Cure Alveolar Soft Part Sarcoma International (iCureASPS)

Outcomes

Patient charts were examined for demographic data; treatment details; time from the start of treatment to disease progression; history of hypothyroidism; development of hypothyroidism during treatment, including laboratory data and symptoms; whether or not thyroid replacement was started and dose of replacement required; and when or if the hypothyroidism resolved. The time from the start of treatment to development of hypothyroidism also was examined. TSH values were not routinely obtained until late 2006, when reports of hypothyroidism were beginning to be published. Patients were excluded if they did not have a baseline TSH level and at least 1 TSH level while on treatment. Hypothyroidism was defined as any TSH increase above the upper limit of normal (5.0 mIU/L). Thyroid replacement was started at the treating physician’s discretion, generally if the TSH level was >10 mIU/L or if the patient had clinically significant symptoms thought to be due to hypothyroidism.

Patients with a history of hypothyroidism who were already receiving thyroid replacement at the start of TKI treatment were analyzed separately from the larger study population. To examine thyroid dysfunction in these patients, we followed the dose of thyroid replacement required. A dose increase of ≥25 µg was considered a marker of worsening thyroid function

Patients and Methods

Patients

A retrospective chart review was performed on all patients with histologically confirmed metastatic RCC treated with sunitinib or sorafenib who were seen at the University of Colorado Hospital urological oncology clinic. They were identified from a list of clinic patients with RCC treated from January 1, 2005, to January 1, 2011. Patients were excluded if there was missing or insufficient follow-up information, including a lack of a baseline TSH value or TSH values during treatment. The study population consisted of 78 patients. Some patients had separate therapeutic trials of sunitinib and sorafenib during the study period; consequently, there were a total of 108 treatment periods examined. For patients on 2 separate drug trials, the washout periods were adequate, and there was no evidence of a cross-over effect.