A decade of surgically removed small renal masses in the Netherlands: characteristics and trends in type of surgery and pathologic reporting.
OBJECTIVE
To assess nationwide the pathologic characteristics and trends in type of surgery and pathologic reporting in surgically managed renal tumors ≤ 4 cm.


METHODS
A review of all pathologic reports of primary small renal masses operated on in the Netherlands during the period 1995 to 2005 was performed. The data source was a nationwide central archive of histocytopathology (Patologisch Anatomisch Landelijk Geautomatiseerde Archief). Tumors were stratified into three groups: ≤ 2, 2.1 to 3.0, and 3.1 to 4.0 cm. Age, sex, type of operation, and tumor pathology were analyzed. For renal-cell carcinomas, grade (3-tiers Fuhrman) and stage (2002 Tumor, Node, Metastasis) were assessed. Trends in type of surgery (radical or partial nephrectomy [PN]) and pathologic reporting during the study period were analyzed.


RESULTS
Of all operated primary kidney tumors, 25.3% were ≤ 4.0 cm. The mean age of the patients was 63.1 years (standard deviation 11.7), and the male/female ratio was 3:2. Only 7.5% were benign tumors, and 9.8% were locally advanced (≥ T₃). Tumors ≤ 3.0 cm were more likely to be benign (P = 0.006) and of lower stage (P ≤ 0.001) than tumors of 3.1 to 4 cm. PN was performed in 16.5% of the cases. Grade and subtype were reported in 55% of the cases. The rate of PNs performed increased during the decade. There was a trend in increased reporting of grade and subtype.


CONCLUSIONS
A quarter of all the operated primary kidney tumors were ≤ 4 cm. Smaller tumors were more likely to be benign and of lower stage. A cutoff size regarding biologic aggressiveness can be settled at the 3 cm size. The PN rate increased along the decade. Grade and subtype reporting rates remained suboptimal, although a positive trend was noted.
Kümmerlin
Intan P E D
IP
Department of Urology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
ten Kate
Fiebo J W
FJ
Wijkstra
Hessel
H
Zwinderman
Aelko
A
de la Rosette
Jean J M C H
JJ
Laguna
M Pilar
MP
D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000473:pathology* / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009392:Nephrectomy / Q000379:methods* / Q000639:trends; D009426:Netherlands; D011446:Prospective Studies; D013997:Time Factors