A case controlled study of acquired risk factors for renal cell carcinoma in a south Asian cohort – is it similar to the west?

Objective: To identify the validity of established western risk factors in renal cell
carcinoma in Sri Lanka.
Design, setting and methods: A case control study was designed to compare 36
consecutive, renal cell carcinoma (RCC) cases treated at one urology unit of a tertiary
referral centre with 72 age, sex matched controls. Well studied risk factors in western
countries such as smoking, hypertension, obesity, occupational chemical exposure
and use of long term analgesics were included. Data was analyzed with standard
matched pair methods. Conditional logistic regression models were used to examine
the univariate and multivariate relationships of RCC with various risk factors.
Results: There were 28 males and 08 females. Mean age at diagnosis was 56.92
(27-83) years.
Obesity (BMI ≥ 30 kg/m2) increased the risk of RCC by 6 folds in comparison to BMI
less than 25. Positive occupational exposure was shown to increase the risk of RCC
by 3.2 folds (CI = 1.2-8.5) and hypertension by 4.1 folds (95%CI 1.09 - 15.39) after
making adjustments for co-founding factors. Interestingly amount of smoking calculated
in pack years showed an increasing trend in the odds ratio suggesting increase risk of
RCC with smoking, but failed to show a strong association in the univariate analysis.
Conclusions: Comparing to the results of western studies present smoking state didn't
show a strong positive correlation as a risk factor. However, increasing pack years
demonstrated an increased risk. Hypertension, obesity and occupational chemical
exposure were shown to increase the risk as found in the west. Other factors such as
analgesics, alcohol and social class did not demonstrate a significant correlation.

DOI: 10.4038/sljs.v27i2.2098

The Sri Lanka Journal of Surgery 2009: 27: 39-44