How Is Technetium Used in the Diagnosis of Metastatic Deposits

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The Answer is The procedure starts with a molecule called methylene diphosphonate (MDP), which has a biochemical behaviour similar to the Ca⁺² ion: it is collected and metabolized by the internal structure of healthy bone. Regions with active bone growth will have increased uptake of Ca⁺², and hence MDP. The MDP molecule is labelled with Tc-99m and administered to the patient intravenously. It takes about 3 hours after administration for the Tc-99m-MDP molecule to be properly deposited in the skeleton, and imaging is performed typically at this time.
RAT: Certain types of cancers, such as those of the breast and prostate, have an unfortunate tendency to spread quickly to distant organs, predominantly the bones. Such spread is called metastasis and is typically associated with terminal disease, which can be treated but not cured. Metastatic deposits in bone are associated with rapid but abnormal bone growth that can be detected easily with a bone scan weeks or months before they can be detected with conventional radiological methods such as radiographs or computed tomography. This early detection capability occurs because, in disease, physiological changes precede structural anatomic changes by weeks or months. When an early diagnosis of metastasis is made, appropriate treatment can be initiated earlier, which may be associated with longer and better quality survival.

How Is Technetium Used in the Diagnosis of Metastatic Deposits

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