Previously the major concern for needle biopsy was seeding and spreading of the tumor.
Only 2 cases since 1991 have been reported in the literature, indicating that the procedure is safe and underutilized.
Tumor seeding incidence less than 0.01% with renal biospy.
The likelihood of tumor spread via biopsy is no more than with other malignancies where such management is standard.
With transitional cancer there is a potentially higher risk of tumor spread and biopsy should not be performed for infiltrative central renal masses when transitinal carcinoma is expected.
Biopsy of small renal lesions allows for increased application of nephron sparing approaches.
Only 6% of patients have renal biopsies for small renal masses.
About 94% of patients with small renal cortical masses should have renal biopsy.
Renal biospy will yield diagnostic material in 80% of cases, and 20% of patients will require a second biopsy.
Renal biopsy will increase as the need for evaluating the molecular biology of a lesion is increasing.
Biopsy should not be performed if results of the test would not impact decision making.
Recommendations off for acquiring biopsy material of 10 mm in length and performing two whole needle cores biopsies for tumor.
Significant complications are rare, and minor complications are less than 5% (Lane BR et al).
In recent studies 5% of biopsies have insufficient material for diagnosis.
Presently, there is a 90% success rate in diagnosing small renal cortical tumors with percutaneous renal biopsy.
Preoperative needle core biopsy of lesions less than 5 cm revealed 25% benign lesions, despite such lesions considered likely malignant by radiographic analysis (Shannon BA et al):this suggests a high proportion of benign lesions justifies preoperative histological diagnosis to decrease the rate of unnecessary kidney surgery.