Complications of percutaneous lung radiofrequency ablation

Transcription

1 Complications of percutaneous lung radiofrequency ablation Poster No.: C-556 Congress: ECR 2009 Type: Educational Exhibit Topic: Interventional Radiology Authors: A. Afaq, S. Khan, U. Patel, E. Leen; London/UK Keywords: complications, radiofrequency ablation, Lung tumour DOI: /ecr2009/C-556 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 6

2 Learning objectives To review the 1. Principles of use of Radiofrequency Ablation (RFA) in lung tumours. 2. Potential and recognised complications, with consideration of relative frequency. Background RFA has been established in the treatment of liver tumours (1). It is now gaining increasing popularity in the treatment of primary and secondary lung tumours. Although surgical resection offers the best chance of curative treatment for Non Small Cell Lung Cancer (NSCLC) and metastases, the proportion of patients eligible for surgery is only 20-30% and 10% at diagnosis respectively (2,3). Chemotherapy and radiotherapy are used, but are usually palliative measures. The principles of the technique are as follows. The aim is local destruction of lung tumour with limited damage to adjacent tissue. Although it can be performed intraoperatively, the preferred and most widely used method is percutaneous access under CT guidance, with local anaesthesia and sedation. An active electrode is placed in tumour tissue. Alternating Current moves from the electrode to electrosurgical return pads, placed on the patient. As energy moves to and from these two components, ions within the tissue oscillate which result in frictional heating of the tissue. Beyond temperatures of 60 degrees Centigrade, cell death / necrosis occurs around the active electrode, but with minimal damage to surrounding normal tissue (4). Feasibility and safety are supported with continuing trials. Imaging findings OR Procedure details Complications are often classified into 1. Minor - those resulting in no sequale or nominal therapy or a short hospital stay for observation 2. Major - resulting in admission for treatment/ increased level of care or permanent adverse outcome. Several small studies exist on lung RFA, most of which demonstrate feasibility. Studies with intermediate follow up are now being reported with increasing frequency. Page 2 of 6

3 Nomura et al performed a retrospective study on 130 patients who underwent 327 lung RFA sessions. The major complication rate was 18.3% (60/327). These included 50 pneumothoraces requiring chest tube placement, 5 abscesses, 2 cases of aseptic pleuritis and chest wall tumour seeding in one case. The two deaths in this group apparently involved interstitial pneumonia developing in the region surrounding the ablated zone (5). The variation in incidence is demonstrated by reviewing the work of Rossi et al, where 9.5% of patients developed interstitial pneumonia, and Stinke et al who reported a mortality rate of 0.4% (2/493) (6,7). Nomura described minor complications involving small pneumothoraces (not requiring tube placement) which occurred in 95 cases. Sano et al 137 patients in which 337 lesions underwent RFA. The major complication rate was 17.1%. These included pnumothoraces requiring drainage in 25, pleurits in 6, pleural effusions requiring drainage in 4, lung abscesses in 1 and intrapulmonary haemorrhage with haemothorax in one (8). Minor complications included small pneumothoraces in 108, small pleural effusions in 34 and small numbers complaining of haemoptysis, nausea, subcutaneous emphysema, cough, skin burn, atelectasis and subileus. Although no procedural mortality occurred, 2 patients (0.9%) died during the study - one from an intractable pneumothorax, and the other from massive haemoptysis. 57 patients with 112 treatment sessions were studied by Okuma et al. Minor adverse effects including pain, small pleural effusions, small pneumothraces, subcutaneous emphysema and haemoptysis occurred in a total of 67%. Major complications occurred in 8% including sepsis/ abscess formation, large pneumothoraces requiring drainage and one patient with an air embolism (9). In their cohort of 142 patients, with 224 sessions for 392 tumours, Hiraki described the incidence of complications as follows: Small pnumothoraces in 52%, pleural effusions in 19%, and pneumothoraces requiring chest drains in 21%. The latter group were found to be associated with a greater number of tumours being ablated, the use of a cluster electrode and upper lobe involvement (10). The presence of emphysema is well recognised to increase the risk of procedure related pneumothorax. Gillams and Lees recently described factors which may increase the risk of pneumothorax in lung RFA cases. Pneumothorax occurred in 38% of their cohort, 4 of which were larger than 31% of the hemithorax. 8/55 (15%) required aspiration. The needle trajectory through aerated lung was significant on multivarate analysis as a risk factor. However, the number of tumours and number of electrode positions also increased the likelihood of pneumothorax (11). Although there are only relatively small observational studies, the largest and most comprehensive review was reported by Zhu et al recently. These authors found the mean number of lesions treated were The mean size of a lesion was cm. The morbidity rate was %. The mortality rate was 0-5.6%. Pneumothorax occurred in %. Most of these were self limiting, although % required drainage (median 11%) (12). At our institution, pneumothorax is also the commonest complication (see mediafile image entitled 'RFA of lung metastases with a pneumothorax'). We have also experienced one complication of a pericardial effusion during a lung RFA case when a patient coughed at the time of needle entry. (See mediafile images entitled RFA lung tumour with pericardial injury'). Images for this section: Page 3 of 6

4 Fig. 1: Two metastases are demonstrated on the top left CT image. The CT PET image on the top right shows the lesion in the left lower lobe is more metabolically active.the series of lower CT images show a pneumothorax has occured during percutaneous access to the metastases. Page 4 of 6

5 Conclusion RFA continues to gain recognition as a safe and effective minimally invasive treatment option for unresectable lung tumours. The most common complication is pneumothorax. Only very few deaths have been reported secondary to the procedure. As the technique develops and knowledge of higher risk profiles improve, complications are likely to reduce further in the future. Personal Information Dr Asim Afaq, SpR Radiology, Imperial College Healthcare NHS Trust, London. Dr Shazia Khan, SpR Respiratory Medicine, Princess Alexandra Hospital, Harlow. Dr Uday Patel, SpR Radiology, St George's Hospital, London. Professor Edward Leen, Professor of Radiology, Imperial College Healthcare NHS Trust, London. References 1. Curley SA, Izzo F Delrio P et al. Radiofrequency ablation of unresectable primary and metastatic hepatic malignancies: results in 123 patients. Ann Surg 1999;230: Sullivan V, Tran T, Holstrom A et al. Advanced age does not exclude lobectomy for non-small cell lung carcinoma. Chest 2005;128: Jensen AD, Munter MW, Bischoff H et al. Treatment of non-small-cell lung cancer with intensity-modulated radiation therapy in combination with cetuximab: the NEAR protocol. BMC Cancer 2006;6: Fernando HC. Radiofrequency ablation to treat non-small cell lung cancer and pulmonary metastases. Ann Thorac Surg 2008;85:S Nomura M, Yamakado K, Nomoto Y et al. Complications after lung radiofrequency ablation: risk factors for lung inflammation. BJR 2008;81: Rossi S, Di SM, Buscarini E et al. Percutaneous RF interstitial thermal ablation in the treatment of hepatic cancer. AJR Am J Roentgenol 1996;167: Steinke K, Sewell PE, Dupuy et al. Pulmonary radiofrequency ablation - an international study survey. Anticancer Res 2004;24: Sano Y, Kanazawa S, Gobara H. Feasibility of percutaneous radiofrequency ablation for intrathoracic malignancies: a large single-center experience. Cancer 2007;109: Page 5 of 6

6 9. Okumo T T, Matsuoka T, Yamamoto A et al. Frequency and risk factors of various complications after computed tomography-guided radiofrequency ablation of lung tumours. Cardiovasc Intervent Radiol 2008;31: Hiraki T, Tajiri N, Mimura H et al. Pneumothorax, pericardial effusion and chest tube placement after radiofrequency ablation of lung tumours: incidence and risk factors. Radiology 2006;241: Gillams AR, Lees WR. Analysis of the factors associated with radiofrequency ablation-induced pneumothorax. Clin Radiol 2007;62: Zhu JC, Yan TD, Morris DL. A systematic review of radiofrequency ablation for lung tumours. Ann Surg Oncol. 2008;15: Page 6 of 6