Compensatory renal growth in children with unilateral renal tumor treated by nephron-sparing surgery or nephrectomy.
BACKGROUND
In children with an unilateral renal tumor, nephron-sparing surgery (NSS) results in a more adequate renal function adaptation compared to nephrectomy. In the present study, we investigated whether nephron-sparing surgery is followed by a different renal structure adaptation compared to nephrectomy.


METHODS
Sixteen patients with unilateral renal tumor treated by nephrectomy (Group 1) and 10 treated by nephron-sparing surgery (Group 2) were enrolled in the study. Kidney volume was estimated by ultrasonography, using the formula for a prolate ellipsoid. Kidney volume was adjusted to the patient's weight and kidney laterality and expressed as a percentage of the expected volume of two kidneys in a healthy child. Total kidney volume (TKV) corresponded to the volume of the contralateral kidney in Group 1 patients, and to the volume of contralateral kidney + kidney remnant in Group 2 patients. Renal function was evaluated by serum creatinine values adjusted for sex and age and expressed as standard deviation scores (SDS).


RESULTS
Group 2 patients presented with a greater indexed TKV compared to Group 1 patients, (97.4 +/- 18.8 % vs. 77.0 +/- 17.7 %; p = 0.005). Indexed TKV below the reference range for healthy controls with two kidneys was found in 4 of 10 Group 2 patients vs. 14 of 16 Group 1 patients (p = 0.017). In both patient groups, correlation analysis of indexed TKV and creatinine SDS showed a negative correlation (r = - 0.47; p = 0.01).


CONCLUSIONS
In children with unilateral renal tumor, NSS is followed by a more adequate compensatory restoration of TKV compared with nephrectomy.
Cozzi
F
F
Department of Pediatric Surgery Unit, University of Rome La Sapienza, Viale Regina Elena 324, Rome, Italy. francesco.cozzi@uniroma1.it
Zani
A
A
Schiavetti
A
A
Morini
F
F
Degaetano
V
V
Matrunola
M
M
Cozzi
D A
DA
D000222:Adaptation, Physiological / Q000502:physiology*; D002648:Child; D003430:Cross-Sectional Studies; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007668:Kidney / Q000254:growth & development*; D007680:Kidney Neoplasms / Q000473:pathology / Q000601:surgery*; D008297:Male; D009392:Nephrectomy / Q000379:methods*; D009929:Organ Size; D020127:Recovery of Function / Q000502:physiology*; D012189:Retrospective Studies; D016896:Treatment Outcome