Percutaneous tumor ablation with radiofrequency

Abstract

Background: Radiofrequency thermal ablation (RFA) is a new minimally invasive treatment for localized cancer. Minimally invasive surgical options require less resources, time, recovery, and cost, and often offer reduced morbidity and mortality, compared with more invasive methods. To be useful, image-guided, minimally invasive, local treatments will have to meet those expectations without sacrificing efficacy.

Methods: Image-guided, local cancer treatment relies on the assumption that local disease control may improve survival. Recent developments in ablative techniques are being applied to patients with inoperable, small, or solitary liver tumors, recurrent metachronous hereditary renal cell carcinoma, and neoplasms in the bone, lung, breast, and adrenal gland.

Results: Recent refinements in ablation technology enable large tumor volumes to be treated with image-guided needle placement, either percutaneously, laparoscopically, or with open surgery. Local disease control potentially could result in improved survival, or enhanced operability.

Conclusions: Consensus indications in oncology are ill-defined, despite widespread proliferation of the technology. A brief review is presented of the current status of image-guided tumor ablation therapy. More rigorous scientific review, long-term follow-up, and randomized prospective trials are needed to help define the role of RFA in oncology.

FIGURE 1

Solitary hepatocellular carcinoma recurrence before and after percutaneous radiofrequency ablation. (A) Computed tomography (CT) scan before percutaneous ablation with radiofrequency demonstrated a solitary isolated hepatocellular carcinoma recurrence in the liver (arrow) in a patient who had undergone multiple previous liver resections. (B) Enhanced CT scan performed 2 months later demonstrated no enhancement (arrow) in the treatment sphere, which included tumor and a 1-cm margin of adjacent normal liver. Lack of enhancement here in the thermal lesion was consistent with coagulation necrosis and complete treatment.

FIGURE 2

Colorectal carcinoma metastasis to the liver treated with open surgical radiofrequency ablation. (A) Contrast-enhanced computed tomography (CT) scan of the liver demonstrated three adjacent hepatic metastases (arrows) from colorectal carcinoma at the extreme dome of the liver in a difficult-to-treat location adjacent to the inferior vena cava and hepatic veins. (2) Contrast-enhanced CT scan of the liver on the day after treatment demonstrated the thermal lesion encompassing the region of liver containing the metastases, suggesting complete treatment. A pleural effusion also was noted, caused by the proximity of the diaphragm to the thermal lesion.

FIGURE 3

Adrenocortical carcinoma recurrence treated with percutaneous radiofrequency ablation. (A) Contrast-enhanced computed tomography (CT) scan demonstrated enhancing bilobed tumor (arrow) in adrenal bed. (B) CT scan during treatment demonstrated ablation needle (arrows) in tumor. (C) Enhanced CT scan after treatment depicted a lack of enhancement in tumors (arrows) and sliver of adjacent spleen, consistent with coagulative necrosis and cell death. (D) Three-dimensional enhanced CT image with planes cut away demonstrated treated tumor (arrow), with close proximity of adjacent nontarget organs (spleen, pancreas, kidney, stomach).

FIGURE 4

Renal cell carcinoma treated with percutaneous radiofrequency ablation. (A) Contrast-enhanced CT scan of right kidney demonstrated enhancing renal cell carcinoma (arrow). (B) Contrast-enhanced CT scan after percutaneous tumor ablation with a 17-gauge radiofrequency ablation probe demonstrated lack of prior enhancement in tumor (arrow) consistent with complete treatment.