Contemporary clinical epidemiology of renal cell carcinoma: insight from a population based case-control study

To clarify the contemporary clinical epidemiology of renal cell carcinoma we present trends in clinical presentation and treatment in patients enrolled in a population based case-control study.

The National Cancer Institute performed a population based case-control study in metropolitan Detroit and Chicago from 2002 through 2007. In 1,136 patients with renal cell carcinoma who consented to an epidemiological interview and medical record review we ascertained detailed information on social and medical history, methods of renal cell carcinoma detection and diagnosis, cancer severity and treatment(s) received. From these data we assessed the demographic and cancer specific characteristics of study cases, and trends in clinical presentation, diagnosis and treatment.

Most patients with renal cell carcinoma had localized or regional tumors, including 52% with tumors 4 cm or less. The proportion of asymptomatic cases increased from 35% in 2002 to 50% in 2007 (p<0.001). Hypertension and diabetes were common in patients (58% and 17%, respectively) and 24% had at least 2 significant comorbid conditions at cancer diagnosis. While the use of laparoscopic surgery increased with time (p<0.001), fewer than 1/5 patients underwent nephron sparing surgery.

The proportion of patients presenting with small, asymptomatic renal cell carcinoma continues to increase. Most of these cases are still treated with radical nephrectomy, although increasingly via a laparoscopic approach. Since most patients with small renal cell carcinomas have 1 or more renal function relevant comorbidities, there is an imperative to increase the use of nephron sparing surgery.