SEMC RADIOLOGY 12/15/2014 Edition 3, Volume 1 UPDATE

INTERVENTIONAL ONCOLOGY

Interventional Radiology at SEMC is able to radiation up to 40 times higher than conventional perform the full range of IR procedures for radiotherapy, while sparing healthy tissue. oncology patients from and port placement to preoperative arterial embolization. SIR-Spheres microspheres are FDA approved for The SEMC radiology department is also treatment of unresectable metastatic that has spread to the . Ongoing research dedicated to partnering with you to provide and peer reviewed published papers in the literature comprehensive minimally invasive treatment of suggest that yttrium-90 microspheres are also primary and metastatic cancer of the liver, lung effective in treating other forms of primary liver and and using the latest technology and metastatic . These include hepatocellular techniques. Two of these cutting edge carcinoma as well as liver metastases from other techniques are Y90 radioembolization for primary sources, such as neuroendocrine tumors. metastatic or primary liver disease and percutaneous microwave ablation. Treatment is accomplished on an outpatient basis under conscious sedation. The treatment consists of a mapping angiogram (Figure 1) to reduce the risk of nontarget embolization, calculation of the Y90 Radioembolization appropriate dose based on liver and tumor volumes, followed by radioembolization. Right and left lobes The radiology and nuclear medicine department at of the liver are treated separately to reduce the risk SEMC are able to offer radioactive microsphere of acute liver injury. embolization with SIR-Spheres, the only FDA- approved microspheres for metastatic .

At least 60 percent of the nearly 150,000 Americans diagnosed with colorectal cancer every year will have metastases to the liver, and most of these patients are not candidates for surgical resection. Liver failure is the leading cause of mortality in these patients. Radioactive microsphere therapy has emerged as a well tolerated treatment option for patients with metastatic colorectal cancer who are not candidates for surgical resection or percutaneous ablation.

SIR-Spheres microspheres are microscopic resin spheres (average size 32 microns) that can be delivered by the millions directly to a liver lesion. The microspheres contain the radioactive isotope yttrium-90, which selectively delivers beta radiation Figure 1: Mapping angiogram demonstrates multiple to the tumor while minimizing radiation exposure to hypervascular lesions throughtout the liver prior to normal liver parenchyma. The microspheres radioembolization. selectively target liver tumors with a dose of internal SIR-Spheres radioembolization is extremely well tolerated with the most common post-procedure complaint being fatigue. Common side effects from traditional chemoembolization, such as post- embolization syndrome, nausea/ vomiting, and right upper quadrant pain are rare with Y90 radioembolization. Nontarget embolization is also extremely rare using current techniques and microcatheters; cholecystitis, gastritis, or duodenitis have been reported.

Clinical studies have shown SIRT with SIR-Spheres microspheres increases the time-to-disease progression and overall survival without adversely affecting the patient’s quality of life. In clinical studies, SIR-Spheres microspheres have been combined with modern (FOLFOX or FOLFIRI) or administered as a monotherapy during a chemotherapy holiday. The most promising results utilize SIR-Spheres radioembolization as a first line therapy.

SIR-Spheres microspheres have been proven to provide an overall survival advantage to chemotherapy refractive patients and increase response rates consistently across lines of therapy. The ideal SIR-Spheres patient has non-resectable disease, liver only or liver dominant , good performance status, adequate liver function, expected survival greater than 3 months, and less than 2 mg/dl.

There is widespread insurance coverage for metastatic colorectal carcinoma, however, preauthorization usually must be obtained on a case by case basis.

Percutaneous Microwave Ablation

NCCN guidelines state that ablative techniques may be considered alone or in conjunction with surgical resection. Depending on the type of cancer, anywhere from 20-40% of patients are not candidates for surgery. There are other patients who are personally averse to surgical options for whom Figure 2: Top image demonstrates a liver metastasis microwave ablation may be a useful treatment. adjacent to the IVC. The middle image shows placement of two microwave probes. The final image Ablation is also a valuable adjunct to systemic is a 1 month follow up showing successful ablation. therapies and can be offered to patients without interrupting primary chemotherapy or radiation and Percutaneous (RFA) was can be used to contain disease progression when previously the primary technology used for ablation. systemic treatment is poorly tolerated. However, limitations of RFA are a consequence of the technology which uses passive heating of tissues with There is widespread insurance coverage for electrical current. Single probe systems requiring percutaneous ablation with microwave based on data multiple overlapping ablations and poor performance supporting RFA, however, preauthorization may be near vascular structures led to the development of necessary. alternative ablative technology.

Microwave ablation uses the rapid oscillation of water molecules to primarily heat tissue. This provides for faster heating, and larger, predictable ablation zones with higher temperature. Microwave ablation is also effective in low conductivity tissue such as lung and bone.

Consequently, microwave ablation has become the mainstay of percutaneous ablation in the liver, lung, bone, and in some cases kidney.

The procedure is performed under general anesthesia and is accomplished with image guided placement of the microwave probes, usually using a combination of ultrasound and CT guidance (Figures 2 and 3). Ablation is then performed.

Percutaneous ablation in the liver is extremely well tolerated with a low incidence of complications. The literature demonstrates improved overall survival with a low incidence of local recurrence in both primary and metastatic liver disease. Studies are also ongoing combining ablation with transarterial therapy in the liver and systemic chemotherapy.

Published literature regarding microwave ablation in the lung and kidney consists of small studies, but clinical trials are ongoing. Data is also now emerging regarding microwave ablation verses SBRT in the lung. Initial studies show comparable if not improved survival with decreased overall cost of treatment.

Figure 3: Top image demonstrates placement of a Ideal patients have solitary metastatic or primary disease, whether it be in the liver or lung. Many single microwave probe in a solitary lung mass. The factors affect clinical decision making for these second image immediately post ablation shows patients, including the anatomic location and number successful ablation with an adequate margin. of the lesions being considered for ablation. Ideal patients have solitary metastatic or primary disease and are not candidates for surgical resection. Dr. Sequeira is available for discussion of these However, patients with two or even three lesions treatment options and can be reached at may undergo successful ablation as definitive local [email protected] or by pager for image therapy. The latest generation of microwave ablation review prior to a formal consult. Patient technology which is now available at SEMC allows for consultations can be arranged through Linda Keener highly customized ablation tailored to the patient’s at 617-789-2740. disease, while at the same time using the smallest microwave probes available today to make the procedure as minimally invasive as possible.