ASCO has updated a provisional clinical opinion recommending that patients with risk factors for hepatitis B virus (HBV) infection or those who will be receiving cancer treatment likely to cause a reactivation of HBV be screened for HBV before beginning cancer treatment. A provisional clinical opinion offers direction to doctors and others who treat people with cancer after the publication or presentation of potentially practice-changing information.
About hepatitis B
HBV is a virus that infects the liver and is detected with a blood test. Long-term infection with HBV damages the liver and can lead to liver cancer, scarring of the liver called cirrhosis, liver failure, and even death. HBV is spread by coming into contact with body fluids, such as blood or semen, of a person who is infected.
HBV infection can be prevented with a three-shot vaccine series. Not all people with HBV infection need treatment for the infection, depending on the results of screening. Some may need regular testing to watch for a reactivation. Others may need treatment with drugs called antiviral medications to avoid reactivation.
Those at high risk for hepatitis B infection include:
- People who use injection drugs
- People with multiple sex partners or those diagnosed with a sexually transmitted disease
- Men who have sex with men
- People who have sexual contact with or live in the same household as someone who is already infected with HBV
- Infants who are born to mothers infected with HBV
- Infants and children of immigrants from areas with high rates of HBV infection, such as Eastern Europe, Asia, Africa, the Middle East, and the Pacific Islands
- Health care workers or other employees who come into contact with human blood
- Patients who are receiving hemodialysis for kidney disease
HBV and cancer
For people with cancer and HBV infection who need cancer treatment that lowers the immune system, there is a risk that an inactive, or latent, infection with hepatitis B can become active again. This is called reactivation, and it could lead to serious liver problems and complicate cancer treatment.
It is not exactly known how a latent HBV infection becomes active or causes problems for people with specific cancers or specific treatments. It is also not clear why some cancer treatments cause reactivation while others do not. Treatments that lower the immune system and have a high chance of leading to reactivation include the following:
- High-dose chemotherapy for a stem cell/bone marrow transplantation
- Treatments that lower the number of B cells, such as anti-CD20 therapy. These include rituximab (Rituxan) and ofatumumab (Azerra), which may be used to treat cancers of the blood, bone marrow, lymph, or lymphatic system.
Recommendations for HBV screening and treatment
In the updated provisional clinical opinion, ASCO recommends the following:
- Right now, there is not enough scientific evidence to recommend screening every patient for HBV.
- Patients should receive HBV screening if they have a high risk of HBV infection or are going to receive a cancer treatment that increases the risk of HBV reactivation. These types of treatments include anti-CD20 therapy or stem cell/bone marrow transplantation.
- Testing should include two tests for HBV. One test looks for the hepatitis B surface antigen (HBsAg). The other test looks for the hepatitis B core antibody (anti-HBc). HBV reactivation can happen if both tests are positive or if only the anti-HBc test is positive.
- For patients who test positive for both HBV tests, antiviral therapy should be given before or along with cancer treatment.
- Those who test positive only for the anti-HBc test can be considered for antiviral therapy or be monitored for reactivation of HBV with blood tests every three months instead of antiviral therapy.
Some cancer centers follow what is called universal HBV screening, which means that all patients are screened for HBV before cancer treatment begins. Currently, there is no strong evidence to support either starting or stopping universal screening. Until more research of this topic is available, HBV screening is recommended at least for patients with HBV risk factors and/or patients who are about to receive a cancer treatment linked with a high risk of HBV reactivation.
What this means for patients
Talk with your doctor about whether you need HBV testing given your health, risk factors for HBV infection, and cancer treatment plan. It is important to tell your health care team if you fit the criteria for a high risk of HBV infection and if you have been diagnosed with HBV in the past. Having an HBV test and receiving antiviral therapy if you test positive can help you avoid HBV reactivation.
Patients who need antiviral medication may need to take it during cancer treatment and for six months to one year after cancer treatment. This additional treatment could add to the overall cost of treatment. In addition, patients receiving antiviral therapy may need to visit a hepatitis specialist. If you have a high risk of HBV and/or are going to receive cancer treatment that could reactivate the virus, talk with your doctor about HBV screening and any concerns you may have about managing your care.