R0 in Pancreatic Cancer Surgery: Surgery, Pathology, Biology, or Definition Matters?

Perineural invasion in pancreatic cancer: Current biological function in R status, prognosis, and pain

Pancreatic ductal adenocarcinoma (PDAC) is predicted to become the second leading cause of death in 2030 and it is characterized by poor prognosis, recurrence and resistance to therapies. Several factors contribute to the complexity of this disease, among those the invasion of nerves by PDAC cells. This condition, defined as perineural invasion (PNI), is responsible of PDAC progression and pain generation. To date, PNI emerges as a hallmark feature of PDAC, showing the same oncological weight of lymph node metastasis in terms of prognosis. Targeting PNI could help improve prognosis and pain relief in PDAC patients. Only recently, a severity scoring system has been proposed to quantify PNI in histological samples although prospective validation and standardization are strongly advocated. More information about peripancreatic soft tissue infiltration and a "true" curative surgery could be found in understanding the molecular mechanisms of PNI. The incorporation of PNI markers for grading mesopancreas and retroperitoneal invasion is required to overcome current limitations of the histological workup. We discuss the modern understanding of PNI in PDAC, and the state of the art in clinical setting. Although there are still a lot to learn about PDAC, PNI represents one of the biological detonators and an important focus of future research.

Currently Debated Topics on Surgical Treatment of Pancreatic Ductal Adenocarcinoma: A Narrative Review on Surgical Treatment of Borderline Resectable, Locally Advanced, and Synchronous or Metachronous Oligometastatic Tumor

BACKGROUND

Previously considered inoperable patients (borderline resectable, locally advanced, synchronous oligometastatic or metachronous pancreatic adenocarcinoma (PDAC)) are starting to become resectable thanks to advances in chemo/radiotherapy and the reduction in operative mortality.

METHODS

This narrative review presents a chosen literature selection, giving a picture of the current state of treatment of these patients.

RESULTS

Neoadjuvant therapy (NAT) is generally recognized as the treatment of choice before surgery. However, despite the increased efficacy, the best pathological response is still limited to 10.9-27.9% of patients. There are still limited data on the selection of possible NAT responders and how to diagnose non-responders early. Multidetector computed tomography has high sensitivity and low specificity in evaluating resectability after NAT, limiting the resection rate of resectable patients. Ca 19-9 and Positron emission tomography are giving promising results. The prediction of early recurrence after a radical resection of synchronous or metachronous metastatic PDAC, thus identifying patients with poor prognosis and saving them from a resection of little benefit, is still ongoing, although some promising data are available.

CONCLUSION

In conclusion, high-level evidence demonstrating the benefit of the surgical treatment of such patients is still lacking and should not be performed outside of high-volume centers with interdisciplinary teams of surgeons and oncologists.

Prevalence of pancreatic exocrine insufficiency after pancreatic surgery measured by 13C mixed triglyceride breath test: A prospective cohort study

BACKGROUND

Patients undergoing pancreatic surgery are at risk of pancreatic exocrine insufficiency (PEI) and needing pancreatic enzyme replacement therapy (PERT).

METHODS

This study included 254 patients undergoing pancreatic surgery for oncologic indications. A13C mixed triglyceride breath test was performed immediately preoperative and postoperative. This test analyzes the pancreatic remnant lipase activity measuring 13CO2 in breath samples after a test meal with 1.3-distearyl-(13C-Carboxyl)octanol-glycerol. Cumulative percent dose recovery after 6 h of less than 23% confirms PEI. In addition, PEI was compared between pathology subgroups.

RESULTS

In 197 patients undergoing pancreaticoduodenectomy, cPDR-6h decreased significantly from a median of 32.84% before to 15.80% after surgery (p < 0.0001). This decrease in exocrine function was significant in all pathology subgroups except in pancreatic neuroendocrine tumors. Exocrine function decreased most in pancreatic ductal adenocarcinoma (PDAC). In addition, the percentage of patients needing PERT because of PEI increased from 25.9% to 68.0% postoperative (p < 0.001). Overall, patients with an MPD diameter of more than 3 mm had a higher risk of developing postoperative PEI: 62.7% compared to 37.3% (p = 0.009), OR = 3.11. In contrast, the majority of the 57 patients undergoing a distal pancreatectomy did not experience any significant change in exocrine function.

CONCLUSIONS

The vast majority of patients undergoing pancreaticoduodenectomy for oncologic indications experience a significant drop in exocrine function, are at high risk of developing pancreatic exocrine insufficiency and consequently need to be treated with pancreatic enzyme replacement therapy. Therefore, systematic screening for pancreatic exocrine insufficiency is needed after pancreaticoduodenectomy.

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 role of intraoperative radiation therapy in resectable pancreatic cancer: a systematic review and meta-analysis

PURPOSE

Several studies investigating the role of intraoperative radiotherapy (IORT) in the treatment of resectable pancreatic cancer (PC) have been published; however, their results remain inconsistent. By conducting a systematic review and meta-analysis, this study aimed to compare clinical outcomes in patients with resectable PC who underwent surgery with or without IORT.

METHODS AND MATERIALS

The MEDLINE/PubMed, EMBASE, and Cochrane Library databases were searched to identify relevant studies published up to February 28, 2019. The main outcome measures included median survival time (MST), local recurrence (LR), postoperative complications, and operation-related mortality. Pooled effect estimates were obtained by performing a random-effects meta-analysis.

RESULTS

A total of 1095 studies were screened for inclusion, of which 15 studies with 834 patients were included in the meta-analysis. Overall, 401 patients underwent pancreatic resection with IORT and 433 underwent surgery without IORT. The pooled analysis revealed that IORT group experienced favorable overall survival (median survival rate [MSR], 1.20; 95% confidence interval [CI], 1.06-1.37, P = 0.005), compared with patients who did not receive IORT. Additionally, the pooled data showed a significantly reduced LR rate in the IORT group compared with that in the non-IORT group (relative risk [RR], 0.70; 95% CI, 0.51-0.97, P = 0.03). The incidences of postoperative complications (RR, 0.95; 95% CI, 0.73-1.23) and operation-related mortality (RR, 1.07; 95% CI, 0.44-2.63) were similar between the IORT and non-IORT groups.

CONCLUSION

IORT significantly improved locoregional control and overall survival in patients with resectable PC, without increasing postoperative complications and operation-related mortality rates.

Robotic radical antegrade modular pancreatosplenectomy (RAMPS) versus standard retrograde pancreatosplenectomy (SRPS): study protocol for a randomized controlled trial

Background

Data from meta-analysis suggest that robotic radical antegrade modular pancreatosplenectomy (RAMPS) is a safe and effective procedure for treating adenocarcinoma in the body or tail of the pancreas, and is oncologically superior to standard retrograde pancreatosplenectomy (SRPS). RAMPS is an operation that actively expands the scope of resection, and achieves a higher R0 resection rate and lymph nodes acquisition through expanded resection. However, previous studies on RAMPS were conducted under open and laparoscopic surgery. Robotic surgery, on the other hand, plays a role in ergonomics and offers several advantages, including less fatigue, tremor filtering, 7° of wrist-like motion, motion scaling, and three-dimensional vision. At present, there is still a world-wide lack of clinical studies to observe the safety and clinical efficacy of robotic RAMPS. Hence, prospective randomized controlled trials (RCTs) comparing robotic RAMPS and SRPS are required. We begin an RCT to compare short-term surgical and oncological outcomes of robotic RAMPS and SRPS in patients undergoing distal pancreatectomy.

Methods

This is a randomized, single-center clinical trial. All participants are adult patients with primary pancreatic cancer, who are undergoing RAMPS or SRPS. The primary endpoints are R0 rate (resection margins are classified by a margin to tumor distance ≥ 1 mm). The secondary endpoints are the number of harvested lymph nodes, perioperative complications and perioperative indicators (duration of surgery, blood loss, blood transfusion volume, costs).

Discussion

We are undertaking a prospective RCT to evaluate the surgical and oncological outcomes of robotic RAMPS. This procedure may become a standard approach to robotic pancreatosplenectomy.

Trial registration

Chinese Clinical Trial Registry: ChiCTR1900020833, Registered on 20 January 2019.

Clinical impact of additional therapy for residual pancreatic cancer

PURPOSE

This study aimed to explore the prognostic significance of the resection margin (R) status of pancreatic ductal adenocarcinoma (PDAC) patients receiving neoadjuvant therapy (NAT) or adjuvant chemotherapy (AC).

METHODS

We retrospectively reviewed 427 consecutive patients, and the overall survival (OS) and disease-free survival (DFS) were analyzed based on the R status by a propensity score analysis (PSA).

RESULTS

The R0 ratio of the NAT (+) group was significantly higher than that of the NAT (-) group (97.2% vs. 69.6%, P < 0.0001). Local recurrence was well controlled in the NAT (+) group compared to the NAT (-) group (15.3% vs. 34.1%, P = 0.0013). The PSA revealed no significant survival difference between R0 and R1 resection among those treated with AC (median survival time [MST]: 43.0 vs. 33.3 months, matching hazard ratio [HR]: 1.212, P = 0.5708). Furthermore, the DFS in R0 and R1 resection followed by AC was identical (MST: 20.6 vs. 17.7 months, matching HR: 1.020, P = 0.9482).

CONCLUSIONS

NAT was a significant predictor of R0 resection. When patients completed AC, there were no marked differences in the OS or DFS between R0 and R1 resection. Our results demonstrated that the clinical impact of the R1 status has waned in the current era of PDAC management.

MAPLE-PD trial (Mesenteric Approach vs. Conventional Approach for Pancreatic Cancer during Pancreaticoduodenectomy): study protocol for a multicenter randomized controlled trial of 354 patients with pancreatic ductal adenocarcinoma

Background

The mesenteric approach is an artery-first approach to pancreaticoduodenectomy for pancreatic cancer, which starts with the dissection of connective tissues around the superior mesenteric artery. The procedure aims for early confirmation of resectability by checking the surgical margin around the superior mesenteric artery first during the operation. It also aims to decrease intraoperative blood loss by early ligation of the inferior pancreaticoduodenal artery and to increase R0 rate by complete clearance of the lymph nodes around the superior mesenteric artery and pancreatic head plexus II, the most favorable positive margin site for pancreatic ductal adenocarcinoma. Furthermore, it aims to avoid the spread of cancer cells during operation (nontouch isolation technique). The MAPLE-PD (Mesenteric Approach vs. Conventional Approach for Pancreatic Cancer during Pancreaticoduodenectomy) trial investigates whether the mesenteric approach can prolong the survival of patients with pancreatic ductal adenocarcinoma who undergo pancreaticoduodenectomy compared with the conventional approach.

Methods/design

The MAPLE-PD trial is a Japanese multicenter randomized controlled trial that compares the surgical outcomes between the mesenteric and conventional approaches to pancreaticoduodenectomy. Patients with pancreatic ductal adenocarcinoma scheduled to undergo pancreaticoduodenectomy are randomized before operation to either a conventional approach (arm A) or a mesenteric approach (arm B). In arm A, the operation starts with Kocher’s maneuver. At the final step of the removal procedure, the connective tissues around the superior mesenteric artery are dissected. In arm B, the operation starts with dissection of the connective tissues around the superior mesenteric artery and ends with Kocher’s maneuver. In total, 354 patients from 15 Japanese high-volume centers will be randomized. The primary endpoint is overall survival by intention-to-treat analysis. Secondary endpoints include intraoperative blood loss, R0 rate, and recurrence-free survival.

Discussion

If the MAPLE-PD trial shows the oncological benefits of the mesenteric approach for patients with pancreatic ductal adenocarcinoma, this procedure may become a standard approach to pancreaticoduodenectomy.

Trial registration

ClinicalTrials.gov, NCT03317886. Registered on 23 October 2017.

University Hospital Medical Information Network Clinical Trials Registry, UMIN000029615. Registered on 15 January 2018.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-3002-z) contains supplementary material, which is available to authorized users.

Clinical impact of margin status on survival and recurrence pattern after curative-intent surgery for pancreatic cancer

BACKGROUND/OBJECTIVE

The definition of R0 resection for invasive pancreatic ductal carcinoma (IPDC) is important. However, there are different definitions among several countries in the world.

METHODS

From 2001 to 2015, 100 consecutive patients with IPDC who underwent pancreatic resection in our hospital were enrolled. We compared survival and recurrence patterns between the R0 group and R1 group based on the UICC (Union for International Cancer Control) classification (current-R0 vs. current-R1) and based on our revised classification, which defines R0 as a surgical margin of >1 mm (revised-R0 vs. revised-R1).

RESULTS

The 100 patients comprised 58 males and 42 females, and their median age was 70 [32-87]. There were 84 patients in the current-R0 group and 43 in the revised-R0 group. There was no difference in overall survival (OS) or recurrence-free survival (RFS) between the current-R0 group and current-R1 group. However, there was a tendency toward a higher OS rate in the revised-R0 than revised-R1 group (log-rank p = 0.065), and RFS was significantly better in the revised-R0 than revised-R1 group (log-rank p = 0.002). There was no significant difference in the recurrence patterns between the current-R0 and current-R1 groups. In contrast, the local recurrence rate was significantly lower in the revised-R0 than revised-R1 group (21% vs. 42%, respectively; p = 0.026).

CONCLUSION

The revised classification of surgical resection may be more useful than the current UICC classification for prediction of prognosis and local recurrence of IPDC.

Mesenteric approach during pancreaticoduodenectomy for pancreatic ductal adenocarcinoma

Mesenteric approach is an artery‐first approach during pancreaticoduodenectomy (PD). In the present study, we evaluated clinical and oncological benefits of this procedure for pancreatic ductal adenocarcinoma (PDAC) of the pancreas head. Between 2000 and 2015, 237 consecutive PDAC patients underwent PD. Among them, 72 experienced the mesenteric approach (mesenteric group) and 165 the conventional approach (conventional group). A matched‐pairs group consisted of 116 patients (58 patients in each group) matched for age, gender, resectability status, and neoadjuvant therapy. Surgical and oncological outcomes were compared between the two groups in unmatched‐ and matched‐pair analyses. Intraoperative blood loss was lower in the mesenteric group than in the conventional group in both resectable PDAC (R‐PDAC) and borderline resectable PDAC (BR‐PDAC) on unmatched‐ and matched‐pairs analyses (R‐PDAC, unmatched: 312.5 vs 510 mL, P=.008; matched: 312.5 vs 501.5 mL, P=.023; BR‐PDAC, unmatched: 507.5 vs 935 mL, P<.001; matched: 507.5 vs 920 mL, P=.003). Negative surgical margins (R0) and overall survival (OS) rates in the mesenteric group were better in R‐PDAC patients (R0 rates, unmatched: 100% vs 87.7%, P=.044; matched: 100% vs 86.7%, P=.045; OS, unmatched: P=.008, matched: P=.021), although there were no significant differences in BR‐PDAC patients. Mesenteric approach might reduce blood loss by early ligation of the vessels to the pancreatic head. Furthermore, it might increase R0 rate, leading to improvement of survival for R‐PDAC patients. However, R0 and survival rates could not be improved only by the mesenteric approach for BR‐PDAC patients. Therefore, effective multidisciplinary treatment is essential to improve survival in BR‐PDAC patients.

Technical Details of an Anterior Approach to the Superior Mesenteric Artery During Pancreaticoduodenectomy

INTRODUCTION

Use of central vascular ligation during dissection around the superior mesenteric artery (SMA) in pancreaticoduodenectomy (PD) for periampullary malignancies has rarely been documented.

METHODS

We developed the SMA hanging technique (SHT) to facilitate central vascular ligation during PD. Briefly, SMA dissection was initiated using the supracolic anterior approach, followed by left-sided dissection. The SMA was taped under finger guidance immediately after right-sided dissection. The ligament of Treitz was detached from the SMA during left-sided dissection, facilitating adequate lymph node dissection while preserving the nerve plexus around the SMA. Forty-seven consecutive patients who underwent PD for periampullary malignancies were divided into two groups: 23 underwent SHT and 24 underwent conventional dissection. Patients' clinical results were assessed to evaluate the feasibility and validity of SHT.

RESULTS

Blood loss volume, operation duration, and the incidence of bleeding during SMA dissection were significantly lower in the SHT group than in the conventional group. The short-term and oncological results were similarly acceptable in both groups.

CONCLUSIONS

SHT is a feasible and safe technique with acceptable short-term outcomes. We propose the use of this procedure to standardize en bloc dissection around the SMA.

Microscopic Residual Tumor After Pancreaticoduodenectomy: Is Standardization of Pathological Examination Worthwhile?

OBJECTIVES

R1 resection rate after pancreaticoduodenectomy (PD) for cancer is highly variable. The aim of this study was to verify if a standardized histopathological work-up of the specimen affects the rate of R1 resection after PD for cancer.

METHODS

Two groups of specimens were managed with (standardized method [SM] group) or without (non-standardized method [NSM] group) a SM of histopathological work-up. Each group included 50 cases of PD for periampullary cancer. Differences in terms of R1 resection rate between the 2 groups were evaluated. Correlation between R1 status and local recurrence was also evaluated.

RESULTS

The cohort of 100 patients consisted of 66 pancreatic ductal adenocarcinoma, 15 cholangiocarcinoma, and 19 ampullary cancer. The R1 resection rate resulted statistically higher in the SM group (66% vs 10%). Local recurrence was more frequently related to R1 resection in the SM group (34.3% of cases) than in NSM group (20% of cases).

CONCLUSIONS

The use of the SM of pathological evaluation of the specimen after PD for cancer determines a significant increase of R1 resection. This remarkable difference seems to be due to the different definition of minimum clearance. The SM seems to better discriminate patients in terms of risk of local recurrence.

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.

Outcomes of resections for pancreatic adenocarcinoma with suspected venous involvement: a single center experience

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) patients frequently present with borderline resectable disease, which can be due to invasion of the portal/superior mesenteric vein (PV/SMV). Here, we analyzed this group of patients, with emphasis on short and long-term outcomes.

METHODS

156 patients who underwent a resection for PDAC were included in the analysis and sub-stratified into a cohort of patients with PV/SMV resection (n = 54) versus those with standard surgeries (n = 102).

RESULTS

While venous resections could be performed safely, there was a trend towards shorter median survival in the PV/SMV resection group (22.7 vs. 15.8 months, p = 0.157). These tumors were significantly larger (3.5 vs. 4.3 cm; p = 0.026) and margin-positivity was more frequent (30.4% vs. 44.4%, p = 0.046).

CONCLUSION

Venous resection was associated with a higher rate of margin positivity and a trend towards shorter survival. However, compared to non-surgical treatment, resection offers the best chance for long term survival.

Distribution and pathological features of pancreatic, ampullary, biliary and duodenal cancers resected with pancreaticoduodenectomy

BACKGROUND

Pancreatic cancer (PC) has the worst survival of all periampullary cancers. This may relate to histopathological differences between pancreatic cancers and other periampullary cancers. Our aim was to examine the distribution and histopathologic features of pancreatic, ampullary, biliary and duodenal cancers resected with a pancreaticoduodenectomy (PD) and to examine local trends of periampullary cancers resected with a PD.

METHODS

A retrospective review of PD between January 2000 and December 2012 at a public metropolitan database was performed. The institutional ethics committee approved this study.

RESULTS

There were 142 PDs during the study period, of which 70 cases were pre-2010 and 72 post-2010, corresponding to a recent increase in the number of cases. Of the 142 cases, 116 were for periampullary cancers. There were also proportionately more PD for PC (26/60, 43% pre-2010 vs 39/56, 70% post-2010, P = 0.005). There were 65/116 (56%) pancreatic, 29/116 (25%), ampullary, 17/116 (15%) biliary and 5/116 (4%) duodenal cancers. Nodal involvement occurred more frequently in PC (78%) compared to ampullary (59%), biliary (47%) and duodenal cancers (20%), P = 0.002. Perineural invasion was also more frequent in PC (74%) compared to ampullary (34%), biliary (59%) and duodenal cancers (20%), P = 0.002. Microvascular invasion was seen in 57% pancreatic, 38% ampullary, 41% biliary and 20% duodenal cancers, P = 0.222. Overall, clear margins (R0) were achieved in fewer PC 41/65 (63%) compared to ampullary 27/29 (93%; P = 0.003) and biliary cancers 16/17 (94%; P = 0.014).

CONCLUSIONS

This study highlights that almost half of PD was performed for cancers other than PC, mainly ampullary and biliary cancers. The volume of PD has increased in recent years with an increased proportion being for PC. PC had higher rates of nodal and perineural invasion compared to ampullary, biliary and duodenal cancers.

Pancreatic adenocarcinoma with venous involvement: is up-front synchronous portal-superior mesenteric vein resection still justified? A survey of the Association Française de Chirurgie

BACKGROUND

Venous resection (VR) during pancreatectomy has been reported to neither increase mortality nor morbidity and to provide similar survival outcomes in same stage tumors. However, controversy remains regarding the indications for up-front surgery according to the degree of venous involvement.

METHODS

From 2004 to 2009, 1,399 patients included in a French multicenter survey underwent pancreaticoduodenectomy or total pancreatectomy for pancreatic adenocarcinoma, either without VR (997 standard resections [SR]) or with VR (402 patients; 29 %). Postoperative and long-term outcomes were compared in both groups.

RESULTS

VR was associated with the following factors: larger tumors (p < 0.001), poorly differentiated tumors (p = 0.004), higher numbers of positive lymph nodes (p = 0.042), and positive resection margins (R1; p < 0.001). Overall, VR increased neither postoperative morbidity nor postoperative mortality (5 vs. 3 % in SR patients; p = 0.16). The median and 3-year survival rates in VR patients versus SR patients were 21 months and 31 % vs. 29 months and 44 %, respectively (p = 0.0002). In the entire cohort, multivariate analysis identified VR as a significant poor prognostic factor for long-term survival (hazard ratio [HR] 1.75, 95 % confidence interval [CI] 1.28-2.40; p = 0.0005). In the VR patients, lymph node ratio, whatever the cutoff (<0.3: p = 0.093; ≥ 0.3: p = 0.0098), R1 resection (p = 0.010), and segmental resection (p = 0.016) were independent risk factors; neoadjuvant treatment (HR 0.52, 95 % CI 0.29-0.94; p = 0.031) and adjuvant treatment (HR 0.55, 95 % CI 0.35-0.85; p = 0.006) were significantly associated with improved long-term survival.

CONCLUSIONS

Long-term survival after pancreatectomy was significantly altered when up-front VR was performed. Neoadjuvant treatment may be a better strategy than up-front resection in patients with preoperative suspicion of venous involvement.

Outcome of superior mesenteric-portal vein resection during pancreatectomy for borderline ductal adenocarcinoma: results of a prospective comparative study

BACKGROUND

Approximately 20 % of patients affected by pancreatic ductal adenocarcinoma are amenable to surgical resection. Several tumours are reported as "borderline resectable" because of their proximity to the major vessels. In the effort to achieve a radical tumour removal, vein resection has been proposed, but its oncological benefits remain debated.

METHODS

Our aim is to investigate morbidity, mortality and survival after pancreatectomy with vein resection.

RESULTS

Forty patients underwent pancreatectomy and vein resection (group A), and 20 patients (group B) underwent bilio-enteric and/or gastro-entero bypass. In group A, cancer vein invasion was microscopically proven in 14 cases (35 %). Vein infiltration, tumour differentiation and node-positive disease were not adverse prognostic variables. No difference in survival was seen over a 1-year follow-up. After this period, group A showed significant survival benefits with a longer stabilisation of the disease (p = 0.005). Tumour-free resection margins and adjuvant chemoradiotherapy were the most important prognostic factors (p < 0.05).

CONCLUSIONS

Suspicion of vein infiltration should not be a contraindication to resection. Pancreatectomy can be safely performed with an acceptable morbidity and better survival trend.

Pancreaticoduodenectomy for pancreatic ductal adenocarcinoma: a French multicentre prospective evaluation of resection margins in 150 evaluable specimens

OBJECTIVES

This study aimed to determine the impact of a standardized pathological protocol on resection margin status after pancreaticoduodenectomy (PD) for ductal adenocarcinoma.

METHODS

A total of 150 patients operated during 2008-2010 were included in a prospective multicentre study using a 'quality protocol'. Multicolour inking by the surgeon identified three resection margins: the portal vein-superior mesenteric vein margin (PV-SMVm) or mesenterico-portal vein groove; the superior mesenteric artery margin (SMAm), and the posterior margin. Resection margins were stratified by 0.5-mm increments (range: 0-2.0 mm). Pancreatic neck, bile duct and intestinal margins were also analysed. Correlations between histopathological factors and survival in the 0-mm resection margin group were analysed.

RESULTS

Thirty-six patients (24%) had a PV-SMV resection (PV-SMVR). An analysis of resections categorized according to margin distances of 0 mm, <1.0 mm, <1.5 mm and <2.0 mm confirmed R1 resections in 35 (23%), 91 (61%), 94 (63%) and 107 (71%) patients, respectively. The most frequently invaded resection margin was the PV-SMVm (35% of all patients) and PV-SMVR was the only factor correlated with a higher risk for at least one 0-mm positive resection margin on multivariate analysis (P < 0.001). Two-year progression-free survival (PFS) and median PFS time in patients with R0 and R1 resections (at 0 mm), respectively, were 42.0% and 26.5%, and 19.5 months and 10.5 months, respectively (P = 0.02). A positive PV-SMVm and SMAm had significant impact on PFS, whereas a positive posterior margin had no impact.

CONCLUSIONS

Pancreaticoduodenectomy requiring PV-SMVR was associated with a higher risk for R1 resection. The standardization of histopathological analysis has a clinically relevant impact on PFS data.

Role of endoscopic ultrasound in treatment of pancreatic cancer

Endoscopic ultrasound (EUS) can help diagnose diseases with high accuracy because it overcomes the limitations of gastrointestinal gas and abdominal fat. The emergence of curved linear-array echoendoscopy has significantly promoted the applications of the technique to new levels. The advancement has appeared from EUS imaging to EUS-guided fine needle aspiration, drainage and injection. Computed tomography and magnetic resonance imaging present certain limitations for diagnosing pancreatic tumors due to the specificity of the location of such growths. In addition, traditional chemotherapy does not show ideal results because pancreatic cancer (PC) exhibits hypovascular characteristics. Interventional EUS can overcome these limitations and has potential to become the mainstream method of PC local treatment in the future. This paper reviews the use of interventional EUS in the treatment of PC based on previous studies.

Is it time to stop checking frozen section neck margins during pancreaticoduodenectomy?

BACKGROUND

Residual disease after pancreaticoduodenectomy (PD) for pancreatic adenocarcinoma (PDAC) adversely impacts survival. The value of taking additional neck margin after a positive frozen section (FS) to achieve a negative margin remains uncertain.

METHODS

All patients who underwent PD for PDAC from January 2000 August 2012 were identified and classified as negative (R0) or positive (R1) based on final neck margin. We examined factors for association with a positive FS neck margin and overall survival (OS). We assessed the value of converting an R1 neck margin to R0 via additional parenchymal resection.

RESULTS

A total of 382 patients had FS neck margin analysis, of which 53 (14 %) were positive. Positive FS neck margin was associated with decreased OS (11.1 vs. 17.3 months, p = 0.01) on univariate analysis. On multivariate analysis poor histologic grade (p = 0.007), increased tumor size (p = 0.003), and a positive retroperitoneal margin (p = 0.009) were independently associated with decreased OS, but positive FS neck margin was not. Of the 53 patients with positive FS, 41 underwent additional neck resection and 23 were converted to R0. On permanent section, R0 neck margin was achieved in 322 patients (84 %), R1 in 37 patients (10 %), and R1 converted to R0 in 23 patients (6 %). Both the converted and the R1 groups had significantly poorer OS than the R0 group (11.3 vs. 11.1 vs. 17.3 months respectively; p = 0.04).

CONCLUSIONS

Positive FS margin at the pancreatic neck during PD for PDAC is associated with poor survival. Extending the neck resection after a positive FS to achieve R0 margin status does not appear to improve OS.

Comparative analysis of traditional and coiled fiducials implanted during EUS for pancreatic cancer patients receiving stereotactic body radiation therapy

BACKGROUND

EUS-guided fiducial placement facilitates image-guided radiation therapy (IGRT).

OBJECTIVE

To compare 2 types of commercially available fiducials for technical success, complications, visibility, and migration.

DESIGN

Retrospective, single-center, comparative study.

SETTING

Tertiary-care medical center.

INTERVENTIONS

Traditional fiducials (TFs) (5-mm length, 0.8-mm diameter) and Visicoil fiducials (VFs) (10-mm length, 0.35-mm diameter) were compared. Fiducials were placed using linear 19-gauge (for TFs) or 22-gauge (for VFs) needles. A subjective visualization scoring system (0-2; 0 = not visible, 1 = barely visible, 2 = clearly visible) was used to assess visibility on CT. Fiducial migration was calculated as a change in interfiducial distance.

MAIN OUTCOME MEASUREMENTS

Technical success, complications, visibility, and migration of 2 types of fiducials.

RESULTS

Thirty-nine patients with locally advanced pancreatic cancer underwent EUS-guided placement of 103 fiducials (77 TFs, 26 VFs). The mean number of fiducials placed per patient was 2.66 (standard deviation 0.67) for the 19-gauge needle and 2.60 (standard deviation 0.70) for the 22-gauge needle (P = .83). No intra- or postprocedural complications were encountered. The median visibility score for TFs was significantly better than that for VFs, both when scores of 0 were and were not included (2.00, interquartile range [IQR] 2.00-2.00 vs 1.75, IQR 1.50-2.00, P = .009 and 2.00, IQR 2.00-2.00 vs 2.00, IQR 1.50-2.00, P < .0001, respectively). The mean migration was not significantly different between the 2 types of fiducials (0.8 mm [IQR 0.4-1.6 mm] for TFs vs 1.3 mm [IQR 0.6-1.5 mm] for VFs; P = .72).

LIMITATIONS

Retrospective, nonrandomized design.

CONCLUSIONS

Visibility was significantly better for TFs compared with VFs. The degree of fiducial migration was not significantly different for TFs and VFs. There was no significant difference in the mean number of fiducials placed, indicating a similar degree of technical difficulty for TF and VF deployment.

Resection margin involvement and tumour origin in pancreatic head cancer

BACKGROUND

Assessment of the origin of adenocarcinoma in pancreatoduodenectomy specimens (pancreatic, ampullary or biliary) and resection margin status is not performed in a consistent manner in different centres. The aim of this review was to identify the impact of such variations on patient outcome.

METHODS

A systematic literature search for articles on pancreatic, ampullary, distal bile duct and periampullary cancer was performed, with special attention to data on resection margin status, pathological examination and outcome.

RESULTS

The frequent reclassification of tumour origin following slide review, and the wide variation in published incidence of pancreatic (33-89 per cent), ampullary (5-42 per cent) and distal bile duct (5-38 per cent) cancers indicate that the histopathological distinction between the three cancer groups is less accurate than generally believed. Recent studies have shown that the wide range of rates of microscopic margin involvement (R1) in pancreatoduodenectomy specimens (18-85, 0-27 and 0-72 per cent respectively for pancreatic, ampullary and distal bile duct cancers) is mainly caused by differences in pathological assessment rather than surgical practice and patient selection. As a consequence of the existing inconsistency in reporting of these data items, the clinical significance of microscopic margin involvement in each of the three cancer groups remains unclear.

CONCLUSION

Inaccurate and inconsistent distinction between pancreatic, ampullary and distal bile duct cancer, combined with inaccuracies in resection margin assessment, results in obfuscation of key clinicopathological data. Specimen dissection technique plays a key role in the quality of the assessment of both tumour origin and margin status. Unless the pathological examination is meticulous and standardized, comparison of results between centres and observations in multicentre trials will remain of limited value.

Pancreatic cancer: an endoscopic perspective

Pancreatic cancer continues to be a diagnostic and therapeutic challenge. The advent of endoscopic ultrasound-guided interventions have brought about a paradigm shift in the endoscopic approach to diagnosis, treatment and palliation of this common malignancy. The last decade has witnessed significant advances in techniques of endoscopic biliary drainage, endoluminal stenting, celiac plexus neurolysis and image-guided radiation therapy, which have transformed the scope of palliation in pancreatic cancer. Moreover, endoscopic ultrasound-aided intratumoral delivery of fiducials, radioisotopes and chemotherapeutic agents have shown promising results and warrant further investigation. This review summarizes the recent advances in endoscopic applications for the management of pancreatic neoplasms.

Quantum dots in cancer therapy

INTRODUCTION

Quantum dots (QDs) are nanometer-size luminescent semiconductor nanocrystals. Their unique optical properties, such as high brightness, long-term stability, simultaneous detection of multiple signals and tunable emission spectra, make them appealing as potential diagnostic and therapeutic systems in the field of oncology.

AREAS COVERED

This paper summarizes the recent progress of promising applications of QDs in cancer therapy, from the following aspects: identifying molecular targets, sentinel lymph-node mapping, surgical oncology, drug delivery and tracking, fluorescence resonance energy transfer and photodynamic therapy, personalized and predictive medicine, and multifunctional design and development. Limitations and toxicity issues related to QDs in living organisms are also discussed.

EXPERT OPINION

Bioconjugated QDs can be used to identify potential molecular biomarkers for cancer diagnosis, treatment and prognosis. They may allow the surgeon to map sentinel lymph nodes and perform a complete surgical resection. Their unique optical properties make them ideal donors of fluorescence resonance energy transfer and photodynamic therapy studies. Multifunctional QDs have become effective materials for synchronous cancer diagnosis, targeting and treatment. For QDs, toxicity remains the major barrier to clinical translation.