Clinical Impact of Unexpected Para-Aortic Lymph Node Metastasis in Surgery for Resectable Pancreatic Cancer

Abstract

Radiologically identified para-aortic lymph node (PALN) metastasis is contraindicated for pancreatic cancer (PC) surgery. There is no clinical consensus for unexpected intraoperative PALN enlargement. To analyze the prognostic role of unexpected PALN enlargement in resectable PC, we retrospectively reviewed data of 1953 PC patients in a single tertiary center. Patients with unexpected intraoperative PALN enlargement (group A1, negative pathology, n = 59; group A2, positive pathology, n = 13) showed median overall survival (OS) of 24.6 (95% CI: 15.2–33.2) and 13.0 (95% CI: 4.9–19.7) months, respectively. Patients with radiological PALN metastasis without other metastases (group B, n = 91) showed median OS of 8.6 months (95% CI: 7.4–11.6). Compared with group A1, groups A2 and B had hazard ratios (HRs) of 2.79 (95% CI, 1.4–5.7) and 2.67 (95% CI: 1.8–4.0), respectively. Compared with group A2, group B had HR of 0.96 (95% CI: 0.5–1.9). Multivariable analysis also showed positive PALN as a negative prognostic factor (HR 2.57, 95% CI: 1.2–5.3), whereas positive regional lymph node did not (HR 1.32 95% CI: 0.8–2.3). Thus, unexpected malignant PALN has a negative prognostic impact comparable to radiological PALN metastasis. This results suggests prompt pathologic evaluation for unexpected PALN enlargements is needed and on-site modification of surgical strategy would be considered.

Impact of para aortic lymph node removal on survival following resection for pancreatic adenocarcinoma

“…Our results seem to support findings in previous studies indicating that although PALN + status is a predictor of a shorter OS, this should not lead to deviation from planned tumor resection [6,8] although this is still recommended in a recent study, [17].…”

“…First, multiple studies have demonstrated a survival advantage of adjuvant chemotherapy following surgical treatment of PDAC [18][19][20], and this may have an impact on results in multivariate models. In our study, we have factored this into the multivariable models as opposed to a recent report concluding that PALN + status should result in aborted surgery [17]. Furthermore, although we have not been able to correct for this in the statistics, the choice of chemotherapeutic agents as well as treatment completion is likely also important [19].…”

The Complexity of the Pancreatic Lymphatic System and the Key Role of Para-Aortic Lymph Node Metastasis in Pancreatic Cancer Prognosis Prediction: A Comprehensive Review

“…A detailed examination of this lymph node offers valuable insights into overall lymphatic drainage patterns, aiding clinicians in formulating comprehensive and tailored treatment strategies for patients with various medical conditions, including cancer [24,28]. PALNs are considered "extra-regional" lymph nodes, becoming involved only after metastatic spread has already affected the peri-pancreatic first-echelon lymph nodes [29]. Several reports, although most of them share the bias of retrospective analysis, describe that the prognosis of patients with metastatic PALN is significantly worse if compared with patients with negative metastatic cases [30].…”

“…The PALN assessment involvement is essential in determining the extent of disease spread and plays an important role in cancer staging. The presence of metastasis in these nodes may influence treatment decisions, including considering more aggressive surgical interventions or targeted therapies [29]. Consequently, a thorough understanding of the risk and detection of PALN metastasis in pancreatic cancer is imperative for clinicians to devise effective and personalized treatment strategies that address the complexities of the disease and improve patient outcomes [24,27,30].…”

“…In the absence of these distant metastases, the presence of PALN metastasis becomes a crucial factor in defining the resectability of the disease. Therefore, identifying PALN metastasis presence is a crucial factor in determining the overall surgical approach for patients with pancreatic cancer [24,28,29].…”