After partial nephrectomy, kidney function decreases by about 10% overall and by about 20% in the operated kidney. This is primarily due to the loss of healthy parenchymal volume during resection of the tumor. In an effort to preserve and regenerate healthy parenchyma during the procedure and ultimately renal function after partial nephrectomy, the single center double arm single-blinded randomized screening clinical trial will evaluate the ability of human amnion/chorion allograft to facilitate the recovery of renal function following robotic partial nephrectomy.

To determine whether Amniofix facilitates improved recovery of renal function at 12 months.

Inclusion Criteria:

• Any individual with a diagnosis of a renal mass.
• All Patients undergoing partial nephrectomy as their definitive treatment for their renal mass.
• Ability to understand and the willingness to sign a written informed consent.
• Patients with a solitary clinical T1a renal mass.

Exclusion Criteria:

• Patients undergoing radical nephrectomy as their definitive treatment for their renal mass.
• Patients with Transitional Cell Carcinoma.
• Patients with known hereditary syndromes such Von Hippel-Lindau (VHL) syndrome, Lynch Syndrome, Birt-Hogg-Dube Syndrome.
• Patients with metastatic disease undergoing cytoreductive nephrectomy as their definitive treatment for metastatic disease.
• Patients with prior kidney surgery.
• Patients with a solitary or horseshoe kidney.
• Patients with a positive margin found during intra-operative frozen section done only when clinically indicated (i.e., macroscopic abnormality identified).
• Patients with multiple renal masses.
• Patients with greater than a clinical T1a renal mass.