What is the primary use of I-131 in medical practice?

I-131, or iodine-131, is primarily used in medical practice for the treatment of thyroid cancer. This radioactive isotope is taken up preferentially by thyroid tissue, including cancerous cells. When administered therapeutically, I-131 emits beta radiation that destroys thyroid cancer cells while minimizing damage to surrounding healthy tissues. This targeted approach makes it a highly effective treatment modality for both differentiated thyroid cancer and hyperthyroidism.

The use of I-131 for thyroid cancer is well-established, and it plays a crucial role in both the treatment of this condition and the management of thyroid cancer recurrence. It is often used following thyroidectomy (surgical removal of the thyroid gland) to eliminate any remaining cancerous cells or to treat metastatic disease.

In contrast, other options such as bone pain palliation, clinical imaging, and bone marrow suppression do not represent the primary application of I-131. While other isotopes might be employed for imaging or palliation in the context of bone-related diseases, I-131's specific affinity for the thyroid gland makes it an indispensable tool in managing thyroid cancer.