title: Treatment compliance and severe adverse events limit the use of tyrosine kinase inhibitors in refractory thyroid cancer.
abstract: OBJECTIVE
  The aim of the present study was to assess patient compliance with tyrosine kinase inhibitor (TKI) treatment used for refractory and progressive thyroid cancer, in addition to the efficacy and serious adverse events associated with these agents.
  
  
  METHODS
  We retrospectively analyzed data from adult patients with metastatic differentiated or medullary thyroid cancer unresponsive to conventional treatment and treated with TKIs. Patients received treatment until disease progression or onset of serious adverse events, or until they expressed an intention to stop treatment.
  
  
  RESULTS
  Twenty-four patients received TKIs. The median duration of treatment was four (range: 1-19) cycles. The most frequent adverse events were fatigue, nausea, diarrhea, hypertension, and stomatitis, and the most severe were nasal bleeding, diarrhea, heart failure, rhabdomyolysis, renal failure, QT prolongation, neutropenia, and severe fatigue. Dose reduction was required in eight patients, while five decided to terminate TKI therapy because adverse events impaired their everyday activities. During therapy, two patients showed a partial response and three showed stable disease. The lungs were the metastatic sites favoring a response to treatment.
  
  
  CONCLUSIONS
  Patient selection and meticulous pretreatment education are necessary in order to ensure adherence with TKI therapy. If adverse events appear, dose reduction or temporary treatment interruption may be offered because some adverse events resolve with continuation of treatment. In the event of serious adverse events, treatment discontinuation is necessary.
authors.affiliation: Department of Endocrinology, Theagenio Cancer Hospital, Thessaloniki, Greece.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Chrisoulidou
authors.affiliation: Department of Endocrinology, Theagenio Cancer Hospital, Thessaloniki, Greece.
authors.forename: Stylianos
authors.initials: S
authors.lastname: Mandanas
authors.affiliation: Department of Endocrinology, Theagenio Cancer Hospital, Thessaloniki, Greece.
authors.forename: Efterpi
authors.initials: E
authors.lastname: Margaritidou
authors.affiliation: Department of Endocrinology, Theagenio Cancer Hospital, Thessaloniki, Greece.
authors.forename: Lemonia
authors.initials: L
authors.lastname: Mathiopoulou
authors.affiliation: Department of Endocrinology, Theagenio Cancer Hospital, Thessaloniki, Greece.
authors.forename: Maria
authors.initials: M
authors.lastname: Boudina
authors.affiliation: Department of Endocrinology, Theagenio Cancer Hospital, Thessaloniki, Greece.
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Georgopoulos
authors.affiliation: Department of Endocrinology, Theagenio Cancer Hospital, Thessaloniki, Greece.
authors.forename: Kalliopi
authors.initials: K
authors.lastname: Pazaitou-Panayiotou
keywords: TKIs; differentiated thyroid cancer; medullary thyroid carcinoma; sorafenib; sunitinib; vandetanib