Diagnostic performance of CT-based node reporting and data system (Node-RADS) for regional lymph node metastasis in periampullary cancer.

PURPOSE: This study aims to evaluate the diagnostic performance of the Node Reporting and Data System (Node-RADS) for assessing regional lymph node metastasis in patients with periampullary cancer, using histopathology as the reference standard.

METHODS

We conducted a retrospective analysis of 50 patients who received contrast-enhanced CT and subsequent surgical resection between January 2010 and July 2024. Patient demographics, clinical characteristics, and histopathologic data were collected. The diagnostic efficacy of Node-RADS, including lymph node size and configuration ('border', 'texture' and 'shape') of lymph nodes. Receiver operating characteristic (ROC) curve analysis was conducted to calculate the AUC for each parameter.

RESULTS

The patient cohort had a mean age of 61.5 years, with a predominance of males (64.0%). Among these patients, 19 (38.0%) exhibited lymph node metastasis (pN+). Node-RADS scores ≥ 3 demonstrated strong diagnostic efficacy in assessing lymph node metastasis in periampullary cancer (sensitivity: 89.5%, specificity: 71.0%, AUC: 80.2%). Compared to the conventional short-axis criterion (≥ 10 mm), Node-RADS showed significantly superior diagnostic efficiency (p < 0.001). The optimal cut-off for short-axis diameter was identified as 8 mm, yielding an AUC of 76.6%. Inter-reader agreement for assessing regional lymph node metastasis in periampullary cancer using Node-RADS was substantial (κ = 0.775), indicating reliable reproducibility among radiologists.

CONCLUSIONS

The Node-RADS significantly enhances the diagnostic performance for lymph node staging in periampullary cancer. The structured and reproducible approach can provide treatment guidance and predict disease prognosis for patients with periampullary cancer.