Lymph Node Dissection in Intrahepatic Cholangiocarcinoma: a Critical and Updated Review of the Literature

Background : Lymphatic spread of intrahepatic cholangiocarcinoma (iCCA) is common and negatively impacts survival. However, the precise role of lymph node dissection (LND) in oncologic outcomes for patients with intrahepatic cholangiocarcinoma remains to be established. Methods: Updated evidence on the preoperative diagnosis and prognostic value of lymph node metastasis is reviewed, as well as the potential benefit of LND in patients with iCCA. Results: The ability to accurately determine nodal status for iCCA with current imaging modalities is equivocal. LND has prognostic value for both survival and disease recurrence. However, execution rates of LND are highly varied in the literature, ranging from 26.9 to 100%. At least 6 lymph nodes should be examined from nodal stations of the hepatoduodenal ligament and hepatic artery as well as based on the location of the primary tumor. Neoadjuvant therapies may be beneficial if lymph node metastases at diagnosis are suspected. Surgeons performing a minimally invasive approach should focus on increasing LND rates and harvesting ≥ 6 lymph nodes. Lymph node negativity is required in patients with iCCA being considered for liver transplantation under investigational protocols. Conclusion: Despite an upward trend in the LND rate, the reality is that only 10% of patients with iCCA receive an adequate LND. This review underscores the importance of routinely increasing the rate of adequate LND in these patients in order to achieve accurate staging, appropriately select patients for adjuvant therapy, and improve the prognosis of clinical outcomes. While prospective data is lacking, the therapeutic impact of LND remains unknown.