Page 19 - Read Online

Page 2 of 10 Naeem et al. Hepatoma Res 2018;4:18 I http://dx.doi.org/10.20517/2394-5079.2018.22

patients, image guided local ablation has provided a viable curative option that has significantly prolonged
survival and improved cure rates .
[2]

As the fourth leading cause of cancer related deaths in the world , hepatocellular carcinoma remains one
[3]
of the most feared complications of liver cirrhosis to date. The tremendously high case-fatality rate of this
malignancy is often attributed to the relatively advanced stage of disease at the time of diagnosis in most
cases . Although adoption of intensive surveillance programs for patients with underlying chronic liver
[3,4]
disease have allowed for earlier detection of HCC , prognosis remains poor for most patients, as evidenced
[5]
by the short median survival following diagnosis, ranging from 6-20 months . Nevertheless, most guidelines
[6]
recommend screening at-risk individuals, such as those with chronic liver disease, with a non-invasive and
cost-effective radiological investigation like ultrasound every 6 months.

HCC arises most often in the setting of cirrhosis, with an incidence of HCC development being as high as 1%-8%
per year in chronic liver disease patients. Furthermore, the disease prevalence has been found to reflect the
geographical distribution of the risk factors for cirrhosis . Areas with a high prevalence rate include Eastern
[7]
Asia and Sub-Saharan Africa due to the presence of chronic HBV infection, which is considered to be the
dominant risk factor for chronic liver disease .
[8,9]
Optimal therapeutic approach is individualized to each patient, and should ideally be determined by a
multi-disciplinary team comprising of hepatologists, surgeons, oncologists, radiologists, interventional
radiologists and pathologists due to the complexity of the disease. Factors that need to be considered when
determining treatment approach include liver function, size and number of nodules, tumour extension, age
and co-morbid conditions of the patient. Nature of the underlying chronic liver disease may also play a part
in this decision, particularly in cases where the oncogenic agent is expected to persist following treatment,
reducing the viability of invasive procedures like surgical resection.

Guidelines such as The European Association for the study of Liver and The American Association for the
Study of Liver Diseases recommend algorithms based on the Barcelona Clinic Liver Cancer staging system
for the purpose of staging and treatment allocation. Although it has a number of limitations, the BCLC
staging system has been validated in different settings and is commonly employed in many countries . The
[10]
algorithm stratifies patients into five categories, based on the disease stage. In general, potentially curative
treatments such as tumor resection, liver transplantation and percutaneous ablation are reserved for patients
with early stage disease, classified as BCLC stage 0 and BCLC stage A, while patients in BCLC stage B, C and
D presenting with advanced disease are offered palliative treatment options like chemoembolization and
Sorafenib or supportive care [Figure 1].

Since their introduction, The Milan Criteria have become the standard guidelines for hepatic transplantation .
[11]
These criteria restrict liver transplant to patients with either a single tumor less than 5 cm in diameter
or less than three foci of tumor each with a diameter of no more than 3 cm, absence of angio-invasion
and extra hepatic involvement. Using these criteria, excellent 5-year survival rates of 70% or greater and a
15% recurrence rate have been demonstrated by multiple studies, indicating their importance in predicting
prognosis in HCC patients undergoing liver transplant. The Milan Criteria has also been found to produce
excellent results when used for treatment allocation of patients with early stage disease, who may be
candidates for other curative procedures like surgical resection or loco-regional ablative treatments

PERCUTANEOUS LOCAL ABLATION
Since their advent in the 1990s, percutaneous local ablative techniques have been continuously evolving
owing to rigorous research and clinical testing in this area . While percutaneous ethanol injection was
[12]
regarded as the primary ablative therapy up until the turn of the century, recent years have seen it largely