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Page 4 of 8 Golhar et al. Mini-invasive Surg 2019;3:9 I http://dx.doi.org/10.20517/2574-1225.2018.58

TECHNICALLY COMPLEX SITUATIONS
For centrally located or deep tumors, visual guidance and tactile feedback are limited, and IOUS may
be essential for tumor localization, assessment for satellite nodules, planning the resection plane and
[13]
determining spatial relationship of the tumor with major blood vessels . Sub-capsular tumors can be
identified by intra-operative fluorescence imaging following preoperative intravenous injection of ICG
[10]
(0.5 mg per kg body weight) usually given within two weeks of surgery . “Diamond technique” has been
[17]
described for centrally located parenchymal sparing liver resection .
Anatomic liver resection for tumors located in postero-superior (segment 7, segment 8) segments and
segment 4a are technically difficult because of difficulty of access and are associated with more blood loss,
risk of conversion to open surgery or change to hemi-hepatectomy [18-21] . Strategies such as use of a spacer,
left lateral position, intercostal ports, hand-assisted, robot-assisted or other approaches have demonstrated
reduced blood loss and need for conversion in such tumors [18-21] .

Only few cases of isolated laparoscopic caudate lobe resection are reported as it is technically challenging [22,23] .
Laparoscopy provides good vision of the caudate lobe between the hilar plate and the vena cava from
the right side. Division of the gastro-hepatic ligament facilitates visualization and resection from the left
side [22,23] . LLR is safe and non-inferior to OLR in the cirrhotic liver too, with lesser blood loss and shorter
[24]
hospital stay reported in few studies .

LLR DIFFICULTY SCORING SYSTEMS AND SELECTION CRITERIA
[25]
The degree of difficulty of LLR depends upon multiple factors . A retrospective analysis has found a
good agreement between the difficulty level assessed by the surgeon and a difficulty index based on tumor
[25]
location, extent of liver resection, tumor size, proximity to major vessels, and liver function . Although
such scoring systems need further refinement and prospective validation, they can be helpful in assessment
[25]
of trainee surgeon’s skills, guide their training, better estimate risks of the procedure . Appropriate
[25]
patient selection, practicing and honing LLR skills is paramount for success . Most laparoscopic liver
surgeons would accept tumor size of < 5 cm, fewer than three lesions without macroscopic vascular
invasion or the need for biliary reconstruction as criteria for LLR [2,26] .

RESULTS OF LAPAROSCOPIC VERSUS OPEN HEPATECTOMY
Short term outcomes
Comparison of LLR and OLR
LLR has been found to be significantly better compared to OLR for minor hepatectomies for short-term
[27]
outcomes such as the operation time, blood loss, and post-operative hospital stay . Although there are
numerous case-reports and retrospective series of LLR, few well-designed randomized controlled trials
(RCTs) and meta-analyses are currently available [27-35] . Meta-analyses show that LLR has clinical benefits
over OLR with significant reduction in blood loss, blood transfusion, complications and hospital stay with
comparable operative time and resection margin positivity. However potential biases due to low statistical
power of many studies included in the meta-analyses cannot be undermined [28-35] . The results of these
studies are summarized in Table 2.

Long term outcomes
Hepatocellular carcinoma
Current evidence suggests that local tumor recurrence, disease free survival and overall survival are similar
between laparoscopic and open resections [39-42] . The results of these studies are summarized in Table 3. Although
meta-analyses indicate that LLR for hepatocellular carcinoma (HCC) is comparable to OLR in oncological
and survival outcomes, they lacked RCTs [36-39] .