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Percutaneous radiofrequency thermal ablation of renal cell carcinoma: Is it possible a day-hospital treatment?
International Journal of Surgery 6 (2008) S31–S35
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Percutaneous radiofrequency thermal ablation of renal cell carcinoma: Is it possible a day-hospital treatment? Gianpaolo Carrafiello a, *, Domenico Lagana` a, Andrea Ianniello a, Monica Mangini a, Federico Fontana a, Elisa Cotta a, Laura Concollato a, Alberto Marconi b, Chiara Recaldini a, Gianlorenzo Dionigi c, Francesca Rovera c, Luigi Boni c, Salvatore Cuffari d, Carlo Fugazzola a a
Department of Radiology, University of Insubria, Varese, Italy Department of Urology, Hospital of Varese, Varse, Italy Department of Surgical Sciences, University of Insubria, Varese, Italy d Service of Anaesthesiology, Hospital of Varese, Varese, Italy b c
a r t i c l e i n f o
a b s t r a c t
Article history: Available online 14 December 2008
Purpose: The aim of this study is to evaluate the feasibility of the procedure in day-hospital and discuss prognostic factors, efficacy and complications of percutaneous radiofrequency ablation in the treatment of renal cell carcinoma. Materials and methods: Between January 2003 and August 2008, 26 patients (mean age 79, range 70– 87 years, 15 men and 11 women) affected by 27 kidney tumoral lesions, 25 RCC and two renal oncocitome (one patient was affected by two RCC), undergo 29 treatments of RFA (three patients underwent two treatments due to residual tumor at the CT performed 1 month after the first treatment). Three out of 26 patients had only one kidney due to progressed nephrectomy because of RCC; three/26 patients were carriers of oncological comorbidity while four/26 patients were carriers of medical comorbidity. The remaining 16/26 patients refused the surgical option. The lesions had a diameter between 1 and 4 cm (average diameter 2.4 cm). Seventeen of the 27 lesions were exophytic, five/27 parenchymal, three/27 was central while two/27 was mixed. All the lesions had been characterized either by CT or MRI. On the basis of the same investigation the feasibility of the radiofrequency procedure was verified. For all the procedures the RF type 3000Ò radiofrequency generator system was used together with the LeVeenÒ ago-electrode. Twenty-one lesions out of 27 were treated under ultrasound guidance while six/27 lesions under the CT guide. After the procedure a US control was performed to exclude early complications and the same day the patients were discharged from hospital: the procedure was performed in day-hospital. Results: The technical success of the procedure was obtained in all cases (100%). After the procedure, 18 patients, without complications and comorbidity, were discharged from hospital the same day, seven patients with comorbidity were kept under observation for one night while one patient was hospitalized. The primary success of the treatment, rated with CT or MRI after 1 month, was obtained in 25/27 of the cases. In two/27 lesion, an incomplete ablation was obtained; for this reason these patients underwent a second treatment and after 6 month of a regular follow-up, no more neoplastic tissue was identified. During the follow-up there were no signs of disease in any patients. No major peri-procedural complications were recorded; only one patient had to be assisted for the appearance of a peri renal liquid (urinoma) and a thin pneumothorax layer that resolved completely in few days after the procedure. Conclusions: Preliminary results with RFA of RCC are promising. Radiofrequency thermal ablation could prove to be a useful treatment for patients who are unsuitable for surgery; in this study we demonstrate the feasibility of the treatment in day-hospital for selected patients. Ó 2008 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.
Keywords: Renal cell carcinoma Percutaneous treatment Radiofrequency thermal ablation of renal cell carcinoma
1. Introduction * Corresponding author. Vascular and Interventional Radiology, Department of Radiology, University of Insubria, 21100 Varese, Italy. Tel.: þ39 033 227 8770; fax: þ39 033 227 8656. E-mail address: [email protected] (G. Carrafiello).
Renal cell carcinoma (RCC) is the most common primary parenchymal malignancy of the kidney and accounts for 2% of all new cancers annually in the United States.1
1743-9191/$ – see front matter Ó 2008 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.ijsu.2008.12.034
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Renal cell carcinoma is frequently discovered incidentally because of the increasing use of imaging techniques.2,3 In almost two thirds of cases, RCC currently diagnosed are incidental findings in asymptomatic patients.2 The traditional standard treatment for localized RCC is partial or radical nephrectomy, but this method is not ideal for treating all tumors because some patients are unable or unwilling to undergo surgery or would have limited or no functional renal tissue remaining after standard therapy. One possible alternative treatment for such patients is radiofrequency ablation (RFA). We reviewed our experience with 26 patients who underwent RFA for renal neoplasm to evaluate prognostic factors, efficacy and complications of treatment.
2. Materials and methods Between January 2003 and August 2008, 26 patients (mean age 79, range 70–87 years, 15 men and 11 women) affected by 27 kidney tumoral lesions, 25 RCC and two renal oncocitome (one patient was affected by two RCC), undergo 29 treatments of RFA (two patients underwent two treatments due to residual tumor at the CT performed 1 month after the first treatment). All patients were unsuitable to the surgical treatment. Three out of 26 patients had only one kidney due to progressed nephrectomy because of RCC; three/26 patients were carriers of oncological comorbidity (pulmonary carcinoma, gastric carcinoma) while four/26 patients were carriers of medical comorbidity (aortic aneurysm in two cases and chronic renal insufficiency in the other two patients). The remaining 16/26 patients refused the surgical option. The lesions had a diameter between 1 and 4 cm (average diameter 2.4 cm). In one patient, two lesions were treated in one single session. In accordance with the classification proposed by Gervais,4,5 17/ 27 lesions were found to be exophytic, five/27 parenchymal, three/ 27 central while two/27 was mixed. Seventeen lesions were situated on the left kidney, and 10 on the right one. The lesions had been characterized by CT (LightSpeedPlusÒ / GE / Milwaukee / USA or Aquilion 64 / Toshiba / Tokyo /Japan) in 25/26 patients while in one/26 patients, was performed MRI (Eclipse / Picker-Marconi /1.5 T). On the basis of the same investigation the feasibility of the radiofrequency procedure was verified. For all tumors with a diameter 3 cm was performed renal biopsy by means of an 21 Gauge needle (Biomodl); in two cases was performed renal biopsy by means of an 18 Gauge needle, which confirmed the diagnosis of renal oncocitome. For the other patients, no biopsy was carried out in consideration of the risks connected with the puncture (bleeding, seeding, artero/venous fistulas). In seven cases was utilized contrast enhancement to visualize the lesions (SONOVUE). Twenty-one lesions out of 27 were treated under ultrasound (US) guidance (Technos MPXÒ, Esaote, Genova, Italy; iU22 Philips, Eindhoven, The Netherlands), 5/27 lesions were treated under CT guidance (Aquilion 64 / Toshiba / Tokyo/ Japan). For all devices, the skin at the site of the planned needle puncture was anaesthetized with 1% lidocaine. The patients were treated under deep sedation according to the principles of ‘‘monitored anaesthesia care’’ receiving propofol (50–120 mg), alfentanyl (0.5–1 mg) and mydazolam (1–3 mg). All patients received oxygen during the procedures. Continuous monitoring of heart rate, electrocardiographic tracing, oxygen saturation, and respiratory rate were obtained, and blood pressure was determined every 4 min.
For all procedures the RF type 3000Ò radiofrequency generator system was used together with the LeVeenÒ ago-electrode (Fig. 1). In one case the LeVeen 4 cm needle was used, in 10 cases the LeVeen 3.5 cm needle was used, and in 12 cases was the LeVeen 3 cm, and in four cases the LeVeen 2 cm needle was used. At the end of the procedure a US control was performed to exclude major complications [1 – require therapy or minor hospitalization (<48 h); 2 – require major therapy, unplanned increase in the level of care, prolonged hospitalization (>48 h); 3 – permanent adverse sequelae; and 4 – death] and minor complications [1 – no therapy, no consequence; and 2 – nominal therapy, no consequence; includes overnight admission for observation only].6 The patients with major complications were kept under observation in hospital for at least one night; the others patients without complications and clinical or oncological comorbidity were discharged from hospital the same day of the procedure. We defined the technical success as the correct positioning of the needle inside the lesion. The patients were then taken through a follow-up visit by means of CT or MRI at 1, 3, 6 and 12 month intervals after the procedure and then once per year. Primary success was defined as no enhancement or enlargement of the treated lesions, and this finding is consistent with local control; any focal enhancement in the ablated lesion was be considered indicative of residual or recurrent tumor. The patients with clinical and oncological comorbidity (6) were kept under observation in hospital. During the follow -up period major complications and minor complications are scheduled. 3. Results The technical success of the procedure was obtained in all cases (100%). The primary success of the treatment, assessed when CT or MRI completed after 1 month, was obtained in 25/27 of the cases in which no enhancement or enlargement of the treated lesion was observed (Figs. 2 and 3). In two/27 lesions, an incomplete ablation was obtained; for this reason this patient underwent a second treatment and after 6 months of a regular follow-up, no more neoplastic tissue was identified. No major peri-procedural complications were recorded; only one patient had to be assisted for the appearance of a perirenal fluid collection (urinoma) and a thin pneumothorax (PNX). Subsequent examinations (US of the abdomen and X-ray film of the chest in two
Fig. 1. LeVeenÒ ago-electrode.
G. Carrafiello et al. / International Journal of Surgery 6 (2008) S31–S35
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Fig. 2. a: Enhanced CT scan shows the RF multitines electrode in place within the upper pole mass. b: Immediate postablation contrast enhanced CT scan shows stranding and fascial thickening (arrow). Arrowhead indicates the ablation zone.
positions), demonstrated the complete resolution of the urinoma within 3 days of the procedure and the complete disappearance of the of the PNX 12 h after the treatment. Eighteen of 26 patients were discharged from hospital after US control the same day of the procedure while the others with oncological or clinical comorbidity were kept under observation for at least one night. None of the patients has shown a renal failure after the procedure. During the follow-up there were no signs of the recurrence in any of the patients. All the patients underwent CT or MRI controls for a period of 2 years in one case, 18 months in two cases, 1 year in four cases, of 9 months in two cases, of 6 months in six cases, of 3 months in two cases, of 2 months in one and of 1 month in eight cases. The average value of follow-up is 7 months. 4. Discussion From the first indication of renal neoplasm treatment by RFA, 10 years have passed and the subsequent reports have highlighted a progressive numerical increase in patients undergoing such a cure with satisfactory results.7 In our Institution we performed more than 500 RFA. The treatment is safe and minimally invasive, than in patients without clinical or oncological comorbidity and post-
Fig. 3. a: Pre-ablation contrast enhanced CT scan shows a small exophytic tumor (arrow). b. Contrast-enhanced CT scan obtained 4 weeks after RFA demonstrates an area (arrow) of non-enhancing soft-tissue attenuation (ablation zone).
treatment complications, we kept them in observation only for 1 day: the procedure was performed in day-hospital. Potential candidates for thermal ablation fall into three general categories: 1 – patients who are poor operative candidates as a result of inadequate renal function and/or comorbid disease; 2 – patients at high risk for the development of additional RCC in the future (patients with von Hippel–Lindau syndrome, hereditary papillary cell carcinoma, or hereditary clear-cell carcinoma) in whom the least invasive nephron-sparing approach is desirable; and 3 – patients refusing surgical option.9 From literature it can be seen how the most important predictive factors of the success of the treatment are the localization and size of the neoplasm.4–11 The exophytic lesions are the ones with the best results due to the so-called ‘‘oven effect’’ determined by the perirenal fat which represents an optimal isolating material reducing the dispersion of thermal energy. The issue is the opposite if one considers the parenchymal or central lesions, since the renal parenchymal is richly vascularized and the renal pelvis is often in contact with the lesion to be treated. In both cases there is a marked thermal dispersion due to the ematic flow and for the urine contained in the calicial-pelvis.4,5
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In our experience, 17/27 exophytic lesions made to undergo regular follow-up, were completely ablated after the first treatment. There were no signs of residual disease in the central lesions, which differs from that written in literature, but probably the cause in our series is due to a not so large number of patients. In literature it is reviewed that another predictive factor for the success is represented by the size of the lesions.12,13 The lesions treated in the personal series showed a diameter of 2.4 cm (range 1 –4 cm) mainly in agreement with the previous experience, in which the average diameter was 2.2 cm (range 0.6–8.9 cm).7,14–48 It is well known that an increase in the diameter of the lesion corresponds to a significant reduction in the response to treatment. The larger tumors require multiple overlapping ablations and in same cases return visits for additional ablation session.4 Our data agrees with previous experiences which are exclusively considering those studies with an average follow-up of at least 36 months in which about 15 patients were treated;9–11,16–21 the procedure has proved to be resolute (no disease) in 387/420 lesions <3 cm and 69/92 lesions between 3 and 9 cm. Nevertheless the size of the lesion does not present an absolute limit in RFA treatment of renal neoplasm in relation to the availability of different strategies such as the simultaneous positioning of several needles, overlapping of several treatments, the injection of saline solutions, application of radiofrequency with pulsed technology, arterious adjuvante and occlusion pharmacological treatments.13,30 In our experience, the lesions greater than 3 cm (six lesions) were efficacy treated after two overlapping treatments. This evidence substantially coincides in what many authors had previously underlined; tumors larger than 3 cm can be treated successfully but sometimes required multiple RFA and sessions.9–11,14,16,31–33 The US guide was used in 21/27 cases, while for the remaining six the CT guide was used while data in literature showed CT preference for the Anglo–Saxon countries and US guide preference in other experiences.7,10–16,17–48
From a comparison with literature, taking into consideration the greater cases (about 15 patients treated) with follow-up greater than 7 months (average of 12.6 months, range 7 months – 2.3 years),10–12,17–21,28 it can be seen that our study is weighted by an higher percentage of success rate (100 against 96%). The reasons for this result are to be found in two factors: size of tumor and localization. In the personal experience six lesions had a dimension larger than 3 cm and most of the lesions treated in our Institution were exophytic (17/27) Table 1. The procedure, is characterized by a low percentage of complications as can be seen from the literature:10,12–20,30–38 in our experience no major peri-procedural complications occurred. In only one patient we observed a thin PNX and a perirenal urinoma that did not bring about alterations of the ematochemical parameters. The perirenal urinoma and PNX represent a recognized complications as reported in the Classification system used by The Society of International Radiology.8 Subsequent controls performed with US of the abdomen and Xray film of the chest in two projections, showed the complete resolution of the perirenal urinoma after 3 days after the procedure and complete re-absorption of the PNX after 12 h.10,12–16,18–20,30–38 On the basis of our experience, the procedure can be performed in day -hospital in patients without comorbidity and complications. 5. Conclusions Radiofrequency thermal ablation could prove to be a useful treatment for patients who are unsuitable for surgery; in this study we demonstrate the feasibility of the treatment in day-hospital for selected patients. In general, RCC smaller than 3 cm can in diameter are ideal for ablation, with near-perfect success rates on post procedural imaging; most tumors smaller than 3 cm often can be treated successfully in a single session. Tumors between 3 and 5 cm in diameter can also be treated successfully with confidence, but multiple ablations and sessions may be required; the presence of
Table 1 Personal experience. N /age/sex
N lesions
Diameter (cm)
Position
Side
Treatment
Guidance
Needle
Primary success
Follow-up
1/73/M 2/82/M 3/81/F 4/85/F 5/81/F 6/80/F 7/70/M 8/70/M 9/80/F 10/81/F 11/79/F 12/83/M 13/78/M 14/81/M 15/81/M 16/80/M
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2
Left Right Left Right Left Left Left Left Left Left Left Left Left Left Right Left– Right Right Right Left Right Left Right Left Right Right Left
TC TC US US US TC US US US US US US US US US US
LeVeen LeVeen LeVeen LeVeen LeVeen LeVeen LeVeen LeVeen LeVeen LeVeen LeVeen LeVeen LeVeen LeVeen LeVeen LeVeen
3 cm 3 cm 3 cm 4 cm 3 cm 3 cm 3 cm 2 cm 3.5 cm 3 cm 3 cm 2 cm 3.5 cm 3.5 cm 3.5 cm 3.5 cm
Complete ablation Complete ablation Complete ablation Residual lesion Complete ablation Complete ablation Complete ablation Complete ablation Complete ablation Complete ablation Complete ablation Complete ablation Complete ablation Complete ablation Complete ablation Complete ablation
12 months: complete ablation 12 months complete ablation 9 months: complete ablation 6 months: complete ablation 6 months: complete ablation 3 months: complete ablation 9 months: complete ablation 12 months: complete ablation 2 years: complete ablation 6 months: complete ablation 6 months: complete ablation 18 months: complete ablation 18 months: complete ablation 1 month: complete ablation 1 month: complete ablation 1 month: complete ablation
1 1 1 1 1 1 1 1 1 1
Parenchymal Central Parenchymal Mixed Exophytic Exophytic Exophytic Exophytic Exophytic Exophytic Exophytic Exophytic Exophytic Exophytic Exophytic Exophytic Central Exophytic Exophytic Exophytic Parenchymal Parenchymal Exophytic Exophytic Parenchymal Central Mixed
1 1 1 2 1 1 2 1 1 1 1 1 1 1 1 1
17/85/M 18/81/M 19/84/F 20/70/F 21/81/F 22/71/M 23/74/M 24/85/F 25/72/M 26/87/M
2.6 2 3 4 1 4 1.3 3 1.8 3.6 4 2.7 1.5 3 1.2 3.2 2.4 1 3 4 1 1.3 2.2 1.5 3 2.5 2
1 1 1 1 1 1 1 1 1 1
US US US US US US US US TC TC
LeVeen LeVeen LeVeen LeVeen LeVeen LeVeen LeVeen LeVeen LeVeen LeVeen
2 cm 3.5 cm 3.5 cm 2 cm 3.5 cm 3.5 cm 3 cm 3 cm 3 cm 3 cm
Complete Complete Complete Complete Complete Complete Complete Complete Complete Complete
1 month: complete ablation 1 month: complete ablation 6 months: complete ablation 2 months: complete ablation 3 months: complete ablation 1 month: complete ablation 12 months: complete ablation 1 month: complete ablation 1 month: complete ablation 6 months: complete ablation
ablation ablation ablation ablation ablation ablation ablation ablation ablation ablation
G. Carrafiello et al. / International Journal of Surgery 6 (2008) S31–S35
radiologically detected residual tumor can be in fact retreated and there does not appear to be a high risk of systemic spread from foci of residual tumor. The location of the tumor (exophytic, parenchymal, mixed or central) also influences ablation results. Parenchymal, mixed or central tumor may be more difficult to be treated: the presence of a central component in a RCC larger than 3 cm is reported to be a significant predictor of failure.4,7 Additional long term data regarding local and systemic relapse and survival are needed before the oncology efficacy of this technique can be verified for therapy of RCCs. Current findings suggest that RFA for RCC is an acceptable alternative to surgery in well selected patients.
Conflict of interest None declared. Funding None declared. Ethical approval None declared. References 1. Landis SH, Murray T, Bolden S, et al. Cancer statistics. CA Cancer J Clin 1999;1999(48):8–31. 2. Homma Y, Kawabe K, Kitamura T, et al. Increased incidental detection and reduced mortality in renal cancer: recent retrospective analysis at eight institutions. Int J Urol 1995;2:77–80. 3. Bretheau D, Lechevallier E, Eghazarian C, et al. Prognostic significance of incidental renal cell carcinoma. Eur J Urol 1995;5:319–23. 4. Gervais DA, McGovern FJ, Arellano RS, et al. Renal cell carcinoma: clinical experience and technical success with radio-frequency ablation of 42 tumors. Radiology 2003;226:417–24. 5. Karashima T, Inoue K, Shimamoto T, et al. Conservative therapy by percutaneous radiofrequency ablation of renal cell carcinomasdtherapeutic experiments of four patients with seven renal tumors. Hinyokika Kiyo 2006 Apr;52(4):241–7 (in Japanese). 6. Sacks D, McClenny T, Cardella JF, et al. Society of interventional radiology clinical practice guidelines. J Vasc Interv Radiol 2003;14:199–202. 7. Zlotta AR, Wildschutz T, Raviv G, et al. Radiofrequency interstitial tumor ablation (RITA) is a possible new modality for treatment of renal cancer: ex vivo and in vivo experience. J Endourol 1997;11:251–8. 8. Clark TW, Millward SF, Gervais DA, et al. Reporting standards for percutaneous thermal ablation of renal cell carcinoma. J Vasc Interv Radiol 2006;17:1563–70. 9. Raj GV, Reddan DJ, Hoey MF, et al. Management of small renal tumors with radiofrequency ablation. Urology 2003;61:23–9. 10. Farrell MA, Charboneau WJ, DiMarco DS, et al. Imaging-guided radiofrequency ablation of solid renal tumors. Am J Roentgenol 2003;180:1509–13. 11. Majo-Smith WW, Dupuy DE, Parikh PM, et al. Imaging-guided percutaneous radiofrequency ablation of solid renal masses: techniques and outcomes of 38 treatment sessions in 32 consecutive patients. Am J Roentgenol 2003;180:1503–8. 12. Su LM, Jarrett TW, Chan DV, et al. Percutaneous computed tomography-guided radiofrequency ablation of renal masses in high surgical risk patients: preliminary results. Urology 2003;(suppl. 4A):26–33. 13. Gazelle GS, Goldberg SN, Solbiati L, et al. Tumor ablation with radio-frequency energy. Radiology 2000;217:633–46. 14. Ogan K, Jacomides L, Dolmatch BL, et al. Percutaneous radiofrequency ablation of renal tumors: technique, limitations, and morbidity. Urology 2002;60:954–8. 15. Pavlovich CP, Walther MM, Choyke PL, et al. Percutaneous radio frequency ablation of small renal tumors: initial results. J Urol 2002;167:110–5. 16. Roy-Chounhury S, Cast JEI, Cooksey G, et al. Early experience with percutaneous radiofrequency ablation of small solid renal masses. Am J Roentgenol 2003;180:1055–61. 17. Ahrar K, Matin S, Wood CG, et al. Percutaneous radiofrequency ablation of renal tumors: technique, complications and outcomes. J Vasc Interv Radiol 2005;16:679–88. 18. Gervais DA, McGovern FJ, Arellano RS, et al. Radiofrequency ablation of renal cell carcinoma: part I, indications, results and role in patient management over a 6-year period and ablation of 100 tumors. Am J Roentgenol 2005;185: 64–71.
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Percutaneous radiofrequency thermal ablation of renal cell carcinoma: Is it possible a day-hospital treatment? Gianpaolo Carrafiello a, *, Domenico Lagana` a, Andrea Ianniello a, Monica Mangini a, Federico Fontana a, Elisa Cotta a, Laura Concollato a, Alberto Marconi b, Chiara Recaldini a, Gianlorenzo Dionigi c, Francesca Rovera c, Luigi Boni c, Salvatore Cuffari d, Carlo Fugazzola a a
Department of Radiology, University of Insubria, Varese, Italy Department of Urology, Hospital of Varese, Varse, Italy Department of Surgical Sciences, University of Insubria, Varese, Italy d Service of Anaesthesiology, Hospital of Varese, Varese, Italy b c
a r t i c l e i n f o
a b s t r a c t
Article history: Available online 14 December 2008
Purpose: The aim of this study is to evaluate the feasibility of the procedure in day-hospital and discuss prognostic factors, efficacy and complications of percutaneous radiofrequency ablation in the treatment of renal cell carcinoma. Materials and methods: Between January 2003 and August 2008, 26 patients (mean age 79, range 70– 87 years, 15 men and 11 women) affected by 27 kidney tumoral lesions, 25 RCC and two renal oncocitome (one patient was affected by two RCC), undergo 29 treatments of RFA (three patients underwent two treatments due to residual tumor at the CT performed 1 month after the first treatment). Three out of 26 patients had only one kidney due to progressed nephrectomy because of RCC; three/26 patients were carriers of oncological comorbidity while four/26 patients were carriers of medical comorbidity. The remaining 16/26 patients refused the surgical option. The lesions had a diameter between 1 and 4 cm (average diameter 2.4 cm). Seventeen of the 27 lesions were exophytic, five/27 parenchymal, three/27 was central while two/27 was mixed. All the lesions had been characterized either by CT or MRI. On the basis of the same investigation the feasibility of the radiofrequency procedure was verified. For all the procedures the RF type 3000Ò radiofrequency generator system was used together with the LeVeenÒ ago-electrode. Twenty-one lesions out of 27 were treated under ultrasound guidance while six/27 lesions under the CT guide. After the procedure a US control was performed to exclude early complications and the same day the patients were discharged from hospital: the procedure was performed in day-hospital. Results: The technical success of the procedure was obtained in all cases (100%). After the procedure, 18 patients, without complications and comorbidity, were discharged from hospital the same day, seven patients with comorbidity were kept under observation for one night while one patient was hospitalized. The primary success of the treatment, rated with CT or MRI after 1 month, was obtained in 25/27 of the cases. In two/27 lesion, an incomplete ablation was obtained; for this reason these patients underwent a second treatment and after 6 month of a regular follow-up, no more neoplastic tissue was identified. During the follow-up there were no signs of disease in any patients. No major peri-procedural complications were recorded; only one patient had to be assisted for the appearance of a peri renal liquid (urinoma) and a thin pneumothorax layer that resolved completely in few days after the procedure. Conclusions: Preliminary results with RFA of RCC are promising. Radiofrequency thermal ablation could prove to be a useful treatment for patients who are unsuitable for surgery; in this study we demonstrate the feasibility of the treatment in day-hospital for selected patients. Ó 2008 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.
Keywords: Renal cell carcinoma Percutaneous treatment Radiofrequency thermal ablation of renal cell carcinoma
1. Introduction * Corresponding author. Vascular and Interventional Radiology, Department of Radiology, University of Insubria, 21100 Varese, Italy. Tel.: þ39 033 227 8770; fax: þ39 033 227 8656. E-mail address: [email protected] (G. Carrafiello).
Renal cell carcinoma (RCC) is the most common primary parenchymal malignancy of the kidney and accounts for 2% of all new cancers annually in the United States.1
1743-9191/$ – see front matter Ó 2008 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.ijsu.2008.12.034
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Renal cell carcinoma is frequently discovered incidentally because of the increasing use of imaging techniques.2,3 In almost two thirds of cases, RCC currently diagnosed are incidental findings in asymptomatic patients.2 The traditional standard treatment for localized RCC is partial or radical nephrectomy, but this method is not ideal for treating all tumors because some patients are unable or unwilling to undergo surgery or would have limited or no functional renal tissue remaining after standard therapy. One possible alternative treatment for such patients is radiofrequency ablation (RFA). We reviewed our experience with 26 patients who underwent RFA for renal neoplasm to evaluate prognostic factors, efficacy and complications of treatment.
2. Materials and methods Between January 2003 and August 2008, 26 patients (mean age 79, range 70–87 years, 15 men and 11 women) affected by 27 kidney tumoral lesions, 25 RCC and two renal oncocitome (one patient was affected by two RCC), undergo 29 treatments of RFA (two patients underwent two treatments due to residual tumor at the CT performed 1 month after the first treatment). All patients were unsuitable to the surgical treatment. Three out of 26 patients had only one kidney due to progressed nephrectomy because of RCC; three/26 patients were carriers of oncological comorbidity (pulmonary carcinoma, gastric carcinoma) while four/26 patients were carriers of medical comorbidity (aortic aneurysm in two cases and chronic renal insufficiency in the other two patients). The remaining 16/26 patients refused the surgical option. The lesions had a diameter between 1 and 4 cm (average diameter 2.4 cm). In one patient, two lesions were treated in one single session. In accordance with the classification proposed by Gervais,4,5 17/ 27 lesions were found to be exophytic, five/27 parenchymal, three/ 27 central while two/27 was mixed. Seventeen lesions were situated on the left kidney, and 10 on the right one. The lesions had been characterized by CT (LightSpeedPlusÒ / GE / Milwaukee / USA or Aquilion 64 / Toshiba / Tokyo /Japan) in 25/26 patients while in one/26 patients, was performed MRI (Eclipse / Picker-Marconi /1.5 T). On the basis of the same investigation the feasibility of the radiofrequency procedure was verified. For all tumors with a diameter 3 cm was performed renal biopsy by means of an 21 Gauge needle (Biomodl); in two cases was performed renal biopsy by means of an 18 Gauge needle, which confirmed the diagnosis of renal oncocitome. For the other patients, no biopsy was carried out in consideration of the risks connected with the puncture (bleeding, seeding, artero/venous fistulas). In seven cases was utilized contrast enhancement to visualize the lesions (SONOVUE). Twenty-one lesions out of 27 were treated under ultrasound (US) guidance (Technos MPXÒ, Esaote, Genova, Italy; iU22 Philips, Eindhoven, The Netherlands), 5/27 lesions were treated under CT guidance (Aquilion 64 / Toshiba / Tokyo/ Japan). For all devices, the skin at the site of the planned needle puncture was anaesthetized with 1% lidocaine. The patients were treated under deep sedation according to the principles of ‘‘monitored anaesthesia care’’ receiving propofol (50–120 mg), alfentanyl (0.5–1 mg) and mydazolam (1–3 mg). All patients received oxygen during the procedures. Continuous monitoring of heart rate, electrocardiographic tracing, oxygen saturation, and respiratory rate were obtained, and blood pressure was determined every 4 min.
For all procedures the RF type 3000Ò radiofrequency generator system was used together with the LeVeenÒ ago-electrode (Fig. 1). In one case the LeVeen 4 cm needle was used, in 10 cases the LeVeen 3.5 cm needle was used, and in 12 cases was the LeVeen 3 cm, and in four cases the LeVeen 2 cm needle was used. At the end of the procedure a US control was performed to exclude major complications [1 – require therapy or minor hospitalization (<48 h); 2 – require major therapy, unplanned increase in the level of care, prolonged hospitalization (>48 h); 3 – permanent adverse sequelae; and 4 – death] and minor complications [1 – no therapy, no consequence; and 2 – nominal therapy, no consequence; includes overnight admission for observation only].6 The patients with major complications were kept under observation in hospital for at least one night; the others patients without complications and clinical or oncological comorbidity were discharged from hospital the same day of the procedure. We defined the technical success as the correct positioning of the needle inside the lesion. The patients were then taken through a follow-up visit by means of CT or MRI at 1, 3, 6 and 12 month intervals after the procedure and then once per year. Primary success was defined as no enhancement or enlargement of the treated lesions, and this finding is consistent with local control; any focal enhancement in the ablated lesion was be considered indicative of residual or recurrent tumor. The patients with clinical and oncological comorbidity (6) were kept under observation in hospital. During the follow -up period major complications and minor complications are scheduled. 3. Results The technical success of the procedure was obtained in all cases (100%). The primary success of the treatment, assessed when CT or MRI completed after 1 month, was obtained in 25/27 of the cases in which no enhancement or enlargement of the treated lesion was observed (Figs. 2 and 3). In two/27 lesions, an incomplete ablation was obtained; for this reason this patient underwent a second treatment and after 6 months of a regular follow-up, no more neoplastic tissue was identified. No major peri-procedural complications were recorded; only one patient had to be assisted for the appearance of a perirenal fluid collection (urinoma) and a thin pneumothorax (PNX). Subsequent examinations (US of the abdomen and X-ray film of the chest in two
Fig. 1. LeVeenÒ ago-electrode.
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Fig. 2. a: Enhanced CT scan shows the RF multitines electrode in place within the upper pole mass. b: Immediate postablation contrast enhanced CT scan shows stranding and fascial thickening (arrow). Arrowhead indicates the ablation zone.
positions), demonstrated the complete resolution of the urinoma within 3 days of the procedure and the complete disappearance of the of the PNX 12 h after the treatment. Eighteen of 26 patients were discharged from hospital after US control the same day of the procedure while the others with oncological or clinical comorbidity were kept under observation for at least one night. None of the patients has shown a renal failure after the procedure. During the follow-up there were no signs of the recurrence in any of the patients. All the patients underwent CT or MRI controls for a period of 2 years in one case, 18 months in two cases, 1 year in four cases, of 9 months in two cases, of 6 months in six cases, of 3 months in two cases, of 2 months in one and of 1 month in eight cases. The average value of follow-up is 7 months. 4. Discussion From the first indication of renal neoplasm treatment by RFA, 10 years have passed and the subsequent reports have highlighted a progressive numerical increase in patients undergoing such a cure with satisfactory results.7 In our Institution we performed more than 500 RFA. The treatment is safe and minimally invasive, than in patients without clinical or oncological comorbidity and post-
Fig. 3. a: Pre-ablation contrast enhanced CT scan shows a small exophytic tumor (arrow). b. Contrast-enhanced CT scan obtained 4 weeks after RFA demonstrates an area (arrow) of non-enhancing soft-tissue attenuation (ablation zone).
treatment complications, we kept them in observation only for 1 day: the procedure was performed in day-hospital. Potential candidates for thermal ablation fall into three general categories: 1 – patients who are poor operative candidates as a result of inadequate renal function and/or comorbid disease; 2 – patients at high risk for the development of additional RCC in the future (patients with von Hippel–Lindau syndrome, hereditary papillary cell carcinoma, or hereditary clear-cell carcinoma) in whom the least invasive nephron-sparing approach is desirable; and 3 – patients refusing surgical option.9 From literature it can be seen how the most important predictive factors of the success of the treatment are the localization and size of the neoplasm.4–11 The exophytic lesions are the ones with the best results due to the so-called ‘‘oven effect’’ determined by the perirenal fat which represents an optimal isolating material reducing the dispersion of thermal energy. The issue is the opposite if one considers the parenchymal or central lesions, since the renal parenchymal is richly vascularized and the renal pelvis is often in contact with the lesion to be treated. In both cases there is a marked thermal dispersion due to the ematic flow and for the urine contained in the calicial-pelvis.4,5
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In our experience, 17/27 exophytic lesions made to undergo regular follow-up, were completely ablated after the first treatment. There were no signs of residual disease in the central lesions, which differs from that written in literature, but probably the cause in our series is due to a not so large number of patients. In literature it is reviewed that another predictive factor for the success is represented by the size of the lesions.12,13 The lesions treated in the personal series showed a diameter of 2.4 cm (range 1 –4 cm) mainly in agreement with the previous experience, in which the average diameter was 2.2 cm (range 0.6–8.9 cm).7,14–48 It is well known that an increase in the diameter of the lesion corresponds to a significant reduction in the response to treatment. The larger tumors require multiple overlapping ablations and in same cases return visits for additional ablation session.4 Our data agrees with previous experiences which are exclusively considering those studies with an average follow-up of at least 36 months in which about 15 patients were treated;9–11,16–21 the procedure has proved to be resolute (no disease) in 387/420 lesions <3 cm and 69/92 lesions between 3 and 9 cm. Nevertheless the size of the lesion does not present an absolute limit in RFA treatment of renal neoplasm in relation to the availability of different strategies such as the simultaneous positioning of several needles, overlapping of several treatments, the injection of saline solutions, application of radiofrequency with pulsed technology, arterious adjuvante and occlusion pharmacological treatments.13,30 In our experience, the lesions greater than 3 cm (six lesions) were efficacy treated after two overlapping treatments. This evidence substantially coincides in what many authors had previously underlined; tumors larger than 3 cm can be treated successfully but sometimes required multiple RFA and sessions.9–11,14,16,31–33 The US guide was used in 21/27 cases, while for the remaining six the CT guide was used while data in literature showed CT preference for the Anglo–Saxon countries and US guide preference in other experiences.7,10–16,17–48
From a comparison with literature, taking into consideration the greater cases (about 15 patients treated) with follow-up greater than 7 months (average of 12.6 months, range 7 months – 2.3 years),10–12,17–21,28 it can be seen that our study is weighted by an higher percentage of success rate (100 against 96%). The reasons for this result are to be found in two factors: size of tumor and localization. In the personal experience six lesions had a dimension larger than 3 cm and most of the lesions treated in our Institution were exophytic (17/27) Table 1. The procedure, is characterized by a low percentage of complications as can be seen from the literature:10,12–20,30–38 in our experience no major peri-procedural complications occurred. In only one patient we observed a thin PNX and a perirenal urinoma that did not bring about alterations of the ematochemical parameters. The perirenal urinoma and PNX represent a recognized complications as reported in the Classification system used by The Society of International Radiology.8 Subsequent controls performed with US of the abdomen and Xray film of the chest in two projections, showed the complete resolution of the perirenal urinoma after 3 days after the procedure and complete re-absorption of the PNX after 12 h.10,12–16,18–20,30–38 On the basis of our experience, the procedure can be performed in day -hospital in patients without comorbidity and complications. 5. Conclusions Radiofrequency thermal ablation could prove to be a useful treatment for patients who are unsuitable for surgery; in this study we demonstrate the feasibility of the treatment in day-hospital for selected patients. In general, RCC smaller than 3 cm can in diameter are ideal for ablation, with near-perfect success rates on post procedural imaging; most tumors smaller than 3 cm often can be treated successfully in a single session. Tumors between 3 and 5 cm in diameter can also be treated successfully with confidence, but multiple ablations and sessions may be required; the presence of
Table 1 Personal experience. N /age/sex
N lesions
Diameter (cm)
Position
Side
Treatment
Guidance
Needle
Primary success
Follow-up
1/73/M 2/82/M 3/81/F 4/85/F 5/81/F 6/80/F 7/70/M 8/70/M 9/80/F 10/81/F 11/79/F 12/83/M 13/78/M 14/81/M 15/81/M 16/80/M
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2
Left Right Left Right Left Left Left Left Left Left Left Left Left Left Right Left– Right Right Right Left Right Left Right Left Right Right Left
TC TC US US US TC US US US US US US US US US US
LeVeen LeVeen LeVeen LeVeen LeVeen LeVeen LeVeen LeVeen LeVeen LeVeen LeVeen LeVeen LeVeen LeVeen LeVeen LeVeen
3 cm 3 cm 3 cm 4 cm 3 cm 3 cm 3 cm 2 cm 3.5 cm 3 cm 3 cm 2 cm 3.5 cm 3.5 cm 3.5 cm 3.5 cm
Complete ablation Complete ablation Complete ablation Residual lesion Complete ablation Complete ablation Complete ablation Complete ablation Complete ablation Complete ablation Complete ablation Complete ablation Complete ablation Complete ablation Complete ablation Complete ablation
12 months: complete ablation 12 months complete ablation 9 months: complete ablation 6 months: complete ablation 6 months: complete ablation 3 months: complete ablation 9 months: complete ablation 12 months: complete ablation 2 years: complete ablation 6 months: complete ablation 6 months: complete ablation 18 months: complete ablation 18 months: complete ablation 1 month: complete ablation 1 month: complete ablation 1 month: complete ablation
1 1 1 1 1 1 1 1 1 1
Parenchymal Central Parenchymal Mixed Exophytic Exophytic Exophytic Exophytic Exophytic Exophytic Exophytic Exophytic Exophytic Exophytic Exophytic Exophytic Central Exophytic Exophytic Exophytic Parenchymal Parenchymal Exophytic Exophytic Parenchymal Central Mixed
1 1 1 2 1 1 2 1 1 1 1 1 1 1 1 1
17/85/M 18/81/M 19/84/F 20/70/F 21/81/F 22/71/M 23/74/M 24/85/F 25/72/M 26/87/M
2.6 2 3 4 1 4 1.3 3 1.8 3.6 4 2.7 1.5 3 1.2 3.2 2.4 1 3 4 1 1.3 2.2 1.5 3 2.5 2
1 1 1 1 1 1 1 1 1 1
US US US US US US US US TC TC
LeVeen LeVeen LeVeen LeVeen LeVeen LeVeen LeVeen LeVeen LeVeen LeVeen
2 cm 3.5 cm 3.5 cm 2 cm 3.5 cm 3.5 cm 3 cm 3 cm 3 cm 3 cm
Complete Complete Complete Complete Complete Complete Complete Complete Complete Complete
1 month: complete ablation 1 month: complete ablation 6 months: complete ablation 2 months: complete ablation 3 months: complete ablation 1 month: complete ablation 12 months: complete ablation 1 month: complete ablation 1 month: complete ablation 6 months: complete ablation
ablation ablation ablation ablation ablation ablation ablation ablation ablation ablation
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radiologically detected residual tumor can be in fact retreated and there does not appear to be a high risk of systemic spread from foci of residual tumor. The location of the tumor (exophytic, parenchymal, mixed or central) also influences ablation results. Parenchymal, mixed or central tumor may be more difficult to be treated: the presence of a central component in a RCC larger than 3 cm is reported to be a significant predictor of failure.4,7 Additional long term data regarding local and systemic relapse and survival are needed before the oncology efficacy of this technique can be verified for therapy of RCCs. Current findings suggest that RFA for RCC is an acceptable alternative to surgery in well selected patients.
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