Abstract

Background: Hot kidneys had been reported on bone scan in few patients with hepatocellular carcinoma (HCC), but their cause is unknown. This study was conducted to compare the 99mTc-MDP renal parenchymal retention on bone scan in HCC patients with normal controls and chronic liver disease (CLD) patients and to correlate it in HCC patients with glomerular filtration rate (GFR).
Methods: Fifteen normal, 15 CLD, and 85 HCC patients with normal serum urea and creatinine underwent bone scan. Renal parenchymal retention index (PRI) in terms of the kidney-to-lumbar vertebrae counts ratio was calculated, and its mean was compared between these three groups by using Student's t-test. Last consecutive 25 HCC patients underwent 99mTc DTPA dynamic renal scan, and mean PRI in patients with normal GFR (group I, n = 6) was compared with those with deranged GFR (group II, n = 19).
Results: Mean PRI was 26.8% higher in CLD patients than control group (p = 0.000). Mean PRI in HCC group was 99.7% higher than control (p = 0.000) and 59.6% higher than that of CLD group (p = 0.004). GFR was deranged in 76% of HCC patients. Mean PRI was 36.9% higher in group II than group I at p = 0.023.
Conclusion: Renal parenchymal retention on bone scan is significantly higher in HCC patients than normal control and CLD patients. In HCC patients, it was significantly higher in patients with reduced GFR than those with normal GFR.

Key words: Hot kidney, renal parenchymal retention of MDP, hepatocellular CA, HCC, renal parenchymal retention index