Evaluation of methods for localizing parathyroid tumors

Intraoperative identification of parathyroid glands: appraisal of methylene blue staining

Methylene blue administered intravenously in a dose of 5 mg/kg of body weight was employed as an aid to the intraoperative identification of parathyroid glands in 90 patients undergoing surgery for hyperparathyroidism. Staining occurred in 95 percent of adenomas and 86 percent of hyperplastic glands. Normal and suppressed glands stained in 71 and 70 percent of cases, respectively. There were no adverse side effects from the technique. We conclude that preoperative intravenous infusion of methylene blue is a valuable technique that facilitates identification of parathyroid tissue at operation.

Angiographic localization of parathyroid adenomas

The angiographic and operative findings in 35 patients with primary hyperparathyroidism were compared. A non-selective angiography is proposed. The appearance of solid and cystic parathyroid adenomas is described and the differentiation between parathyroid and thyroid adenomas outlined. An overall diagnostic accuracy of 75 per cent was achieved. The indications for parathyroid angiography are discussed.

The differentiation of primary hyperparathyroidism from the hypercalcemia of malignancy

The presence of hypercalcemia in patients with known cancers may be due to the cancers themselves, or to co-existing primary hyperparathyroidism. The differentiation of primary hyperparathyroidism from the hypercalcemia of malignancy is important since the relief of distressing symptoms and prevention of hypercalcemic crises and renal failure can be accomplished relatively easily by parathyroid surgery in the former condition, and only with difficulty, at times, with fluids and drugs in the latter condition. The histories of three recent patients are presented, which demonstrate the difficulties inherent in the differentiation of these conditions. These patients were ultimately found at operation to have primary hyperparathyroidism in addition to malignancies of the cervix, adrenal gland and kidney. In our experience the following have been helpful in establishing a diagnosis; history of hypercalcemia prior to development of cancer, the type of cancer itself, the effect of cancer therapy on the hypercalcemia, and selective venous sampling with radioimmunoassay for parathyroid hormone.