Background: Surgical management of intrahepatic cholangiocarcinoma routinely includes resection of the hepatic parenchyma, yet the role of lymphadenectomy (LND) is more controversial. The objective of the current study was to define overall utilization, as well as temporal trends, in the utilization of LND among patients undergoing curative-intent hepatectomy for ICC using a nationwide database.
Materials and methods: One thousand four hundred ninety-six patients who underwent curative-intent resection for ICC were identified using the SEER database from 2000 to 2013. The utilization of LND was assessed over time and by geographic region. LND utilization and the incidence of lymph node metastasis (LNM) were evaluated relative to AJCC T categories.
Results: At the time of surgery, slightly over one-half of patients (n = 784, 52.4%) had at least one LN evaluated. Specifically, 613 (41.0%) patients had 1-5 LNs evaluated, whereas 171 (11.4%) patients had ≥ 6 LNs evaluated. The proportion of patients who had at least one LN evaluated at the time of surgery did not change with time (2000-2004: 50.5% vs. 2005-2009: 52.0% vs. 2010-2013: 53.7%) (p = 0.636). In contrast, the proportion of patients who had ≥ 6 LNs examined did increase (2000-2004: 6.9% vs. 2005-2009: 10.6% vs. 2009-2013: 14.3%) (p = 0.003). The risk of LNM was higher among patients with advanced T category tumors (Referent T1; T2a: OR 4.2, 95% CI 2.0-8.8, p < 0.001; T2b: OR 2.4, 95% CI 1.1-4.9, p = 0.018; T3: OR 3.6, 95% CI 1.6-7.9, p = 0.001; T4: OR 2.2, 95% CI 1.0-4.9, p = 0.049). In addition, the portion of patients with LNM varied among the different T categories (T1, 23.2%, T2a, 55.3%, T2b, 42.0%, T3, 51.4%, and T4, 39.5%; p = 0.001).
Conclusions: Utilization of LND in the surgical management of ICC across the USA remained relatively low and did not change over the last decade. Selective utilization of LND may be problematic as T-stage was not a reliable predictor of nodal status with almost a quarter of patients with early stage disease having LNM.
Keywords: Intrahepatic cholangiocarcinoma; Lymphadenectomy; Prognosis; Seer.