Pathological tumour diameter predicts risk of conventional subtype in small renal cortical tumours.
OBJECTIVE
To examine whether pathological tumour diameter assists in predicting conventional vs other histological subtypes in renal cortical tumours (RCTs) of <or=4 cm diameter.


METHODS
In all, 393 patients from Columbia University's Comprehensive Urologic Oncology Database who underwent radical or partial nephrectomy between 1988 and 2005 and had RCTs of <or=4 cm were analysed. Logistic regression analysis using tumour diameter as a continuous variable was used to determine whether size predicted histological subtype. Odds ratios (ORs) were calculated to estimate the likelihood of having conventional histology based on diameter.


RESULTS
The median patient age at surgery was 64.3 years and median tumour diameter was 3 cm, In all, 256 (65.1%) of the RCTs were conventional subtype and 137 (34.9%) were nonconventional. Logistic regression analysis showed that for every 1 cm increase in diameter up to 4 cm, the RCT was 1.27 times more likely to be conventional (P = 0.020). The ORs showed that a 4-cm RCT was 2.06 times more likely to be conventional than tumours of 0.6-1.5 cm.


CONCLUSIONS
There was a positive association between RCT diameter and the risk of having conventional renal cell carcinoma (RCC). Given that RCC histological subtype is a prognostic indicator for outcome, these findings may be applied in the selection of treatment options. Further studies investigating tumour size and other variables predictive of tumour histology will help clinicians better predict the RCC subtype.
Laudano
Melissa A
MA
Department of Urology, Columbia University Medical Center, New York 10032, USA. mal2117@columbia.edu
Klafter
Farrah E
FE
Katz
Mark
M
McCann
Tara R
TR
Desai
Manisha
M
Benson
Mitchell C
MC
McKiernan
James M
JM
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002292:Carcinoma, Renal Cell / Q000473:pathology* / Q000601:surgery; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007672:Kidney Cortex / Q000473:pathology* / Q000601:surgery; D007680:Kidney Neoplasms / Q000473:pathology* / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D009392:Nephrectomy / Q000379:methods*; D011379:Prognosis; D012044:Regression Analysis; D012307:Risk Factors; D055815:Young Adult