Importance of Nodal Metastases Location in Pancreatoduodenectomy for Pancreatic Ductal Adenocarcinoma: Results from a Prospective, Lymphadenectomy Protocol

Neoadjuvant SBRT plus Elective Nodal Irradiation with Concurrent Capecitabine for Patients with Resectable Pancreatic Cancer: Survival Analysis of a Prospective Phase 1 Trial

BACKGROUND AND PURPOSE

Elective nodal irradiation (ENI) in resectable pancreatic cancer remains undefined, though occult nodal disease is common. This study investigated the use of neoadjuvant stereotactic body radiation therapy (SBRT) to primary disease with ENI, with concurrent capecitabine. Safety data for this protocol were previously reported. In this report, we provide an updated survival analysis.

MATERIALS AND METHODS

This is a prospective, single institution, phase IA/B dose-escalation trial that enrolled patients with biopsy-proven, resectable, pancreatic adenocarcinoma between 2014 - 2019 (NCT1918644). Patients were enrolled into one of the 3 cohorts with escalating dose levels. Neoadjuvant SBRT to the primary tumor was delivered in 5 fractions of 5, 6, or 7 Gy with concomitant capecitabine (1650 mg/m2). All patients received ENI 5 Gy x 5 fractions. Our initial report found no dose-limiting toxicities. Clinicopathologic features were summarized using descriptive statistics. Kaplan-Meier (KM) curves were employed for survival analysis.

RESULTS

Of 17 enrolled patients, 16 were evaluable (94.1%). Thirteen (76.5%) proceeded to surgery. Median follow up was 28.0 months (1.7 - 71.9). Four patients (25.0%) received neoadjuvant chemotherapy and six (37.5%) received adjuvant chemotherapy. Pathologic nodal involvement (69.2%) was associated with a higher risk of any relapse (p<0.01) and distant metastasis (p=0.02). Local failure occurred in 4 (25%) patients with 2/4 of those failures occurring partially within the 25 Gy elective nodal field and 1/4 occurred in the 25 Gy elective nodal field and partially within the 35 Gy tumor field. The median overall survival (OS) and disease-free survival (DFS) were 31.1 months (range, 2.3 - 73.6) and 12.0 months (range, 0.4 - 71.9), respectively. Three-year OS and DFS were 50% and 31.3% overall, and 61.5% and 38.5% for the surgical cohort. Patients with pN+ had worse median OS (23.9 vs 69.3 months; p=0.002) and DFS (9.9 vs 58.9 months; p=0.002). No further radiation related toxicities were noted since the prior report.

CONCLUSION

Neoadjuvant SBRT to the primary tumor with ENI and radiosensitizing chemotherapy is a feasible approach that may improve outcomes in patients with resectable and borderline pancreatic cancer, despite high rates of pathological nodal involvement. Further investigation of this strategy is warranted in a larger cohort.

Prognostic relevance of lymph node metastasis in pancreaticoduodenectomy for distal cholangiocarcinoma: Rational extent and number-based nodal classification for regional lymphadenectomy

BACKGROUND

We investigated the rational extent of regional lymphadenectomy and evaluated the prognostic impact of number-based regional nodal classification in patients with distal cholangiocarcinoma.

METHODS

This study included 191 patients with distal cholangiocarcinoma who underwent pancreaticoduodenectomy. The nos. 8, 12a-b-c-p, 13, 14, and 17 nodes were dissected routinely. The impact of the extent of lymphadenectomy on prognostic stratification performed using number-based nodal classification was evaluated.

RESULTS

The incidence of metastasis in the routinely dissected nodes was 1.0-25.7%, with 5-year overall survival of 0-36.4% in patients with metastasis. The incidence of metastasis in the no. 12p nodes, which were not included in regional nodes in the American Joint Committee on Cancer or International Union Against Cancer staging systems, was 5.8% with a 5-year overall survival of 36.4% in patients with metastasis. When our dissected nodes were adopted (P < .001), number-based nodal classification predicted overall survival better than when regional nodes defined by the International Union Against Cancer or American Joint Committee on Cancer staging systems were used (nos. 8, 12a-b, 13, 14, and 17 nodes with or without no. 9 nodes; P = .004 each). The 5-year overall survival in patients with pN0, pN1 (1-3 positive nodes), and pN2 (≥4 positive nodes) disease was 57.4%, 37.3%, and 13.6%, respectively (P < .001). The pN classification was an independent prognostic factor (pN1, P = .009; pN2, P < .001).

CONCLUSION

The nos. 8, 12a-b-c-p, 13, 14, and 17 nodes should be prioritized as the rational extent of regional lymphadenectomy for distal cholangiocarcinoma for accurate staging. Number-based regional nodal classification is suitable for prognostic stratification.

Laparoscopic and Open Distal Pancreatectomy-An Initial Single-Institution Experience with a Propensity Score Matching Analysis

Laparoscopic distal pancreatectomy is a minimally invasive approach for the surgical treatment of neoplasms in the distal pancreas. This study aimed to compare this approach to the open procedure. A retrospective analysis of a prospectively maintained database of 400 pancreatectomies was performed. The laparoscopic distal pancreatectomy group (LDP) was compared to the open distal pancreatectomy group (ODP). A propensity score matching analysis (PSM) was performed. From 2016 to 2023, 108 distal pancreatectomies were carried out, 19 (17.6%) laparoscopically and 89 (82.4%) openly. The conversion rate was 13.6%. The severe morbidity rates were 28.1% in the ODP group, 47.4% in the LDP group, and 15.8% in the ODP-PSM group. The difference between the latter two was statistically significant (p = 0.034) due to the high rate of Clavien-Dindo grade 3a complications (42.1% versus 10.5%, p = 0.042) in the LDP group. The 90-day mortality rates were 3.3% in the ODP group and 5.3% in the other two groups. The LDP group had a shorter duration of intravenous narcotic analgesia (5 versus 7 days, p = 0.041). There was no difference in the R0 resection or postoperative pancreatic fistula rates. Our attention should be drawn to preventing postoperative complications because the oncological outcomes are already comparable with those of the open procedure, and postoperative pain management is promising.

What is the optimal surgical approach for ductal adenocarcinoma of the pancreatic neck? - a retrospective cohort study

BACKGROUND

The appropriate surgical approach for pancreatic ductal adenocarcinoma (PDAC) is determined by the tumor's relation to the porto-mesenteric axis. Although the extent and location of lymphadenectomy is dependent on the type of resection, a pancreatoduodenectomy (PD), distal pancreatectomy (DP), or total pancreatectomy (TP) are considered equivalent oncologic operations for pancreatic neck tumors. Therefore, we aimed to assess differences in histopathological and oncological outcomes for surgical approaches in the treatment of pancreatic neck tumors.

METHODS

Patients with resected PDAC located in the pancreatic neck were identified from the National Cancer Database (2004-2020). Patients with metastatic disease were excluded. Furthermore, patients with 90-day mortality and R2-resections were excluded from the multivariable Cox-regression analysis.

RESULTS

Among 846 patients, 58% underwent PD, 25% DP, and 17% TP with similar R0-resection rates (p = 0.722). Significant differences were observed in nodal positivity (PD:44%, DP:34%, TP:57%, p < 0.001) and mean-number of examined lymph nodes (PD:17.2 ± 10.4, DP:14.7 ± 10.5, TP:21.2 ± 11.0, p < 0.001). Furthermore, inadequate lymphadenectomy (< 12 nodes) was observed in 30%, 44%, and 19% of patients undergoing PD, DP, and TP, respectively (p < 0.001). Multivariable analysis yielded similar overall survival after DP (HR:0.83, 95%CI:0.63-1.11), while TP was associated with worse survival (HR:1.43, 95%CI:1.08-1.89) compared to PD.

CONCLUSION

While R0-rates are similar amongst all approaches, DP is associated with inadequate lymphadenectomy which may result in understaging disease. However, this had no negative influence on survival. In the premise that an oncological resection of the pancreatic neck tumor is feasible with a partial pancreatectomy, no benefit is observed by performing a TP.

Extent of regional lymphadenectomy and number-based nodal classification for non-ampullary duodenal adenocarcinoma

BACKGROUND

This study aimed to evaluate the adequate extent of regional lymphadenectomy according to tumor location and the impact of number-based nodal classification on survival in patients with non-ampullary duodenal adenocarcinoma (NADAC).

METHODS

A total of 85 patients with NADAC who underwent surgery were enrolled. The frequency of metastasis was calculated for each node group in the respective tumor locations for 63 patients who underwent lymphadenectomy for pT2-pT4 tumor.

RESULTS

The frequency of metastasis in the pancreaticoduodenal (nos. 13 and 17) and superior mesenteric artery (no. 14) nodes was high (16.7 %-52.3 %) regardless of tumor location. Metastasis in the perigastric (nos. 3 and 4d) and right celiac artery (no. 9) nodes was not uncommon (14.3 %-22.2 %) for tumors in the first portion. The frequency of metastasis in the pyloric (nos. 5 and 6) and the other peripancreaticoduodenal (nos. 8 and 12) nodes varied depending on tumor location but could not be ignored for staging. When these nodes were classified as regional nodes, the 5-year survival in patients with pN0, pN1 (1-2 positive nodes), and pN2 (≥3 positive nodes) were 82.9 %, 51.7 %, and 19.2 %, respectively (p < 0.001). pN classification independently predicted survival (pN1, p = 0.022; pN2, p < 0.001).

CONCLUSIONS

Nos. 5, 6, 8, 12, 13, 14, and 17 nodes in all advanced NADAC and nos. 3, 4d, and 9 nodes in advanced NADAC in the first portion should be considered as regional nodes for accurate staging. The number-based nodal classification allows good patients' prognostic stratification.

The Site of Lymph Node Metastasis: A Significant Prognostic Factor in Pancreatic Ductal Adenocarcinoma

OBJECTIVE

While the presence and number of metastatic lymph nodes (LNs) are important prognostic factors for pancreatic ductal adenocarcinoma (PDAC), there is no recommendation to specify metastatic regional LN localization in the current staging system. The aim of this study was to evaluate the prognostic effect of regional metastatic LN localizations in PDAC.

MATERIAL AND METHOD

Metastatic sites of 101 consecutive PDAC patients who underwent pancreaticoduodenectomy were classified as peripancreatic, perigastric, hepatica communis, hepatoduodenal, and superior mesenteric artery. The frequency of metastasis in each region and the association between the presence of metastasis in each site and overall and disease-free survival were statistically analyzed.

RESULTS

Eighty cases (79.2%) had peripancreatic, 7 (6.9%) had perigastric, 6 (5.9%) had hepatica communis, 7 (6.9%) had hepatoduodenal, and 4 (4%) had superior mesenteric artery LN metastasis. The overall and disease-free survival values were significantly shorter in patients with hepatoduodenal LN metastasis (log rank; p= 0.001, p=0.017, respectively). The presence of metastatic superior mesenteric artery LN was significantly associated with shorter disease-free survival in univariate analysis (p=0.017). Hepatoduodenal LN metastasis was an independent predictor of mortality (p=0.005) in multivariate analysis.

CONCLUSION

The presence of hepatoduodenal LN metastasis is an independent poor prognostic factor for mortality. The presence of metastatic LN in the superior mesenteric artery region was significantly associated with shorter disease-free survival time, although not an independent predictor. We conclude that the metastatic regional LN sites, especially the hepatoduodenal region, have an impact on the prognosis, and should be included in synoptic pathology reports.