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 impoant staging factor for this patient?

Commonly used criteria include (TNM staging):- Tumor size Extent of local growth Presence of lymph node metastases Presence of distant metastases. Renal cell carcinoma (TNM staging) (7th edition) T (Tumour) T1 T1a:tumour confined to kidney, <4 cm T1b: tumour confined to kidney,>4 cm but <7 cm T2:limited to kidney >7 cm T2a:tumour confined to kidney,>7 cm but not >10 cm T2b:tumour confined to kidney,>10 cm T3:tumour extension into major veins or perinephric tissues, but not into ipsilateral adrenal gland or beyond T3a:tumour grossly extends into the renal vein or its segmental (muscle-containing) branches, or tumour invades perirenal and/or renal sinus fat but not beyond the Gerota fascia T3b:spread to infra diaphragmatic IVC T3c:spread to supra diaphragmatic IVC or invades the wall of the IVC T4:involves ipsilateral adrenal gland or invades beyond N (Node) N0:no nodal involvement N1:metastatic involvement of regional lymph node(s) M (Metstasis) M0:no distant metastases M1:distant metastases Stage groupings stage I:T1 N0 M0 stage II:T2 N0 M0 stage III:T3 or N1 with M0 stage IV:T4 or M1 Notes the distinction between N1 and N2 was discontinued in the most recent version of staging contiguous involvement of the ipsilateral adrenal gland is T4, noncontiguous involvement is M1 the most common sites of metastasis are, in order: the lungs, the bones, lymph nodes, the liver, adrenals and the brain.