In reply to Drs. Atalar, Caglar, and Ozyar

摘要

To the Editor: We thank Drs. Atalar, Caglar, and Ozyar for their comments on stereotactic body radiotherapy (SBRT) for a patient with implanted cardiac pacemakers (ICPs). They reported on 1 patient who died 1 month after SBRT with cardiac problems probably unrelated to RT. However, they suggested the establishment of a new guideline for ICPs and implantable cardioverter defibrillators (ICDs) in the era of SBRT and image-guided RT.Our nation-wide survey conducted by the Japan Conformal External Beam Radiotherapy Group (J-CERG) did not include any patients who died after SBRT with malfunction of ICPs and ICDs (1).When a tumor was situated at the same level of the ICP, the computed tomography image of the ICP would be accompanied by severe metallic artifacts. These computed tomography images are not suitable for SBRT planning. Even in such a case, SBRT can be indicated when the position of the subcutaneous ICP can be changed by the patient raising their hands upward.A direct radiation beam through the ICP should be avoided. Also, when a tumor is situated just below the chest wall of the ICP, I would recommend the cardiologists to replace the ICP to an abdominal position.Another Japanese prospective survey of patients with ICP and ICD found 1 case of malfunction in a patient with prostate cancer treated by intensity-modulated RT to the prostate. Even when the ICP is not situated at the same tumor level and no beam passes through the ICP, they recommended precautions during the planning and administration of RT (2).