Use of isotope bone scans and skeletal survey X-rays in the follow-up of patients with thyroid carcinoma.

We have evaluated the utility of isotope bone scans and skeletal survey X-rays in the periodic evaluation of patients known to have had thyroid carcinoma. Patient data were evaluated in 29 patients with known metastatic disease and 79 patients without known metastatic disease who were followed over a period of 3-12 years and who had coincident 131Iodide whole body scans, technetium pyrophosphate bone scans, chest X-rays, and skeletal surveys, at periodic intervals. The information gained for each patient, at a time when two or three of the major survey procedures were conducted coincidentally, was evaluated retrospectively for its impact on classification and management of the patients. Metastatic tumor was detected in most instances by 131I RAIU in the lungs or by chest X-rays. Six patients had proven bone metastasis. Four of these patients had positive 131Iodide RAIU in bones, and two were positive and two negative by pyrophosphate bone scan. Only one was positive by skeletal survey X-rays at the time metastases were first detected by bone scans. Nine of the patients with metastatic disease displayed abnormal bone scans, but six of these were determined to be false positives. Bone scans detected one poorly differentiated metastatic tumor which did not accumulate 131I. Bone scans were more sensitive than skeletal survey X-rays. Physical exam, chest X-ray, and I131 whole body scans detected all instances of metastatic carcinoma.(ABSTRACT TRUNCATED AT 250 WORDS)