Diagnostic Value of Tc-99mMDP Bone Scan in Assessment of Renal Functions in Cancer Patients Compared to Estimated Glomerular Filtration Rate.

* Bone scan is one of the frequently used imaging tests in nuclear medicine. It is applied as a test for some oncologic and non-oncologic diseases; the common use is for the detection of bone metastasis from malignant tumors. Renal function may worsen with increasing age, co-morbidities like diabetes, hypertension, acute loss of weight and muscle mass, dehydration and long term use of non-steroidal inflammatory drugs and after some malignancies like multiple myeloma. Therefore renal function assessment is important and can be done by glomerular filtration rate using dGFR. Such a method uses technetium-99m-diethyl-triamine-penta-acetic acid (99mTc-DTPA). Other methods are SCR levels and estimated glomerular filtration rate (eGFR). The use of nephrotoxic drugs such as cisplatin is one of the chemotherapeutic agents in the treatment of a variety of solid tumors; however, it has a side effect of nephrotoxicity. In addition, methotrexate is primarily excreted by the kidneys and estimate of renal function is essential before the use of high-dose therapy. * Glomerular filtration rate indicates creatinine clearance (CrCl), i.e., a ratio of the concentration of creatinine in serum and urine. Serum creatinine and CrCl have the leading role in the early diagnosis, monitoring and classification of chronic renal insufficiency. MDRD equation may be used for the estimation of glomerular filtration rate, which is accepted due to its simplicity, economic viability and acceptable performance. The most commonly used formula is the "4-varibale MDRD," which estimates GFR using four variables: Serum creatinine, age, race and gender. * Information about the kidneys can be obtained from bone scan because Tc-99mMDP is excreted through the kidneys. 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. * The study aims to investigate the use of Tc-99mMDP for assessing glomerular filtration rate to assess metastatic work up and renal function at a single Tc-99mMDP study, thereby reducing cost, time and radiation exposure.