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RESECTION OPTIONS
133
Once the right lateral fissure has been demonstrated by demarcation, dissec-
tion should take place as far medially as possible to avoid damage to the right
hepatic veins ( Fig. 3.32 ). Again their course and safety can be assessed using
intraoperative ultrasound.
Extended right hepatectomy (Segments IV–VIII)
Mobilization occurs in the usual fashion; the caudate lobe (caudate lobe resec-
tion is optional) if being included is freed from its caval attachments left-to-right.
The dissection of Segment IV sheath is performed and Segment IV mobilized
away from adjoining Segment III ( Fig. 3.33 ). At this stage the right sheath can be
stapled followed by the right hepatic vein. The boundary of the discolouration is
along the medial border of Segment V. If a full mobilization of the liver from the
IVC has been performed there is little risk of significant bleeding. A danger arises
when small venous vessels are avulsed from the cava at the superior and posterior
aspect of the resection. Access is difficult and control can be lost. The important
point with all right-sided resections and particularly an extended right is to have
complete caval clearance and mobilization before liver resection commences.
Non-traditional options
With the liver now defined as eight variable segments, the potential to minimize
loss of functional mass is improved. The aim of the surgeon is to remove all tumour
within the liver but leave enough functional parenchyma for patient survival.
Fig. 3.31 For an extended
left hepatectomy it is
necessary to staple across
the left main sheath and
ligate the sheaths to
Segments V and VIII. The
left hepatic vein is stapled
and middle hepatic vein
ligated, divided, and
oversewn as a stapler in
this position is rarely a
practical option.
LIVER
134
Fig. 3.32 The line of resection for an extended left hepatectomy leaving only
Segments VI and VII.
Fig. 3.33 For an extended
right hepatectomy, the
caval connections need to
be fully ligated, the right
main sheath stapled, and
the middle hepatic vein
(in sling) and right hepatic
veins identified and divided
after mobilizing segment
IV from its inflow sheath.
The number of clinical scenarios possible is infinite but a broad understand-
ing of the possible techniques needs to be appreciated.
Staged procedures ( Fig. 3.34 – 3.38 )
Surgery can sometimes be directed to clear one lobe of the liver (usually the
left) of all known disease. After an interval of 6–8 weeks when regeneration of
RESECTION OPTIONS
135
the liver has occured, a more major resection (usually a formal right hepatec-
tomy), to clear residual disease on the right hand side is performed.
Staged resections are usually only possible if the left side can be cleared first.
This is because of the need to remove as little normal parenchyma as possible
to avoid stimulating too much regeneration, which occurs after the second
resection when all tumour has been removed.
The stimulus for regeneration also stimulates tumour growth, which even
with chemotherapy may be uncontrollable. The resection of tumour without
much additional normal liver parenchyma is achieved by local resections on
the left, which is facilitated by its smaller size (principally thickness). This is
generally impossible on the right side unless there is an extremely unusual
distribution of lesions where they are all peripheral and accessible. As a result,
a right-sided resection necessarily removes a greater amount of normal liver
tissue (Garcea et al ., 2008b ).
Portal vein embolization ( Figs. 3.39 – 3.41 )
For difficult bilateral metastases another approach is portal vein embolization
(performed radiologically or surgically), which enhances regeneration of the
cleared side while the affected and embolized side atrophies (Elias et al ., 1999a , b ;
Azoulay et al ., 2000 ; Adam et al ., 2004 ; Capussotti et al ., 2008 ) ( Fig. 3.40 ).
The atrophic side is then resected (similar to the protocol for staged proce-
dures) ( Fig. 3.41 ).
Whilst theoretically an appealing concept, once performed, embolization
can stimulate deposits on the untreated side and the growth of the metastases
can exceed that of the remnant, making further surgery futile (Elias et al .,
1999b ). This is similar to the problem with staged procedures but because the
Fig. 3.34 Widely dispersed
disease within the liver.
LIVER
136
Fig. 3.36 The liver is
allowed to regenerate over
a 6-8 week period.
Fig. 3.37 The patient
undergoes a standard
right hepatectomy.
Fig. 3.35 All tumours on
the left side of the liver
resected or ablated to
remove ‘known’ left-sided
disease. The right side is
undisturbed.
RESECTION OPTIONS
137
majority of the blood supply to the tumour deposits is derived from the hepatic
artery and its branches, portal vein embolization stimulates significant liver
regeneration while preserving the tumour circulation, therefore not stimulating
further growth (Wicherts et al ., 2008 ).
Ablation
Most surgical centres were initially very enthusiastic about the possibilities
offered by ablative techniques (radiofrequency, electrolysis, microwave, or
laser ablation) (Lau and Lai, 2009 ). They are certainly an attractive concept
and it was hoped that results equivalent to open surgery could be achieved.
Certainly some centres have reported reasonable long-term results for radio-
frequency ablation—46% at 3 years (Solbiati et al ., 2001 ); 37% at 3 years
Fig. 3.38 The residual liver
regenerates to a volume
similar to that pre-resection.
Fig. 3.39 Diffusely involved
liver with bilateral metas-
tases.
LIVER
138
(Abdalla et al ., 2004 )—but these results are not equivalent to the best now
being obtained by surgical resection (Fong et al ., 1999 ; Minagawa et al ., 2000 ;
Belli et al ., 2002 ; Choti et al ., 2002 ). Nevertheless it still remains an excellent
percutaneous treatment in patients who are not fit for open or laparoscopic
surgery (Bruix et al ., 2001 ) although when patients are operable, even with
hepatocellular cancer, results are better for open resection (Vivarelli et al .,
2004 ). It is clear that ablative treatments (of whatever variety) have not yet
established a clear position in the surgical armamentarium and this is in part
because surgeons can usually successfully resect lesions more reliably and
achieve more certain and precise clearance than with ablation. The initial hope
that awkward central lesions would be suitable for ablation has not been real-
ized because of the problems encountered when using heat or cooling to
achieve ablation when the risk of damage to major veins or bile ducts is con-
siderable and major vessels act as heat sinks and reduce the efficiency. Ablation
of lesions in one lobe combined with resection of the other affected lobe may
offer promise in some situations (Abdalla et al ., 2004 ).
Fig. 3.41 The atrophic
right lobe is resected leaving
the hypertrophied left
lobe.
Fig. 3.40 A right portal
vein embolization to pro-
duce atrophy of the right
lobe and compensatory
left-sided hypertrophy.
RESECTION OPTIONS
139
Local excision ( Figs. 3.42 and 3.43 )
Wedge resections of metastatic deposits, have been viewed by the purists as
‘poor man’s’ surgery but this fails to recognize the reason behind the original
push for anatomical resections which was to gain clear margins.
If adequate clearance can be achieved (of greater than 5mm), then local
resections have the same long-term outcome as more major resections (Sarpel
et al ., 2008 ). The mistake is to underestimate how difficult they can be. Deposits
around the liver edge are readily removed with a wedge resection but the
more centrally placed lesions often require as much skill and time as a liver
resection.
Lesions on the surface, particularly of Segment VII and VIII, can be very dif-
ficult to remove with safe control of the bleeding at the base of the resection. It
Fig. 3.42 Diffusely
involved liver again with
bilateral metastases.
Fig. 3.43 A combination
of wedge resections and
ablations with a segmental
resection of Segments V
and VI.
LIVER
140
should not be viewed as an easy option, rather one that is intended to preserve
more liver substance.
Synchronous colon and liver resection
It is not unusual for patients to present with primary colon cancer and synchro-
nous resectable liver metastases. While the patient often wants the condition
definitively managed at the one operation, and it is occasionally possible with
small volume disease, this is not our usual policy. Previously it was always felt
that these patients had a worse outlook (Scheele et al ., 1995 ) but reports have
certainly appeared showing excellent results with combined procedures,
although there remain relatively few patients in total (Vogt et al ., 1991 ). Results
even in more recent reports are clearly less favourable in older patients where
synchronous procedures should not be considered (Tanaka et al ., 2004 ). We
generally prefer to do the colonic surgery first, assessing the liver at the time of
surgery with intraoperative ultrasound and palpation, and then reassess at
3 months (frequently with chemotherapy in the interim). If there is no further
dissemination or progression of the intrahepatic disease, rendering it inoper-
able, then we proceed to liver resection. On occasions, small lesions may be
removed from the liver at the time of the colon resection but this is only done
if all the disease can be cleared at that time, or if a staged procedure is going to
be required and the left side can be cleared. If combined procedures are to be
undertaken then both should follow sound oncological principles and the
patient must be fully consented, and warned about the potential risk of anas-
tomotic complications in the presence of a major liver resection. If this is to be
undertaken then one should consider performing a defunctioning temporary
stoma, which is a safe option that removes the potential for the life-threatening
complications that would result from a colonic leak.
Laparoscopic liver surgery
With increasing confidence with laparoscopic liver resection, more cases are
now deemed appropriate for this approach. While isolated centres are report-
ing excellent results for a varity of resections including formal left and right
hepatectomies (Buell et al ., 2008 ; Nguyen et al ., 2008 ), most surgeons have not
yet embraced it for larger resections. It does, however, offer an option for
patients with peripherally located liver lesions and minimal or moderate
peritoneal adhesions (Buell et al ., 2008 ). With more patients now undergoing
laparoscopic colon resections, the extent of peritoneal adhesions is markedly
reducing, making many patients with colorectal liver metastases reasonable
candidates for laparoscopic resection. Peripheral hepatocellular cancers,
RE-DO SURGERY
141
adenomas, and non-colorectal metastatic deposits can all now be resected
laparoscopically, aided by the array of new equipment that is being specifically
developed (Belli et al ., 2004 ). Certainly the availability of laparoscopic staplers,
harmonic scalpels, argon coagulators, and tissue glues has facilitated the devel-
opment of this new approach. The addition of a hand-port provides added
security to control haemorrhage and provides an exit route for the specimen
(Robles et al ., 2008 ). The ability to fully mobilize and assess the liver is com-
promised but close follow-up will usually detect small lesions missed at initial
surgery.
Follow-up
The optimal follow-up regimen remains to be determined and no regimen has
been conclusively shown to improve survival despite the fact that some centres
employ CT scanning and carcinoembryonic antigen (CEA) estimations (if
these were elevated at the original presentation of the primary tumour) every
3–4 months for 2 years then 6-monthly surveillance up to 5 years. However,
close observation is useful in detecting the small group of fit patients that will
benefit from a further liver resection, and results in this cohort are encourag-
ing. At least 6-monthly scans for 2 years and then yearly up to 5 years should
be performed. There is a belief that the use of oxaliplatin has altered the natu-
ral history of this phase and there appears to be a small but increasing number
of patients with later recurrences beyond 5 years and in the future these rec-
ommendations are likely to change. Early recurrence within the first 12 months
is a very poor prognostic feature in colorectal cancer metastases (Kjeldsen
et al ., 1997 ; Schoemaker et al ., 1998 ; Kim et al ., 2008 ). All patients are also seen
if any symptoms develop. Late recurrence of metastasis is more encouraging
and some of these patients will be candidates for further treatment (Vigano
et al ., 2008 ).
Re-do surgery
As a result of close follow-up, patients will be found with recurrent lesions
isolated to the liver. Assessment should aim to find evidence of metastatic dis-
ease outside the liver and CT and positron emission tomography (PET) scan-
ning are valuable (Ogunbiyi et al ., 1997 ). If isolated liver disease is confirmed
then the patient can be considered for reoperation. The operative approach
needs to consider the consequences of previous surgery, including the hyper-
trophy that will have occurred following a major resection. Left lobe resection
with subsequent right lobe hypertrophy can lead to a more inferiorly based
and medially shifted portal triad making the origin of the right hepatic pedicle
LIVER
142
deeper and more medial than expected. Similarly, a right hepatectomy with
subsequent left lobe hypertrophy will often push the hilum more anteriorly
(Bozzetti et al ., 1992 ; Adam et al ., 1997 ; Petrowski et al ., 2002 ).
This is further complicated by a difficult dissection of adhesions in order to
gain access to the liver. Mobilization can take several hours of careful dissec-
tion and considerable blood loss is possible even before the liver resection is
attempted. Although the liver often attains a similar volume to that preopera-
tively, the liver substance is often not the same as at the time of the first liver
resection, being more friable and holding sutures poorly. It is important to
critically evaluate the CT scans in the context of the previous liver resection.
For example, posterior lesions to the right of the cava after a right hepatectomy
cannot be brought forward, as in a Segment VII lesion, as they are plastered to
the posterior aspect of the abdominal cavity diaphragm and are better
approached with a patient on their left side and a thoraco-abdominal incision.
This is never used for ‘first time’ liver surgery. However, with careful planning
and adequate operative time, the outcome for these redo patients is compara-
ble to first time operations (Petrowski et al ., 2002 ; Sa Cunha et al ., 2007 ; Garcea
et al ., 2008 b).
Liver tumours
Investigation of a hepatic mass ( Fig. 3.44 )
With the increased availability of ultrasound, CT, and magnetic resonance
imaging (MRI) scanning incidental hepatic masses are being reported. The
predominant question to be answered is whether the mass is benign, malig-
nant, or has malignant potential. Investigations are directed towards answer-
ing this question without the need for a biopsy except in cases where surgery is
not a realistic option or the expectation of benign pathology is high. In the case
of hepatic adenoma and cystadenoma, if biopsy can be safely performed then
it is reasonable.
For indeterminate lesions, a CT is usually required if this has not been done
at the time of presentation and together with the clinical history and tumour
markers (CEA, CA 19.9, and alpha feto-protein) will exclude the majority of
sinister pathologies. A simple cyst requires no further treatment. Complex sep-
tated or irregular cysts in the presence of a normal CA 19.9 may benefit from
aspiration and estimation of fluid CA 19.9 (depending on the clinical setting).
Solid lesions often pose more of a diagnostic challenge particularly when they
have no specific radiological features such as a central scar in focal nodular
hyperplasia or the typical vascular pattern seen on MRI for haemangiomas.
These lesions will need further investigation and are discussed in later sections.