Advanced Precision in a Community-Based Setting: Leveraging Imaging to Improve Patient Outcomes

IO LEARNING 2022(10):E30-E35. Epub 2022 August 26.

Interview

Tell us about your Interventional Oncology practice at St Joseph’s Medical Center.

My interventional oncology practice has greatly evolved over the last 5 years. Early on in my career, we were doing very few interventional oncology cases at our hospital, mostly in the salvage setting. This amounted to about 5 transarterial chemoembolizations (TACEs) per year, all on patients who were advanced stage, and as a result, our outcomes were very lackluster. Over the years, however, we have become one of the busier community-based interventional oncology (IO) practices in the country, performing over 120 Y90 treatments per year for both primary and metastatic disease.

How did you build your practice and gain referrals?

When I first thought about trying to build an IO practice, I started thinking about ideas on how to do so. I started attending our multidisciplinary tumor board regularly. Tumor boards are an absolute must for anyone thinking about starting or building an IO program. At tumor board, I introduced new concepts and approaches to my organization’s referring physicians which included Liver Reporting & Data System (LI-RADS) as well as radiation segmentectomy and lobectomy. As new data on liver-directed therapy became available, we would discuss it at tumor board and whether it was right for our patients. I spent time discussing and educating the community on key differences between locoregional therapy (LRT) options.

I also had several conversations with surgeons and got them on board as collaborative partners.

I held educational lunch and learns with referring physicians and discussed all LRT treatment options as well as when surgery or transplant are indicated. I invited guest speakers like Sid Padia, MD (UCLA) to our tumor board to present on his experience with Y90 and the success of his IO practice. Then, once I performed a substantial number of cases, I presented those results at our tumor board, which was incredibly impactful to my peers from referring departments. Lastly, I created a monthly multidisciplinary tumor board dedicated to hepatocellular carcinoma (HCC) in conjunction with University of California San Francisco Transplant Hepatology team to discuss cases from across our local/regional community. This allowed for collaboration on best practices for this clinical specialty.

Are there any specific challenges you face in a community hospital? How does this differ from academia?

In the community setting, many referring physicians may not believe in LRT. Or if they do, they may not know when it is indicated or the key differences between Y90, TACE, and ablation. Referring physicians may not be up to date on recent literature. There is also a lack of dedicated HCC tumor boards in community hospitals, which lends to lack of awareness around options and has inhibited multidisciplinary collaboration. The referral process with medical oncology, gastrointestinal, and primary care teams managing patients is not straightforward. Any or all of these specialties can refer patients to local transplant centers even when they themselves are not usually associated with the transplant center, so keeping patients in the community for management and treatment may be a challenge

Tell us about the clinical presentation of patients with hepatocellular carcinoma and your clinical approach.

When I see a new HCC patient, the first question I ask myself is whether we are trying to achieve curative or palliative intent. This is based upon tumor burden, functional status, and stage. Depending upon stage of disease, we then discuss all potential treatment options with the patient. If we decide to move forward with Y90, we then create a personalized dosing strategy specific for the patient. If patients are BCLC 0 or A, our dosing strategy includes ablative personalized dosimetry, with a minimum of 500 Gy delivered to perfused liver volume, ensuring tumoricidal dosing. In the case of intermediate and certain patients with advanced stage disease, I look at whether there is a chance to downstage these patients to surgical resection or transplant, and if so, we will tailor a very specific dosing regimen for them. In the case of very large tumors, we may treat different tumor feeding vessels in a staged sequential fashion, using a partitioned approach to really maximize tumor necrosis. In the case of tumors with branch portal vein invasion, we will treat all tumor-feeding vessels, including those supplying the tumor thrombus, with ablative dosing. We work very closely with our surgeons and in conjunction with our regional transplant centers to provide a multidisciplinary approach.

What makes these procedures so challenging?

The most important factors during the mapping procedure are to evaluate flow dynamics, identify all feeder vessels supplying the tumor, and look for any potential for nontarget embolization risks. If we are planning for selective treatments for durable long-term response, identifying all vessels feeding the tumor is critical to ensure we are treating the entire tumor.

How does the imaging impact your ability to treat HCC?

Prior to treatment, we perform preprocedural imaging, which includes magnetic resonance imaging, to determine extent of disease. When we perform mapping angiography, we always perform intraprocedural cone-beam CT (CBCT) to restage patients, as well as determine the volume of liver that needs to be treated. This is most often done from the proximal right and left hepatic arteries. This provides us with the most accurate volume measurements and is also effective for helping identify the tumor-feeding vessels. We routinely utilize syngo Embolization Guidance (Siemens Healthineers, Forchheim, Germany) in cases when multiple tumor feeding vessels are suspected/identified to aid in vessel selection.

What impact does navigational software like syngo Embolization Guidance have on your cases?

Embolization Guidance allows us to identify all tumor-feeding vessels, including smaller ones that we may not readily appreciate or see during routine angiography. Not only does the software identify feeding vessels, it also helps me determine the exact injection site for dose delivery. This ensures I am effectively covering the tumor with adequate margins and treating all vessels supplying the tumor. Siemens Embolization Guidance has impacted my practice greatly and increases my clinical confidence.

Does the navigational software like syngo Embolization Guidance impact the patient?

During any given case, we are using very little contrast and have been able to effectively decrease dose to the patient with our workflow on Siemens Healthineers technology. This includes performing CBCT from a proximal location to the tumor and utilizing syngo Embolization Guidance to identify the tumor-feeding vessels. This workflow prevents us from performing multiple DSA acquisitions throughout the procedure. We use the 3D overlay to follow the course into those vessels, and then inject our Y90 dose.

In a community hospital-based setting there can be budget constraints that may deter organizations from purchasing advanced navigational software. Any advice for other healthcare providers on how to gain administration’s buy-in for these advanced features?

The added value of syngo Embolization Guidance allows interventional radiologists to get more selective during Y90 treatments thereby yielding better results. Because we are able to achieve improved clinical outcomes, we in turn get more referrals from other providers for additional cases. DynaCT has become the standard of care for intra-arterial therapy. It allows for intraprocedural mapping and precise measuring of the volume needed for embolization, which allows for more accurate dose calculation. DynaCT and syngo Embolization Guidance also help me quickly identify the feeder vessels, subsequently saving me a lot of time and allowing for quicker room turnover. Furthermore, it allows for lower contrast utilization and radiation dose to the patient, operator, and staff in the procedure. These advanced features support me and the institution to achieve better patient outcomes and an increased patient satisfaction. Both aspects are key differentiators in today’s competitive landscape.

Case Presentation

A 63-year-old female with a history of nonalcoholic steatohepatitis (NASH) cirrhosis presented at our hospital for routine hepatocellular carcinoma (HCC) screening. Her laboratory results showed an alpha-fetoprotein (AFP) of 2462 ng/mL, total bilirubin of 0.7 mg/dL, platelet count of 156 g/L, albumin of 3.6 g/dL, and international normalized ratio of 1.

A diagnostic computed tomography (CT) scan was acquired to determine the progress of HCC. A multiphase axial CT of the abdomen was ordered and the image findings demonstrated a 2.1-cm, arterially enhancing lesion in segment 2, with washout on delayed imaging (LR5). Axial and coronal images of the lesion are demonstrated in Figure 1 and Figure 2, respectively.

The patient was discussed during a multidisciplinary HCC tumor board to evaluate treatment options. Due to a markedly high AFP, the decision was made to proceed with locoregional therapy, specifically with Therasphere Y-90 glass microspheres (Boston Scientific), and to evaluate tumor biology. Following this, if patient responded well to Y-90, the next step would be to list the patient for liver transplant.

The patient underwent a mapping hepatic angiogram prior to treatment. The mapping procedure is used to delineate the hepatic arterial anatomy, which is important for eventual dose delivery, and to avoid nontarget delivery to healthy tissue and other organs. In this patient, the mapping demonstrated replaced left hepatic artery arising from the left gastric artery (Figure 3).

Segment 2 hepatic arteriogram (Figure 4) was performed with cone-beam CT (syngo DynaCT, Siemens Healthineers, Forchheim, Germany). The angiographic images demonstrated tumor blush, as expected from preprocedural multiphase CT imaging. However, performing cone-beam CT is crucial during selective treatments to ensure adequate coverage of vascular supply to the tumor. In this case, cone-beam CT images demonstrated only partial opacification of the tumor. There was a portion of the tumor, however, that was nonenhancing on the images, suggesting a different additional tumor feeding vessel.   

Due to the location of the tumor in the left lobe, an additional suspected tumor feeding artery was likely in segment 4. Therefore, segment 4 hepatic artery was selected, and arteriogram was performed with cone-beam CT (Figure 5). This demonstrated tumor vascularity in the left hepatic lobe in the presumed location of the tumor. Cone-beam CT images confirmed arterial enhancement of the portion of the tumor not supplied by the segment 2 hepatic arterial branches.

The syngo Embolization Guidance feature (Siemens Healthineers) was utilized to identify which branch of the segment 4 artery was supplying this portion of the tumor, as we believe in superselective treatments to maximize dose to the tumor. Embolization guidance demonstrated 2 separate tumor-feeding vessels supplying the tumor. Additional cone-beam CT images demonstrated a falciform artery distally arising from segment 4 hepatic artery (Figure 6).

Coil embolization of the falciform artery was performed utilizing 2-mm soft IDE interlock coils (Boston Scientific). Following this, the microcatheter

was advanced slightly more distally, and cone-beam CT imaging was performed, demonstrating tumor vascularity (Figure 7).

Ablative dosing with Therasphere Y-90 glass microspheres (Boston Scientific) was then performed. A dose of 962 Gy was delivered to the perfused liver volume (Figure 8).

Axial CT images (arterial and delayed phase imaging) as well as coronal CT images were performed 6 months following the procedure (Figure 9). These scans demonstrated complete response within the treatment cavity, without evidence of residual or recurrent enhanacement (LR-TR nonviable). The AFP at this time was 6 ng/mL.

From Dignity Health, St Joseph’s Medical Center, Stockton, California.

Disclaimer: The statements by the Siemens Healthineers’ customer herein are based on results that were achieved in the customer’s unique setting. Since there is no “typical” hospital and many variables exist (eg, hospital size, case mix, level of IT adoption) there can be no guarantee that other customers will achieve the same results.

Address for correspondence: Pavan Khanna, MD, MS, Advanced Radiology and Interventional Associates (ARIA), St Joseph’s Medical Center, 1800 N California St, Stockton, CA 95204. Email: pavan.khanna@gmail.com