Increased Renal Parenchymal Retention of 99mTc-MDP (Hot Kidneys) in Two Patient of Hepatocellular cancer: One with and other without Osseous Metastases

Abstract

Background: Hepatocellular cancer (HCC) is the fifth-leading cancer in men worldwide. Here we present two HCC patients who showed high diffuse renal parenchymal retention of 99mTc MDP on bone scan. Cases presentation: Bone scan with 99mTc MDP was performed in two known HCC patients, which showed skeletal metastases in one and absent in other case. Their kidneys showed high renal parenchymal retention of tracer with kidneys looking much HOT than adjacent bones. The differential diagnosis of hot kidneys include nephrocalcinosis, hypercalcemia, hyperparathyroidism, chemotherapy, sickle cell disease, acute renal injury, recent radiotherapy and aluminum breakthrough of 99Mo-99mTc generator. Our patients did not fit in any of these. Hot kidneys in patient with liver cirrhosis have been reported due to hepatorenal syndrome. Although chronic liver parenchymal disease was present in the background of HCC, but our patients were not having hepatorenal syndrome (normal renal function tests). Quality control of generator and MDP vials used showed absence of any aluminum breakthrough and labeling efficiency was greater than 95% respectively. So, the exact cause of hot kidneys in these cases cannot be ascertained and some altered metabolism in liver and hemodynamic changes in body due to HCC might be the cause. Conclusion: High diffuse renal parenchymal retention of 99mTc MDP might be seen on bone scan in HCC cases. Its clinical significance is unknown and needs further research to find out its exact mechanism and cause.