Lymph node size and its association with nodal metastasis in ductal adenocarcinoma of the pancreas

Abstract

Background: Although lymph node metastasis is a poor prognostic factor in patients with pancreatic ductal adenocarcinoma (PDAC), our understanding of lymph node size in association with PDAC is limited. Increased nodal size in preoperative imaging has been used to detect node metastasis. We evaluated whether lymph node size can be used as a surrogate preoperative marker of lymph node metastasis. Methods: We assessed nodal size and compared it to the nodal metastatic status of 200 patients with surgically resected PDAC. The size of all lymph nodes and metastatic nodal foci were measured along the long and short axis, and the relationships between nodal size and metastatic status were compared at six cutoff points. Results: A total of 4,525 lymph nodes were examined, 9.1% of which were metastatic. The mean size of the metastatic nodes (long axis, 6.9 ± 5.0 mm; short axis, 4.3 ± 3.1 mm) was significantly larger than that of the non-metastatic nodes (long axis, 5.0 ± 4.0 mm; short axis, 3.0 ± 2.0 mm; all p < .001). Using a 10 mm cutoff, the sensitivity, specificity, positive predictive value, overall accuracy, and area under curve was 24.8%, 88.0%, 17.1%, 82.3%, and 0.60 for the long axis and 7.0%, 99.0%, 40.3%, 90.6%, and 0.61 for the short axis, respectively. Conclusions: The metastatic nodes are larger than the non-metastatic nodes in PDAC patients. However, the difference in nodal size was too small to be identified with preoperative imaging. The performance of preoperative radiologic imaging to predict lymph nodal metastasis was not good. Therefore, nodal size cannot be used a surrogate preoperative marker of lymph node metastasis.

Role of CA 19.9 in the Management of Resectable Pancreatic Cancer: State of the Art and Future Perspectives

“…Unfortunately, tools routinely used for the radiological staging of PDAC (e.g., CT scan, MRI, etc.) are impaired by a not negligible rate of down-staged tumors; notably, a lack of sensitivity in nodal involvement assessment is usually reported [ 24 ].…”

CA19.9 Serum Level Predicts Lymph-Nodes Status in Resectable Pancreatic Ductal Adenocarcinoma: A Retrospective Single-Center Analysis

“…Unfortunately, it has been widely reported that even if nodal positivity is one of the main factors influencing the prognosis of PDAC patients, there are limited possibilities for identifying positive lymphnodes with common radiological investigations. These tools offer information regarding the size and the morphology of the lymphnodes, but, as reported by Shin, the accuracy of preoperative radiologic imaging to assess N+ is poor (36).…”

Regional lymph node metastasis detected on preoperative CT and/or FDG-PET may predict early recurrence of pancreatic adenocarcinoma after curative resection

“…In this study, regional LN metastasis detected on preoperative imaging was a significant risk factor for early tumor recurrence, which is consistent with previous reports 13 , 15 . However, the preoperative identification of regional LN metastasis on imaging studies remains challenging due to the lack of consensus on the diagnostic criteria and overall low sensitivity 20 , 21 , 23 , 26 . Our results showed that both the LN OR and LN AND definitions provided sensitivity, specificity, PPV, NPV, and accuracy which fell within the range of previous reports 2 , 27 – 30 .…”