Meta-analysis of the efficacies of extended and standard pancreatoduodenectomy for ductal adenocarcinoma of the head of the pancreas

Surgery for pancreatic cancer: current controversies and challenges

Two areas that remain the focus of improvement in pancreatic cancer include high post-operative morbidity and inability to uniformly translate surgical success into long-term survival. This narrative review addresses specific aspects of pancreatic cancer surgery, including neoadjuvant therapy, vascular resections, extended pancreatectomy, extent of lymphadenectomy and current status of minimally invasive surgery. R0 resection confers longer disease-free survival and overall survival. Vascular and adjacent organ resections should be undertaken after neoadjuvant therapy, only if R0 resection can be ensured based on high-quality preoperative imaging, and that too, with acceptable post-operative morbidity. Extended lymphadenectomy does not offer any advantage over standard lymphadenectomy. Although minimally invasive distal pancreatectomies offers some short-term benefits over open distal pancreatectomy, safety remains a concern with minimally invasive pancreatoduodenectomy. Strict adherence to principles and judicious utilization of surgery within a multimodality framework is the way forward.

Pancreatic cancer in 2021: What you need to know to win

Pancreatic cancer is one of the solid tumors with the worst prognosis. Five-year survival rate is less than 10%. Surgical resection is the only potentially curative treatment, but the tumor is often diagnosed at an advanced stage of the disease and surgery could be performed in a very limited number of patients. Moreover, surgery is still associated with high post-operative morbidity, while other therapies still offer very disappointing results. This article reviews every aspect of pancreatic cancer, focusing on the elements that can improve prognosis. It was written with the aim of describing everything you need to know in 2021 in order to face this difficult challenge.

The Current Treatment Paradigm for Pancreatic Ductal Adenocarcinoma and Barriers to Therapeutic Efficacy

Pancreatic ductal adenocarcinoma (PDAC) has a dismal prognosis, with a median survival time of 10-12 months. Clinically, these poor outcomes are attributed to several factors, including late stage at the time of diagnosis impeding resectability, as well as multi-drug resistance. Despite the high prevalence of drug-resistant phenotypes, nearly all patients are offered chemotherapy leading to modest improvements in postoperative survival. However, chemotherapy is all too often associated with toxicity, and many patients elect for palliative care. In cases of inoperable disease, cytotoxic therapies are less efficacious but still carry the same risk of serious adverse effects, and clinical outcomes remain particularly poor. Here we discuss the current state of pancreatic cancer therapy, both surgical and medical, and emerging factors limiting the efficacy of both. Combined, this review highlights an unmet clinical need to improve our understanding of the mechanisms underlying the poor therapeutic responses seen in patients with PDAC, in hopes of increasing drug efficacy, extending patient survival, and improving quality of life.

Extended lymph node resection versus standard resection for pancreatic and periampullary adenocarcinoma

BACKGROUND

Pancreatic and periampullary adenocarcinomas account for some of the most aggressive malignancies, and the leading causes of cancer-related mortalities. Partial pancreaticoduodenectomy (PD) with negative resection margins is the only potentially curative therapy. The high prevalence of lymph node metastases has led to the hypothesis that wider excision with the removal of more lymphatic tissue could result in an improvement of survival, and higher rates of negative resection margins.

OBJECTIVES

To compare overall survival following standard (SLA) versus extended lymph lymphadenectomy (ELA) for pancreatic head and periampullary adenocarcinoma. We also compared secondary outcomes, such as morbidity, mortality, and tumour involvement of the resection margins between the two procedures.

SEARCH METHODS

We searched CENTRAL, MEDLINE, PubMed, and Embase from 1973 to September 2020; we applied no language restrictions.

SELECTION CRITERIA

Randomised controlled trials (RCT) comparing PD with SLA versus PD with ELA, including participants with pancreatic head and periampullary adenocarcinoma.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened references and extracted data from study reports. We calculated pooled risk ratios (RR) for most binary outcomes except for postoperative mortality, for which we estimated a Peto odds ratio (Peto OR), and mean differences (MD) for continuous outcomes. We used a fixed-effect model in the absence of substantial heterogeneity (I² < 25%), and a random-effects model in cases of substantial heterogeneity (I² > 25%). Two review authors independently assessed risk of bias, and we used GRADE to assess the quality of the evidence for important outcomes.

MAIN RESULTS

We included seven studies with 843 participants (421 ELA and 422 SLA). All seven studies included Kaplan-Meier curves for overall survival. There was little or no difference in survival between groups (log hazard ratio (log HR) 0.12, 95% confidence interval (CI) -3.06 to 3.31; P = 0.94; seven studies, 843 participants; very low-quality evidence). There was little or no difference in postoperative mortality between the groups (Peto odds ratio (OR) 1.20, 95% CI 0.51 to 2.80; seven studies, 843 participants; low-quality evidence). Operating time was probably longer for ELA (mean difference (MD) 50.13 minutes, 95% CI 19.19 to 81.06 minutes; five studies, 670 participants; moderate-quality evidence). There was substantial heterogeneity between the studies (I² = 88%; P < 0.00001). There may have been more blood loss during ELA (MD 137.43 mL, 95% CI 11.55 to 263.30 mL; two studies, 463 participants; very low-quality evidence). There was substantial heterogeneity between the studies (I² = 81%, P = 0.02). There may have been more lymph nodes retrieved during ELA (MD 11.09 nodes, 95% CI 7.16 to 15.02; five studies, 670 participants; moderate-quality evidence). There was substantial heterogeneity between the studies (I² = 81%, P < 0.00001). There was little or no difference in the incidence of positive resection margins between groups (RR 0.81, 95% CI 0.58 to 1.13; six studies, 783 participants; very low-quality evidence).

AUTHORS' CONCLUSIONS

There is no evidence of an impact on survival with extended versus standard lymph node resection. However, the operating time may have been longer and blood loss greater in the extended resection group. In conclusion, current evidence neither supports nor refutes the effect of extended lymph lymphadenectomy in people with adenocarcinoma of the head of the pancreas.

Meta-analysis and trial sequential analysis of randomised controlled trials comparing standard versus extended lymphadenectomy in pancreatoduodenectomy for adenocarcinoma of the head of pancreas

PURPOSE

To compare baseline demographics, operative, and survival outcomes of randomised controlled trials (RCTs) comparing standard lymphadenectomy versus extended lymphadenectomy in patients undergoing pancreaticoduodenectomy for pancreatic head cancer METHODS: In compliance with PRISMA standards we performed a meta-analysis of baseline demographics, operative, and survival outcomes of RCTs comparing standard lymphadenectomy versus extended lymphadenectomy in patients undergoing pancreaticoduodenectomy for pancreatic head cancer. The uncertainties associated with varying follow-up periods among the included studies were resolved by analysis of time-to-event outcomes. Moreover, we performed trial sequential analysis (TSA) to determine whether the available evidence is conclusive and to assess the risk of type 1 or type 2 errors.

RESULTS

Overall, 724 patients from 5 RCTs were included. The included populations were comparable in terms of baseline characteristics. There was no difference between standard and extended lymphadenectomy in terms of pancreatic fistula (OR 0.64, P = 0.11), delayed gastric emptying (OR 0.68, P = 0.40), bile leak (OR 0.33, P = 0.06), wound infection (OR 0.53, P = 0.06), abscess (OR 0.83, P = 0.63), total complications (OR 0.73, P = 0.27), postoperative mortality (OR 1.01, P = 0.85), and overall survival (HR 1.10, P = 0.46). TSA suggested that meta-analysis was conclusive with low risk of type 2 error. The results remained consistent through subgroup analyses based on lymph node positive or negative status and studies from the West and East.

CONCLUSIONS

Robust evidence from randomised controlled trials (Level 1) suggests no difference in postoperative and survival outcomes between standard and extended lymphadenectomy in patients undergoing pancreaticoduodenectomy for pancreatic head cancer. The findings were consistent in patients with positive and negative lymph node status and in studies from the West or East.

Impact of examined lymph node count on prognosis in patients with lymph node-negative pancreatic body/tail ductal adenocarcinoma

Background

Because the overall prognosis remains dismal for patients with resected pancreatic cancer (PC), we aimed to explore the prognostic impact of examined lymph node (ELN) count on lymph node (LN)-negative pancreatic body/tail ductal adenocarcinoma.

Methods

Patients' data were extracted from the Surveillance, Epidemiology, and End Results (SEER) database (National Cancer Institute, USA) to investigate the relationship between ELN count and survival outcomes of LN-negative pancreatic body/tail ductal adenocarcinoma.

Results

A total of 700 patients were included, and the median number of ELNs was 11. The respective 1-, 3-, 5-year overall survival (OS) rates were 75.3%, 37.7%, 30.3%, and the 1-, 3-, 5-year cancer-specific survival (CSS) were 78.3%, 41.7%, 34.5%. The X-tile analysis showed that 14 was the most optimal cutoff for both OS and CSS. Kaplan-Meier survival analysis indicated that patients with ELNs >14 had better OS and CSS than ELNs ≤14. Multivariate Cox analysis showed ELNs ≤14 was an independent risk factor for both OS [hazard ratio (HR), 1.357; 95% confidence interval (CI), 1.080-1.704; P=0.009] and CSS (HR, 1.394; 95% CI, 1.092-1.778; P=0.008).

Conclusions

ELN count is associated with the survival rate in patients with LN-negative pancreatic body/tail ductal adenocarcinoma. Accurate nodal staging for these patients requires more than 14 ELNs.

Efficacy of extended versus standard lymphadenectomy in pancreatoduodenectomy for pancreatic head adenocarcinoma. An update meta-analysis

BACKGROUND

Surgical resection is the only possible cure for pancreatic cancer, it remains controversial whether extend lymphadenectomy in pancreatoduodenectomy (EPD) is better than standard lymphadenectomy in pancreatoduodenectomy (SPD). The aim of this study was to compare the efficacy of EPD with SPD for pancreatic head adenocarcinoma.

METHODS

A specific search of online databases including PubMed, Web of Science, Embase, and Cochrane library was conducted from January 1990 to October 2018. Relative perioperative outcomes were synthesized. Single-arm meta-analysis was also performed.

RESULTS

A total of eight studies involving 687 (342 vs 345) patients were included for analysis in our study. The number of lymph nodes harvested [24.54 vs 13.29; weighted mean difference (WMD) -10.69, P = 0.000], operative time (469.84 min vs 354.85 min; WMD -99.09, P = 0.000), and diarrhea (postoperative three months) [45.1% vs 18.2%; odds radio (OR) 0.20, P = 0.014] were significantly higher in patients who underwent EPD than SPD. The perioperative complications (35% vs 28.8%; OR 0.79, P = 0.186), tumor size (3.27 cm vs 3.248 cm; WMD -0.11, P = 0.256), lymph node metastasis (66% vs 55.9%; OR 0.71, P = 0.105), and positive margin (10.4% vs 11.3%; OR 1.28, P = 0.392) were no significant differences between EPD group and SPD group. Extended lymphadenectomy in pancreatoduodenectomy dose not contribute to the overall survival of patients with adenocarcinoma of the pancreatic head [hazard ratio (HR) 0.95; 95% CI 0.78-1.15; P = 0.61].

CONCLUSION

The update meta-analysis shows that EPD failed to improve the overall survival, may even lead to increased morbidity.

Survival, morbidity and mortality of pancreatic adenocarcinoma after pancreaticoduodenectomy with a total mesopancreas excision

INTRODUCTION

pancreatic adenocarcinoma is the most common malignancy in the periampullary region, with a five-year survival rate around 20%.

OBJECTIVE

the goal of our study was to determine the survival and safety data of a number of patients that underwent a cephalic duodenopancreatectomy (CDP) with total mesopancreas excision (TMPE).

MATERIAL AND METHODS

a prospective observational study was performed of 114 patients with pancreatic adenocarcinoma who underwent duodenopancreatectomy and TMPE over the period 2008-2017. Demographic variables, tumor stage, number of lymph nodes excised, lymph node ratio, R classification, the prognostic factor disease-free interval and survival were all assessed in a multivariate analysis.

RESULTS

complications were reported for 54 (47.3%) patients, of which 22 (19.3%) were categorized as serious. The mortality rate was 4.3% and the mean follow-up was 26.2 months. During this period, 73 (64%) patients relapsed after a mean interval of 40.9 months. The relapse pattern was mainly hepatic (26.3%), followed by local relapse (20%). Mean survival was 40.38 and actuarial survival was 26.6% at five years. Relapse-related factors included stage T3 or higher (RR 8.1 [1.1-61]) and an R1 resection (RR 13.4 [2.7-66.5]) and survival-related factors included an R1 resection (RR 10.7 [2.5-46.2]).

CONCLUSION

TMPE ensures an adequate lymphadenectomy and lymph node ratio according to reported standards. The survival of patients that have undergone surgery for pancreatic adenocarcinoma in our institution is 68.4% at one year and 26.6% at five years. An R1 resection is the primary factor for both relapse and survival.

Distal Pancreatectomy Combined with Multivisceral Resection Is Associated with Postoperative Complication Rates and Survival Comparable to Those After Standard Procedures

BACKGROUND

For pancreatic tumors located in the body or tail of the pancreas, distal pancreatectomy (DP) remains the surgical procedure of choice to achieve radical tumor removal. Purpose of this study was to evaluate outcome and overall survival of patients who underwent DP combined with multivisceral resection (MVR).

METHODS

Retrospective single-center case-matched analysis. Between January 1994 and June 2014, 494 consecutive patients were entered into a prospective database, and 126 patients undergoing DP + MVR (cases) were matched with 126 patients undergoing DP (controls) for gender, age, and underlying final diagnosis.

RESULTS

There were no significant differences in patient demographics. Rates of postoperative pancreatic fistula (POPF) (36 (28.6%) vs. 29 (23.0%); p = 0.388) and postpancreatectomy hemorrhage (PPH) (7 (5.5%) vs. 5 (3.9%); p = 0.769) did not reveal any significant differences. Although operative time (237.8 ± 57.9 vs. 203.5 ± 34.5; p < 0.001) and the necessity for intraoperative transfusions (18 (14.3%) vs. 5 (4.0%); p < 0.001) was significantly higher, the number of patients with major complications (the Clavien-Dindo ≥ 3) was not increased (27 (19.8%) vs. 20 (15.9%); p = 0.332) in the DP + MVR group. Midterm survival analysis indicated no significant difference for adenocarcinoma and neuroendocrine tumors for either group.

CONCLUSION

DP + MVR is a feasible and safe surgical procedure to achieve radical tumor removal and can offer beneficial survival outcomes. Although operative time and intraoperative transfusions are enhanced, POPF, PPH, or major complications (the Clavien-Dindo ≥ 3) are not significantly increased after DP + MVR. DP + MVR can therefore be recommended in selected patients for resection of extended tumors within the concept of interdisciplinary strategies.

Prognostic role of nodal ratio, LODDS, pN in patients with pancreatic cancer with venous involvement

Background

The UICC/AJCC TNM staging system classifies lymph nodes as N0 and N1 in pancreatic cancer. Aim of the study is to determine whether the number of examine nodes, the nodal ratio (NR) and the logarithm odds of positive lymph nodes (LODDS) may better stratify the prognosis of patients undergoing pancreatectomy combined with venous resection for pancreatic cancer with venous involvement.

Methods

A multicenter database of 303 patients undergoing pancreatectomy in 9 Italian referral centers was analyzed. The prognostic impact of number of retrieved and examined nodes, NR, LODDS was analyzed and compared with ROC curves analysis, Pearson test, univariate and multivariate analysis.

Results

The number of metastatic nodes, pN, the NR and LODDS was significantly correlated with survival at multivariate analyses. The corresponding AUC for the number of metastatic nodes, pN, the NR and LODDS were 0.66, 0.69, 0.63 and 0.65, respectively. The Pearson test showed a significant correlation between the number of retrieved lymph nodes and number of metastatic nodes, pN and the NR. LODDS had the lower coefficient correlation. Concerning N1 patients, the NR, the LODDS and the number of metastatic nodes were able to significantly further stratify survival (p = 0.040; p = 0.046; p = 0.038, respectively).

Conclusions

The number of examined lymph nodes, the NR and LODDS are useful for further prognostic stratification of N1 patients in the setting of pancreatectomy combined with PV/SMV resection. No superiority of one over the others methods was detected.

Extent of lymphadenectomy to associate with pancreaticoduodenectomy in patients with pancreatic head cancer for better tumor staging

OBJECTIVES

To define the extent of lymphadenectomy to associate with surgery for pancreatic head cancer.

BACKGROUND

Pancreaticoduodenectomy with extended lymphadenectomy fails to prolong patient survival.

METHODS

Prospective randomized and nonrandomized controlled trials (RCTs and NRCTs), meta-analyses, retrospective reviews, consensus conferences and pre- and intraoperative diagnoses of lymph node (LN) metastases were retrieved. Standard and extended lymphadenectomies were reviewed, including their effects on postoperative complications, mortality rate and long-term survival. The minimum total number of LN examined (TNLE) for adequate tumor staging, and the incidence of metastasis to each LN station were also considered. A pros and cons analysis was performed on the removal of each LN station.

RESULTS

Eleven retrospective studies (2514 patients), five prospective NRCTs (545 patients), and five prospective RCTs (586 patients) described different lymphadenectomies, which obtained similar long-term results. Five meta-analyses showed they did not influence long-term survival. However, N status is an important component of tumor staging. The recommended minimum TNLE is 15. The percent incidence of metastasis to each LN station was calculated considering at least 385 and up to 3725 patients. Preoperative imaging and intraoperative exploration frequently fail to identify metastatic nodes. A pros and cons analysis suggests that lymph node status is better established removing the following LN stations: 6, 8a-p, 12a-b-c, 13a-b, 14a-b-c-d, 16b1, 17a-b. Metastasis to 16b1 LNs significantly worsens prognosis. Their removal and frozen section examination, before proceeding with resection, may contraindicate resection.

CONCLUSION

A standard lymphadenectomy demands an adequate TNLE and removal of the LN stations metastasizing more frequently, without increasing the surgical risk.