A biopsy on a kidney tumor is often not possible because of bowel, & bones being in the way.

I had kidney removed in January of this year and no biopsy was done. I went to three specialists and they each said the same thing. Over 20% of biopsies done on kidneys say there is no cancer, when indeed it is cancer. When my kidney was evaluated after removal, pathology report found it was a non cancerous tumor of 4cm. Prior to surgery I had scans to see if cancer had spread. Every test was negative, however the treatment of choice was a total nephrectomy. We try to inform ourselves the best we can and make the best decision we can. Blessings.

No, I didn't have any risk factors for a malignancy, so I wasn't too concerned about that, but the doctor advised the surgery concluding, following the laparoscopies, that the mass was larger than the CT Urogram indicated and was taking up 1/3 of the kidney. As Amyb5 states below, there are reasons for not doing a biopsy before surgery. A think a concern with seeding, i.e.. spreading cancerous cells is another reason.