Cardiovasc Intervent Radiol (2014) 37:554–557 DOI 10.1007/s00270-013-0736-6
LETTER TO THE EDITOR
A Case of Pulmonary Aspergilloma Treated with Radiofrequency Ablation Takao Hiraki • Hideo Gobara • Katsuya Kato Hiroyasu Fujiwara • Toshihiro Iguchi • Yusuke Matsui • Susumu Kanazawa
•
Received: 25 July 2013 / Accepted: 15 August 2013 / Published online: 3 October 2013 Ó Springer Science+Business Media New York and the Cardiovascular and Interventional Radiological Society of Europe (CIRSE) 2013
To the Editor, Progressive aspergilloma should be treated because of the risk of life-threatening hemoptysis, local pulmonary invasion, and disseminated disease. However, antifungal agents are not usually extremely effective, and surgical resection is sometimes inappropriate, mainly because the patients with pulmonary aspergilloma often experience impaired pulmonary function resulting from underlying chronic lung diseases such as tuberculosis, bronchiectasia, lung abscess, and pulmonary emphysema. Therefore, a less invasive therapy for aspergilloma is desired. Radiofrequency (RF) ablation is a thermal therapy that involves heating via ionic agitation, typically at temperatures between 60 and 100 °C. This technique has been demonstrated to be effective for the treatment of lung cancer [1–4]. Aspergillus species are not usually heat
T. Hiraki (&) H. Gobara K. Kato H. Fujiwara T. Iguchi Y. Matsui S. Kanazawa Department of Radiology, Okayama University Medical School, 2-5-1 Kitaku Shikatacho, Okayama 700-8558, Japan e-mail: [email protected] H. Gobara e-mail: [email protected] K. Kato e-mail: [email protected] H. Fujiwara e-mail: [email protected] T. Iguchi e-mail: [email protected] Y. Matsui e-mail: [email protected] S. Kanazawa e-mail: [email protected]
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tolerant; they can be killed by exposure to temperatures of 50–60 °C for 3–4 min [5]. Thus, we assumed that RF ablation could be used for the treatment of aspergilloma. However, to our knowledge, there are no reports on the application of RF ablation for treating aspergilloma. Here we report a case of pulmonary aspergilloma that was treated with RF ablation. A 79-year-old woman had nodules in the pulmonary cavity in the right lower lobe on chest computed tomographic (CT) images. The lesion showed the so-called air crescent sign, indicating pulmonary aspergilloma (Fig. 1A). Periodical CT scans revealed that the lesion gradually enlarged and reached 2.2 9 1.1 cm in diameter. The diagnosis of aspergilloma was pathologically confirmed by CT-guided biopsy. Because the lesion was progressive, surgery was considered, but the patient was not a surgical candidate because of comorbidity. Thus, RF ablation was suggested as an alternative therapy. At our institution, the Institutional Review Board approved the use of RF ablation for localized pulmonary mycosis in 2010. After obtaining informed consent, RF ablation was performed. The patient was placed in the prone position, and standard steel mesh grounding pads were placed on the patient’s thighs. After administration of an epidural anesthetic, a single internally cooled electrode (Cool-Tip; Covidien, Mansfield, Massachusetts) with a 2-cm noninsulated tip was percutaneously introduced into the lesion under CT fluoroscopic guidance (Fig. 1B) and then was connected to an RF generator (CC-1; Covidien). Using an impedance control algorithm, RF energy was applied during internal cooling of the electrode, with a maximum power of 73 W for 12 min. Immediately after the completion of the application, the temperature of the electrode tip was 79 °C. No complications occurred during and after the procedure.
T. Hiraki et al.: Case of Pulmonary Aspergilloma
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Fig. 1 A CT image before RF ablation reveals nodules (arrow) in a cavity, demonstrating the so-called air crescent sign, which is typical of pulmonary aspergilloma. B CT image during RF ablation with the patient in the prone position showing an electrode (arrowheads) being introduced into the lesion (arrow). C CT image 5 days after RF
ablation reveals that the lesion (arrow) is completely involved in the ablation zone (arrowheads), which demonstrates ground-glass opacity surrounded by a dense rim. D Biopsy specimen 7 days after RF ablation reveals fragmented Aspergillus hyphae with destroyed cell wall architecture (Grocott stain)
CT images obtained 5 days later revealed that the lesion was completely involved in the ablation zone (Fig. 1C). CT-guided biopsy was performed 7 days after RF ablation. Specimens exhibited fragmented Aspergillus hyphae with destroyed cell wall architecture, which suggested thermal damage (Fig. 1D). The culture of the biopsy specimen was negative for Aspergillus. During the next 16 months, the ablation zone exhibited continuous shrinkage on CT images (Fig. 2A–C). CT-guided biopsy was repeated 16 months after RF ablation. Five specimens obtained by an 18-gauge cutting biopsy needle were composed mostly of fibrotic tissue but contained a few small (\1 mm in size) clusters of Aspergillus hyphae. The culture of the biopsy specimen was negative for Aspergillus. Thereafter, the ablation zone continued to shrink further and finally resulted in scarlike tissues on CT images 33 months after RF ablation (Fig. 2D, E).
Pulmonary aspergilloma generally forms from saprophytic colonization of preexisting pulmonary cavities of Aspergillus species. Aspergillus species are not usually heat tolerant. As for Aspergillus fumigatus, the most common saprophytic species of Aspergillus in human disease, sporules have a D value (the time required at a certain temperature to kill 90 % of the fungi) of 2.6 min for 63 °C [5]. Hyphae may be much less tolerant to heat than sporules. Based on this fact, we assumed that RF ablation might be effective for treatment of pulmonary aspergilloma. During the procedure, Aspergillus was exposed to high temperatures of up to 79 °C for 12 min. Biopsy specimen at 7 days revealed that RF ablation certainly caused thermal damage to Aspergillus. Involution of the ablation zone, finally leaving only scarlike tissues, suggested that most Aspergillus was killed by RF ablation. However, it should be remembered that the RF ablation
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T. Hiraki et al.: Case of Pulmonary Aspergilloma
Fig. 2 CT images 1 month (A), 3 months (B), 12 months (C), 19 months (D), and 33 months (E) after RF ablation reveal that the ablation zone continues to decrease in size, finally leaving only scarlike tissues
procedure itself may be a risk factor for future development of aspergilloma in cases in which it causes cavitation [6, 7]. In conclusion, this case suggests that RF ablation is effective in the treatment of pulmonary aspergilloma.
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Acknowledgments Grant 22591370.
This work was supported by JSPS KAKENHI
Conflict of interest of interest.
The authors declare that they have no conflict
T. Hiraki et al.: Case of Pulmonary Aspergilloma
References 1. Lencioni R, Crocetti L, Cioni R et al (2008) Radiofrequency ablation of pulmonary tumors response evaluation: a prospective, intention-to-treat, multicenter clinical trial (the ‘‘RAPTURE’’ study). Lancet Oncol 9:621–628 2. Hiraki T, Gobara H, Mimura H et al (2011) Percutaneous radiofrequency ablation of clinical stage I non-small cell lung cancer. J Thorac Cardiovasc Surg 142:24–30 3. Hiraki T, Yamakado K, Ikeda O et al (2011) Percutaneous radiofrequency ablation for pulmonary metastases from hepatocellular carcinoma: results of a multicenter study in Japan. J Vasc Interv Radiol 22:741–748
557 4. Hiraki T, Gobara H, Iishi T et al (2007) Percutaneous radiofrequency ablation for pulmonary metastases from colorectal cancer: midterm results in 27 patients. J Vasc Interv Radiol 18:1264–1269 5. Morozumi S, Fujikawa H, Wauke T, Chiba T (2004) Fungal contamination and its control in foods. Ann Rep Tokyo Metrop Inst Public Health 55:3–12 6. Hiraki T, Gobara H, Mimura H et al (2009) Aspergilloma in a cavity formed after percutaneous radiofrequency ablation for lung cancer. J Vasc Interv Radiol 20:1499–1500 7. Alberti N, Frulio N, Trillaud H et al (2013) Pulmonary aspergilloma in a cavity formed after percutaneous radiofrequency ablation. Cardiovasc Intervent Radiol. doi:10.1007/s00270-0130631-1
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LETTER TO THE EDITOR
A Case of Pulmonary Aspergilloma Treated with Radiofrequency Ablation Takao Hiraki • Hideo Gobara • Katsuya Kato Hiroyasu Fujiwara • Toshihiro Iguchi • Yusuke Matsui • Susumu Kanazawa
•
Received: 25 July 2013 / Accepted: 15 August 2013 / Published online: 3 October 2013 Ó Springer Science+Business Media New York and the Cardiovascular and Interventional Radiological Society of Europe (CIRSE) 2013
To the Editor, Progressive aspergilloma should be treated because of the risk of life-threatening hemoptysis, local pulmonary invasion, and disseminated disease. However, antifungal agents are not usually extremely effective, and surgical resection is sometimes inappropriate, mainly because the patients with pulmonary aspergilloma often experience impaired pulmonary function resulting from underlying chronic lung diseases such as tuberculosis, bronchiectasia, lung abscess, and pulmonary emphysema. Therefore, a less invasive therapy for aspergilloma is desired. Radiofrequency (RF) ablation is a thermal therapy that involves heating via ionic agitation, typically at temperatures between 60 and 100 °C. This technique has been demonstrated to be effective for the treatment of lung cancer [1–4]. Aspergillus species are not usually heat
T. Hiraki (&) H. Gobara K. Kato H. Fujiwara T. Iguchi Y. Matsui S. Kanazawa Department of Radiology, Okayama University Medical School, 2-5-1 Kitaku Shikatacho, Okayama 700-8558, Japan e-mail: [email protected] H. Gobara e-mail: [email protected] K. Kato e-mail: [email protected] H. Fujiwara e-mail: [email protected] T. Iguchi e-mail: [email protected] Y. Matsui e-mail: [email protected] S. Kanazawa e-mail: [email protected]
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tolerant; they can be killed by exposure to temperatures of 50–60 °C for 3–4 min [5]. Thus, we assumed that RF ablation could be used for the treatment of aspergilloma. However, to our knowledge, there are no reports on the application of RF ablation for treating aspergilloma. Here we report a case of pulmonary aspergilloma that was treated with RF ablation. A 79-year-old woman had nodules in the pulmonary cavity in the right lower lobe on chest computed tomographic (CT) images. The lesion showed the so-called air crescent sign, indicating pulmonary aspergilloma (Fig. 1A). Periodical CT scans revealed that the lesion gradually enlarged and reached 2.2 9 1.1 cm in diameter. The diagnosis of aspergilloma was pathologically confirmed by CT-guided biopsy. Because the lesion was progressive, surgery was considered, but the patient was not a surgical candidate because of comorbidity. Thus, RF ablation was suggested as an alternative therapy. At our institution, the Institutional Review Board approved the use of RF ablation for localized pulmonary mycosis in 2010. After obtaining informed consent, RF ablation was performed. The patient was placed in the prone position, and standard steel mesh grounding pads were placed on the patient’s thighs. After administration of an epidural anesthetic, a single internally cooled electrode (Cool-Tip; Covidien, Mansfield, Massachusetts) with a 2-cm noninsulated tip was percutaneously introduced into the lesion under CT fluoroscopic guidance (Fig. 1B) and then was connected to an RF generator (CC-1; Covidien). Using an impedance control algorithm, RF energy was applied during internal cooling of the electrode, with a maximum power of 73 W for 12 min. Immediately after the completion of the application, the temperature of the electrode tip was 79 °C. No complications occurred during and after the procedure.
T. Hiraki et al.: Case of Pulmonary Aspergilloma
555
Fig. 1 A CT image before RF ablation reveals nodules (arrow) in a cavity, demonstrating the so-called air crescent sign, which is typical of pulmonary aspergilloma. B CT image during RF ablation with the patient in the prone position showing an electrode (arrowheads) being introduced into the lesion (arrow). C CT image 5 days after RF
ablation reveals that the lesion (arrow) is completely involved in the ablation zone (arrowheads), which demonstrates ground-glass opacity surrounded by a dense rim. D Biopsy specimen 7 days after RF ablation reveals fragmented Aspergillus hyphae with destroyed cell wall architecture (Grocott stain)
CT images obtained 5 days later revealed that the lesion was completely involved in the ablation zone (Fig. 1C). CT-guided biopsy was performed 7 days after RF ablation. Specimens exhibited fragmented Aspergillus hyphae with destroyed cell wall architecture, which suggested thermal damage (Fig. 1D). The culture of the biopsy specimen was negative for Aspergillus. During the next 16 months, the ablation zone exhibited continuous shrinkage on CT images (Fig. 2A–C). CT-guided biopsy was repeated 16 months after RF ablation. Five specimens obtained by an 18-gauge cutting biopsy needle were composed mostly of fibrotic tissue but contained a few small (\1 mm in size) clusters of Aspergillus hyphae. The culture of the biopsy specimen was negative for Aspergillus. Thereafter, the ablation zone continued to shrink further and finally resulted in scarlike tissues on CT images 33 months after RF ablation (Fig. 2D, E).
Pulmonary aspergilloma generally forms from saprophytic colonization of preexisting pulmonary cavities of Aspergillus species. Aspergillus species are not usually heat tolerant. As for Aspergillus fumigatus, the most common saprophytic species of Aspergillus in human disease, sporules have a D value (the time required at a certain temperature to kill 90 % of the fungi) of 2.6 min for 63 °C [5]. Hyphae may be much less tolerant to heat than sporules. Based on this fact, we assumed that RF ablation might be effective for treatment of pulmonary aspergilloma. During the procedure, Aspergillus was exposed to high temperatures of up to 79 °C for 12 min. Biopsy specimen at 7 days revealed that RF ablation certainly caused thermal damage to Aspergillus. Involution of the ablation zone, finally leaving only scarlike tissues, suggested that most Aspergillus was killed by RF ablation. However, it should be remembered that the RF ablation
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T. Hiraki et al.: Case of Pulmonary Aspergilloma
Fig. 2 CT images 1 month (A), 3 months (B), 12 months (C), 19 months (D), and 33 months (E) after RF ablation reveal that the ablation zone continues to decrease in size, finally leaving only scarlike tissues
procedure itself may be a risk factor for future development of aspergilloma in cases in which it causes cavitation [6, 7]. In conclusion, this case suggests that RF ablation is effective in the treatment of pulmonary aspergilloma.
123
Acknowledgments Grant 22591370.
This work was supported by JSPS KAKENHI
Conflict of interest of interest.
The authors declare that they have no conflict
T. Hiraki et al.: Case of Pulmonary Aspergilloma
References 1. Lencioni R, Crocetti L, Cioni R et al (2008) Radiofrequency ablation of pulmonary tumors response evaluation: a prospective, intention-to-treat, multicenter clinical trial (the ‘‘RAPTURE’’ study). Lancet Oncol 9:621–628 2. Hiraki T, Gobara H, Mimura H et al (2011) Percutaneous radiofrequency ablation of clinical stage I non-small cell lung cancer. J Thorac Cardiovasc Surg 142:24–30 3. Hiraki T, Yamakado K, Ikeda O et al (2011) Percutaneous radiofrequency ablation for pulmonary metastases from hepatocellular carcinoma: results of a multicenter study in Japan. J Vasc Interv Radiol 22:741–748
557 4. Hiraki T, Gobara H, Iishi T et al (2007) Percutaneous radiofrequency ablation for pulmonary metastases from colorectal cancer: midterm results in 27 patients. J Vasc Interv Radiol 18:1264–1269 5. Morozumi S, Fujikawa H, Wauke T, Chiba T (2004) Fungal contamination and its control in foods. Ann Rep Tokyo Metrop Inst Public Health 55:3–12 6. Hiraki T, Gobara H, Mimura H et al (2009) Aspergilloma in a cavity formed after percutaneous radiofrequency ablation for lung cancer. J Vasc Interv Radiol 20:1499–1500 7. Alberti N, Frulio N, Trillaud H et al (2013) Pulmonary aspergilloma in a cavity formed after percutaneous radiofrequency ablation. Cardiovasc Intervent Radiol. doi:10.1007/s00270-0130631-1
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