Hepatitis B Virus Screening and Management for Patients with Cancer Prior to Therapy Provisional Clinical Opinion Update

An interview with Dr. Jessica Hwang from MD Anderson Cancer Center and Dr. Andrew Artz from City of Hope Cancer Center on "Hepatitis B Virus Screening and Management for Patients with Cancer Prior to Therapy: ASCO Provisional Clinical Opinion Update." This update presents a clinically pragmatic approach to HBV screening and management that calls for universal HBV serological testing of patients at the onset of anticancer therapy. Read the full PCO at www.asco.org/supportive-care-guidelines

Transcript

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Hello, and welcome to the ASCO Guidelines podcast series brought to you by the ASCO Podcast Network a collection of nine programs, covering a range of educational and scientific content and offering enriching insight into the world of cancer care. You can find all the shows including this one at podcast.asco.org.

My name is Brittany Harvey. And today, I'm interviewing Dr. Jessica Hwang from the University of Texas M.D. Anderson Cancer Center in Houston, Texas, and Dr. Andrew Artz from the City of Hope Comprehensive Cancer Center in Duarte, California, co-chairs on hepatitis B screening and management for patients with cancer prior to therapy, ASCO provisional clinical opinion update. Thank you for being here, Dr. Hwang and Dr. Artz.

Thank you for inviting us.

Thank you so much.

First, I'd like to note that ASCO takes great care in the development of its guideline products and ensuring that the ASCO conflict of interest policy is followed. The full conflict of interest information for this provisional clinical opinion panel is available online with the publication in the Journal of Clinical Oncology. Dr. Hwang, do you have any relevant disclosures that are related to this topic?

Well, I have received some research funding from Gilead, a maker of a hepatitis drug in the past.

And, Dr. Artz, do you have any relevant disclosures?

I have no relevant disclosures.

OK, then so, Dr. Artz, so this provisional clinical opinion, or PCO, on hepatitis B screening and management for patients with cancer prior to therapy was first published in 2010 and then last updated in 2015. What prompted this update to the PCO?

This PCO guidance, more broadly, is necessary because the hepatitis B status for most patients is actually unknown at the time they're starting cancer therapy. In 2015, the PCO though suggested that we limit hepatitis B screening to patients who were at most risk for hepatitis B reactivation, if they were hepatitis B carriers, so those receiving anti-CD20 antibodies, such as rituximab or stem cell transplant. But for the remaining patients, most patients receiving cancer therapy, the guidance was to survey patients about their close contacts or exposures to hepatitis B and determine if formal hepatitis testing should ensue.

This 2020 PCO represents an evolution in our understanding of hepatitis B screening and the dangers of hepatitis B after anticancer therapy. We've learned from studies, including those done by my colleague, Dr. Hwang, that questionnaires to detect hepatitis B are not very effective or practical. We also have accumulating information that many of our anticancer therapies pose a significant danger for hepatitis B related complications in hepatitis B infected patients. We believe appropriate monitoring and treatment, as outlined in the PCO, will reduce these dangers.

So given that new information, I'd like to discuss the updated statements for the PCO. So first, Dr. Hwang, for patients who will receive systemic anticancer therapy, who should be tested for HBV and how should they be tested?

That's a great question, Brittany. Thanks. I think that the data is really clear now that all patients with cancer anticipating systemic anticancer therapy should be tested for hepatitis B virus. That includes all solid tumor patients, as well as hematologic malignancy patients.

And they can be tested with a simple blood test. The hepatitis B virus can be tested by three blood tests for hepatitis. It's the hepatitis B surface antigen, HBsAG, or the hepatitis B core antibody. There are two types of this. It's either the IgG or the total IG, which shows, if positive, could indicate a patient has past infection. There is a IgM version of that core antibody test. And that tells, if positive, tells whether a patient has acute infection. So for our purposes, it's recommended that the IgG or total IG is used and not the IgM, because we are interested in whether a patient has past infection.

So the third test is a hepatitis B surface antibody. And this is a protective antibody. So if positive, it shows that a patient has had some exposure in the past or perhaps a vaccination in the past. And so this is a good test to have positive.

So then what does the PCO state for patients with chronic HBV infection?

Patients with chronic HBV infection, that is those patients with a positive hepatitis B surface antigen test, these patients really should have very close monitoring during as well as after anticancer therapy. These patients will need antiviral therapy prophylactically prior to enduring as well as after the cancer treatment. They should also see a clinician experienced in the management of hepatitis B, whether it's a hepatologist, a gastroenterologist, an infectious disease specialist, or maybe a primary care doctor who's experienced in treating and caring and monitoring for patients with hepatitis B. That's really important for these patients with a chronic hepatitis B, because they are at high risk of developing complications during and as well as perhaps even shortly thereafter of receiving systemic anticancer therapy.

And then what does the PCO state for patients with past HBV infection?

This is a really good question. The patients with past HBV infection are those who have a negative hepatitis B surface antigen and a positive hepatitis B core antibody. This represents maybe some 6% at least of the US population. It could be much higher. So this is a sizable group of patients. And it's really important to know that it is sort of a tailored approach.

So patients with past HBV infection who are anticipated to receive one of the high risk anticancer therapies that Dr. Artz mentioned just a few moments ago, namely stem cell transplantation or maybe one of the anti-CD20 monoclonal antibodies, these patients are at really high risk of reactivation. So these patients would need a very close monitoring plan. They would need their hepatitis B and liver test monitored during their anticancer therapy. And most often they would need antiviral prophylaxis before, during, and even after their immunosuppressive therapy ends.

So there are patients, of course, who don't receive these high-risk therapies. So that is patients with past HBV infection who are receiving anticancer therapy that's not a stem cell transplant and not an anti-CD20 monoclonal antibody. These patients could be monitored carefully. They could have hepatitis B and/or liver testing monitoring during anticancer therapy. And if they have any elevations in their surface antigen or their ALT, then they could have further hepatitis B testing to see if they have any evidence of complications from their hepatitis B. So that's in general what the PCO recommends for these two groups.

Well, thank you for reviewing those highlights from the PCO. So Dr. Artz, what is the importance of this PCO and how will its implementation impact practice?

Thank you for the question. This PCO I feel dramatically simplifies the challenge of hepatitis B screening by proposing universal hepatitis B testing, as Dr. Hwang outlined, at a defined point in time. That is at the initiation of therapy.

And clinicians have really struggled with hepatitis B testing for lots of different reasons. They're difficulties in knowing who to screen, how to screen, in part because the data have started to emerge that many of the therapies may pose some risks and the prior suggestion that we use questionnaires, but there wasn't a standard set of questionnaires that we could use if we wanted to identify people based on risk factors of acquiring hepatitis B. So this led to a lot of confusion on testing.

I think by standardizing this makes it considerably easier. And also, the guidance from the PCO is better harmonized with other organizations, such as the Centers for Disease Control and our Liver Society colleagues who actually participated in the panel. And so now the guidance clinicians receive are more consistent across organizations. So I think this will allow doctors and health care systems overall to now invest in the implementation of hepatitis B screening, rather than the question about who should we do it and can we do it and when should we do it, but rather more on the implementation to help patients.

Great. And then finally, what is the impact of this updated PCO for patients?

Well, I'll take the first part of that. I believe that the implementation should permit safer systemic anticancer therapy by reducing hepatitis B related complications. Whenever patients have complications or there's even uncertainty about whether hepatitis might be contributing, this also can lead to delays in our treatments. If we know in advance and we appropriately manage and monitor this, we should have fewer treatment delays as well. Dr. Hwang, I know, might also have some comments on this.

Thanks. I do have a few general comments beyond the cancer care implications. And I'd like to say I think that hepatitis B testing and then the results of that and sharing that information with patients is really important. Letting patients know their hepatitis B status, especially if they're positive, empowers them to seek further care, get connected with a hepatitis B specialist person who's experienced in managing hepatitis B, and also to look around the local environment to their household and close contacts because hepatitis B is a virus that is transmitted from person to person through blood-borne sexual transmission and close family or household contact.

So I think it's important for patients to know their status to protect themselves during cancer therapy, as Dr. Artz mentioned, but just in general for good health care for themselves and for those around them. And in addition, I think that it's important for the family members and those close contacts to then get screened and perhaps even consider getting vaccinated if they haven't been vaccinated.

Well, thank you both for your hard work on updating this PTO and for taking the time to speak with me today, Dr. Hwang and Dr. Artz.

Thank you, Brittany.

Thank you, Brittany.

And thank you to all of our listeners for tuning into the ASCO Guidelines podcast series. To read the full provisional clinical opinion go to www.asco.org/supportive-care-guidelines. This PCO also has a companion cancer.net podcast episode. Cancer.net is the patient information website of ASCO. And we encourage you to learn more by tuning into their episode. You can find their podcast and all ASCO podcasts at podcast.asco.org.

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