The value of Tc-99mMDP bone scan in assessment of renal functions in urinary tract neoplasm patients after chemotherapy compared to Tc-99mDTPA renal scan

Aim: our study investigates the use Tc-99mMDP for assessing GFR, split function and metastatic work-up in urinary tract neoplasm patients to replace separate Tc-99mDTPA and Tc-99mMDP studies with a single Tc-99mMDP study, thereby reducing cost, time and radiation exposure. Materials: Fifty adult patients with malignant urinary tract tumors underwent Tc-99mDTPA and Tc-99mMDP scans within one week. Tc-99mDTPA was administered at a 5 mCi for GFR measurement. For Tc-99mMDP, 5 mCi was used for dynamic renography followed by 15 mCi for post-3-hour whole-body imaging. Each kidney has its own ROI set around it, with a background area positioned underneath each kidney. The Gates' approach was used to calculate the GFR and split function. Results: the research showed a robust positive correlation between Tc-99mDTPA and Tc-99mMDP measurements: total GFR (r= 0.981, p < 0.001), LT kidney GFR, (r = 0.959, p < 0.001), RT kidney GFR (r = 0.980, p < 0.001), LT kidney split function (r = 0.951, p < 0.001) RT kidney split function (r = 0.951, p < 0.001). Conclusion: Tc-99mMDP can be an alternative to Tc-99mDTPA for evaluating renal function while conducting bone metastases surveys in patients with urinary tract malignancy with reduced cost and radiation exposure.