Clinicopathological features and lymph node metastases characteristics of intrahepatic cholangiocarcinoma: a multicenter retrospective study (A report of 1 321 cases)

Abstract

Objective To analyze the clinicopathological features and lymph node metastases characteristics of intrahepatic cholangiocarcinoma (ICC). Methods The retrospective case-control study was conducted. The clinicopathological data of 1 321 ICC patients who were admitted to 12 hospitals from April 2007 to November 2017 were collected, including 182 in the Eastern Hepatobiliary Surgery Hospital of the Second Military Medical University, 173 in the First Affiliated Hospital of Xi′an Jiaotong University, 156 in the First Hospital Affiliated to Army Medical University (Third Military Medical University), 139 in the Cancer Center of Sun Yat-sen University, 128 in the Zhongshan Hospital of Fudan University, 113 in the Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine, 109 in the First Affiliated Hospital of Dalian Medical University, 84 in the Tianjin Medical University Cancer Institute and Hospital, 65 in the First Affiliated Hospital of Zhengzhou University, 62 in the Affiliated Hospital of North Sichuan Medical College, 58 in the Affiliated Drum Tower Hospital of Nanjing University Medical School and 52 in the Second Affiliated Hospital of Zhejiang University School of Medicine. Treatment planning was respectively determined by comprehensive hospitals according to clinical features and results of related examinations. Surgical procedures were performed based on the results of intraoperative examinations and patients′ conditions. Observation indicators: (1) laboratory examination and treatment situations; (2) relationship between clinicopathological features and primary tumor location and diameter; (3) diagnosis of lymph node dissection and metastases; (4) relationship between clinicopathological features and lymph node metastases. Measurement data with normal distribution were represented as ±s, and comparison between groups was done by the t test. Measurement data with skewed distribution were described as M (range). Comparison of count data were analyzed using the chi-square test. Results (1) Laboratory examination and treatment situations: of 1 321 patients, cases and percentages of positive hepatitis B virus (HBV), positive serum alpha-fetoprotein (AFP) (>20 μg/L), positive serum carcinoembryonic antigen (CEA) (>5 μg/L), positive serum alanine transaminase (ALT) (>75 U/L), positive serum CA19-9 (>37 U/mL) and positive serum total bilirubin (TBil) (>20 μmol/L) were respectively 202, 80, 329, 207, 590, 300 and 15.586% (202/1 296), 7.339%(80/1 090), 26.299% (329/1 251), 16.587% (207/1 248), 49.789%(590/1 185), 24.000% (300/1 250). Of 1 321 patients, 1 206 underwent surgery, including 904 with hepatectomy, 193 with transcatheter arterial chemoembolization (TACE), 72 with percutaneous transhepatic biliary drainage (PTBD), 3 with endoscopic retrograde cholangiopancreatography (ERCP), 3 with PTBD + ERCP and 31 with other treatments; 115 had missing registration of surgical procedures. (2) Relationship between clinicopathological features and primary tumor location and diameter: ① Relationship between clinicopathological features and primary tumor location: cases with CA19-9 level ≤ 37 U/mL, 38-200 U/mL and > 200 U/mL were respectively 227, 91, 146 with primary tumor located in left liver and 282, 134, 137 with primary tumor located in right liver. Cases combined with hepatitis and intrahepatic bile duct stone were respectively 67, 73 with primary tumor in left liver and 111, 47 with primary tumor in right liver, with statistically significant differences in above indictors (χ2=6.710, 5.656, 12.534, P 5 cm were respectively 159, 250, 229 with CEA level ≤ 5 μg/L and 40, 65, 95 with CEA level > 5 μg/L and 165, 258, 286 with ALT level ≤ 75 U/L and 34, 57, 36 with ALT level > 75 U/L and 148, 242, 281 with TBil level ≤ 20 μmol/L and 51, 73, 43 with TBil level > 20 μmol/L, and 37, 70 and 131 patients had satellite loci of tumor, with statistically significant differences in above indictors (χ2=8.669, 6.637, 15.129, 34.746, P 5 cm, 48.790%(121/248) in patients with CEA ≤ 5 μg/L, 59.302%(51/86) in patients with CEA > 5 μg/L, 40.234%(103/256) in patients with TBil ≤ 20 μmol/L, 35.106%(33/94) in patients with TBil > 20 μmol/L, with statistically significant differences in above indictors (χ2=5.078, 6.262, 9.456, 5.156, P<0.05). Conclusions The related etiological factors may be different due to different primary location of ICC. Primary tumor in left liver is significantly associated with intrahepatic bile duct stone of left liver, and primary tumor in right liver is associated with combined hepatitis, while combined hepatitis could lead early occurrence of ICC. At present, there is a low rate of lymph node dissection in ICC patients and a high lymph node metastasis rate in patients receiving lymph node dissection. Lymph node metastasis is associated with primary tumor location and diameter, levels of CEA and TBil. Lymph node metastasis rate in left liver is higher than that in right liver, and is getting higher with increased primary tumor diameter. Key words: Biliary tract neoplasms; Intrahepatic cholangiocarcinoma; Lymph nodes metastases; Multi-center; Retrospective study