Medical policy: Radiofrequency Ablation of Primary or Metastatic Liver Tumors

Número de política: MP 1.055

Fecha de entrada en vigor: 3/1/2026

Política

Radiofrequency ablation of primary, inoperable (e.g., due to location of lesion[s] and/or comorbid conditions), hepatocellular carcinoma may be considered medically necessary under the following conditions:

• As a primary treatment of hepatocellular carcinoma meeting the Milan criteria (a single tumor of less than or equal to 5 cm or up to 3 nodules less than 3 cm); or
• As a bridge to transplant, where the intent is to prevent further tumor growth and to maintain an individual’s candidacy for liver transplant.

Radiofrequency ablation as a primary treatment of inoperable hepatic metastases may be considered medically necessary under the following conditions:

• Metastases are of colorectal origin and meet the Milan criteria (a single tumor of less than or equal to 5 cm or up to 3 nodules less than 3 cm); or
• Metastases are of neuroendocrine origin and systemic therapy has failed to control symptoms.

Radiofrequency ablation of primary, inoperable, hepatocellular carcinoma is considered investigational under the following conditions:

• When there are more than 3 nodules or when not all sites of tumor foci can be adequately treated.
• When used to downstage (downsize) hepatocellular carcinoma in individuals being considered for liver transplant.

Radiofrequency ablation of primary, operable hepatocellular carcinoma is considered investigational.

Radiofrequency ablation for hepatic metastasis is considered investigational for:

• Hepatic metastases from colorectal cancer or neuroendocrine tumors that do not meet the criteria above; or
• Hepatic metastases from other types of cancer except colorectal cancer or neuroendocrine tumors.

There is insufficient evidence to support a general conclusion concerning the health outcomes or benefits associated with this procedure for the above indications.

Cross-references:

• MP 1.088 Cryosurgical ablation of miscellaneous solid tumors other than liver, prostate, or dermatologic tumors
• MP 1.121 Cryosurgical ablation of primary or metastatic liver tumors
• MP 1.084 Radiofrequency ablation of miscellaneous solid tumors, excluding liver tumors

Variaciones del producto

Esta política solo se aplica a ciertos programas y productos administrados por Capital Blue Cross y está sujeta a variaciones en los beneficios. Consulte la información adicional a continuación.

FEP PPO - Consulte el Manual de Políticas Médicas de FEP.

Descripción/antecedentes

Radiofrequency ablation (RFA) is a procedure in which a probe is inserted into the center of a tumor and heated locally by a high frequency, alternating current that flows from electrodes. The heat treats the tissue adjacent to the probe, resulting in a 3- to 5-cm sphere of dead tissue. The cells killed by RFA are not removed but are gradually replaced by fibrosis and scar tissue. If there is local recurrence, it occurs at the edge and, in some cases, may be retreated. RFA may be performed percutaneously, laparoscopically, or as an open procedure.

Hepatic and neuroendocrine tumors

Hepatic tumors can arise as primary liver cancer (hepatocellular cancer) or by metastasis to the liver from other sites. Local therapy for hepatic metastasis may be indicated when there is no extrahepatic disease, which rarely occurs for patients with primary cancers other than colorectal carcinoma or certain neuroendocrine malignancies.

Neuroendocrine tumors are tumors of cells that possess secretory granules and originate from the neuroectoderm. Neuroendocrine cells have roles both in the endocrine system and in the nervous system. They produce and secrete a variety of regulatory hormones, or neuropeptides, which include neurotransmitters and growth factors. Overproduction of the specific neuropeptides produced by the cancer cells causes various symptoms, depending on the hormone produced. They are rare, with an incidence of 2 to 4 per 100,000 per year.

Tratamiento

Treatment options for hepatocellular carcinoma (HCC) range from potentially curative treatments, such as resection or liver transplantation, to nonsurgical options, which include ablative therapies (radiofrequency ablation [RFA], cryoablation, microwave ablation, percutaneous ethanol, or acetic acid injection), transarterial embolization, radiation therapy, and systemic therapy. Choice of therapy depends on the severity of the underlying liver disease, size and distribution of tumors, vascular supply, and patient overall health. Treatment of liver metastases is undertaken to prolong survival and to reduce endocrine-related symptoms and hepatic mass-related symptoms.

At present, surgical resection with adequate margins or liver transplantation constitutes the only treatments available with demonstrated curative potential for hepatic tumors. However, most hepatic tumors are unresectable at diagnosis due either to anatomic location, number of lesions, or underlying liver reserve. Patients may also have comorbid conditions and do not qualify for surgical resection. Milan criteria can aid in determining eligibility for transplantation. Milan criteria include tumor size less than 5 cm, no more than 3 foci with each not exceeding 3 cm, absence of local invasion, and absence of extrahepatic involvement. Patients with resectable HCC are also potentially eligible for a liver transplant. However, the availability of liver donors limits its use.

Radiofrequency ablation

RFA is a procedure in which a needle electrode is inserted into a tumor either percutaneously, through a laparoscope, or through an open incision. The electrode is heated by a high frequency, alternating current, which destroys tissue in a 3- to 5-cm sphere of the electrode. RFA has been investigated as a treatment for unresectable hepatic tumors, both as a primary intervention and as a bridge to liver transplant. In the latter setting, RFA is being tested to determine whether it can reduce the incidence of tumor progression in patients awaiting transplantation, thus maintaining patients' candidacy for liver transplantation. Transhepatic arterial chemoembolization, microwave ablation, cryoablation, radiation embolization (yttrium-90 microspheres), hepatic resection, liver transplantation (in carefully selected individuals), and radiofrequency ablation have a 5-year survival of greater than 50% and are considered curative.

The National Comprehensive Cancer Network (NCCN)

The NCCN clinical practice guidelines for hepatocellular carcinoma (V1.2025) state the following with Category 2A recommendations in the Principles of Locoregional Therapy-Ablation section:

• All tumors should be amenable to ablation such that the tumor and, in the case of thermal ablation, a margin of normal tissue is treated. A margin is not expected following percutaneous ethanol injection.
• Tumors should be in a location accessible for percutaneous/laparoscopic/open approaches for ablation.
• Caution should be exercised when ablating lesions near major vessels, major bile ducts, diaphragm, and other intra-abdominal organs.
• Ablation alone may be curative in treating tumors less than or equal to 3 cm. In well-selected patients with small properly located tumors, ablation should be considered as definitive treatment in the context of a multidisciplinary review. Lesions 3 to 5 cm may be treated to prolong survival using arterially directed therapies, or with combination of an arterially directed therapy and ablation as long as tumor location is accessible for ablation.
• Unresectable/inoperable lesions greater than 5 cm should be considered for treatment using arterially directed therapy, systemic therapy, or radiation therapy, or RT

Tumor Ablation Resection is the standard approach for the local treatment of resectable metastatic colon cancer. However, patients with liver or lung oligometastases can also be considered for tumor ablation therapy, particularly in cases that may not be optimal for resection. Ablative techniques include radiofrequency ablation (RFA, microwave ablation (MWA), cryoablation, and electro-coagulation (irreversible electroporation). Per the NCCN, there is extensive evidence on the use of RFA as a reasonable treatment option for non-surgical candidates and for recurrent disease after hepatectomy with small liver metastases that can be treated with clear margins. Ablative techniques may be considered alone or in conjunction with resection. All original sites of disease need to be amenable to ablation or resection.

Fundamento

Summary of evidence

Primary, operable hepatocellular carcinoma

For individuals who have primary, operable hepatocellular carcinoma (HCC) who receive RFA, the evidence includes randomized controlled trials (RCTs), meta-analyses of RCTs and observational studies. Relevant outcomes are overall survival (OS), disease-specific survival, change in disease status, and morbid events. The majority of data found that patients undergoing surgical resection experienced longer survival outcomes and lower recurrence rates than patients receiving RFA, though complication rates were higher with surgical resection. Results from observational studies have suggested that RFA alone or RFA plus percutaneous ethanol injection could be as effective as resection for small HCC tumors. OS and DFS rates were not significantly different between RFA and surgical resection. Although the exact size cutoffs are debatable, current NCCN guidelines suggest ablation as a treatment option when tumors are 3 cm or smaller. Some studies found that OS was similar in patients receiving RFA or resection when tumor size was 3 cm or less; however, OS was significantly longer in patients undergoing resection if the tumor size was between 3.1 cm and 5 cm. Further study in a multicenter RCT would permit greater certainty whether RFA, with or without other ablative or arterially directed therapies, is as effective as surgical resection in treating HCC tumors 3 cm or smaller. The evidence is insufficient to determine the effects of the technology RFA on health outcomes.

Inoperable hepatocellular carcinoma

For individuals who have inoperable HCC who receive RFA, the evidence includes randomized trials and several systematic reviews and meta-analyses. Relevant outcomes are OS, disease-specific survival, change in disease status, and morbid events. Surgical resection of HCC, compared with RFA, has shown superior survival, supporting the use of RFA for unresectable HCC and for those who are not candidates for surgical resection. Response rates have demonstrated that, in patients with small foci of HCC (less than or equal to 3 lesions), RFA appears to be better than ethanol injection in achieving complete ablation and preventing local recurrence. Three-year survival rates of 80% have been reported. The evidence is sufficient to determine that the technology results in a meaningful improvement in the net health outcome.

Inoperable hepatocellular carcinoma awaiting liver transplant

For individuals who have inoperable HCC awaiting liver transplant who receive RFA, the evidence includes small case series. Relevant outcomes are OS, disease-specific survival, and change in disease status. A number of approaches are used in this patient population, including RFA and other locoregional therapies, particularly transarterial chemoembolization. Locoregional therapy has reduced the dropout rate of patients with HCC awaiting a liver transplant. The evidence is sufficient to determine that the technology results in a meaningful improvement in the net health outcome.

Inoperable hepatic metastases of colorectal origin

For individuals who have inoperable hepatic metastases of colorectal origin who receive RFA, the evidence includes RCTs, systematic reviews and meta-analyses, prospective cohort series, and retrospective case series. Relevant outcomes are OS, disease-specific survival, symptoms, change in disease status, morbid events, quality of life, and treatment-related morbidity. There are no RCTs comparing RFA with alternative treatments for unresectable colorectal liver metastases. However, an RCT assessing RFA combined with chemotherapy found improved survival at 8 years compared with chemotherapy alone. In addition, prospective studies have demonstrated that OS following RFA is at least equivalent to and likely better than that for currently accepted systemic chemotherapy in well-matched patients with unresectable hepatic metastatic colorectal cancer who do not have extrahepatic disease. Results from a number of uncontrolled case series also have suggested RFA of hepatic colorectal cancer metastases produces long-term survival that is at minimum equivalent to but likely superior to historical controls receiving systemic chemotherapy. Evidence to date suggests RFA has fewer deleterious effects on quality of life than chemotherapy and that RFA patients recover quality of life significantly faster than chemotherapy recipients. It should be noted that patients treated with RFA in different series might have had better prognoses than those who had chemotherapy, suggesting patient selection bias might at least partially explain the better outcomes observed following RFA. The evidence is sufficient to determine that the technology results in a meaningful improvement in the net health outcome.

Inoperable hepatic metastases of neuroendocrine origin

For individuals who have inoperable hepatic metastases of neuroendocrine origin who receive RFA, the evidence includes case series and a systematic review of case series. Relevant outcomes are OS, disease-specific survival, symptoms, change in disease status, morbid events, quality of life, and treatment-related morbidity. Most reports of RFA treatment for neuroendocrine liver metastases have assessed small numbers of patients or subsets of patients in reports of multiple ablative methods or very small subsets of larger case series of patients with various diagnoses. The available evidence has indicated that durable tumor and symptom control of neuroendocrine liver metastases can be achieved using RFA in individuals whose symptoms are not controlled by systemic therapy or who are ineligible for resection. The evidence is sufficient to determine that the technology results in a meaningful improvement in the net health outcome.

Hepatic metastases not of colorectal or neuroendocrine origin

For individuals who have inoperable hepatic metastases not of colorectal or neuroendocrine origin who receive RFA, the evidence includes case series and uncontrolled comparative studies and small case series. Relevant outcomes are OS, disease-specific survival, symptoms, change in disease status, morbid events, quality of life, and treatment-related morbidity. Similar to primary HCC, surgical resection appears to have the most favorable outcomes. For patients who are ineligible for resection, RFA may provide a survival benefit. However, the evidence is limited by study designs with a high risk of bias and small sample sizes. The evidence is insufficient to determine the effects of the technology RFA on health outcomes.

Definiciones

Denaturation refers to a change in conditions (temperature, addition of a substance) that causes irreversible change in a protein’s structure.

Extrahepatic refers to outside or unrelated to the liver.

Hepatic pertains to the liver.

Hyperthermia refers to the use of microwave or radiofrequency energy to increase body temperature.

Metastasis is the movement of body cells (especially cancer cells) from one part of the body to another.

Neuroendocrine malignancies refer to a diverse group of tumors, such as carcinoid, islet cell tumors, neuroblastoma, and small-cell carcinomas of the lung.

Exención de responsabilidad

Las políticas médicas de Capital Blue Cross se utilizan para determinar la cobertura de tecnologías, procedimientos, equipos y servicios médicos específicos. Estas políticas médicas no constituyen asesoramiento médico y están sujetas a cambios según lo exija la ley o las pruebas clínicas aplicables de las directrices de tratamiento independientes. Los proveedores que brindan tratamiento son individualmente responsables de los consejos médicos y el tratamiento de los miembros. Estas políticas no son una garantía de cobertura o pago. El pago de las reclamaciones está sujeto a la determinación del programa de beneficios del miembro y la elegibilidad en la fecha del servicio, y a la determinación de que los servicios son médicamente necesarios y apropiados. El procesamiento final de una reclamación se basa en los términos del contrato que se aplican al programa de beneficios de los miembros, incluidas las limitaciones y exclusiones de beneficios. Si un proveedor o miembro tiene alguna pregunta sobre esta política médica, debe comunicarse con Servicios para proveedores o Servicios para miembros de Capital Blue Cross.

Información de codificación

Note: This list of codes may not be all-inclusive, and codes are subject to change at any time. La identificación de un código en esta sección no denota cobertura, ya que la cobertura está determinada por los términos de la información de beneficios del miembro. Además, no todos los servicios cubiertos son elegibles para un reembolso por separado.

Covered when medically necessary:

Referencias

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