Patterns and prognostic significance of lymph-node dissection for surgical treatment of peri-hilar and intrahepatic cholangiocarcinoma

BACKGROUND Lymph node (LN) metastasis is a major negative prognostic factor for intrahepatic (ICC) and peri-hilar (PCC) cholangiocarcinoma. Prognostic significance of LN dissection (LND), number of metastatic LN, LN stations and lymph-node ratio (LNR) are still under debate for cholangiocarcinoma. AIMS The aims of this study are to evaluate the prognostic value of LND, of the number of LNs harvested, of number of positive LNs, of LN stations and of LNR in ICC and PCC. METHODS Extension of LND, according with Japanese Society of Biliary Surgery (JSBS), number and status of harvested LNs were retro- spectively evaluated in patients cholangiocarcinoma submitted to surgical resection with curative intent between 1990 and December 2010. RESULTS One hundrend and thirty patients were submitted to surgical resection with curative intent; 61 were ICC and 69 PCC. Lymph-node dissection (LND) was performed in 71% of patients with ICC and in 96% with PCC. Median survival of patients with 0, 1 to 3 and more than 3 LNs retrieved was respectively 31, 37 and 36 months for ICC (p=0.53) and 3, 18 and 34 for PCC (p<0.01respectively. Median survival of patients with negative LN (N0) and with LN metastasis (N+) was 43 and 19 months in ICC (p=0.03) and 42 and 20 months in PCC (p=0.01), respectively. Median survival of patients with up to 3 N+ and more than 3 N+ was 52 and 7 months in ICC (p<0.01), and 26 and 11 months in PCC (p<0.01). Median survival of patients with LNR up to 0.25 and greater than 0.25 was 42 and 14 months in ICC (p= 0.01), and 37 and 11 months in PCC, respectively (p<0.01). At multivariate survival analysis LNR and macroscopic vascular invasion were significantly related to survival with hazard ratios of 3.00 (95% CI 1.69 - 5.34; p < 0.001) and of 1.90 (95% CI 1.17 - 3.07; p=0.009) respectively. CONCLUSIONS LN metastasis is a major prognostic factor for survival after surgical resection of ICC and PCC. Lymphadenectomy should be performed because number of LN retrieved and LNR showed high prognostic value. LNR can stratify patients with positive LNs and identify patients with not favourable prognosis that might be feasible of adiuvant therapy.