Survival Benefit of Lymph Node Dissection and Prediction of Lymph Node Metastasis in Patients with Intrahepatic Cholangiocarcinoma

Background Lymph node metastasis (LNM) is strongly associated with poor survival in patients with intrahepatic cholangiocarcinoma (ICC); however, the indications for lymph node dissection (LND) are controversial. This study aimed to evaluate the relationship between LNM and patient outcomes and assess the accuracy of preoperative imaging to detect LNM. Methods Eighty-nine patients who underwent curative resection for ICC between 2001 and 2022 were enrolled and retrospectively analyzed. Lymph node status was evaluated before surgery using contrast-enhanced computed tomography (CT) and positron emission tomography/CT. Patients were grouped according to LND status (LND, no LND). LND group patients were further grouped according to LNM status (pN+, LNM-positive; and pN0, LNM-negative). LNM status was determined using pathological examination of surgical lymph node specimens. Results Adequate LND was performed in 44 patients (49.4%). Among these, LNM was diagnosed in 17 (38.6%;). The 3-year rates of OS in the LND/pN + patients, LND/pN0 patients, and no LND patients were 16.2%, 70.0%, and 70.7%, respectively. The corresponding 3-year RFS rates were 11.8%, 52.6%, and 42.6%, respectively. Lymph node diameter > 8 mm on preoperative CT was an independent predictor of LNM. Maximum standardized uptake value on positron emission tomography/CT was significantly associated with LNM. Conclusion Lymph node diameter and maximum standardized uptake value predicted LNM in patients with resectable ICC. Preoperative lymph node evaluation can ensure optimal treatment.