ObjectiveTo investigate the reproducibility and interobserver agreement for R.E.N.A.L.
nephrometry scoring system.Materials and MethodsTwo independent radiologists retrospectively analyzed 46 consecutive patients
with renal masses, between 2008 and 2012, using the R.E.N.A.L. nephrometry
score (RENAL-NS), which is based on the evaluation of five anatomical
features of the tumor, as evaluated with computed tomography or magnetic
resonance imaging: Radius,
Exophytic/endophytic properties, Nearness
to the collecting system, Anterior or posterior descriptor,
and Location relative to the polar line. Tumor complexity
was graded as low, intermediate, or high. The interobserver agreement was
calculated for the total score and for the score for each parameter.
Surgical excision of the tumors was used as the standard of reference.ResultsThe interobserver agreement for each of the RENAL-NS parameters,
respectively, a hilar location, and the total score was 98%, 80%, 100%, 89%,
85%, 89%, and 93% of patients, corresponding to kappa values of 0.96, 0.65,
1.00, 0.75, 0.72, 0.78, and 0.88, respectively. The Nearness, Radius, and
total score showed the best agreement. For the cases that were discordant in
terms of the final score, no major implications in surgical planning were
observed.ConclusionThe RENAL-NS is a structured, useful system to assess the anatomical features
of renal tumors. It is easily applicable and reproducible, even for less
experienced radiologists.