During a routine checkup, a 50-year-old man is found to have blood in his urine. He is otherwise in excellent health. An abdominal CT scan reveals a 2-cm right renal mass. You inform the patient that staging of this tumor is key to selecting treatment and evaluating prognosis. Which of the following is the most important staging factor for this patient?

The choice of surgical approach or treatment modalities is influenced more by the stage of a cancer than by its cytologic grade. The significant criteria used for staging vary with different organs. Commonly used criteria include (1) tumor size, (2) extent of local growth, (3) presence of lymph node metastases, and (4) presence of distant metastases. The other choices reflect grade of the tumor.Diagnosis: Renal cell carcinoma