HCC, or HepatoCellular Carcinoma, is a type of cancer that begins in the liver. People with terminal scarring of their livers (cirrhosis), regardless of the original cause, are at higher risk of developing HCC. People infected with Hepatitis B or Hepatitis C viruses have an even higher risk. Although the presence of active cancer usually precludes the possibility of undergoing a transplant (because the immune suppressing drugs given afterwards can cause a cancer to grow uncontrollably), HCC can potentially be cured with liver transplant, and this is commonly practiced.
There are defined criteria that must be met in order to be considered a good candidate for liver transplant for HCC. These are referred to as the “Milan Criteria” and basically it comes down to if the tumor or tumors are not too large or numerous and they haven’t spread outside of the liver or into the blood vessels of the liver, then transplant is the best option for achieving a complete cure. Specifically, if there is one tumor, it can’t be greater than 5 centimeters (2 inches), and if there are multiple tumors, they can number no more than 3 and each has to be between 2 and 3 centimeters (1 ¼ inch).
When people are placed on the waiting list for liver transplant, where you are on the list depends on how sick your liver is. We estimate the function of your liver by calculating your MELD score (Model for End Stage Liver Disease). This score is obtained by a simple blood test in which the bilirubin (the yellow pigment that causes jaundice), the creatinine (a measure of your kidney function), and INR (a measure of how thin your blood is) values are used in a mathematical formula that generates a number between 6 (perfectly normal) and 40 (critically ill). The higher your MELD score, the sicker your liver, and the higher you are on the list.
This allocation system puts people with HCC at a disadvantage because the liver function is often nearly normal when an early HCC is first diagnosed. If a patient had to wait until their MELD score progressed to within the range of receiving organ offers (here in New York State, MELD scores need to be close to 30 or above to receive an offer), the HCC may grow or spread while waiting. The United Network of Organ Sharing (UNOS, the national oversight agency for transplantation in the U.S.) allows “exception” MELD points to patients with HCC who are within the Milan Criteria. Upon being placed on the waiting list, the MELD score automatically starts at 22 and every 3 months, if still within criteria, an additional 2 points are added. Most HCC patients undergoing transplant have “exception” MELD scores of around 30, but their true (or “biologic”) MELD scores are much lower. That means that most HCC patients are not terribly sick or may even feel completely healthy at the time of their transplant.
HCC is almost always diagnosed with a CAT scan or MRI. These imaging studies demonstrate tell-tale characteristics that usually make biopsy of the tumor unnecessary. If there is any doubt, then biopsy will be performed, but this is rare. We often proceed to treatment based solely on imaging studies and other clinical information alone. A blood test called “AFP” (Alpha FetoProtein) is always checked, as it can be elevated in up to 60% of patients with HCC, but it can be normal despite the presence of tumor. Also, the AFP level doesn’t necessarily correlate with how extensive the tumor is, but steadily increasing levels or extremely high levels do raise concern for a more advanced or aggressive tumor.
Once the diagnosis of HCC is made and the patient is deemed to be a good candidate for transplant, the patient is immediately put on the list with exception points and offered treatment to slow down or halt the growth of the tumor while waiting for the MELD points to accrue (this can take between 9 and 15 months in New York State). If the patient is not a good candidate for transplant because of medical, surgical, or social reasons, HCC treatment will still be offered. If the HCC is discovered too late and the tumor has already spread outside of the liver or into the liver blood vessels, then palliative care or comfort care approaches are considered. Finally, if the HCC is slightly outside of the Milan criteria (for example, 4 tumors instead of 3, or a single tumor measuring 5.5 centimeters), then the possibility exists to try to “downsize” the tumor to get the patient within Milan Criteria so that they can be transplanted.
Two basic approaches to HCC tumor control exist: catheter based “embolization” therapies and directed needle “ablation” therapies. For embolizations, a catheter is placed in the groin and directed into the liver where chemotherapy (“TACE” or TransArterial ChemoEmbolization) or radiation coated glass beads are injected directly into the tumor. Large portions of the liver can be treated at one time with these methods. Tumor ablations are usually performed by placing needles through the skin directly into the tumor to deliver energy (most often radiofrequency waves) that kills the tumor. This is known as “RFA” or RadioFrequency Ablation. These procedures are most always performed by the Interventional Radiologists using conscious sedation and do not require admission to the hospital afterwards. These two approaches are very effective in keeping the HCC in check prior to transplant, but they are not considered curative therapies.
Liver cancer can also be surgically removed. Although the results can be quite good, the recurrence rates can be as high as 50% or greater within 5 years of surgery. With liver transplantation for HCC, survival rates are greater than 80% at 5 years and the recurrence rate is 12% or less at 5 years. These excellent results are achieved because not only is the tumor taken out at the time of transplant, but also the diseased liver that is predisposed to forming tumors. Sometimes surgical removal (or “resection”) is considered if the patient is not a good transplant candidate or, rarely, in order to improve one’s chances for ultimately getting a liver transplant. But the most common course of action, if possible, is to list for transplant, apply for exception points if within the Milan Criteria, and to begin tumor embolization and/or ablation treatment as soon as possible to stay within criteria or to attempt “downsizing” if slightly outside of criteria.
As you can see, treatment decision pathways for HCC are complicated and can vary greatly depending on the individual’s clinical situation. Nonetheless, excellent results can be achieved if the HCC is caught early. Our multidisciplinary approach to HCC and transplant here at the University of Rochester Medical Center involves surgeons, hepatologists, oncologists, interventional radiologists, imaging scientists, pathologists, and nurse coordinators, all of the highest order, working together to deliver state of the art and highly personalized care.