 I'll be talking about partial nephrectomy for larger renal masses. And while I'll discuss the relevant literature, I think it's important to note that as we push the envelope and challenge the paradigm for how we best manage these patients, I'll share with you a couple cases that I think exemplify how this can both be a success and how it can also lead to failure. So this is a 67-year-old patient of mine who presented initially with a perinephric bleed and a renal mass you can see there on the right. A month later she presented to the Mayo Clinic specifically wanting a partial nephrectomy. She had stage three chronic kidney disease. So we re-imaged her with an MRI and the perinephric bleed resolved. She had a relatively straightforward partial nephrectomy. So I did this open under cold ischemia, 8 centimeters, T2, clear cell, grade three, no dissection at the same time, negative margins. Three months later she returns to see me. And she has, this is her IVC here, this is Bland thrombus, she's got tumor thrombus here, this is the proximal extent near the right hepatic vein takeoff. It was also into the left renal vein and talk about a bummer. So I took her back to the OR, we took this out, this is no longer a nephron sparing approach, took her kidney out as well. The kidney was actually negative, all the tumor was in her thrombus and she's currently NED, but went through this unfortunately. So just quickly, guidelines on T1B renal masses, a healthy patient standard is radical nephrectomy, another standard is partial nephrectomy. For the unhealthy patient, the standard is radical nephrectomy and recommendations, if that's not appropriate, are for partial or active surveillance. These are the EAU guidelines this year and I'll just point out that they state for a solitary tumor up to seven centimeters, nephron sparing surgery is the standard whenever technically feasible. This is a collaborative review in European neurology where they state similar findings that it partial nephrectomy is established treatment for T1A tumors and an emerging standard for T1B tumors, but that the choice should be individualized. So why do we consider partial nephrectomy in these larger tumors? This is from Igor Frank looking at or chance of benign versus malignant and low grade versus high grade based on tumor size. And you can see that for tumors between four and seven centimeters, the chance of it being benign is still around 10 percent and the chances of it being low grade even if malignant is still around two thirds to three quarters. We duplicated this study at Memorial Sloan Kettering and essentially found identical results with an identical number of patients. Brad Lipovich was the first to publish on partial nephrectomy comparing to radical nephrectomy for tumors four to seven centimeters. This has been duplicated multiple times including the group at Memorial and when I was a fellow at Memorial we combined these two databases, 1159 patients, T1B tumors, so four to seven centimeters who underwent partial radical nephrectomy and conducted outcome analyses. Predictors of cancer specific survival and a multivariable analysis are depicted here. I'll just point out that type of surgery, partial versus radical, was not significantly associated with cancer specific survival. We found no difference in overall survival when comparing these two treatment approaches. We found no difference of the two treatment approaches on overall survival and a multivariable analysis and thus we concluded that for T1B tumors four to seven centimeters, overall survival was similar, partial versus radical, cancer specific survival was not compromised when using partial nephrectomy and thus we felt these results supported the use of partial nephrectomy for select patients for renal tumors four to seven centimeters. Chris Waite looked at the Cleveland Clinic experience also comparing T1B renal masses four to seven centimeters, 1,000 patients, partial versus radical nephrectomy. They did a propensity scoring model to reduce the selection bias that is inherently present, but a little over half the patients in this series underwent partial nephrectomy. This is predictors of cancer specific survival and again I'll just point out that there was no significant difference partial versus radical nephrectomy in their multivariable analysis. They did see an improvement in overall survival among those treated with partial nephrectomy compared to radical nephrectomy. This persisted in their propensity scoring model in a single predicting variable which is depicted here, but when they included multiple predicting variables, treatment type, partial versus radical, was no longer associated with overall survival. However, postoperative renal function and T stage was. And this is showing the postoperative renal function. So these patients who presumably had surgically induced chronic kidney disease, as you can see as their GFR went down, this being stage four chronic kidney disease here, both overall survival and cancer specific survival was diminished. Cleveland Clinic also looked at their laparoscopic experience, tumors greater than four centimeters, 35 lap partial patients, 75 lap radical patients. And similar to what I've shown you before, recurrence free survival, cancer specific survival, overall survival, all of them were similar for these patients who were selected for partial nephrectomy done laparoscopically. This has also been looked at using the CR registry. I'll just show you two. There are multiple out there. These are the two most recent, but amongst almost 13,000 patients, no difference in overall survival, partial versus radical nephrectomy for T1B renal tumors. This is the latest one published this year. This is a cumulative incidence curve, but you can see no difference in terms of survival. What I also showing here is this is the incidence of use of partial nephrectomy for tumors four to seven centimeters. And you can see prior to 2000, it was rarely used. And as of 2008, partial nephrectomy in CR data was utilized 16% of the time. This is a little bit different than what we see at academic centers at Memorial Sloan Kettering. These are looking at percentage of patients treated with partial nephrectomy for four to seven centimeter tumors, 20% in the year 2000, and this steadily increased to 60% in the year 2007. So I'll briefly touch on T2 tumors or greater partial versus radical nephrectomy. This is from Fox Chase. This summarizes the available evidence. You can see that there's not very many studies. None of these studies have triple digit patients. Some of them are even multi-institutional. So there's not much out there. Certainly nothing randomized or prospective. This is the largest study looking at these larger, greater than seven centimeter tumors comparing partial nephrectomy to radical nephrectomy. There were 69 patients T2 or above. They were matched three to one to radical nephrectomy patients at the Mayo Clinic and outcome analyses were conducted. And similar to what we saw with the four to seven centimeter tumors, the red line is partial here. Metastas free probability, local disease recurrence, cancer specific survival, and overall survival were all similar when comparing radical nephrectomy to these patients who were selected for partial nephrectomy. Interestingly, also in this study, Rodney Bro looked at complications and the complication rates are higher when you do partial nephrectomy in these larger renal tumors. It was 17% for the partial nephrectomy in this group and obviously zero for the radical nephrectomy patients. So just back to the case example, here's a 46-year-old gentleman who presented my clinic with this 29 centimeter renal mass. Unfortunately, he had donated his right kidney as a living related transplant a few years prior to this. So this is a problem. We took him to the OR, I took him to the OR, and we removed this and a little bit of the kidney and the capsule of the kidney and ended up being a sarcoma, but he's now five years out NED. So I think this is an example of a success for nephron sparing surgery for these larger renal tumors. So in conclusions, for T1B T2 renal masses, for select patients, partial nephrectomy appears oncologically safe. The benefits of preserved renal function should be balanced with the higher risks of perioperative complication. Based on the literature to date, there's probably no survival benefit in partial versus radical nephrectomy for these larger renal tumors. And maybe Dr. Campbell will touch on this as well, but obviously a randomized trial is needed because everything I've presented was retrospective based. So thank you very much.