Purpose: This study was done to assess the effectiveness and advantages of computed tomography (CT) fluoroscopy as a guide for locating and treating lesions that are not amenable to ultrasound (US) guidance, and to evaluate the CT signs of immediate technical success and the short-term results.
Materials and methods: Over the past year, we selected 14 patients (four women and ten men; mean age 73, range 61-83 years) out of 103 candidates for hepatic radiofrequency ablation (RFA). The 14 lesions comprised seven residual tumours after combined embolisation and US-guided RFA of a large hepatocellular carcinoma (HCC), which were indistinguishable from necrosis or surrounding healthy parenchyma; two HCC nodules in locations that were inaccessible by US; five metastases (two from renal carcinoma, two from colorectal adenocarcinoma and one from lung carcinoma), of which one could not be distinguished from the surrounding healthy parenchyma on US and four were inaccessible by US. Lesion diameters were between 1.4 and 3.5 cm. The procedures were performed in the CT room with anaesthesiological assistance using a coaxial LeVeen needle electrode (14 gauge, 2-to 4-cm array diameter). Immediate technical success was evaluated by multidetector CT (MDCT), and follow-up was carried out with MDCT at 3 and 6 months and yearly thereafter.
Results: Immediate technical success was obtained in 13/14 patients; one case required further placement of the electrode due to incomplete ablation of a hypervascular lesion. In 2/3 metastatic lesions with portal vein supply, there were no recurrences at 3 and 6 months; in 1/3, we observed disease progression, with the appearance of additional nodules at 6 months. The two metastases with arterial supply showed no signs of recurrence at 3 months; one case developed a recurrence along the ablation margin, with the appearance of satellite nodules at 6 months. In two HCC nodules, there was immediate technical success and no recurrence at 3 and 6 months. Of the seven residual tumours of HCC, all treated with immediate technical success, we observed disease progression, with the appearance of satellite nodules at 3 months in one case, at 6 months in another and at 12 months in another; 3/7 patients were free of disease at 12-month follow-up; 1/7 died 5 months later due to causes unrelated to the procedure.
Conclusions: CT fluoroscopy is overcoming the limitations of CT in locating and treating lesions with different hepatic vascularisation and those unamenable to US; furthermore, it reduces the length of the procedure, thanks to the faster and more accurate placement of the needle electrode. MDCT proved to be a reliable method in the assessment of immediate and short-term results of RFA.