Unusual widespread metastatic presentation of mixed medullary-follicular thyroid carcinoma.

Mixed medullary-follicular thyroid carcinoma (MMFTC) is a rare tumor with a metastatic behavior that has not been fully appreciated. Scintigraphy and radioiodine entrapment propensity of its metastases remains largely undescribed. The authors present a case of MMFTC with widespread bone and soft-tissue metastases, where every known site of metastases concentrated radioiodine intensely.

Sodium bicarbonate-augmented stress thallium myocardial scintigraphy.

It is well known that sodium bicarbonate in pharmacological doses induces transient alkalosis, causing intracellular transport of serum potassium. The aims of this study were (a) to investigate whether, in humans, myocardial thallium-201 uptake can be augmented by pretreatment with a single bolus of sodium bicarbonate at a pharmacological dose, (b) to verify general safety aspects of the intervention and (c) to evaluate the clinical implications of augmentation of (201)Tl uptake, if any. Routine exercise myocardial scintigraphy was performed twice in eight adult volunteers (five normal and three abnormal), once without intervention and the second time (within a week) following intravenous administration of sodium bicarbonate (88 mEq in 50 ml) as a slow bolus 1 h prior to the injection of (201)Tl.