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Page 2 of 7 Kim et al. Hepatoma Res 2021;7:31 https://dx.doi.org/10.20517/2394-5079.2021.09

risk [2,9,10] . In cases of large tumor, complete resection with a sufficient margin could be difficult to achieve,
and combined resection with adjacent hemi-liver or other segments can be considered in patients with good
liver function. However, many patients with HCC have chronic hepatitis or cirrhosis, and should undergo
isolated caudate lobectomy as an alternative procedure of choice to improve curability [1,11,12] .

With the accumulation of experiences, development of surgical instruments and advancement of surgical
skills, pure laparoscopic liver resection is possible in tumors located in all segments of the liver and in
patients with liver cirrhosis [13-17] . However, despite the advances in laparoscopic liver surgery, resection of
the caudate lobe is still one of the most technically challenging surgeries due to its deep location and
proximity to major vessels including inferior vena cava (IVC), hepatic veins and hepatic hilum. For these
reasons, laparoscopic caudate lobectomy has been performed in only a few experienced centers.
Nervertheless, safety and feasibility of this procedure, when performed by experienced surgeons, have been
reported by several experienced centers [18-25] .

The aim of this article is to review the global experiences of laparoscopic caudate lobectomy for HCC
regarding the indication, technical access, surgical and oncologic outcomes based on a literature review.
Literature searches were conducted using PubMed and Cochrane Library databases with terms of “Isolated
caudate lobectomy”, “Laparoscopic caudate lobectomy”, and “Hepatocellular carcinoma in caudate lobe”.

ANATOMY OF THE CAUDATE LOBE
The caudate lobe is located posterior to the right and left lobes of liver and anterior to the IVC, which may
envelop this structure circumferentially. A nomenclature system for the anatomy of the caudate lobe had
been debated before Kumon’s subdivision classification system was established. Topographical
[26]
nomenclature used for hepatic segments in the United States was proposed by Healy and Schroy : segment
[27]
I left and segment I right, while nomenclature used in Europe was proposed by Couinaud : segment I and
[28]
segment IX. However, Kumon classified the caudate lobe into 3 portions through the investigation using
corrosion liver casts and this classification has been widely used.
The caudate lobe is an autonomous segment of the liver; it consists of 3 parts according to Kumon’s
[28]
nomenclature: the Spiegel lobe, the paracaval portion, and the caudate process . The Spiegel lobe is located
to the left of the retrohepatic IVC and the Arantius’ ligament. The paracaval portion is anteriorly attached
to the retrohepatic IVC by the retrohepatic ligament and the short hepatic veins. The caudate process is
located anterior to the IVC, extending to the hilum of the liver just posterior to the bifurcation of the portal
vein.

The portal blood flow for the caudate lobe origins from both the left and the right portal systems. According
to Kumon’s study, there are usually 5 (mean 4.3, range 3-6) portal venous branches and 3 (mean 3.8, range
2-6) biliary branches in the caudate lobe. The hepatic arterial flow is variable, but usually comes through a
solitary branch from the main left hepatic artery and a second smaller branch from the right posterior
sectional artery. A single portal vein and bile duct arising from the left branch are most commonly found in
the Spiegel lobe. A single branch from the left portal vein predominantly feeds the paracaval portion but the
bile duct drains to the right or left system in almost equal frequencies. And for the caudate process, the
portal vein usually branches from the right portal vein and the bile duct from the right posterior hepatic
[28]
duct . Venous drainage occurs along the posterior aspect of the caudate lobe directly into the IVC through
multiple short hepatic veins which vary in number and size .
[29]