Current Comment

METASTASES FROM THYROID TUMORS  When malignant thyroid tumors metastasize in distant and unexpected locations, the cells of the primary tumor have usually invaded the blood vessels and have thus been disseminated in the blood stream. In a study of 124 cases of metastatic lesions, Dinsmore and Hicken¹ found that (except for the cervical lymph nodes) the most common site of metastases was the lungs, and next the bones. The theory that the development of the transported cells into large metastatic tumors depends on a correct affinity between the cancer cells and the organ where they lodge would seem to explain the tendency of epithelial tumors of the thyroid to metastasize to bones. It is evident that metastases occur more frequently where the red bone is found, in the skull, vertebrae, pelvic bones, ribs and the proximal end of the humerus and femur. The highly nutritive bone marrow may encourage