The Korean Journal of Nuclear Medicine (대한핵의학회지)
- Volume 33 Issue 4
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- Pages.422-429
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- 1999
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- 1225-6714(pISSN)
Radiation Absorbed Dose Measurement after I-131 Metaiodobenzylguanidine Treatment in a patient with Pheochromycytoma
갈색세포종 환자에서 Medical Internal Radiation Dose법을 이용한 I-131 Metaiodobenzylguanidine 치료 후 흡수선량 평가
- Yang, Weon-Il (Department of Nuclear Medicine, Korea Cancer Center Hospital) ;
- Kim, Byeung-Il (Department of Nuclear Medicine, Korea Cancer Center Hospital) ;
- Lee, Jae-Sung (Department of Nuclear Medicine, Korea Cancer Center Hospital) ;
- Lee, Jung-Rim (Department of Nuclear Medicine, Korea Cancer Center Hospital) ;
- Choi, Chang-Woon (Department of Nuclear Medicine, Korea Cancer Center Hospital) ;
- Lim, Sang-Moo (Department of Nuclear Medicine, Korea Cancer Center Hospital) ;
- Hong, Sung-Woon (Department of Nuclear Medicine, Korea Cancer Center Hospital)
- 양원일 (원자력병원 핵의학과) ;
- 김병일 (원자력병원 핵의학과) ;
- 이재성 (원자력병원 핵의학과) ;
- 이정림 (원자력병원 핵의학과) ;
- 최창운 (원자력병원 핵의학과) ;
- 임상무 (원자력병원 핵의학과) ;
- 홍성운 (원자력병원 핵의학과)
- Published : 1999.08.30
Abstract
Purpose: The measurement of radiation absorbed dose is useful to predict the response after I-131 labeled metaiodobenzylguanidine (MIBG) therapy and determine therapy dose in patients with unresectable or malignant pheochromocytoma. We estimated the absorbed dose in tumor tissue after high dose I-131 MIBG in a patient with pheochromocytoma using a gamma camera and Medical Internal Radiation Dose (MIRD) formula. Materials and Methods: A 64-year old female patient with pheochromocytoma who had multiple metastases of mediastinum, right kidney and periaortic lymph nodes, received 74 GBq (200 mCi) of I-131 MIBG. We obtained anterior and posterior images at 0.5, 16, 24, 64 and 145 hours after treatment. Two standard sources of 37 and 74 MBq of I-131 were imaged simultaneously. Cummulated I-131 MIBG uptake in tumor tissue was calculated after the correction of background activity, attenuation, system sensitivity and count loss at a high count rate. Results: The calculated absorbed radiation dose was 32-63 Gy/ 74 GBq, which was lower than the known dose for tumor remission (150-200 Gy). follow-up studies at 1 month showed minimally reduced tumor size on computed tomography, and mildly reduced I-131 MIBG uptake. Conclusion: We estimated radiation absorbed dose after therapeutic I-131 MIBG using a gamma camera and MIRD formula, which can be peformed in a clinical nuclear medicine laboratory. Our results suggest that the measurement of radiation absorbed dose in I-131 MIBG therapy is feasible as a routine clinical practice that can guide further treatment plan. The accuracy of dose measurement and correlation with clinical outcome should be evaluated further.
목적: 근치적 절제술이 불가능하거나 전이를 동반한 악성 갈색세포종 환자의 I-131 MIBG 치료 시 흡수선량의 평가는 치료 효과 예측 및 치료용량 결정에 중요하다. 저자들은 갈색세포종 환자에서 I-131 MIBG 치료 후 감마카메라와 MIRD법을 이용하여 흡수선량을 평가하고자 본 연구를 시행하였다. 대상 및 방법: 종격동, 우측 신장 및 대동맥주위 림프절등에 전이가 확인된 악성 갈색세포종 환자에서 74 GBq I-131 MIBG 투여 후 양쪽 목옆에 37 MBq 와 74 MBq의 표준선원을 놓고 각각 0.5, 16, 24, 64, 145시간에 감마카메라로 전 후면영상 얻었다. 배후방사능 보정과 불응시간 보정 그리고 감쇠 보정후 MIRD법을 이용하여 표적조직의 흡수선량을 구하였다. 결과: 병소 각각에서 약