[Bone marrow changes in patients with thyroid carcinoma]

In 62 patients with thyroid carcinoma 79 MRI bone marrow examinations and 48 bone marrow scintigraphies were recorded before or following radioiodine therapy, to study the extent of bone marrow expansion. The results of both methods were the same. In 34/79 investigations normal findings were seen, in 18 the bone marrow expanded to the middle third and in 26 to the distal third of the femur. One patient showed bone marrow expansion to the tibia. These results were compared with the following data: histology of tumor, TNM-staging, time passed since thyroidectomy, accumulated doses of radioiodine therapy, results of 131I scintigraphy, hematological changes, thyroglobulin level, age and sex. No significant correlations were found between these and the bone marrow imaging results. Bone marrow changes in patients before radioiodine therapy were similar to those in patients treated with up to 48 GBq 131I. Blind biopsy of the posterior iliac crest in five patients showed slightly pathological reactive changes. In only 2/17 follow-up studies an increase of bone marrow expansion was seen. In 8 patients localized findings indicating malignant infiltration were observed. In 4/8 patients metastases of thyroid carcinoma were known or confirmed by pathological radioiodine uptake and in 2/8 metastatic involvement was assumed because of an increased thyroglobulin level.