ADVANCES IN PET - PART II 

The Quarterly Journal of Nuclear Medicine and Molecular Imaging 2008 March;52(1):30-6

Copyright © 2008 EDIZIONI MINERVA MEDICA

lingua: Inglese

The role of 124I-PET in diagnosis and treatment of thyroid carcinoma

Lubberink M. ¹, Abdul Fatah S. ², Brans B. ², Hoekstra O. S. ¹, Teule G. J. J. ²

¹ Department of Nuclear Medicine and PET Research VU University Medical Centre, Amsterdam, The Netherlands 2 Department of Nuclear Medicine Maastricht University Hospital, Maastricht, The Netherlands

Iodine-124 is a positron-emitting iodine isotope, enabling measurement of iodine uptake using positron emission tomography (PET). There is a number of situations where the use of 124I-PET/computed tomography (CT) can improve the current clinical practice in the diagnosis and treatment of thyroid cancer. Firstly, 124I-PET/CT can aid in the staging of patients, because of better detection of metastatic disease and measurement of metabolic tumor volume, and thus separate low-risk from high-risk patients. Secondly, the much higher sensitivity and spatial resolution of PET compared to γ scintigraphy can also improve detection of recurrent disease. Furthermore, 124I-PET can be used for patient-specific radioiodine therapy radiation dosimetry. Simultaneous administration of the therapeutic dose of 131I and a tracer dose of 124I allows for accurate measurement of iodine uptake during therapy. The decay scheme of 124I, with few positrons and many γ rays emitted per decay, often simultaneously, poses a challenge to quantitative PET imaging. Improved correction methods and the use of last-generation PET/CT scanners with faster electronics and better energy resolution can overcome this.