What is Fibrolamellar Hepatocellular Carcinoma?
Fibrolamellar hepatocellular carcinoma (FL-HCC) is a rare type of liver cancer that behaves differently and has different clinical symptoms compared to the more common hepatocellular carcinoma (HCC). FL-HCC accounts for only about 1% of all primary liver cancers. The people affected by FL-HCC are usually younger than those with HCC. The symptoms, blood tests, imaging tests, and treatment plans for FL-HCC are different from those for HCC. It’s crucial to promptly diagnose FL-HCC and start the right treatment plan as it can impact the patient’s outcome. This passage is aimed at shedding light on the main features of FL-HCC and how it contrasts with HCC.
What Causes Fibrolamellar Hepatocellular Carcinoma?
The cause of a specific kind of liver cancer called FL-HCC isn’t always easy to identify. Patients with this type of cancer typically don’t have a history of other long-term liver diseases, like cirrhosis. Interestingly, less than 10% of patients diagnosed with FL-HCC have a liver appearance that resembles cirrhosis. This is quite different from patients diagnosed with a more common type of liver cancer (HCC), who often show signs of cirrhosis or liver fibrosis, a condition where the liver becomes excessively scarred.
Risk Factors and Frequency for Fibrolamellar Hepatocellular Carcinoma
Fibrolamellar Hepatocellular Carcinoma (FL-HCC) usually affects people in their 20s and 30s, whereas Hepatocellular Carcinoma (HCC) often strikes older people, typically around their 60s. FL-HCC accounts for only 1% of liver cancer cases, so it’s rare. HCC is more common in men, but FL-HCC doesn’t have a gender preference – it can affect anyone. More than half of those who have FL-HCC are white, and this is also true for over 80% of HCC cases.
- People in their 20s and 30s are more likely to be affected by FL-HCC.
- HCC, on the other hand, usually affects people in their 60s.
- FL-HCC accounts for a small fraction of liver cancer diagnoses (1%).
- Men are more likely to get HCC, but FL-HCC affects both genders equally.
- A majority of people with FL-HCC are white, as are over 80% of those with HCC.
Signs and Symptoms of Fibrolamellar Hepatocellular Carcinoma
Patients often come to the hospital with symptoms that could make someone think they have a liver tumour. These symptoms could vary from general pain to noticing a lump while getting themselves checked for some other condition. The most common symptoms that these people notice are abdominal pain or a tangible lump. They usually won’t show any symptoms that are common in serious liver cancer. Blood tests for liver cancer are not typically useful in diagnosing this and only less than 10% of the people have higher than normal values.
Testing for Fibrolamellar Hepatocellular Carcinoma
When a doctor is checking for possible liver conditions, they often use imaging techniques to see what’s happening inside the body. The most commonly used methods are ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI).
In an ultrasound, the liver might appear as a lump with a texture that varies. However, these images can be quite vague and may not conclusively distinguish liver conditions from one another. If there’s a central scar – a common feature of some liver conditions – it might show up on the ultrasound as a brighter area, but it’s not always easy to spot.
A CT scan, on the other hand, usually reveals a single, clearly bordered tumor. Most of these kinds of tumors appear less dense on a CT scan. Over 70% of patients show a calcified central scar. To get the most detailed images, doctors usually inject patients with a contrast agent and take several scans at different time points. This helps to highlight the different features of the liver during the arterial, portal venous, and delayed phases. Over 80% of patients show masses that are more responsive to the contrast agent in the arterial phase, which reflects the high blood supply of these tumors. Almost half of these masses look similar to the background liver in the venous phase, and about one-third of the tumors show higher responsiveness to the contrast agent. During the later phase, almost two-thirds of these masses look similar to the background liver, and can be difficult to differentiate. The central fibrous scar in these masses can react to the contrast agent in this later phase.
MRI shows a decreased signal on T1-weighted sequences in about two-thirds of the patients. The scar, due to its fibrous nature, often shows decreased signals on both T1 and T2 weighted sequences. The enhancement characteristics of the tumor and the central scar are similar to those seen on CT imaging. Like many other malignant tumors, these can also show restricted diffusion with an increased signal on sequences where diffusion is being weighed (DWI). An additional benefit of using radiological evaluations is that they can help detect any diseases located elsewhere in the body that may not otherwise be apparent.
Treatment Options for Fibrolamellar Hepatocellular Carcinoma
The primary treatment for this type of tumor involves following a plan that aims to completely cure the condition. Where possible, complete removal of the tumor is the preferred treatment and it seems to provide better results. However, it’s important to note that a high percentage of patients (more than two-thirds) eventually experience a recurrence of the disease. During the surgical treatment, a fair number of these patients are found to have additional sites of disease. These additional disease sites are also treated alongside the primary tumor removal, which has been shown to have a better prognostic value. These tumors often grow aggressively which sometimes leads to unsuccessful surgeries, need for second surgeries, or even liver transplants.
Chemotherapy, which is the use of drugs to destroy cancer cells, has been used as a treatment before and after surgical removal of the tumor. However, due to the rarity of this type of tumor, no Randomized Controlled Trials (RCTs) have been conducted to determine the most effective chemotherapy regimen. Chemotherapy drugs such as gemcitabine, cisplatin, 5-fluorouracil, interferon, and oxaliplatin have been used and have shown varying results. Treatment plans that combine surgery, chemotherapy, and radiation have displayed better results. There have been studies into reducing the size of the tumor before surgery using a method called percutaneous radioembolization.
There’s a promising new targeted therapy using a drug called sorafenib, which has been found to be effective in treating this type of tumor. However, its effectiveness is limited. Other potential targets in the process of tumor formation and growth have recently been identified. Currently, no controlled trials have evaluated these targets. There’s been a positive outcome in using a drug called rapamycin on a patient who couldn’t have surgery. Checkpoint inhibitors, a type of cancer treatment that helps the immune system to recognize and attack cancer cells, have also shown promising results in a phase II study. However, controlled trials evaluating checkpoint inhibitors in this type of tumor are still lacking, and the case reports available so far are limited and unequivocal.
What else can Fibrolamellar Hepatocellular Carcinoma be?
There are several conditions that share symptoms with this disease, including:
- Focal nodular hyperplasia
- Giant cavernous hemangioma
- Hepatocellular carcinoma (HCC)
Medical imaging helps to differentiate these conditions from each other.
In terms of Focal nodular hyperplasia, it tends to show the normal liver tissue characteristics during specific phases of imaging. During the early phase, it may appear overly bright. A common aspect of the disease is that it does not commonly result in calcium build-up. It usually presents as an intense signal in the middle of the scar tissue common in such masses, which is due to the biliary ductules, not caused by the scar related to FL-HCC.
Giant cavernous hemangiomas display enhancement characteristics of blood vessels under all three imaging phases. The typical pattern observed is inconsistent and nodular enhancement on the edges of these masses in the early stages, with following contrast filling the center of the mass.
Finally, Hepatocellular carcinoma (HCC) is often observed with a bright enhancement in the early phase and fades away during the delay phases. Patients with this condition usually have a cirrhotic or severely scarred liver, which can be spotted in the imaging.
What to expect with Fibrolamellar Hepatocellular Carcinoma
Successful surgery generally results in better outcomes overall. However, if the disease has spread in the region or to distant parts of the body, it can negatively impact the overall results. As one might expect, survival rates tend to decrease as the disease spreads to more areas within the body.
A rarity indeed, but if patients show signs of conventional Hepatocellular Carcinoma (HCC), which is liver cancer, in addition to Fibrolamellar HCC (FL-HCC), a rare type of liver cancer, it can have a negative effect on their prognosis. However, if you compare patients who have cirrhosis, a chronic liver disease, to those with a healthy liver, those with FL-HCC surprisingly fare better than those with traditional HCC.
Statistically, people diagnosed with FL-HCC have a significantly better chance of survival than those with conventional HCC. Factors that are associated with improved outcomes include having the disease restricted to the liver, successful removal of the tumor during surgery, and the use of various treatment methods as previously detailed.
Possible Complications When Diagnosed with Fibrolamellar Hepatocellular Carcinoma
People who need complicated surgery often experience various challenges, particularly if they are younger and dealing with more severe liver diseases. Given the seriousness of these conditions, a more aggressive treatment approach is typically required, which can lead to a higher rate of surgical complications.
Common Complications:
- Significantly increased surgical complications
- More severe liver diseases
- Complex and aggressive treatment approaches
Preventing Fibrolamellar Hepatocellular Carcinoma
It’s important to educate patients about the risks associated with this disease because there’s a high chance of the disease coming back.