The hepatocarcinoma (Hepatocellular carcinoma) is a malignant tumor which is frequently associated to patients with chronic hepatopathy, commonly cirrhosis.
In patients with a sympromatic HCC, the overall survival doesn’t exceed several months. Multiple treatments have been proposed: Resection, liver transplantation, chemoembolization, and alcoholization. Independetly of the treatment, the efficacity of each one depends on the size of the tumor. That is the main reason why early diagnosis palys an important part in the management.
Lots of diagnostic methods have been developed for the diagnosis of HCC: Ultrasund, CT scan, MRI. Each one has it’s own problems, because none of them can diagnose the small nodules of hepatocellular carcinoma, and sometimes cannot differentiate regeneration nodules from HCC.
In the corrhotic patient, one can find a great amount of regeneration nodules. In the past, these nodules had different denominations, and that was the reason why the terminology was simplified in an international consensus (Hepatology 1995; 22: 992-993).
In patients with a sympromatic HCC, the overall survival doesn’t exceed several months. Multiple treatments have been proposed: Resection, liver transplantation, chemoembolization, and alcoholization. Independetly of the treatment, the efficacity of each one depends on the size of the tumor. That is the main reason why early diagnosis palys an important part in the management.
Lots of diagnostic methods have been developed for the diagnosis of HCC: Ultrasund, CT scan, MRI. Each one has it’s own problems, because none of them can diagnose the small nodules of hepatocellular carcinoma, and sometimes cannot differentiate regeneration nodules from HCC.
In the corrhotic patient, one can find a great amount of regeneration nodules. In the past, these nodules had different denominations, and that was the reason why the terminology was simplified in an international consensus (Hepatology 1995; 22: 992-993).
The cirrhotic nodule corresponds to a regeneration nodule without cellular atypia, surrounded by a septal capsule. It’s size doesn’t go beyond 3 mm, but we may find those reaching 8 mm. We can also find macronodules.
The dysplastic nodule is a lesion made up of hepatocytes surrounded by fibrosis with signs of dysplasia, but without crtieria of malignity. It’s size is usually inferior to 10 mm, but can reach 20 mm. One must not call them “ adenomatous hyperplasia “ or regeneration macronodule”. They must be classified as low or high grade dysplasia.
The third type of nodule is the HCC nodule. It is a nodule with cytological and hystological atypias, with crteria of malignity. There seems to be a relation between the cirrhotic nodule, the dysplastic nodule, the small HCC, and the sever HCC (Semin Liver Dis 1995; 15: 360-371; Hepatology 1992; 16: 949-955).
The smallest the nodule, more the chances of it being benign. This doesn’t exclude the possibility of HCC in small nodules. That is why size is not an absolut criteria. A criteria to differentiate between a cirrhotic nodule and HCC is the vascularization. The hepatic sinusoidal capillaries are irrigated by portal vein and branches or the hepatic artery. A benign nodule has a mixed vascularization, with a predomination of the portal flow. An HCC doesn’t have portal vascularization, but it’s irrigation depends on the arterial flow (neoangiogenesis). This is something that helps in their diagnosis (Radiology 1991; 178: 493-497).
The time for an HCC to double its size is about 112 days (Hepatogastroenterology 1993; 40: 311-315). It may occur soonr (<40 days) or much later (400 days). All these can make us understand why the difficulty of making an early diagnosis, specially in cirrhotic livers, and liver with an important amount of preserved architecture.
Imaging Studies
Ultrasound
Minimally invasive technique, with a low cost and common use. Has been used for more that 2 decades in the diagnosis of HCC. Small HCC’s are frequently hyperechogenic. But they may be hypo or isoechogenic.
Sometimes they may be surrounded by an hypoechogenic halo corresponding to the pseudocapsule, or may be heterogeneous with hypo or hyperechogenic zones inside the tumor. This characteristics are more frequently found in HCC, but are difficult to see in small nodules. Multiple studies have proposed the bi-annual follow-up with AFP dosages (J Hepatol 1994; 21: 1029-1034; J Hepatol 1994; 20: 65-71; Cancer 1996; 78: 977-985). These studies showed the success of this starategy.
CT scanning
One of the main characteristics of HCC’s is their almost exclusive arterial vascularization. After the contrast injection, during the arterial phase, hypervascular tumors can be easily viewed, when compared to the normal liver, which has mainly portal vascularization.
Hypervascular tumor apear hyperdense during the arterial phase, but in the mixed phase, they become isodense. The typical semiology of a small HCC is that of a small nodule, usually < 3 cm in diameter, visible only during the arterial phase (Radiology 1996; 199: 505-511). There are certain cases, hemochromatosis for example, when these nodules can be hypodense, but the density of the liver parenchyma is augmented.
The sensibility and specificity of this method for tumors 1-2 cm reaches 43%. But it can make the diagnosis of lesions as small as 1 cm.
Magnetic Resonance Imaging
The major interest in this method is due to its contrast potential, and the possibility of dynamic testing that can be repeated continually. The differential diagnosis between a regeneration nodule and a small HCC is difficult, specially in those cases with hyperintense nodules on T1 and not visible on T2. In these cases, a CT scan is recommended.
Follow-up of Patients with Liver Cirrhosis
To impact survival of HCC, one must fight for early diagnosis. This leads to high costs regarding patient management. This follow-up is helpful in patients with small HCC, Child A and some Child B cases, specially hemochromatosis, or patients who may undergo liver transplantation.
An augmentation of the AFP level is an indication for close follow-up. The usual follow-up consists of US and AFP levels every 6 months. We must remember that the size may double in the majority of cases in 4 months, so the follow-up can be performed every 4 months rather than every 6 months.
The dysplastic nodule is a lesion made up of hepatocytes surrounded by fibrosis with signs of dysplasia, but without crtieria of malignity. It’s size is usually inferior to 10 mm, but can reach 20 mm. One must not call them “ adenomatous hyperplasia “ or regeneration macronodule”. They must be classified as low or high grade dysplasia.
The third type of nodule is the HCC nodule. It is a nodule with cytological and hystological atypias, with crteria of malignity. There seems to be a relation between the cirrhotic nodule, the dysplastic nodule, the small HCC, and the sever HCC (Semin Liver Dis 1995; 15: 360-371; Hepatology 1992; 16: 949-955).
The smallest the nodule, more the chances of it being benign. This doesn’t exclude the possibility of HCC in small nodules. That is why size is not an absolut criteria. A criteria to differentiate between a cirrhotic nodule and HCC is the vascularization. The hepatic sinusoidal capillaries are irrigated by portal vein and branches or the hepatic artery. A benign nodule has a mixed vascularization, with a predomination of the portal flow. An HCC doesn’t have portal vascularization, but it’s irrigation depends on the arterial flow (neoangiogenesis). This is something that helps in their diagnosis (Radiology 1991; 178: 493-497).
The time for an HCC to double its size is about 112 days (Hepatogastroenterology 1993; 40: 311-315). It may occur soonr (<40 days) or much later (400 days). All these can make us understand why the difficulty of making an early diagnosis, specially in cirrhotic livers, and liver with an important amount of preserved architecture.
Imaging Studies
Ultrasound
Minimally invasive technique, with a low cost and common use. Has been used for more that 2 decades in the diagnosis of HCC. Small HCC’s are frequently hyperechogenic. But they may be hypo or isoechogenic.
Sometimes they may be surrounded by an hypoechogenic halo corresponding to the pseudocapsule, or may be heterogeneous with hypo or hyperechogenic zones inside the tumor. This characteristics are more frequently found in HCC, but are difficult to see in small nodules. Multiple studies have proposed the bi-annual follow-up with AFP dosages (J Hepatol 1994; 21: 1029-1034; J Hepatol 1994; 20: 65-71; Cancer 1996; 78: 977-985). These studies showed the success of this starategy.
CT scanning
One of the main characteristics of HCC’s is their almost exclusive arterial vascularization. After the contrast injection, during the arterial phase, hypervascular tumors can be easily viewed, when compared to the normal liver, which has mainly portal vascularization.
Hypervascular tumor apear hyperdense during the arterial phase, but in the mixed phase, they become isodense. The typical semiology of a small HCC is that of a small nodule, usually < 3 cm in diameter, visible only during the arterial phase (Radiology 1996; 199: 505-511). There are certain cases, hemochromatosis for example, when these nodules can be hypodense, but the density of the liver parenchyma is augmented.
The sensibility and specificity of this method for tumors 1-2 cm reaches 43%. But it can make the diagnosis of lesions as small as 1 cm.
Magnetic Resonance Imaging
The major interest in this method is due to its contrast potential, and the possibility of dynamic testing that can be repeated continually. The differential diagnosis between a regeneration nodule and a small HCC is difficult, specially in those cases with hyperintense nodules on T1 and not visible on T2. In these cases, a CT scan is recommended.
Follow-up of Patients with Liver Cirrhosis
To impact survival of HCC, one must fight for early diagnosis. This leads to high costs regarding patient management. This follow-up is helpful in patients with small HCC, Child A and some Child B cases, specially hemochromatosis, or patients who may undergo liver transplantation.
An augmentation of the AFP level is an indication for close follow-up. The usual follow-up consists of US and AFP levels every 6 months. We must remember that the size may double in the majority of cases in 4 months, so the follow-up can be performed every 4 months rather than every 6 months.
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