Prospects of Remission in Medullary Thyroid Carcinoma According to Basal Calcitonin Level

Prediction of remission in medullary thyroid carcinoma (MTC) depends on histopathological information often unavailable before surgery. Simply requiring a venous blood sample, preoperative basal calcitonin levels may be a better indicator of remission. In this institutional series of 224 consecutive patients with MTC and elevated preoperative basal calcitonin levels, postoperative calcitonin levels normalized in 28 (62%) of 45 patients with node-negative MTC and in 18 (10%) of 177 patients with node-positive MTC. On multivariate analysis, preoperative basal calcitonin levels greater than 500 pg/ml best predicted the failure to achieve biochemical remission, followed by nodal metastasis and reoperative status. Cumulative rates of biochemical remission fell continuously with rising serum basal calcitonin in node-negative patients. Node-positive patients did not achieve biochemical remission when their preoperative basal calcitonin levels exceeded 3000 pg/ml. Nodal metastasis started emerging at basal calcitonin levels of 10–40 pg/ml (normal range,