We evaluated renal function before and after laparoscopic partial
nephrectomy by calculating differential renal function thru the use of renal scintigraphy
with 99mtecnetium-mercaptoacetyltriglysine (99mTc-MAG3).
Differential renal function was assessed for 62 patients undergoing laparoscopic partial
nephrectomy for renal tumors with renal scintigraphy before operation and six months
post operation.
Mean operating time, ischemic time, blood loss and tumor diameter were 142 min, 27
min, 75 ml and 2.0 cm, respectively. The mean reduced rates of calculating glomerular
filtration rate (cGFR) of a bilateral and the diseased-side kidney were 7.96% and
23.3%, respectively, and was statistical significant (p<0.001).
Meanwhile, the mean rate of increase of cGFR on the non-diseased-side kidney was
6.8%, which was significantly decreased (p=0.005). By univariate analysis, patients
with a tumor of more than 2 cm in size and with clamping of the renal artery for over
30 minutes had decreased 6-month postoperative cGFR by more than 20%.
In multivariate analysis, tumor size was the most significant factor related to a decrease
in cGFR. Patients with a tumor larger than 2 cm in size had a longer operation time
(p=0.0005) and a higher amount of bleeding (p=0.0012).
In comparison, the six-month postoperative cGFR of patients less than 55 years-old had
significantly increased cGFR over 20%.
Lower cGFR of the diseased-side kidney after partial nephrectomy was predicted by
longer ischemic interval and tumor size. Age predicted increasing cGFR of the nondiseased
side after partial nephrectomy. Currently, we are endeavoring to shorten
ischemic time. Younger patients with renal tumors should adapt to laparoscopic partial
nephrectomy.
Keywords: Laparoscopic nephrectomy, MAG3, Partial nephrectomy, Renal cell
carcinoma, Renal scintigraphy.
