Fabian Pitoia and Fernando Jerkovich
The stratification of patients with differentiated thyroid cancer based on their initial risk of recurrence, according to specific clinical, histopathological and perioperative data, is an important starting point for tailoring the follow-up during the first 1–2 years after initial therapy (surgery with or without radioiodine ablation). However, risk of recurrence re-stratification based on new clinical data that becomes available after considering the response to treatment (dynamic risk assessment) provides a more accurate prediction of the status at final follow-up and a more individualized approach. In this review, we summarized the available data regarding dynamic risk of recurrence and the suggested management of differentiated thyroid cancer patients according to the response to treatment. The use of this strategy is crucial to avoid overtreatment and intensive follow-up of the vast majority of patients who will have a very good prognosis and, on the other hand, focus therapeutic efforts on those patients who will have a worse prognosis. In the future, molecular biology analysis of the tumors and well-designed prospective studies will probably refine the risk of recurrence prediction.
Marcia S Brose, Johannes Smit, Chia-Chi Lin, Fabian Pitoia, Marc Fellous, Yoriko DeSanctis, Martin Schlumberger, Masayuki Tori and Iwao Sugitani
There are limited treatment options for patients with radioactive iodine refractory, progressive differentiated thyroid cancer. Although there is consensus that multikinase inhibitor therapy should be considered in patients with progressive disease with considerable tumor load or symptomatic disease, uncertainty exists on the optimal timing to treat with a multikinase inhibitor, especially for asymptomatic patients. RIFTOS MKI is an international, prospective, open-label, multicenter, noninterventional study with the primary objective to compare the time to symptomatic progression from study entry in asymptomatic patients with radioactive iodine refractory, progressive differentiated thyroid cancer for whom there is a decision to initiate multikinase inhibitors at study entry (cohort 1) with those for whom there is a decision to not initiate multikinase inhibitors at study entry (cohort 2). Secondary endpoints are overall survival and progression-free survival, which will be compared between cohorts 1 and 2. Additional secondary endpoints are postprogression survival from time of symptomatic progression, duration of and response to each systemic treatment regimen and dosing of sorafenib throughout the treatment period. Asymptomatic, multikinase inhibitor-naive patients aged ≥18 years with histologically/cytologically documented differentiated thyroid cancer that is radioactive iodine refractory are eligible. Patients may receive any therapy for differentiated thyroid cancer, including sorafenib or other multikinase inhibitors if indicated and decided on by the treating physician. In total, 700 patients are estimated to be enrolled from >20 countries. Final analysis will be performed once the last enrolled patient has been followed up with for 24 months (ClinicalTrials.gov identifier: Nbib2303444).