Radiofrequency ablation of unresectable hepatic malignancies: lessons learned.

Radiofrequency ablation (RFA) is increasingly used for the local destruction of unresectable hepatic malignancies. Relative contraindications include tumors in proximity to vital structures that may be injured by RFA and lesions whose size exceeds the ablation capabilities of the probe system employed. Given current technology, we believe that RFA should be cautiously utilized for lesions greater than 5 cm in diameter. Open (celiotomy) and laparoscopic approaches to RFA allow intraoperative ultrasonography, which may demonstrate occult hepatic disease. In addition, RFA performed via celiotomy can be accompanied by resection or cryosurgical ablation, and isolation of the liver from adjacent organs. Percutaneous RFA should be reserved for patients who cannot undergo general anesthesia, those with recurrent or progressive lesions, and those with smaller lesions sufficiently isolated from adjacent organs. Complications may be minimized when these approaches are selectively applied.

Radiofrequency ablation of 231 unresectable hepatic tumors: indications, limitations, and complications.

BACKGROUND: Radiofrequency ablation (RFA) is increasingly used for the local destruction of unresectable hepatic malignancies. There is little information on its optimal approach or potential complications. METHODS: Since late 1997, we have undertaken 91 RFA procedures to ablate 231 unresectable primary or metastatic liver tumors in 84 patients. RFA was performed via celiotomy (n = 39), laparoscopy (n = 27), or a percutaneous approach (n = 25). Patients were followed with spiral computed tomographic (CT) scans at 1 to 2 weeks postprocedure and then every 3 months for 2 years. RESULTS: Intraoperative ultrasound (IOUS) detected intrahepatic disease not evident on the preoperative scans of 25 of 66 patients (38%) undergoing RFA via celiotomy or laparoscopy. In 38 of 84 patients (45%), RFA was combined with resection or cryosurgical ablation (CSA), or both. RFA was used to treat an average of 2.8 lesions per patient, and the median size of treated lesions was 2 cm (range, 0.3-9 cm). The average hospital stay was 3.6 days overall (1.8 days for percutaneous and laparoscopic cases). Ten patients underwent a second RFA procedure (sequential ablations) and, in one case, a third RFA procedure for large (one patient), progressive (seven patients), and/or recurrent (three patients) lesions. Seven (8%) patients had complications: one skin burn; one postoperative hemorrhage; two simple hepatic abscesses; one hepatic abscess associated with diaphragmatic heat necrosis following sequential percutaneous ablations of a large lesion; one postoperative myocardial infarction; and one liver failure. There were three deaths, one (1%) of which was directly related to the RFA procedure. Three of the complications, including one RFA-related death, occurred after percutaneous RFA. At a median follow-up of 9 months (range, 1-27 months), 15 patients (18%) had recurrences at an RFA site, and 36 patients (43%) remained clinically free of disease. CONCLUSIONS: Celiotomy or laparoscopic approaches are preferred for RFA because they allow IOUS, which may demonstrate occult hepatic disease. Operative RFA also allows concomitant resection, CSA, or placement of a hepatic artery infusion pump, and isolation of the liver from adjacent organs. Percutaneous RFA should be reserved for patients at high risk for anesthesia, those with recurrent or progressive lesions, and those with smaller lesions sufficiently isolated from adjacent organs. Complications may be minimized when these approaches are applied selectively.

Radiofrequency ablation: a minimally invasive technique with multiple applications.

PURPOSE: Radiofrequency ablation (RFA) of soft tissue, which has recently been approved by the United States Food and Drug Administration, destroys tumor cells by delivering an electrical current through a 15-gauge needle. This study evaluated RFA for patients with hepatic malignancies considered unresectable because of their distribution, their number, and/or the presence of liver dysfunction. PATIENTS AND METHODS: Between November 1997 and February 1999, 50 patients with 132 unresectable hepatic metastases underwent RFA of tumors from 0.5 to 9 cm in diameter. There were 41 colorectal metastases in 22 patients, 13 hepatomas in seven patients, 37 neuroendocrine metastases in six patients, and 41 noncolorectal metastases in 15 patients. Real-time ultrasonography was used to guide RFA, and lesions were ablated by applying temperatures of approximately 100 degrees C for 8 minutes. Overlapping ablations were used for larger lesions. In patients with multiple lesions, RFA was performed simultaneously with cryosurgery, resection, and/or hepatic arterial infusion. RESULTS: RFA was undertaken percutaneously on an outpatient basis in 13 patients (25 lesions). The remaining patients underwent RFA via laparoscopy (21 patients; 58 lesions) or celiotomy (16 patients; 49 lesions); mean hospital stay was 1 and 5 days, respectively. RFA was the sole therapy in 28 patients and was additional therapy in 22 patients. At a median follow-up of 6 months, 27 patients were free of disease, 17 were alive with disease, and six had died of their disease (three colon, three melanoma). Three patients whose disease recurred at a prior RFA site underwent successful percutaneous RFA. Overall, there was a significant postoperative reduction in levels of carcinoembryonic antigen, alpha-fetoprotein, serotonin, and 5-hydroxyindoleacetic acid. Intraoperative ultrasonography identified unrecognized hepatic lesions in 12 of 37 patients (32%); these lesions were successfully ablated. When performed with cryosurgery, RFA reduced the morbidity of multiple freezes. DISCUSSION: RFA is a safe and effective alternative for the ablation of unresectable hepatic malignancies and when used adjunctively can reduce the morbidity of cryosurgery. Percutaneous and laparoscopic RFA can be performed effectively with less than 24 hours of hospitalization. Intraoperative ultrasonography is essential for accurate staging.

Radiofrequency ablation: a novel primary and adjunctive ablative technique for hepatic malignancies.

The majority of primary and metastatic tumors of the liver are not amenable to surgical resection at presentation. Radiofrequency ablation (RFA) is a new modality for local tumor destruction with minimal local and systemic complications. We prospectively reviewed the experience with RFA at a single institute as a primary or adjunctive ablative technique in the treatment of hepatic malignancies. Between November 1997 and December 1998, 30 patients with primary or metastatic hepatic lesions were treated with RFA at the John Wayne Cancer Institute and the Cancer Center at Century City Hospital. Pathology of the treated lesions included colorectal metastases (29 in 14 patients), neuroendocrine metastases (29 in 4 patients), noncolorectal metastases (29 in 9 patients), and hepatocellular carcinoma (6 in 3 patients). Twelve patients underwent RFA laparoscopically, 12 at celiotomy, and the remaining 6 patients had percutaneous ablation. RFA was the only procedure in 17 patients, whereas the remainder underwent a combination of RFA and other procedures including resection, cryosurgical ablation, and hepatic artery infusion pump placement. Median length of stay for all patients was 6 days (2 days for laparoscopic patients). A single complication of a delayed intrahepatic abscess was noted in this series (3%). There have been no deaths associated with RFA. At a median follow-up of 5 months, 16 patients remain disease free, and 10 are alive with disease. RFA is a safe and effective method of tumor ablation for hepatic malignancies. This technique can be performed laparoscopically, at celiotomy, or percutaneously and can be used as a primary technique or in conjunction with other interventional procedures.