Renal tumors in young adults.

PURPOSE: The clinical and pathological features of solid or complex cystic renal masses in young adults have not been defined. We present our experience with patients 17 to 45 years old with such renal masses to define the incidence of malignant vs benign lesions, familial tendencies and clinical outcomes.

MATERIALS AND METHODS: The medical records of all patients 17 to 45 years old who presented with a solid or suspicious complex cystic renal mass at 2 tertiary care hospitals between 1988 and 2002 were retrospectively reviewed. Pertinent clinical information was compiled, including age, gender, mode of presentation, renal function, year and type of surgery, pathological analysis and survival data.

RESULTS: There were 114 evaluable patients who underwent a total of 119 nephrectomies. Mean patient age was 37.1 years and males comprised 56.1% of the population. Twelve patients had familial renal cell carcinoma (RCC), the von Hippel-Lindau syndrome. Mode of presentation for patients with sporadic disease was symptomatic (55.9%), incidental (35.3%) or unknown (8.8%). Radical nephrectomy, partial nephrectomy and nephroureterectomy were performed in 80 kidneys (67.2%), 37 (31.1%) and 2 (1.7%), respectively. Malignant lesions comprised 79.8% of all masses and 95.8% of these were renal cell carcinoma. Of the RCCs 75.8% were grade 1 or 2 and 89% were organ confined. Young women were much more likely than men to have a benign lesion (36.0% vs 9.5%, p <0.01) and the diversity of histologies was impressive (of the 24 total benign masses 9 were different tumor types). With an average followup of 38.3 months overall survival is 90.2%. Among patients with RCC 84.9% are alive and cancer-free, 11.6% are dead from disease and 3.5% are alive with recurrent disease.

CONCLUSIONS: We report the largest known series of solid or suspicious complex renal masses in young adults. As expected, familial tumors are more common in this population. While RCC is the most common tumor, a wide variety of potential pathological outcomes are possible, particularly in women, who were much more likely to have a benign lesion. RCC in this patient population appears to have a favorable prognosis, despite symptomatic presentation in the majority of cases.