Objective To analyze the impact of lymph node dissection on textbook outcomes (TO) and the prognosis of intrahepatic cholangiocarcinoma (ICC).

Methods The retrospective cohort study was conducted. The clinicopathological data of 376 ICC patients who underwent hepatectomy in 4 medical centers, including Mengchao Hepatobiliary Hospital of Fujian Medical University et al, from December 2011 to December 2017 were collected. There were 242 males and 134 females, aged 57(range, 48-63)years. According to the criteria of TO, patients were classified as two cate⁃gories, including patients achieving TO and not achieving TO. Measurement data with normal distri-bution were represented as Mean±SD, and comparison between groups was conducted using the independent sample t test. Measurement data with skewed distribution were represented as M(range) or M(Q₁,Q₃), and comparison between groups was conducted using the Mann⁃Whitney U test. Count data were represented as absolute numbers, and comparison between groups was conducted using the chi‑square test, Yates adjusted chi‑square test or Fisher exact probability. Comparison of ordinal data was conducted using the non-parameter rank sum test. Univariate and multivariate analyses were conducted using the Logistic regression model. The Kaplan‑Meier method was used to draw survival curve. Survival analysis was conducted using the Log‑rank test.

Results (1) TO situations. Of the 376 ICC patients who underwent hepatectomy, 199 cases achieved TO, including 40 cases with lymph node dissection and 159 cases without lymph node dissection, 177 cases did not achieve TO, including 76 cases with lymph node dissection and 101 cases without lymph node dissection. (2) Influencing factors for TO after hepatectomy of ICC patients. Results of multivariate analysis showed that lymph node dissection, microvascular invasion, nerve invasion and the volume of intraoperative blood loss >800 mL were independent risk factors for achieving TO after hepatec-tomy of ICC patients (odds ratio=2.22, 2.95, 3.58, 4.09,95% confidence interval as 1.34-3.69, 1.43-6.07, 1.40-9.17, 1.35-12.43, P<0.05). Of the 116 patients with lymph node dissection, 40 cases achieved TO, 103 cases achieved R₀ resection, 38 cases had postoperative complications, 67 cases had delayed hospital stay. The above indicators were 159, 255, 41, 65 of 260 patients without lymph node dissection. There were significant differences in the above indicators between patients with and without lymph node dissection (χ²=22.90, 15.16, 13.95, 37.78, P<0.05). (3) Follow‑up. All the 376 patients were followed up for 19(range, 1-74)months. Of 199 patients achieving TO, the 1‑, 2‑and 3‑year survival rates of 40 patients with lymph node dissection were 54.0%, 36.6% and 26.1%, respectively, versus 67.7%, 42.7% and 34.4% of 159 patients without lymph node dissection, showing no significant difference between them (χ²=1.89, P>0.05). Of 177 patients not achieving TO, the 1‑, 2‑and 3‑year survival rates of 76 cases with lymph node dissection were 58.9%, 25.7% and 10.3%, respectively, versus 53.0%, 28.5% and 17.2% of 101 cases without lymph node dissection, showing no significant difference between them (χ²=0.25, P>0.05).

Conclusions Lymph node dissec-tion, microvascular invasion, nerve invasion and the volume of intraoperative blood loss >800 mL are independent risk factors for achieving TO after hepatectomy of ICC patients. Lymph node dissec-tion may increase the postoperative complication rate, prolong the hospital stay and decrease the rate of achieving TO. However, it does not affect the prognosis of patients.