CUA 2017: Medication Use and Kidney Cancer Risk: A Population-Based Study

Toronto, Ontario ( Exposure to commonly prescribed medications may be associated with reduced cancer risk; however, there is limited data in kidney cancer. Furthermore, methods of classifying cumulative medication exposure in previous studies may be prone to bias.

Dr. Madhur Nayan presented a population-based, case-control study using healthcare databases in Ontario, Canada through the Institute for Clinical Evaluative Sciences (ICES). Individuals enrolled as cases were aged ≥66 years with an incident diagnosis of kidney cancer. For each individual enrolled as a case, the authors identified up to four individuals as controls matched on age, sex, history of hypertension, comorbidity score, and geographic location. Cumulative exposure to commonly prescribed medications hypothesized to modulate cancer risk were obtained using prescription claims data. The authors modelled exposure in four different fashions: 

1) As continuous exposures using a) fractional polynomials (which allow for non-linear relationship between an exposure and outcome) 
 b) Assuming linear relationships

2) As dichotomous exposures denoting a) ≥3 vs. <3 years exposure 
b) ‘Ever’ vs. ‘never’ exposure. 

Finally, the authors used conditional logistic regression to estimate the association of medication exposure on incident kidney cancer. 

10,377 incident cases of kidney cancer and 35,939 matched controls were analyzed. When using fractional polynomials, increasing cumulative exposure to acetylsalicylic acid, selective serotonin reuptake inhibitors, and proton-pump inhibitors were associated with significantly reduced risk of kidney cancer, while increasing exposure to antihypertensive drugs was associated with significantly increased risk.

Dr. Madhur concluded his interesting presentation by stating that this study provides impetus to further explore the effect of commonly prescribed medications on carcinogenesis, to identify modifiable pharmacological interventions to reduce the risk of kidney cancer.

Presented By: Madhur Nayan, MD, University of Toronto, Toronto, Ontario,  Canada

Written By: Hanan Goldberg, MD, Urologic Oncology Fellow (SUO), University of Toronto, Princess Margaret Cancer Centre  Twitter: @GoldbergHanan at the  72nd Canadian Urological Association Annual Meeting - June 24 - 27, 2017 - Toronto, Ontario, Canada