Extended lymphadenectomy in the surgery of pancreatic adenocarcinoma and its relation to quality improvement issues

Extensive lymph node dissection during pancreaticoduodenectomy: a risk factor for hepatic steatosis?

PURPOSE

The first reports of hepatic steatosis following pancreaticoduodenectomy (PD) were published several years ago; however, clear risk factors remain to be identified. Therefore, the aim of this study was to identify the risk factors for hepatic steatosis post-PD.

METHODS

We studied 90 patients who had undergone PD between September 2005 and January 2015. The inclusion criteria were as follows: available unenhanced CT within one month before PD and at least one unenhanced CT acquisition between PD and chemotherapy initiation. Using scanners, we studied the liver and spleen density as well as the surface areas of visceral (VF) and subcutaneous fat (SCF). These variables were previously identified by univariate and multivariate analyses.

RESULTS

Hepatic steatosis occurred in 25.6% of patients at 45.2 days, on average, post-PD. Among the patients with hepatic steatosis, the average liver density was 52 HU before PD and 15.1 HU post-PD (p < 0.001). The Patients with hepatic steatosis lost more VF (mean, 28 vs. 11 cm²) and SCF (28.8 vs. 13.7 cm²) (p < 0.01 and p = 0.01, respectively). Portal vein resection and extensive lymph node dissection were independent risk factors in the multivariate analysis (odds ratio [OR] 5.29, p = 0.009; OR 3.38, p = 0.04, respectively).

CONCLUSION

Portal vein resection and extensive lymph node dissection are independent risk factors for post-PD hepatic steatosis.

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.

Time-related changes in the prognostic significance of the total number of examined lymph nodes in node-negative pancreatic head cancer

BACKGROUND AND OBJECTIVES

The aim of study was to assess time trends in the association between the total number of lymph nodes examined (TNLE) and survival in patients operated for adenocarcinoma of the head of pancreas.

METHODS

Patients operated for node-negative adenocarcinoma of the head of pancreas between 1988 and 2007 were identified from the Surveillance, Epidemiology and End Results (SEER) database. Patients diagnosed between 1988 and 2002 were compared to those diagnosed between 2003 and 2007.

RESULTS

A total of 3,406 patients were included. Although TNLE was associated with survival, the effect was not uniform. Compared to patients with >12 TNLE, survival decreased with lower TNLE (4-12 TNLE: hazard ratio [HR] 1.27, 95% CI 1.10-1.46; <4 TNLE: HR 1.39, 95% CI 1.20-1.60) among patients diagnosed between 1988 and 2002. In contrast, for those diagnosed between 2003 and 2007, while there was decreased survival for those with <4 nodes (HR 1.44, 95% CI 1.22-1.71), no effect was seen for patients with TNLE 4-12 (HR 0.98, 95% CI 0.85-1.14).

CONCLUSION

The prognostic significance of the TNLE in patients operated for adenocarcinoma of the head of the pancreas is not constant over time.

CXCL4L1-fibstatin cooperation inhibits tumor angiogenesis, lymphangiogenesis and metastasis

Anti-angiogenic and anti-lymphangiogenic drugs slow tumor progression and dissemination. However, an important difficulty is that a tumor reacts and compensates to obtain the blood supply needed for tumor growth and lymphatic vessels to escape to distant loci. Therefore, there is a growing consensus on the requirement of multiple anti-(lymph)angiogenic molecules to stop cell invasion efficiently. Here we studied the cooperation between endogenous anti-angiogenic molecules, endostatin and fibstatin, and a chemokine, the Platelet Factor-4 variant 1, CXCL4L1. Anti-angiogenic factors were co-expressed by IRES-based bicistronic vectors and their cooperation was analyzed either by local delivery following transduction of pancreatic adenocarcinoma cells with lentivectors, or by distant delivery resulting from intramuscular administration in vivo of adeno-associated virus derived vectors followed by tumor subcutaneous injection. In this study, fibstatin and CXCL4L1 cooperate to inhibit endothelial cell proliferation, migration and tubulogenesis in vitro. No synergistic effect was found for fibstatin-endostatin combination. Importantly, we demonstrated for the first time that fibstatin and CXCL4L1 not only inhibit in vivo angiogenesis, but also lymphangiogenesis and tumor spread to the lymph nodes, whereas no beneficial effect was found on tumor growth inhibition using molecule combinations compared to molecules alone. These data reveal the synergy of CXCL4L1 and fibstatin in inhibition of tumor angiogenesis, lymphangiogenesis and metastasis and highlight the potential of IRES-based vectors to develop anti-metastasis combined gene therapies.

Pancreatic surgery: beyond the traditional limits

Pancreatic cancer is one of the five leading causes of cancer death for both males and females in the western world. More than 85 % pancreatic tumors are of ductal origin but the incidence of cystic tumors such as intrapapillary mucinous tumors (IPMN) or mucinous cystic tumors (MCN) and other rare tumors is rising. Complete surgical resection of the tumor is the mainstay of any curative therapeutic approach, however, up to 40 % of patients with potentially resectable pancreatic cancer are not offered surgery. This is despite 5-year survival rates of up to 40 % or even higher in selected patients depending on tumor stage and histology. Standard procedures for pancreatic tumors include the Kausch-Whipple- or pylorus-preserving Whipple procedure, and the left lateral pancreatic resection (often with splenectomy), and usually include regional lymphadenectomy. More radical or extended pancreatic operations are becoming increasingly utilised however and we examine the data available for their role. These operations include major venous and arterial resection, multivisceral resections and surgery for metastatic disease, or palliative pancreatic resection. Portal vein resection for local infiltration with or without replacement graft is now well established and does not deleteriously affect perioperative morbidity or mortality. Arterial resection, however, though often technically feasible, has questionable oncologic impact, is not without risk and is usually reserved for isolated cases. The value of extended lymphadenectomy is frequently debated; the recent level I evidence demonstrates no advantage. Multivisceral resections, i.e. tumors, often in the tail of the pancreas, with invasion of the colon or stomach or other surrounding tissues, while associated with an increased morbidity and a longer hospital stay, do however show comparable mortality-and survival rates to those without such infiltration and therefore should be performed if technically feasible. Routine resection for metastatic disease however does not seem to show any advantage over palliative treatment but may be an option in selected patients with easily removable metastases. In conclusion pancreatic surgery beyond the traditional limits is established in tumors infiltration the venous system and may be a considered approach in selected patients with locally infiltrating pancreatic cancer or metastasis.

Prognostic relevance of number and ratio of metastatic lymph nodes in resected pancreatic, ampullary, and distal bile duct carcinomas

BACKGROUND

Lymph node ratio (LNR) may be more useful than nodal (N) status in prognostic subclassification of adenocarcinomas after pancreatoduodenectomy. Ampullary (AC), biliary (DBC), and pancreatic (PC) adenocarcinomas are biologically distinct, and nodal involvement may have different prognostic importance among these separate cancers.

METHODS

We included 179 consecutive pancreatoduodenectomies for PC, AC, or DBC, and performed standardized histopathologic evaluation, including prospective registration and retrospective reevaluation of the cancer origin. Associations between histopathologic variables and LNR, N status, and number of metastatic nodes were evaluated. Unadjusted and adjusted survival analysis was performed.

RESULTS

Overall 5 year survival was 6% for PC (n=72), 26% for DBC (n=46), and 46% for AC (n=61). Lymph node involvement was more frequent in PC (75%) than in AC (48%) and DBC (57%). In PC, N status did not discriminate between prognostic groups (N1 vs. N0; p=0.31). However, increasing LNR was associated with poorer survival in unadjusted analysis, as well as when adjusting for margin involvement, degree of differentiation, and tumor diameter (p=0.032; hazard ratio 1.87, 95% confidence interval 1.06-3.31). In AC and DBC, N status clearly discriminated between subgroups of patients with different long-term survival in unadjusted and adjusted survival analysis (N1 vs. N0; p<0.001), whereas number of metastatic nodes and LNR did not predict survival among node-positive resections.

CONCLUSIONS

The predictive value of nodal involvement depends on the type of cancer within the pancreatic head. In AC and DBC, N status adequately discriminates between good and poor prognosis. In PC, LNR may be more powerful in prognostic subclassification.

Current opinion on lymphadenectomy in pancreatic cancer surgery

BACKGROUND

Adenocarcinoma of the pancreas exhibits aggressive behavior in growth, inducing an extremely poor prognosis with an overall median 5-year survival rate of only 1%-4%. Curative resection is the only potential therapeutic opportunity.

DATA SOURCES

A PubMed search of relevant articles published up to 2009 was performed to identify information about the value of lymphadenectomy and its extent in curative resection of pancreatic adenocarcinoma.

RESULTS

Despite recent advances in chemotherapy, radiotherapy or even immunotherapy, surgery still remains the major factor that affects the outcome. The initial promising performance in Japan gave conflicting results in Western countries for the extended and more radical pancreatectomy; it has failed to prove beneficial. Four prospective, randomized trials on extended versus standard lymphadenectomy during pancreatic cancer surgery have shown no improvement in long-term survival by the extended resection. The exact lymph node status, including malignant spread and the total number retrieved as well as the lymph node ratio, is the most important prognostic factor. Positive lymph nodes after pancreatectomy are present in 70%. Paraaortic lymph node spread indicates poor prognosis.

CONCLUSIONS

Undoubtedly, a standard lymphadenectomy including >15 lymph nodes must be no longer preferred in patients with the usual head location. The extended lymphadenectomy does not have any place, unless in randomized trials. In cases with body or tail location, the radical antegrade modular pancreatosplenectomy gives promising results. Nevertheless, accurate localization and detailed examination of the resected specimen are required for better staging.

Epidemiology of pancreatic cancer in Norway: trends in incidence, basis of diagnosis and survival 1965-2007

OBJECTIVE

Pancreatic cancer is the second most frequent gastrointestinal cancer in the Western world. Few reports on concomitant trends in pancreatic cancer incidence, diagnosis, mortality and survival exist at the national level. This study provides a baseline overview of the temporal patterns in these four indicators over the past four decades in Norway.

MATERIAL AND METHODS

We analysed trends in incidence, basis of diagnosis, relative survival and mortality from the Cancer Registry of Norway for the period 1965-2007.

RESULTS

Included were 21,663 patients with pancreatic cancers. Incidence and mortality rates remained at around 6-8 per 100,000 over the study period. Diagnoses based on clinical examination alone dropped from 12.5% (in the 1950s) to <1% (in the 2000s), while use of imaging techniques, such as CT and MRI, increased from 3.6% to >30%. Previously high rates of autopsy-verified diagnosis and non-therapeutic surgery decreased accordingly. Consistently more primary tumours (from 12.9% to 19.4%) and metastases (from 12.5% to 22.4%) had histological examination, and use of endoscopy increased to approximately 10%. Relative survival after diagnosis of pancreatic cancer remains very low. However, in recent years, a modest improvement in short-term survival has been noted, with 1-year survival rates of 18% and 16% for males and females, respectively.

CONCLUSIONS

The incidence and mortality for pancreatic cancer remain largely unchanged, with few 5-year survivors. Improved short-term survival may reflect more aggressive use of surgery and chemotherapy. Further elucidation of risk factors in pancreatic cancer is needed to enable effective prevention, early detection and improved treatment strategies.