The principle of radioactive drug treatment of bone metastasis

The action of radioactive drugs can help shrink the size of bone metastasis tumors, thereby reducing the pressure on the periosteum and helping to relieve the patient's pain.

The principle of using radiopharmaceuticals to treat bone metastasis in clinic is that, due to the high affinity between radiopharmaceuticals and bone tissue, bone metastasis lesions can absorb more radiopharmaceuticals than normal bone tissue because of the active metabolism of bone tissue, so that a large amount of radiopharmaceuticals can be accumulated in the local bone metastasis. Then, the radiopharmaceuticals emit beta rays to exert internal irradiation effect on the local tumor lesions. Through the biological effect of ionizing radiation, the capillaries in the lesions are dilated, the cells are edematous, the nuclei are condensed, inflammatory cells are infiltrated, and the tumor cell nuclear vacuoles are formed or disappeared, so that the tumor lesions are necrotic or fibrotic, thereby inhibiting, shrinking or clearing the tumor lesions to varying degrees.

The mechanism by which radioactive drugs relieve bone pain in the treatment of bone metastases may be related to the following factors.

① The β-particle radiation effect shrinks the lesion, reduces the pressure on the periosteum and bone marrow cavity, and reduces the compression of the tumor tissue on the nerves;

② Recalcification of eroded bone in bone metastasis foci;

③ Ionizing radiation affects the depolarization process of nerve endings and interferes with the conduction of pain signals;

④Inhibit the secretion of pain mediators such as bradykinin and prostaglandins.

In addition, the deposition of phosphonate compounds in the active area of ​​osteoblasts also plays a certain role in relieving pain.