Lung Tumor Radiofrequency Ablation: Where Do We Stand?

Abstract

Today, radiofrequency ablation (RFA) of primary and metastatic lung tumor is increasingly used. Because RFA is most often used with curative intent, preablation workup must be a preoperative workup. General anesthesia provides higher feasibility than conscious sedation. The electrode positioning must be performed under computed tomography for sake of accuracy. The delivery of RFA must be adapted to tumor location, with different impedances used when treating tumors with or without pleural contact. The estimated rate of incomplete local treatment at 18 months was 7% (95% confidence interval, 3-14) per tumor, with incomplete treatment depicted at 4 months (n = 1), 6 months (n = 2), 9 months (n = 2), and 12 months (n = 2). Overall survival and lung disease-free survival at 18 months were, respectively, 71 and 34%. Size is a key point for tumor selection because large size is predictive of incomplete local treatment and poor survival. The ratio of ablation volume relative to tumor volume is predictive of complete ablation. Follow-up computed tomography that relies on the size of the ablation zone demonstrates the presence of incomplete ablation. Positron emission tomography might be an interesting option. Chest tube placement for pneumothorax is reported in 8 to 12%. Alveolar hemorrhage and postprocedure hemoptysis occurred in approximately 10% of procedures and rarely required specific treatment. Death was mostly related to single-lung patients and hilar tumors. No modification of forced expiratory volume in the first second between pre- and post-RFA at 2 months was found. RFA in the lung provides a high local efficacy rate. The use of RFA as a palliative tool in combination with chemotherapy remains to be explored.

Standards of Practice: Guidelines for Thermal Ablation of Primary and Secondary Lung Tumors

“…From [26] improves local disease control and survival in patients with NSCLC [32]. In pulmonary metastatic disease, RFA has been mainly performed in patients with metastases from colorectal and lung cancers, renal cell carcinoma, melanoma, hepatocellular carcinoma, and sarcoma [25,31,[33][34][35][36][37][38]. The maximum number of lung metastases that may be ablated is still not clearly defined.…”

“…For percutaneous thermal ablation of lung tumors, lesions with a distance of \1 cm from hilum, large vessel or main bronchi, esophagus, or trachea should be avoided [27,33]. Direct contact with a vessel[3 mm or with the myocardium has been already reported as a negative predictive factor for complete coagulation of lung lesions [46,47].…”

“…There are several parameters for a successful thermoablation of lung tumors, but similar to ablation of liver or renal tumors, one of the most important prognostic factors is the size of the target lesion, with the cutoff value being 3.0 cm [33,47,61,64], with \50% complete necrosis in lesions 3-5 cm in diameter. Similar to surgical data, complete tumor destruction and lack of extrapulmonary disease lead to a survival benefit [65].…”

“…The risks of infectious complications seem to be higher in primary tumors, in compromised lung parenchyma, and in previously irradiated lung. However, prophylactic antibiotics have not been proven to reduce infectious rates [33].…”

Radiofrequency Ablation for Pulmonary Metastases from Gastrointestinal Cancers

“…In an undefi ned subset of patients, RFA warrants evaluation versus surgery for treatment of primary NSCLC; however, this hypothesis is diffi cult to test in a rando mized trial because of the anticipated diffi culties of patients consenting to randomization among very different treatments. 17) Complications RFA treatment of lung tumors is relatively safe, with low mortality and excellent tolerance in terms of respiratory function. However, RFA of lung lesions can lead to some complications; most commonly, pneumothorax.…”