What is the best way to cure a renal solid mass?

You remove it & find out what it is. You may need to remove the kidney as well. I biopsy might be done initially through a fine tube, but depending on the initial evaluation direct observation & removal may be considered the proper plan.

It depends on the size of the mass and patient's overall health (comorbidity). Most renal mass above 4 cm should be removed if patient is at low risk for surgery. Mass at 2-4 cm is a gray zone, patient and urologist can decide together, biopsy of the mass if possible. Mass less than 2 cm can be monitored with ultrasound because renal carcinoma (RCC) is a slow growth cancer.