitoneal margin is feasible and safe in LPD. This intraoperative visual difference can provide the surgeon with very helpful real-time visual information. Further study is mandatory.

Dilemmas for the pathologist in the oncologic assessment of pancreatoduodenectomy specimens : An overview of different grossing approaches and the relevance of the histopathological characteristics in the oncologic assessment of pancreatoduodenectomy specimens

A pancreatoduodenectomy specimen is complex, and there is much debate on how it is best approached by the pathologist. In this review, we provide an overview of topics relevant for current clinical practice in terms of gross dissection, and macro- and microscopic assessment of the pancreatoduodenectomy specimen with a suspicion of suspected pancreatic cancer. Tumor origin, tumor size, degree of differentiation, lymph node status, and resection margin status are universally accepted as prognostic for survival. However, different guidelines diverge on important issues, such as the diagnostic criteria for evaluating the completeness of resection. The macroscopic assessment of the site of origin in periampullary tumors and cystic lesions is influenced by the grossing method. Bi-sectioning of the head of the pancreas may offer an advantage in this respect, as this method allows for optimal visualization of the periampullary area. However, a head-to-head comparison of the assessment of clinically relevant parameters, using axial slicing versus bi-sectioning, is not available yet and the gold standard to compare both techniques prospectively might be subject of debate. Further studies are required to validate the various dissection protocols used for pancreatoduodenectomy specimens and their specific value in the assessment of pathological parameters relevant for prognosis.

Value of surgical resection and timing of therapy in patients with pancreatic cancer at high risk for positive margins

Background

Surgical resection remains the best chance at long-term survival in pancreatic cancer, though margin-positive resections are associated with diminished survival. We examined the effect of margin-positive resection on survival, as well as the role and timing of additional therapies through the National Cancer Database (NCDB).

Patients and methods

Patients with stage IIA–III pancreatic adenocarcinoma diagnosed from 2004 to 2013 were identified in NCDB. Survival was compared using univariate and multivariate Cox proportional hazards modelling for patients who underwent surgery with negative (R0), microscopically positive (R1) and macroscopically positive (R2) margins or non-surgical treatment. We further analysed patients by margin status, timing of additional therapy (neoadjuvant therapy (NAT) vs adjuvant therapy (AT) vs none) and clinical stage.

Results

We analysed 44 852 patients. Median survival (MS) for patients who did not undergo surgery was 10.3 months, compared with 19.7 months for R0 (P<0.001), 14.3 months for R1 (P<0.001) and 9.8 months (P=0.07) for R2 resections. NAT (MS 23.2 months) was associated with improved survival compared with AT (MS 21.5 months) in negative-margin patients and equivalent (MS 17.6 months) to AT (MS 16.8 months) in positive-margin patients. Survival for stage III NAT positive-margin patients (MS 19.8 months) was equivalent to AT after negative margins (MS 18.4 months, P=1.00). Improved R0 rates were seen with NAT (88% vs 81%, P<0.001), especially in stage III patients (85% vs 59%, P<0.001).

Conclusion

R1 resections portend poorer survival than R0 but do not negate the benefit of surgery when additional therapy is given. NAT was associated with improved R0 rates and improved survival for stage III positive-margin patients.

Identifying the neck margin status of ductal adenocarcinoma in the pancreatic head by multiphoton microscopy

Complete surgical resection is the only option for improving the survival of patients with ductal adenocarcinoma in the pancreatic head. After resection, determining the status of resection margins (RMs) is crucial for deciding on the nature of the follow-up treatment. The purpose of this study was to evaluate whether multiphoton microscopy (MPM) could be considered a reliable tool for determining the status of pancreatic neck margins by identifying tumour cells of ductal adenocarcinoma in these margins in the pancreatic head, and our results were affirmative. In particular, MPM could identify tumour cells in the nerves. It was also found that the quantification of the difference between normal duct cells and tumour cells was possible. In addition, the content of collagen could be quantified and used as a marker for differentiating ductal adenocarcinoma in the pancreatic head from normal pancreatic tissues, eventually leading to the identification of R0 and R1 resections of the pancreatic neck margin. With the development of the clinical applications of the multiphoton endoscope, MPM has the potential to provide in vivo real-time identification of RM status during surgery.

Updated therapeutic outcome for patients with periampullary and pancreatic cancer related to recent translational research

Chemotherapy with improved effect in patients with metastatic pancreatic cancer has recently been established, launching a new era for patients with this very aggressive disease. FOLFIRINOX and gemcitabine plus nab-paclitaxel are different regimens, both capable of stabilizing the disease, thus increasing the number of patients who can reach second line and even third line of treatment. Concurrently, new windows of opportunity open for nutritional support and other therapeutic interventions, improving quality of life. Also pancreatic surgery has changed significantly during the latest years. Extended operations, including vascular/multivisceral resections are frequently performed in specialized centers, pushing borders of resectability. Potentially curative treatment including neoadjuvant and adjuvant chemotherapy is offered new patient groups. Translational research is the basis for the essential understanding of the ongoing development. Even thou biomarkers for clinical management of patients with periampullary tumors have almost been lacking, biomarker driven trials are now in progress. New insight is constantly made available for clinicians; one recent example is selection of patients for gemcitabine treatment based on the expression level of the human equilibrium nucleoside transporter 1. An example of new diagnostic tools is identification of early pancreatic cancer patients by a three-biomarker panel in urine: The proteins lymphatic vessel endothelial hyaluronan receptor 1, regenerating gene 1 alpha and translation elongation factor 1 alpha. Requirement of treatment guideline revisions is intensifying, as combined chemotherapy regimens result in unexpected advantages. The European Study Group for Pancreatic Cancer 4 trial outcome is an illustration: Addition of capecitabine in the adjuvant setting improved overall survival more than expected from the effect in advanced disease. Rapid implementation of new treatment options is mandatory when progress finally extends to patients with this serious disease.

The impact of margin status determined by the one-millimeter rule on tumor recurrence and survival following pancreaticoduodenectomy for pancreatic ductal adenocarcinoma

PURPOSE

The tumor-node-metastasis (TNM) classification defines R1 as the presence of tumor cells at the resection margin, while the current Royal College of Pathologists guidelines for pancreaticoduodenectomy specimens regard the presence of tumor cells within 1 mm from the resection margin as R1 (the "1-mm rule"). The aims of this study were to investigate the resection margin status of pancreatic head cancer retrospectively according to both the TNM and 1-mm rule classifications, and to evaluate the postoperative survival and tumor recurrence patterns.

METHODS

A total of 117 patients with pancreatic head cancer were the subjects of this study.

RESULTS

R1^{1-mm rule} resection was associated with a significantly worse disease-free survival (DFS) than R0^{1-mm rule} resection (p = 0.0259), while R1^TNM had no impact on DFS. R1^{1-mm rule} resection margin status correlated with the incidence of tumor recurrence in the liver (p = 0.0483). In a multivariate analysis, R1^{1-mm rule} resection was the independent variable for predicting poor DFS (hazard ratio 1.71; p = 0.0289).

CONCLUSIONS

R1 resection margin status determined by the 1-mm rule may be an independent indicator for predicting disease recurrence, especially liver metastasis. These results may be useful for selecting the appropriate adjuvant therapy protocol and conducting strict surveillance in PDAC patients.

Impact of Resection Margin Distance on Survival of Pancreatic Cancer: A Systematic Review and Meta-Analysis

Purpose

While curative resection is the only chance of cure in pancreatic cancer, controversies exist about the impact of surgical margin status on survival. Non-standardized pathologic report and different criteria on the R1 status made it difficult to implicate adjuvant therapy after resection based on the margin status. We evaluated the influence of resection margins on survival by meta-analysis.

Materials and Methods

We thoroughly searched electronic databases of PubMed, EMBASE, and Cochrane Library. We included studies reporting survival outcomes with different margin status: involved margin (R0 mm), margin clearance with ≤ 1 mm (R0-1 mm), and margin with > 1 mm (R>1 mm). Hazard ratio (HR) for overall survival was extracted, and a random-effects model was used for pooled analysis.

Results

A total of eight retrospective studies involving 1,932 patients were included. Pooled HR for overall survival showed that patients with R>1 mm had reduced risk of death than those with R0-1 mm (HR, 0.74; 95% confidence interval [CI], 0.61 to 0.88; p=0.001). In addition, patients with R0-1 mm had reduced risk of death than those with R0 mm (HR, 0.81; 95% CI, 0.72 to 0.91; p < 0.001). There was no heterogeneity between the included studies (I² index, 42% and 0%; p=0.10 and p=0.82, respectively).

Conclusion

Our results suggest that stratification of the patients based on margin status is warranted in the clinical trials assessing the role of adjuvant treatment for pancreatic cancer.

Redefining the R1 resection in patients with pancreatic ductal adenocarcinoma

Most cases of pancreatic ductal adenocarcinoma (PDAC) are lethal. Margin-negative surgical resection is a mainstay of treatment and the only chance of a cure. Differences in pathological reporting, surgical technique, definitions of resection margin, and group stratification all affect outcome analyses. Furthermore, there are controversial issues influencing the clinical interpretation of resection margin after pancreatectomy. There is no standardized definition of margin involvement in resected specimens of PDAC. The non-standardized pathologic approach explains the wide range of positive resection margin rates (13-71%) that have previously been reported. A standardized pathologic evaluation needs to be developed for proper assessment of resection margin after oncologic pancreatectomy. This manuscript reviews the current controversial issues in assessing resection margin in order to enhance understanding of the current status and potential role of pathological evaluation in patients with PDAC.

Re-evaluation of classical prognostic factors in resectable ductal adenocarcinoma of the pancreas

Pancreatic ductal adenocarcinoma carries a poor prognosis with annual deaths almost matching the reported incidence rates. Surgical resection offers the only potential cure. Yet, even among patients that undergo tumor resection, recurrence rates are high and long-term survival is scarce. Various tumor-related factors have been identified as predictors of survival after potentially curative resection. These factors include tumor size, lymph node disease, tumor grade, vascular invasion, perineural invasion and surgical resection margin. This article will re-evaluate the importance of these factors based on recent publications on the topic, with potential implications for treatment and outcome in patients with pancreatic cancer.

Comparison of Uncinate Process Cancer and Non-Uncinate Process Pancreatic Head Cancer

The special anatomical position accounts for unusual clinicopathological features of uncinate process cancer. This study aimed to compare clinicopathological features of patients with uncinate process cancer to patients with non-uncinate process pancreatic head cancer. Total 160 patients with pancreatic head cancer were enrolled and classified into two groups: uncinate process cancer and non-uncinate process pancreatic head cancer. We found that the ratio of vascular invasion was significantly higher in patients with uncinate process cancer than in patients with non-uncinate process pancreatic head cancer. In addition, the rate of R1 resection was significantly higher in patients with uncinate process cancer. Furthermore, the median disease-free survival (11 months vs. 15 months, p=0.043) and overall survival (15 months vs. 19 months, p=0.036) after R0 resection were lower for uncinate process cancer. Locoregional recurrence was more frequent (p=0.017) and earlier (12 months vs. 36 months; p=0.002) in patients with uncinate process cancer than in patients with non-uncinate process pancreatic head cancer. In conclusion, uncinate process cancer is more likely to invade blood vessel and has worse prognosis due to the earlier and more frequent locoregional recurrence.

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

BACKGROUND

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

STUDY DESIGN

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

RESULTS

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

CONCLUSIONS

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

Advances in the Surgical Management of Resectable and Borderline Resectable Pancreas Cancer

Successful surgical resection offers the only chance for cure in patients with pancreatic cancer. However, pancreatic resection is feasible in less than 20% of the patients. In this review, the current state of surgical management of pancreatic cancer is discussed. The definition of resectability based on cross-sectional imaging and the technical aspects of surgery, including vascular resection and/or reconstruction, management of aberrant vascular anatomy and extent of lymphadenectomy, are appraised. Furthermore, common pancreatic resection-specific postoperative complications and their management are reviewed.

Superior Mesenteric Artery Margin of Posttherapy Pancreaticoduodenectomy and Prognosis in Patients With Pancreatic Ductal Adenocarcinoma

Negative-margin resection is crucial to favorable prognosis in patients with pancreatic ductal adenocarcinoma. However, the definition of a negative superior mesenteric artery margin (SMAM) varies. The College of American Pathologists defines positive SMAM as the presence of tumor cells at the margin, whereas the European protocol is based on a 1 mm clearance. In this study, we examined the prognostic significance of the SMAM distance in 411 consecutive pancreatic ductal adenocarcinoma patients who completed neoadjuvant therapy and pancreaticoduodenectomy. Per College of American Pathologists criteria, 32 (7.8%) had positive margins, and 379 (92.2%) had negative margins. Among margin-negative group, SMAM was ≤ 1, 1.0 to 5.0, and >5.0 mm in 66, 145, and 168 patients, respectively. There was no difference in either disease-free survival (DFS) or overall survival (OS) between the positive-margin group and SMAM ≤ 1 mm (P > 0.05). However, patients with SMAM 1.0 to 5.0 mm had better OS than those with positive margins or SMAM ≤ 1 mm (P = 0.02). Patients with SMAM > 5.0 mm had better DFS and OS than those with SMAM 1.0 to 5.0 mm and those with positive margins or SMAM ≤ 1 mm (P < 0.01). By multivariate analysis, the SMAM distance, tumor differentiation, lymph node metastasis, and histopathologic tumor response grade were independent prognostic factors for both DFS and OS. SMAM distance correlated with lower ypT and AJCC stages, smaller tumor size, better histopathologic tumor response grade, fewer lymph node metastases, and recurrences (P < 0.05). Thus our results strongly support use of SMAM > 1 mm for R0 resection in posttherapy pancreaticoduodenectomy specimens.

The importance of surgical margins in pancreatic cancer

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

Preoperative ultrasound ablation for borderline resectable pancreatic cancer: A report of 30 cases

BACKGROUND AND OBJECTIVES

Currently, extended resection and preoperative neoadjuvant chemotherapy are the two main modalities for improvement of the resection rate and R0 resection rate of borderline resectable pancreatic cancer. The past few years, however, have witnessed some progress in the treatment of unresectable pancreatic cancer with high intensity focused ultrasound (HIFU). The aim of this study is twofold: first, to evaluate the feasibility and safety of HIFU ablation as a preoperative adjuvant therapy for borderline resectable pancreatic cancer, and second, to conduct pathological analyses to verify the safety and effectiveness of HIFU treatment of pancreatic cancer.

METHODS

From January 2011 to December 2012, 30 patients with borderline resectable pancreatic cancer underwent HIFU ablation by Haifu Model-JC200 Focused Ultrasound Tumor Therapeutic System prior to radical surgery. The effect of pre-operative HIFU ablation was evaluated by post-HIFU functional imaging results, operation time of radical surgery, blood loss volume, R0 resection rate, postoperative 1-year survival rate and Ca199 curve. Postoperative pathological specimens were obtained for histological examination.

RESULTS

All 30 patients with borderline resectable pancreatic cancer had completed the treatments and follow-ups. Functional image assessment after HIFU treatment showed a mean tumor ablation rate of (61.5±24.3)%. 28 patients underwent radical resection of pancreatic cancer 7-9 days after HIFU treatment (23 cases underwent pancreaticoduodenectomy. 4 patients underwent pancreatectomy and 1 patient had total pancreatectomy). 7 patients underwent combined resection and reconstruction of portal-superior mesenteric vein (23.3%), with the resectability rate of 93.3%, the R0 resection rate of 92.7%, and the 1-year survival rate of 96.7%. The biological coagulative necrosis regions identified by the postoperative pathological examination matched well with the necrosis foci identified by post-operative functional imaging.

CONCLUSION

The effectiveness of HIFU ablation of pancreatic tumors, as well as interstitial tissues within he main vascular spaces was confirmed by post-operative pathological examinations. Based on these observations, we conclude that preoperative HIFU ablation of borderline resectable pancreatic cancer can significantly improve the resection rate, R0 resection rate, and reduce the difficulty and risk of surgery. Therefore, HIFU may be a valuable pre-operative adjunct therapy for resectable pancreatic cancer. However, the safety and the efficacy on the improvement of the surgery need to established with future multicenter, randomized studies.

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

BACKGROUND AND OBJECTIVES

The aim of this study was to assess the overall survival (OS) after R0/R1 resections in patients with pancreatic ductal adenocarcinoma (PDAC) of the pancreatic head after implementation of a standardized histopathologic protocol (Leeds Pathology Protocol, LEEPP).

METHODS

One hundred and twenty-five patients underwent surgical resection because of PDAC of the pancreatic head. Patients were histopathologically examined according to a standardized protocol. Their oncologic outcome and clinicopathologic data were compared with those of a patient group before implementation of the LEEPP (n = 116).

RESULTS

The R1 rate increased significantly from 13 to 52 %. There was no significant difference in OS between R0 and R1 resections. The median OS in patients with a tumor clearance of less than 2 mm from the resection margin was 15.1 months (12.1-18.1 months) versus 22.2 months (7.8-36.7 months) (P = 0.046). Multivariate analysis revealed a margin clearance or 2 mm and more as an independent prognosticator for OS.

CONCLUSIONS

With applying the LEEPP, there was still no significant correlation between the R-status and OS in patients with PDAC. However, since a margin clearance of 2 mm or more is a predictive factor for OS, the R1 definition might have to be adapted in PDAC.

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.

Mesopancreas: A boundless structure, namely the rationale for dissection of the paraaortic area in pancreaticoduodenectomy for pancreatic head carcinoma

This review highlights the rationale for dissection of the 16a2 and 16b1 paraaortic area during pancreaticoduodenectomy (PD) for carcinoma of the head of the pancreas. Recent advances in surgical anatomy of the mesopancreas indicate that the retropancreatic area is not a single entity with well defined boundaries but an anatomical site of embryological fusion of peritoneal layers, and that continuity exists between the neuro lymphovascular adipose tissues of the retropancreatic and paraaortic areas. Recent advances in surgical pathology and oncology indicate that, in pancreatic head carcinoma, the mesopancreatic resection margin is the primary site for R1 resection, and that epithelial-mesenchymal transition-related processes involved in tumor progression may impact on the prevalence of R1 resection or local recurrence rates after R0 surgery. These concepts imply that mesopancreas resection during PD for pancreatic head carcinoma should be extended to the paraaortic area in order to maximize retropancreatic clearance and minimize the likelihood of an R1 resection or the persistence of residual tumor cells after R0 resection. In PD for pancreatic head carcinoma, the rationale for dissection of the paraaortic area is to control the spread of the tumor cells along the mesopancreatic resection margin, rather than to control or stage the nodal spread. Although mesopancreatic resection cannot be considered “complete” or “en bloc”, it should be “extended as far as possible” or be “maximal”, including dissection of 16a2 and 16b1 paraaortic areas.

Resection margins in pancreatic cancer

The R1 rate and prognostic significance of microscopic margin involvement differ consistently between published series. This divergence results from a lack of consensus regarding various aspects of margin status assessment. Central to the controversies is the lack of clarity about what 'R1' exactly stands for. The current UICC definition--residual microscopic tumor--is possibly too general and invites divergent interpretations. Adherence to different diagnostic criteria for microscopic margin involvement and divergent terminology for the various margins of pancreatoduodenectomy specimens add to the confusion. Furthermore, recent studies demonstrated that the dissection technique and extent of tissue sampling influence the accuracy of margin assessment. Axial specimen slicing, extensive tissue sampling, and multicolored margin inking result in a significantly higher, more accurate R1 rate than when using traditional grossing techniques. Only when international consensus on these various aspects is reached will pathology data on margin involvement be reliable and can multicenter clinical trials produce compelling evidence that allows improved pancreatic cancer treatment.