Kritische Analyse der Evidenz hinsichtlich des Risikos von Sekundärmalignomen nach Radioiodtherapie in der Behandlung des differenzierten Schilddrüsenkarzinoms

Differentiated thyroid cancer often occurs before the age of 60 and usually has a good prognosis. Therefore, in terms of an indication for radioiodine therapy also long-time adverse effects have to be considered as part of a risk-benefit assessment. As a result, the occurrence of second primary malignancies after radioiodine therapy in the treatment of differentiated thyroid cancer has been investigated multiple times in the last decades. In the first publication from 2020 I was able to identify significant deficiencies in studies from the last 10 years. Therefore, I compiled a more comprehensive review about existing studies and evaluated the quality of evidence with validated tools. The results have been published in 2022. In the course of this work, 5 269 articles have been screened of which 69 have been identified as relevant and have been reviewed. Finally, after applying predefined inclusion and exclusion criteria 10 articles have been included in our analysis. The risk of bias has been assessed in each of these studies and the quality of evidence has been judged across all studies, subsequently. The quality of evidence regarding second primary malignancies and second hematological malignancies after radioiodine therapy, as well as a dose-response-relationship, have been assessed separately. On average the included studies found a 14 % to 84 % increased risk of second primary malignancies. The risk for secondary hematological malignancies had increased by 30 % to 150 % averagely. A risk of bias has been identified in numerous studies. The quality of evidence for second primary malignancies after radioiodine therapy and a dose-response-relationship have been judged as very low and for second hematologic malignancies as low. With regard to the indication for a radioiodine therapy the existing evidence concerning the occurrence of second primary malignancies and second hematologic malignancies after radioiodine therapy should be interpreted with great caution.