Epidemiology of the Small Renal Mass and the Treatment Disconnect Phenomenon

Abstract

The incidence of kidney cancer has steadily increased over recent decades, with most new cases now found when lesions are asymptomatic and small. This downward stage migration relates to the increasing use of abdominal imaging. Three public health epidemics-smoking, hypertension, and obesity-also play roles in the increase. Treatment mirrors the rise in incidence, with increasing interest in nephron-sparing therapies. Despite earlier detection and increasing treatment, the mortality rate has not decreased. This treatment disconnect phenomenon highlights the need to decrease unnecessary treatment of indolent tumors and address modifiable risk factors to reduce incidence and mortality.

Keywords: Epidemiology; Incidence; Kidney cancer; Mortality; Treatment disconnect.

Figure 1

Overall age-adjusted incidence rates of kidney cancer [A] and stratified according to disease stage [B], Surveillance, Epidemiology, and End Results, 1975–2009. From Gandaglia G, Ravi P, Abdollah F, et al. Contemporary incidence and mortality rates of kidney cancer in the United States. Canadian Urological Association Journal 2014;8(7–8):247–52; with permission.

Figure 2

Age-adjusted [A] overall and [B] kidney cancer-specific mortality (# of deaths per 100,000) by tumor size shows attenuation of mortality rates when accounting for missing data [C and D]. From Smaldone MC, Egleston B, Hollingsworth JM, et al. Understanding treatment disconnect and mortality trends in renal cell carcinoma using tumor registry data. Med Care 2016 [Epub ahead of print]; with permission.