The role of routine lymphadenectomy (LND) in the surgical treatment of intrahepatic cholangiocarcinoma (ICC) remains controversial. The investigators' multi-institutional retrospective study have showed an increasing adoption of LND among patients undergoing curative resection for ICC during the last decade. The current prospective and randomized study based on a multi-institutional collaboration would investigate whether routine LND would benefit patients in short- and long-term survival remains.

Intrahepatic cholangiocarcinoma (ICC) is the second most common primary liver cancer and its incidence is increasing worldwide.Resection of the primary ICC tumor site within the liver represents the best curative treatment option. However, the role of lymphadenectomy (LND) at the time of surgery remains controversial with some centers considering it standard while other surgeons perform LND only in select circumstances. The utilization of LND may not only vary among different institutions, but also by geographic region. Specifically, data from East and West centers have noted a variation in the utilization of LND ranging 27%-100%.While several case series from Asia have noted that most centers do not regularly perform LND,other data from the West suggest that LND may be becoming more routine. Despite the lack of consensus among surgeons, the American Joint Committee on Cancer (AJCC) Staging manual recommends that the nodal basin be staged. Disease-specific staging for ICC was first introduced in the 7th edition of the AJCC staging manual published in 2010. The newly updated 8th edition of the AJCC staging system now recommends that 6 lymph nodes be evaluated to stage a patient with ICC.

The previous multi-institutional retrospective study from the investigators have showed an increasing adoption of LND among patients undergoing curative resection for ICC during the last decade. The current prospective and randomized study based on a multi-institutional collaboration would investigate whether routine LND would benefit patients in short- and long-term survival remains.

Inclusion Criteria:

• Patients diagnosed with intrahepatic cholangiocarcinoma by imaging or biopsy
• The tumor is limited in the liver with no distant metastasis, and the primary disease is resectable
• Preoperative imaging (e.g. CT, MRI, PET-CT, etc.) and intraoperative exploration found no nodal swelling or enlargement

Exclusion Criteria:

• The primary disease is unresectable with or without distant metastasis
• The liver function or general condition of patients does not permit surgery
• Preoperative imaging (e.g. CT, MRI, PET-CT, etc.) and intraoperative exploration found obvious nodal swelling or enlargement, which indicates lymphadenectomy should be performed
• Patients aged below 18 or older than 65 would be excluded
• Pregnant women would not be enrolled

patients would not be told about the lymphadenectomy