Published online Apr 28, 2019. doi: 10.3748/wjg.v25.i16.1986
Peer-review started: February 6, 2019
First decision: March 5, 2019
Revised: March 14, 2019
Accepted: March 24, 2019
Article in press: March 24, 2019
Published online: April 28, 2019
Regional lymph node metastasis in patients with hepatocellular carcinoma (HCC) is not uncommon, and is often under- or misdiagnosed. Regional lymph node metastasis is associated with a negative prognosis in patients with HCC, and surgical resection of lymph node metastasis is considered feasible and efficacious in improving the survival and prognosis. It is critical to characterize lymph node preoperatively. There is currently no consensus regarding the optimal method for the assessment of regional lymph nodes in patients with HCC.
To evaluate the diagnostic value of single source dual energy computed tomography (CT) in regional lymph node assessment for HCC patients.
Forty-three patients with pathologically confirmed HCC who underwent partial hepatectomy with lymphadenectomy were retrospectively enrolled. All patients underwent dual-energy CT preoperatively. Regional lymph nodes (n = 156) were divided into either a metastatic (group P, n = 52) or a non-metastasis group (group N, n = 104), and further, according to pathology, divided into an active hepatitis (group P1, n = 34; group N1, n = 73) and a non-active hepatitis group (group P2, n = 18; group N2, n = 31). The maximal short axis diameter (MSAD), iodine concentration (IC), normalized IC (NIC), and the slope of the spectral curve (λHU) of each group in the arterial phase (AP), portal phase (PP), and delayed phase (DP) were analyzed.
Analysis of the MSAD, IC, NIC, and λHU showed statistical differences between groups P and N (P < 0.05) during all three phases. To distinguish benign from metastatic lymph nodes, the diagnostic efficacy of IC, NIC, and λHU in the PP was the best among the three phases (AP, PP, and DP), with a sensitivity up to 81.9%, 83.9%, and 81.8%, and a specificity up to 82.4%, 84.1% and 84.1%, respectively. The diagnostic value of combined analyses of MSAD with IC, NIC, or λHU in the PP was superior to the dual energy CT parameters alone, with a sensitivity up to 84.5%, 86.9%, and 86.2%, and a specificity up to 83.0%, 93.6% and 89.8%, respectively. Between groups P1 and P2 and groups N1 and N2, only IC, NIC, and λHU between groups N1 and N2 in the PP had a statistically significant difference (P < 0.05).
Dual-energy CT contributes beneficially to regional lymph node assessment in HCC patients. Combination of MSAD with IC, NIC, or λHU values in the PP is superior to using any single parameter alone. Active hepatitis does not deteriorate the capabilities for characterization of metastatic lymph nodes.
Core tip: Dual-energy computed tomography (CT) contributes beneficially to regional lymph node assessment in hepatocellular carcinoma (HCC) patients, which can differentiate metastatic and non-metastatic lymph nodes for improving regional lymph node staging of HCC. Combination of maximal short axis diameter with dual-energy CT quantifiable parameters (iodine concentration, normalized iodine concentration, or the slope of the spectral curve) in the portal phase can be more advantageous in regional lymph node assessment. Active hepatitis does not deteriorate the detection and characterization of metastatic lymph nodes in HCC.