Kidney Cancer Journal 107
thors noted that some biomarker levels are affected by
blood contamination during resection, as well as induction
of anesthesia per se. These results are important to
account for confounders in future studies looking at the
correlation of urinary biomarkers with surgical and renal
functional parameters.
Pruthi et al (Poster #50) performed a radiogenomic study
correlating image “roughness” as calculated from CT
scans, with miR expression in 19 patients with clear cell,
chromophobe and papillary RCC. They found that miR-
10a, miR-10b, and miR-100 levels were inversely correlated
with image roughness, while miR-21/miR-10b ratio
was positively correlated with image roughness and could
potentially differentiate RCC subtype.
Desai et al (Poster #157) studied the role of preoperative
MRI in characterizing the tumor-parenchyma interface in
43 patients with a small renal mass who underwent robotic
partial nephrectomy. All tumors had a visible
pseudocapsule on MRI. 76.7% of the described pseudocapsules
were circumferential, while 18.6% were fragmented
and 4.7% were invasive. A pseudocapsule was
identified in all tumor specimens on histologic evaluation.
The authors noted that the presence of a fragmented
or invasive pseudocapsule on preoperative MRI was associated
with a higher i-Cap score.
Outcomes Research
Non-metastatic
ACTIVE SURVEILLANCE
Petros et al (Poster #39) studied conditional survival a
cohort of 272 patients enrolled in a prospective active surveillance
protocol for small renal mass. They noted that
patients who reached the 2-year landmark had an improved
likelihood of survival to 5 years. Multivariable
analysis revealed that eGFR, Charlson Comorbidity
Index, and tumor size of 3-4 cm were predictive of overall
survival at baseline and at the 2-year landmark. Interestingly,
patients with tumor size of 3-4 cm were at a
higher risk of non-RCC death.
Pruthi et al (Poster #49) reviewed the outcomes of active
surveillance of 106 patients with 140 renal cystic lesions
deemed to be Bosniak 2F or higher. Patients had a
median follow up of 46 months, with a median of 7 abdominal
scans performed. Bosniak 3 cysts were divided
into 3s (enhancing septation) and 3n (nodularity present).
The authors found that Bosniak 3s were more likely
to regress, Bosniak 3n were more likely to progress, with
no difference in growth rates between Bosniak 4 and non-
Bosniak 4 cysts, and no development of metastatic disease
in any of the patients on surveillance.
PATHOLOGY
Westerman et al (Poster #42) used a large RCC cohort
to study 158 patients with cystic clear cell RCC. These patients
were noted to be younger, have more cystic features
on imaging, did not present with metastatic disease, and
had no sarcomatoid dedifferentiation and only 1% rate
of coagulative tumor necrosis, when compared with noncystic
RCC. Only 1 of the 158 patients with cystic RCC
died of RCC (median follow up of survivors was 10.5
years), highlighting the favorable prognosis of this group
of patients.
Bhindi et al (Poster #54) characterized a large cohort of
patients with RCC treated with surgery into indolent versus
aggressive, instead of the more commonly used terminology
of benign versus malignant. Indolent tumors
consisted of low-grade clear cell RCC, low-grade papillary
RCC, low-grade translocation-associated RCC, any chromophobe,
clear cell papillary, mucinous tubular and spindle
cell, tubulocystic, and SDH-B deficient RCC. The
authors noted that the 10-year CSS of patients with indolent
malignant tumors was 96%, compared to 82% for
those with aggressive tumors. In addition, they calculated
the risk of malignancy and aggressiveness based on tumor
size and sex. They noted that with increasing tumor size,
the probability of malignancy reaches 90% at around
4cm, and plateaus afterwards, while the risk of aggressiveness
continues to increase with larger tumor sizes. Not
surprisingly, for any particular size, the risk of aggressive
histology was higher in males than in females.
Hamilton et al (Poster #37) used a multi-institutional
cohort of 2640 patients with non-metastatic RCC to analyze
the nuances in staging pT3a patients. They noted
that those patients who were considered cT1 and were
upstaged at surgery to pT3a had similar outcomes to patients
with pT2 disease, and those patients with cT2 upstaged
to pT3a were more in line with cT3a upstaged to
pT3a. The authors are suggesting a modification to the
TNM staging system based on these data, after appropriate
confirmatory studies are done.
Reddy et al (Poster #168) used a similar cohort of patients
to compare outcomes of patients who underwent
radical nephrectomy or partial nephrectomy, and were
upstaged at surgery to pT3a, and noted that patients who
underwent partial nephrectomy were at a higher risk of
positive surgical margin, lower risk of blood transfusion,
and lower risk of GFR<60. There were no differences in
complication rates or oncologic outcomes when comparing
upstaged pT3a patients who underwent radical
nephrectomy versus partial nephrectomy.
RENAL FUNCTION
Isharwal et al (Poster #148) studied the impact of preoperative
comorbidities on recovery of renal function
after partial nephrectomy using 405 patients from a single
institution. The authors showed that the primary determinant
of renal functional recovery was parenchymal
preservation, followed by ischemia characteristics (cold
versus warm, duration), and was independent of comorbidities.