Phase II study of daily sunitinib in FDG-PET-positive, iodine-refractory differentiated thyroid cancer and metastatic medullary carcinoma of the thyroid with functional imaging correlation.

PURPOSE: We conducted a phase II study to assess the efficacy of continuous dosing of sunitinib in patients with flurodeoxyglucose positron emission tomography (FDG-PET)-avid, iodine-refractory well-differentiated thyroid carcinoma (WDTC) and medullary thyroid cancer (MTC) and to assess for early response per FDG-PET. EXPERIMENTAL DESIGN: Patients had metastatic, iodine-refractory WDTC or MTC with FDG-PET-avid disease. Sunitinib was administered at 37.5 mg daily on a continuous basis. The primary end point was response rate per Response Evaluation Criteria in Solid Tumors (RECIST). Secondary end points included toxicity, overall survival, and time to progression. We conducted an exploratory analysis of FDG-PET response after 7 days of treatment. RESULTS: Thirty-five patients were enrolled (7 MTC, 28 WDTC), and 33 patients were evaluable for disease response. The primary end point, objective response rate per RECIST, was 11 patients (31%; 95% confidence interval, 16-47%). There were 1 complete response (3%), 10 partial responses (28%), and 16 patients (46%) with stable disease. Progressive disease was seen in 6 patients (17%). The median time to progression was 12.8 months (95% confidence interval, 8.9 months-not reached). Repeat FDG-PET was done on 22 patients. The median percent change in average standardized uptake values was -11.7%, -13.9%, and 8.6% for patients with RECIST response, stable disease, and progressive disease, respectively. Differences between response categories were statistically significant (P = 0.03). The most common toxicities seen included fatigue (11%), neutropenia (34%), hand/foot syndrome (17%), diarrhea (17%), and leukopenia (31%). One patient on anticoagulation died of gastrointestinal bleeding. CONCLUSION: Continuous administration of sunitinib was effective in patients with iodine-refractory WDTC and MTC. Further study is warranted.

Hyperaldosteronism and pheochromocytoma: new tricks and tests.

Hyperaldosteronism, previously thought to represent only 1% to 2% of cases of hypertension, may cause as much as 25% of hypertension in a primary care setting. The renin/aldosterone ratio is the best test for initial screening, followed by localization if possible. Aldosterone antagonists, such as spironolactone, and surgery are the mainstays of treatment. Pheochromocytomas are rare, but because they are a curable cause of hypertension and potentially fatal if not found, important to diagnose. Clinical presentation is variable; however, if symptoms are present, they usually include hypertension, hyperhydrosis, headaches, or palpitations sometimes occurring in dramatic fashion. Once a diagnosis is entertained, appropriate laboratory confirmation is essential. Positive laboratory confirmation then leads to localization of the tumor for eventual surgical removal. New biochemical tests and imaging procedures are making the difficult job of diagnosing and finding these tumors.