European Journal of Nuclear Medicine Vol. 27, No. 10, October 2000 Abstract. This prospective, observational study of a co- hort of thyroid cancer patients in Germany focusses on the “real-world” practice in the management of thyroid cancer patients. This report includes data from 2376 pa- tients with primary differentiated thyroid carcinoma first diagnosed in the year 1996. The study reveals consider- able differences in actual practice concerning surgery and radioiodine treatment. The results indicate that con- sensus is lacking with respect to the multimodality treat- ment approach for differentiated thyroid carcinoma. Our analysis represents the most current and comprehensive national assessment of presenting patient characteristics, diagnostic tests, treatment and complications for thyroid cancer. Key words: Differentiated thyroid cancer – Guidelines – Radioiodine – Treatment Eur J Nucl Med (2000) 27:1465–1472 DOI 10.1007/s002590000333 Introduction Because of the rarity and the comparatively low mortality of differentiated thyroid carcinoma, with a 10-year over- all survival rate of more than 85% [1, 2], analyses of out- comes in controlled, randomised, clinical trials are im- practical and consequently unavailable. Recommenda- tions for diagnostic and therapeutic interventions in dif- ferentiated thyroid cancer are mainly based on the analy- sis of retrospective, non-controlled studies [3, 4, 5, 6, 7, 8, 9]. Such studies often address patient cohorts of a cer- tain geographic region treated in the distant past. This focus on specialised clinical settings and atypical or in- sufficiently diverse patient populations means that the findings are of limited external validity. Moreover, com- paring a contemporary intervention with such historical- ly treated groups may overestimate the effectiveness of the former because of the improvements in outcome as- sociated with general improvements in medical care. Given the rapid evolution of medical knowledge and technology, the need for up-to-date information is obvi- ous. Contested areas in the management of thyroid carci- noma are especially the extent of the applied surgery and the most appropriate use of radioactive iodine. Consen- sus and expert-based guidelines for the treatment of dif- ferentiated thyroid cancer are available in Germany, but the actual practice, e.g. the surgical approach, the pro- portion of patients treated with radioiodine, the activity of radioiodine administered and the percentage of short- term adverse effects, remains unknown. In order to an- swer some of these questions, a Patient Care Evaluation Study (PCE study) has been carried out since the year 1996. PCE studies are prospective observational studies in oncology that have been developed by the Commis- sion on Cancer (CoC) of the American College of Sur- geons (ACoS) in the United States. One of the major functions of this organisation is to develop criteria for the periodic evaluation of the care (diagnosis, treatment and follow-up) of patients with specific cancer diseases. PCE studies are based on patient-oriented, treatment-ac- companying tumour documentation that is compiled in all medical facilities involved in cancer care. In this way, detailed information is made available on patient charac- teristics, extent of disease and course of disease with ref- erence to the applied medical interventions. This allows a statistical, mostly explorative analysis of factors that influence the clinical decision-making process, the use of available diagnostic and therapeutic modalities for certain medical conditions and the consequences of cur- Correspondence to: S. Hoelzer, Institute of Medical Informatics, Heinrich-Buff-Ring 44, 35392 Gießen, Germany Original article Current practice of radioiodine treatment in the management of differentiated thyroid cancer in Germany Simon Hoelzer 1 , Dagmar Steiner 2 , Richard Bauer 2 , Christoph Reiners 3 , Jamshid Farahati 3 , Scott A. Hundahl 4 , Joachim Dudeck 1 1 Institute of Medical Informatics, Justus-Liebig-University Giessen, Germany 2 Clinic for Nuclear Medicine, Justus-Liebig-University Giessen, Germany 3 Clinic and Policlinic for Nuclear Medicine, University of Würzburg, Germany 4 Commission on Cancer, American College of Surgeons, Chicago, USA Received 15 April and in revised form 23 June 2000 / Published online: 17 August 2000 © Springer-Verlag 2000