Single group study to evaluate the feasibility and complications of radiofrequency ablation and usefulness of post treatment position emission tomography in lung tumours
© Kang et al; licensee BioMed Central Ltd. 2004
Received: 23 May 2004
Accepted: 06 September 2004
Published: 06 September 2004
There is genuine need to develop interventional treatment options for management of lung tumors. Radiofrequency ablation (RFA) is one such alternative being promoted to treat lung tumors recently. Larger studies should help define RFA's further development. Furthermore fluorodeoxyglucose positron emission tomography (PET) has been reported to be an accurate indicator of treatment response in variety of tumors. This study focuses on the evaluating the feasibility of RFA and usefulness of PET scan in lung tumors after RFA procedure.
Patients and methods
Between November 1999 and May 2002, 50 patients with primary or metastasis pulmonary tumors underwent RFA procedure. The electrode was guided to the target areas using computerized tomography (CT). Tumors smaller than 3.5 cm were given single RFA, while tumors larger than 3.5 cm received RFA to multiple sites. Maximum 4 lesions or 6 target areas were treated during one operating procedure. Whole body and/or lung PET images were acquired; identical site CT images and chest X-ray were taken 1 week before and after RFA.
Of the 50 patients, 17 had single lesions while rest had multiple lesions. Tumors smaller than 3.5 cm were completely dissipated after RFA. In tumors larger than 3.5 cm, the part within 3.5 cm diameter dissipated. While CT showed that tumor image became larger 1 to 2 weeks after RFA procedure. PET demonstrated tumor destruction in 70% cases, compared to 38% in CT.
The present study shows RFA to be safe and effective treatment option for lung tumors. PET is superior to CT in evaluation the effectiveness of RFA treatment shortly after the procedure.
Lung cancer continues to be the leading cause of cancer deaths in United States . The overall prognosis of lung cancer is still dismal despite all current early detection and treatment efforts. Only about 20–25% of lung cancers can potentially be cured by surgery. The majority of patients presents with locally advanced or metastatic disease, and treatments essentially rely on external beam irradiation, chemotherapy or a combination of both . Thus other interventional palliative treatment options have been developed for these lesions.
Radiofrequency ablation (RFA), is an imaging-guided percutaneous ablative procedure, that has been suggested to be an effective treatment option for patients with non-small cell lung cancer (NSCLC) and metastatic disease who are not suitable candidates for surgery [3, 4]. Guided by computed tomography (CT), physicians are able to localize the tumor and determine the optimal approach. During RFA, current passing through tissue from the active electrode leads to ion agitation and frictional heat generation. This leads to irreparable cellular damage and coagulation necrosis . Recently a number of studies reported its application in malignant lung tumours. Accurate assessment of treatment response remains one of the major problems.
PET has been reported to be an accurate indicator of treatment response in variety of tumors [13–17]. However, its use has been limited to evaluating disease stage in lung tumors [18–24]. PET imaging, provides proliferation and metabolism information, is sensitive and specific to diagnose malignant lesions from benign. Coleman and colleagues has provided substantial information in evaluating the role of PET in management of lung cancers [21–23]. In this report we focus on evaluating the feasibility of RFA, its complication and on evaluating the role of PET on RFA response in lung tumors.
Patients and methods
Patients (n = 50)
Primary lung tumors
Metastases from breast
Metastases from colon
Metastases from other places
No. of patient with lesions
Total lesions received RFA
Patients received a chest X-ray and CT for preoperative evaluation and a repeat scan after RFA procedure. A PET scan was performed one week after the treatment.
The Radiofrequency ablation was carried out using RF-2000 generator and related software purchased from Radio Therapeutics Corporation, USA; PET imaging was done using an Advance 2 Scanner (General Electric Medical Systems, WI, USA).
Patients received general anesthesia along with local infiltration of Lidocaine. The electrodes were directed to target areas during RFA procedure using CT scan. The initial power applied was 50 W, which was subsequently increased to a maximum 90 W over several minutes. RFA continued for 5 to 15 min until roll off was achieved, which continued for 2 min to stop. Tumors smaller than 3.5 cm were given full heating energy only once, while tumors larger than 3.5 cm received multiple RFA to different areas. Maximum 4 lesions or 6 target areas were treated during one procedure.
Complications of Radiofrequency ablation
Patients (n = 50)
Early effectiveness of RFA by various techniques
Tumor destruction demonstrated
All 50 patients received
After RFA procedure a number of complications were seen. Fever and/or congested pneumonia were commonest complications seen in 32% of patients; however, they were cured in a week with antibiotics treatment. Pneumothorax occurred during procedures in 18% and the patients were treated with aspiration. Five of these had small pneumothorax that did not require and treatment. One patient had hemothorax which required intercostals drainage (ICD) which was removed 2 days later. These were no life threatening events or deaths.
Since RFA ablates lung tumors directly and locally, marginal tissues surrounding the tumor are frequently partially damaged leading to occasional pneumonia. It is difficult for regular CT and/or chest X-rays to discriminate pathological-physiological tissue damage and fibrillation from the treatment effect of RFA. PET on the other hand provides information on functional and metabolic activity anatomically, and is the only available technique which can specifically diagnose tumors or necrosis after surgery and radiotherapy effectively . Our experience too proves that PET is particularly superior to CT in its ability to evaluate the effectiveness of RFA treatment early after therapy.
RFA is a relatively noninvasive, well-tolerated approach. It could destruct tumor completely within the effective diameter while avoiding the surgery, side effects of radiotherapy and toxicity of high dose chemotherapy. Our observations suggest that RFA can kill lung tumors smaller than 3.5 cm after a single RFA procedure. The effect of RFA appears to be limited within 3.5 cm diameter area with the current instruments. However, this also suggests that RFA may not damage the normal tissues surrounding the small tumors. The malignant lesions dissipated in 1 to 2 weeks, while the surrounding tissue stayed intact. While at this period regular chest CT and chest X-ray may show enlarged lesion images. This is in agreement with other reports. With improvements in technology, RFA in combination with other options may further reduce the morbidity and mortality of cancer deaths . Though complications do occur, they are usually curable. RFA results in a higher rate of complete necrosis and requires fewer treatment cycles compared to traditional chemotherapy or radiotherapy. Besides CT guidance help to localize the tumor and determine the optimal approach further optimizes specific of targeting the tumor. For patients with non-small cell lung malignancy who are not candidates for surgery owing to poor cardio respiratory reserve, RFA alone or followed by conventional radiation therapy or chemotherapy may prove to be a treatment option . For patients with metastatic disease, RFA may be suitable for treatment of a small tumor or reduce symptoms caused by large tumor burden. This technique can be used as a primary technique or in conjunction with other interventional procedures . Further randomized controlled trials comparing RFA with conventional palliative treatment are needed before RFA can be accepted as a routine treatment modality. Survival of patient and quality of life issues too need be addressed.
Despite inherent deficiency of trial design our single group study clearly demonstrates that RFA can be an effective treatment option for lung tumors. Unlike other interventional techniques, RFA provide controlled regions of coagulation necrosis with a single application to an area with 3.5 cm diameter. RFA may cure small lung tumor, reduce tumor burden in larger lesions and may be combined with external beam radiation and/or systemic chemotherapy for further improvements. PET provides functional and metabolic activity anatomically and is particularly superior to CT in evaluation the effectiveness shortly after RFA procedure. Absence of follow-up information and randomization in the current study are two major fallacies which need to be addressed in subsequent studies.
- Williams MD, Sandler AB: The epidemiology of lung cancer. Cancer Treat Res. 2001, 105: 31-52.View ArticlePubMed
- Noppen N: Interventional palliative treatment options for lung cancer. Ann Oncol. 2002, 13 Suppl 4: 247-250.View ArticlePubMed
- Dupuy DE, Mayo-Smith WW, Abbott GF, DiPetrillo T: Clinical applications of radio-frequency tumor ablation in the thorax. Radiographics. 2002, 22 Spec No: S259-69.View ArticlePubMed
- Chhajed PN, Tamm M: Radiofrequency heat ablation for lung tumors: potential applications. Med Sci Monit. 2003, 9: ED5-7.PubMed
- Gazelle GS, Goldberg SN, Solbiati L, Livraghi T: Tumor ablation with radio-frequency energy. Radiology. 2000, 217: 633-646.View ArticlePubMed
- Wong CY, Salem R, Raman S, Gates VL, Dworkin HJ: Evaluating 90Y-glass microsphere treatment response of unresectable colorectal liver metastases by [18F]FDG PET: a comparison with CT or MRI. Eur J Nucl Med Mol Imaging. 2002, 29: 815-820. 10.1007/s00259-002-0787-4.View ArticlePubMed
- Wang W, Larson SM, Fazzari M, Tickoo SK, Kolbert K, Sgouros G, Yeung H, Macapinlac H, Rosai J, Robbins RJ: Prognostic value of [18F]fluorodeoxyglucose positron emission tomographic scanning in patients with thyroid cancer. J Clin Endocrinol Metab. 2000, 85: 1107-1113. 10.1210/jc.85.3.1107.PubMed
- Price DT, Coleman RE, Liao RP, Robertson CN, Polascik TJ, DeGrado TR: Comparison of [18 F]fluorocholine and [18 F]fluorodeoxyglucose for positron emission tomography of androgen dependent and androgen independent prostate cancer. J Urol. 2002, 168: 273-280. 10.1097/00005392-200207000-00090.View ArticlePubMed
- Voth M, Opfermann T, Gottschild D: [The value of fluorodeoxyglucose positron emission tomography (FDG-PET) in differentiation of pancreatic lesions]. Zentralbl Chir. 2003, 128: 375-378. 10.1055/s-2003-40030.View ArticlePubMed
- Lowe VJ, Dunphy FR, Varvares M, Kim H, Wittry M, Dunphy CH, Dunleavy T, McDonough E, Minster J, Fletcher JW, Boyd JH: Evaluation of chemotherapy response in patients with advanced head and neck cancer using [F-18]fluorodeoxyglucose positron emission tomography. Head Neck. 1997, 19: 666-674. 10.1002/(SICI)1097-0347(199712)19:8<666::AID-HED4>3.3.CO;2-C.View ArticlePubMed
- Peschina W: [F-18 fluorodeoxyglucose positron emission tomography in lung lesions]. Wien Med Wochenschr. 2002, 152: 265-268. 10.1046/j.1563-258X.2002.02019.x.View ArticlePubMed
- Berlangieri SU, Scott AM, Knight SR, Fitt GJ, Hennessy OF, Tochon-Danguy HJ, Clarke CP, McKay WJ: F-18 fluorodeoxyglucose positron emission tomography in the non-invasive staging of non-small cell lung cancer. Eur J Cardiothorac Surg. 1999, 16 Suppl 1: S25-30.View ArticlePubMed
- Hunter GJ, Hamberg LM, Choi N, Jain RK, McCloud T, Fischman AJ: Dynamic T1-weighted magnetic resonance imaging and positron emission tomography in patients with lung cancer: correlating vascular physiology with glucose metabolism. Clin Cancer Res. 1998, 4: 949-955.PubMed
- Coleman RE: PET in lung cancer staging. Q J Nucl Med. 2001, 45: 231-234.PubMed
- Coleman RE: Value of FDG-PET scanning in management of lung cancer. Lancet. 2002, 359: 1361-1362. 10.1016/S0140-6736(02)08388-5.View ArticlePubMed
- Gonzalez-Stawinski GV, Lemaire A, Merchant F, O'Halloran E, Coleman RE, Harpole DH, D'Amico TA: A comparative analysis of positron emission tomography and mediastinoscopy in staging non-small cell lung cancer. J Thorac Cardiovasc Surg. 2003, 126: 1900-1905. 10.1016/S0022-5223(03)01036-5.View ArticlePubMed
- Marom EM, McAdams HP, Erasmus JJ, Goodman PC, Culhane DK, Coleman RE, Herndon JE, Patz E. F., Jr.: Staging non-small cell lung cancer with whole-body PET. Radiology. 1999, 212: 803-809.View ArticlePubMed
- Burt BM, Humm JL, Kooby DA, Squire OD, Mastorides S, Larson SM, Fong Y: Using positron emission tomography with [(18)F]FDG to predict tumor behavior in experimental colorectal cancer. Neoplasia. 2001, 3: 189-195. 10.1038/sj.neo.7900147.PubMed CentralView ArticlePubMed
- Coleman RE: FDG imaging. Nucl Med Biol. 2000, 27: 689-690. 10.1016/S0969-8051(00)00139-6.View ArticlePubMed
- Liao WJ, Luo RC, Kang SJ, Wu HB, Wang CB, Luo YL, Zhang MJ: Investigation of short-term therapy results for radiofrequency ablation by positron emission tomography. Di Yi Jun Yi Da Xue Xue Bao. 2002, 22: 376-377.PubMed
- Kostakoglu L, Goldsmith SJ: 18F-FDG PET evaluation of the response to therapy for lymphoma and for breast, lung, and colorectal carcinoma. J Nucl Med. 2003, 44: 224-239.PubMed
- Akhurst T, Downey RJ, Ginsberg MS, Gonen M, Bains M, Korst R, Ginsberg RJ, Rusch VW, Larson SM: An initial experience with FDG-PET in the imaging of residual disease after induction therapy for lung cancer. Ann Thorac Surg. 2002, 73: 259-64; discussion 264-6. 10.1016/S0003-4975(01)03257-X.View ArticlePubMed
- Herrera LJ, Fernando HC, Perry Y, Gooding WE, Buenaventura PO, Christie NA, Luketich JD: Radiofrequency ablation of pulmonary malignant tumors in nonsurgical candidates. J Thorac Cardiovasc Surg. 2003, 125: 929-937. 10.1067/mtc.2003.18.View ArticlePubMed
- Rose DM, Allegra DP, Bostick PJ, Foshag LJ, Bilchik AJ: Radiofrequency ablation: a novel primary and adjunctive ablative technique for hepatic malignancies. Am Surg. 1999, 65: 1009-1014.PubMed
This article is published under license to BioMed Central Ltd. This is an open-access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.