Should a standard lymphadenectomy include the No. 9 lymph nodes for body and tail pancreatic ductal adenocarcinoma?

Extended lymphadenectomy based on the TRIANGLE for pancreatic head cancer: a single-center experience

BACKGROUND

This study was to compare the safety and efficacy of different lymphadenectomy methods in patients with pancreatic head cancer undergoing pancreaticoduodenectomy (PD).

MATERIAL AND METHODS

A total of 150 patients were included in this study. Patients were divided into Group A (n = 79), Group B (n = 44), and Group C (n = 27) according to the different lymphadenectomy methods. The clinical endpoint was time to progression (TTP) and overall survival (OS). Postoperative complications of different lymphadenectomy methods were compared respectively. TTP and OS of the three groups were compared by Kaplan-Meier curves.

RESULTS

There were no significant differences between the three groups in operative time (P = 0.300), death in the hospital (P = 0.253), postoperative hemorrhage (P = 0.863), postoperative pancreatic fistula (POPF) B/C (P = 0.306), bile leakage (P = 0.215), intestinal fistula (P = 0.177), lymphatic leakage (P = 0.267), delayed gastric emptying [(DGE) (P = 0.283)], ICU stay (P = 0.506), and postoperative hospital stay [(PHS) (P = 0.810)]. Median TTP in Groups B and C was significantly longer than in Group A (log-rank test, A vs B: P = 0.0005, A vs C: P = 0.0001). Median OS between the three groups has no statistical difference (P = 0.1546).

CONCLUSIONS

Extended lymphadenectomy methods based on the TRIANGLE do not increase perioperative complications significantly and can effectively delay tumor progression in patients with pancreatic head cancer.

The Role of Non-Peripancreatic Lymph Nodes in the Survival of Patients Suffering from Pancreatic Cancer of the Body and Tail: A Systematic Review and Meta-Analysis of High-Quality Studies

Lymph nodes (LNs)' metastases have a well-known detrimental impact on the survival outcomes of patients suffering from pancreatic cancer of the body and tail. However, the extent of the lymphadenectomy for this tumor location is still debated. The aim of this study was to systematically review the current literature to explore the incidence and the prognostic impact of non-peripancreatic lymph nodes (PLNs) in patients suffering from pancreatic cancer of the body and tail. A systematic review was conducted according to PRISMA and MOOSE guidelines. The primary endpoint was to assess the impact of non-PLNs on overall survival (OS). As a secondary endpoint, the pooled frequencies of different non-PLN stations' metastatic patterns according to tumor location were explored. Eight studies were included in data synthesis. An increased risk of death for patients with positive non-PLNs was detected (HR: 2.97; 95% CI: 1.81-4.91; p < 0.0001). Meta-analysis of proportions pointed out a 7.1% pooled proportion of nodal infiltration in stations 8-9. The pooled frequency for station 12 metastasis was 4.8%. LN stations 14-15 were involved in 11.4% of cases, whereas station 16 represented a site of metastasis in 11.5% of cases. Despite its potential beneficial effect on survival outcome, a systematic extended lymphadenectomy could not be recommended yet for patients suffering from PDAC of the body/tail.

Optimal lymph-node dissection for pancreatic tail cancer

PURPOSE

The optimal range of lymph-node dissection for pancreatic tail cancer remains unclear. We investigated the location and frequency of lymph-node metastases to identify the correct range of lymph-node dissection for pancreatic tail cancer.

METHODS

We analyzed clinical data retrospectively, on patients who underwent distal pancreatectomy for resectable left-sided pancreatic cancer, between February, 2006 and March, 2021. Eligible patients were divided into two groups according to the tumor location: those with pancreatic tail cancer (Pt group) and those with pancreatic body or body and tail cancer (non-Pt group).

RESULTS

Of the 96 patients analyzed, 61 (64%) were assigned to the Pt group and 35 (36%) were assigned to the non-Pt group. Metastases to stations 7, 8, 9, 10, 11, 14, and 18 were found in 0 (0%), 0 (0%), 0 (0%), 4 (7%), 18 (30%), 2 (4%), and 10 (17%) patients in the Pt group, and in 1 (3%), 4 (12%), 2 (6%), 1 (3%), 18 (51%), 3 (9%), and 6 (17%) patients in the non-Pt group, respectively.

CONCLUSION

Lymph-node dissection at stations 7, 8, and 9 might not be necessary in patients with resectable pancreatic cancer confined to the pancreatic tail.

Optimal Region of Lymph Node Dissection in Distal Pancreatectomy for Left-Sided Pancreatic Cancer Based on Tumor Location

BACKGROUND

The optimal lymph node (LN) dissection for left-sided pancreatic cancer based on tumor location has remained unknown. In particular, the efficacy of LN dissection around the common hepatic artery and the celiac axis for distal tumors has not been established. This study was designed to elucidate the frequency and prognostic impact of LN metastasis, focusing on tumor location.

METHODS

Data from 110 patients with invasive pancreatic cancer who underwent distal pancreatectomy between 2007 and 2020 were collected. We used a quantitative value-the distance between the left side of the portal vein and the right side of tumor (DPT)-to define the tumor location. LN stations were divided into two groups: peripancreatic lymph nodes (PLN) and non-PLN. We then analyzed the frequency of LN metastasis based on the tumor location and prognostic factors.

RESULTS

Non-PLN metastasis was observed in 7.3% of patients. Non-PLN metastasis was found only in patients with a DPT < 20 mm. Patients with non-PLN metastasis exhibited a significantly worse prognosis than those with only-PLN metastasis (median survival time: 20.3 vs. 42.5 months, p = 0.048). Multivariate analysis for survival indicated that tumor size > 4 cm (hazard ratio [HR]: 2.23, p = 0.012) and metastasis in the non-PLN region (HR: 3.02, p = 0.015), and inability to undergo adjuvant chemotherapy (HR: 2.81, p = 0.0018) were also associated with poor prognosis.

CONCLUSIONS

Dissection of the non-PLN region can be avoided in selected patients with DPT ≥ 20 mm.

Role of lymphadenectomy in resectable pancreatic cancer

BACKGROUND

Pancreatic cancer (PC) remains one of the most devastating malignant diseases, predicted to become the second leading cause of cancer-related death by 2030. Despite advances in surgical techniques and in systemic therapy, the 5-year relative survival remains a grim 9% for all stages combined. The extent of lymphadenectomy has been discussed intensively for decades, given that even in early stages of PC, lymph node (LN) metastasis can be detected in approximately 80%.

PURPOSE

The primary objective of this review was to provide an overview of the current literature evaluating the role of lymphadenectomy in resected PC. For this, we evaluated randomized controlled studies (RCTs) assessing the impact of extent of lymphadenectomy on OS and studies evaluating the prognostic impact of anatomical site of LN metastasis and the impact of the number of resected LNs on OS.

CONCLUSIONS

Lymphadenectomy plays an essential part in the multimodal treatment algorithm of PC and is an additional therapeutic tool to increase the chance for surgical radicality and to ensure correct staging for optimal oncological therapy. Based on the literature from the last decades, standard lymphadenectomy with resection of at least ≥ 15 LNs is associated with an acceptable postoperative complication risk and should be recommended to obtain local radicality and accurate staging of the disease. Although radical surgery including appropriate lymphadenectomy of regional LNs remains the only chance for long-term tumor control, future studies specifically assessing the impact of neoadjuvant therapy on extraregional LNs are warranted.

Reappraisal of nodal staging and study of lymph node station involvement in distal pancreatectomy for body-tail pancreatic ductal adenocarcinoma

BACKGROUND

The pattern of nodal spread in body-tail pancreatic ductal adenocarcinoma (PDAC) has been poorly investigated. This study analyzed the characteristics of lymph node (LN) involvement and the prognostic role of nodal metastases stratified by LN stations.

METHODS

All upfront distal pancreatectomies (DPs) for PDAC (2000-2017) with complete information on station 8,10,11, and 18 were included. Clinico-pathological correlates and survival were investigated using uni- and multivariable analyses.

RESULTS

Among 100 included patients, 28 were N0, 42 N1 and 30 N2. The median number of examined LN was 32 (IQR 26-44). Tumor size at preoperative imaging increased across N-classes. Preoperative size >27.5 mm was associated with N2 status. The frequency of nodal metastases at stations 8, 9, 10, 11, and 18 was 12.0%, 10.9%, 3.0%, 71.0%, and 19%, respectively. The pattern of LN spread was independent from primary tumor location (with tail tumors metastasizing to station 8/9 and body tumors to station 10), while it was highly associated with N-class. At multivariable analysis, tumor grading, adjuvant treatment, station 9 and 10 metastases were independent prognostic factors in node-positive patients.

CONCLUSIONS

In patients undergoing upfront DP for PDAC preoperative tumor size is associated with the degree of nodal spread. While station 11 was the most frequently involved, only station-9 and 10 metastases were independent prognostic factors. The site of nodal metastases was somewhat unpredictable based on tumor location. This data has potential implications for allocating patients to neoadjuvant treatment and supports the performance of routine splenectomy during DP for PDAC.

Early recurrence detected by 18F-FDG PET/CT in patients with resected pancreatic ductal adenocarcinoma

F-fluoro-2-deoxy-D-glucose positron emission tomography integrated with computed tomography (F-FDG PET/CT) has been proved to be practical in detecting occult malignant lesions. However, the evidence of its utility in detecting early recurrence after resection of pancreatic ductal adenocarcinoma (PDAC) is lacking. Therefore, the primary aim of the present study is to evaluate the diagnostic value of F-FDG PET/CT in the early postoperative period after radical resection of PDAC.This retrospective study included 32 patients who had F-FDG PET/CT scan within 6 months after radical resection of PDAC between January 2010 and December 2018.In total, 10 positive PET results were found at surgical margins of remnant pancreas, 12 at locoregional lymph nodes, 5 at distant areas, with the corresponding mean maximum standard uptake value (SUVmax) of 5.8 ± 1.1, 5.9 ± 0.9, and 6.4 ± 0.7, respectively. The median follow-up time was 23.5 months (range: 8-75 months), and the median survival time was 39.5 months (95% confidence interval: 14.6-64.4 months) for the entire cohort. Patients with positive PET findings at either locoregional lymph nodes or distant areas obtained significantly poorer overall survival (OS) than those without increased FDG uptake at the corresponding areas (P = .003 and P < .001, respectively). Whereas comparisons of OS between patients with or without increased FDG uptake at the surgical margin of remnant pancreas presented no statistically difference (P = .742).The early application of F-FDG PET/CT after radical resection of PDAC could stratify the prognosis of patients well by detecting occult early recurrence at locoregional lymph nodes and distant areas efficiently.

Immune heterogeneity of head and tail pancreatic lymph nodes in non-obese diabetic mice

The pancreatic lymph node is critical to the pathogenesis of autoimmune diabetes, as it constitutes the initial site for the priming of autoreactive T cells. In this study, we compared the histopathology of the head pancreatic lymph node (HPLN) to the tail pancreatic lymph node (TPLN) in NOD mice. HPLNs and TPLNs were harvested from 4 week-, 8 week-, and 12 week-old NOD mice, and their microvasculature, extracellular matrix, and immune cell subsets were characterized. The percentages of B cells and antigen-presenting cells (APCs) were much higher in the HPLN, as compared to the TPLN. Notably, the HPLNs of 12 week-old mice were characterized by greater expansion of high endothelial venules (HEVs) and lymphatic vessels in comparison to the TPLNs. Finally, we observed a higher density of extracellular matrix (ECM) fibers surrounding the lymphatic vasculature in the HPLNs than in the TPLNs. These data for the first time demonstrate that the HPLN possesses a different immune microanatomy and organization from the TPLN. These novel observations unveil a major phenotypic difference between two types of LNs from the same organ and may highlight an independent fundamental role played by each PLN during the establishment of T1D.