Thompson, R. Houston

456 Background: Renal medullary carcinoma (RMC) is a rare, aggressive malignancy for which relatively limited characterization exists to date. We evaluated clinicopathologic features, treatment patterns, and variables associated with outcomes for patients with RMC. Methods: We reviewed the National Cancer Database to identify patients diagnosed with RMC between 1998-2012. Overall survival (OS) was estimated using the Kaplan-Meier method. Clinicopathologic features associated with all-cause mortality (ACM) were assessed using Cox regression analysis. Results: We identified 153 patients with RMC, comprising approximately 0.04% of renal malignancies during this time period. Median age at diagnosis for RMC was 24 years (IQR 20, 31). The majority of RMC patients were black (135; 88%), male (108; 71%), and presented with unilateral, right-sided tumors (101; 66%). Notably, nearly half (72; 48.9%) presented with metastatic disease. A total of 92 (64.3%) patients underwent radical nephrectomy (RN), and 2 (1.3%) were treated with partial nephrectomy. Pathologic stage at nephrectomy was ≤pT2 in 30 patients (32.6%), pT3 in 43 (46.7%), pT4 in 7 (7.6%), and N+ in 50 (55.6%). Of the patients who underwent RN, 60 (65.2%) received multimodal therapy (MMT), including radiation (3; 3.3%), systemic therapy (49; 53.3%), and radiation + systemic therapy (8; 8.7%). Of the 59 patients who did not undergo surgical resection, the majority (46; 77.8%) presented with M1 disease. Median OS was 7.8 months for the entire RMC cohort, with 1- and 3-year OS of 34% and 11%, respectively. Notably, median OS for patients presenting with M1 and M0 disease was 5.2 months versus 11.2 months, respectively (p< 0.01). On multivariable analysis, treatment with RN (HR 0.40; p=0.003) or RN+MMT (HR 0.44; p<0.001) were associated with decreased ACM, whereas the presence of metastatic disease at diagnosis remained associated with an increased risk of ACM (HR 1.74; p=0.02). Conclusions: The prognosis for patients with RMC is dismal, with a median OS under 8 months. Further studies, including the development of novel therapies, are needed to establish the optimal multimodal management approach for these patients.

433 Background: Current guidelines suggest that percutaneous thermal ablation (PTA) can be utilized in those with significant comorbidity who are unable to tolerate surgery (radical or partial nephrectomy). However, the use of PTA in healthy patients, who are otherwise candidates for surgery, has been limited. Here, we reviewed our institutional experience in healthy patients electing to undergo PTA, specifically cryoablation. Methods: We identified patients ≤65 years undergoing percutaneous cryoablation for solitary, non-metastatic renal masses <7cm (cT1). We further limited our cohort to patients with an ASA score of 1 or 2, and in whom pre-operative eGFR was >60. Clincopathologic characteristics and recurrence patterns (local recurrence within the kidney versus metastatic disease) were evaluated. Results: Between March 2003 and December 2015, 705 patients underwent cryoablation, of whom 43 (6.1%) were deemed to be “healthy”. Median age of this cohort was 57 years (IQR 52−62), with pre-ablation eGFR of 75.6 (IQR 69.0-86.3). Seven patients (16.3%) had a prior partial nephrectomy, and 5 (11.6%) had a solitary kidney. The majority (40, 93.0%) of ablated masses were cT1a, with 3 (7.0%) being cT1b. Median tumor size was 2.0 cm. 27 masses (63.7%) were biopsy-proven renal cell carcinoma (RCC) and 6 (13.6%) were benign; histology was unknown in 10 (22.7%). Follow-up imaging was available for 37 patients. Median radiological follow-up was 22 months (IQR 9-42), during which time 2 patients developed metastatic disease and 1 developed local recurrence; all events were in patients with biopsy-proven RCC. No patients died from RCC during this time period. Conclusions: In this single institution cohort of “healthier” patients with cT1 solitary renal masses, cryoablation offered reasonable short term oncologic control. While longer follow-up data are needed to evaluate for durability, cryoablation in healthy patients, particularly those with challenging surgical anatomy, warrants further study.

367 Background: While neoadjuvant chemotherapy (NAC) for muscle−invasive bladder cancer (MIBC) is recognized as the standard of care, the management of patients with locally advanced and/or nodal disease after NAC and radical cystectomy (RC) is not well defined. We sought to evaluate the association of adjuvant chemotherapy (AC) and overall survival (OS) among patients with adverse pathology after NAC and RC. Methods: The National Cancer Database was reviewed to identify patients with adverse pathology (pT3N0, pT4N0, or pTanyN1−3) at RC following NAC from 2006−2012. Patients were stratified by receipt of AC. Clinical and pathologic variables were abstracted. OS was the primary end−point and differences on the basis of AC were assessed by the Kaplan−Meier method and log−rank test. Multivariable Cox proportional hazards regression was used to assess the association of AC with OS controlling for age, sex, race, Charlson score, year of diagnosis, pathologic stage, and receipt of adjuvant radiotherapy. Results: Adverse pathology following NAC and RC was identified in 1,361 patients from 2006−2012, of whom 328 (24.1%) received AC. Staging was pT3N0 in 444 (32.6%), pT4N0 in 162 (11.9%), and pTanyN1−3 in 755 (55.5%). Median OS for the entire cohort was 22.9 months, which differed by pathologic stage: 34.6 months (pT3N0), 21.4 months (pT4N0), and 19.3 months (pTanyN1-3)(p < 0.01). No difference in OS was noted by receipt of AC in the overall cohort (median OS 24.6 months with AC vs 22.0 months without AC; p = 0.18), or when stratified by pathologic stage. On multivariable analysis, receipt of AC was not significantly associated with overall mortality (HR 0.86; 95%CI 0.74−1.01; p = 0.06) for all patients. When stratified by stage, AC was associated with a significantly decreased risk of mortality among patients with pT4N0 disease (HR 0.56; 95%CI 0.33−0.97; p = 0.04), but not pT3N0 or pTanyN1−3 (p > 0.05). Conclusions: Patients with adverse pathology at RC after NAC have a median OS of approximately 2 years. AC was not associated with improved survival, except in the subgroup with pT4N0 disease. Clinical trials with newer systemic therapies are warranted for patients in this setting.

364 Background: Venous thromboembolism (VTE) has been reported to occur in 2-5% of patients undergoing radical cystectomy (RC). While VTE is an important cause of perioperative morbidity, the association of these events with long-term cancer prognosis has not been established. Herein, we evaluated the association of perioperative VTE with patients’ risk of subsequent disease recurrence and mortality. Methods: We reviewed 2889 patients undergoing RC between 1980−2009 at the Mayo Clinic to identify patients diagnosed with a VTE within 90 days of RC. These cases were then matched in a 1:2 fashion to control patients undergoing RC who did not develop VTE. Matching was performed on the basis of age, BMI, receipt of neoadjuvant chemotherapy, and pathologic T and N stages. Recurrence-free (RFS), cancer-specific (CSS), and overall survival (OS) were estimated utilizing the Kaplan-Meier method and compared with the log-rank test. Results: A total of 132 patients with a VTE within 90 days of RC were identified, accounting for 4.6% of all patients analyzed. These cases were matched to 257 controls per criteria noted above, and were overall well-matched. Of the 389 patients in this study, median follow-up after RC was 9.2 years, during which time 152 (39%) patients experienced recurrence and 306 (78%) died, including 157 (40%) who died of bladder cancer. We found no significant difference in 5-year RFS (59% versus 61%; p = 0.75); CSS (57% versus 64%; p = 0.13); or OS (45% versus 50%; p = 0.15) between patients with versus without perioperative VTE, respectively. Conclusions: We found that VTE within 90 days of RC did not significantly impact long-term cancer outcomes. While these events represent an important cause of perioperative morbidity, no interaction with oncologic control was noted, and patients may be counseled accordingly.

355 Background: While neoadjuvant chemotherapy (NAC) prior to radical cystectomy (RC) improves survival compared to RC alone for urothelial carcinoma of the bladder (UCB), the bulk of this survival benefit has been attributed to patients who achieve ypT0 status at RC. The implications of having residual UCB (rUCB) at RC after NAC are less clear. As such, we evaluated whether the outcomes for patients with rUCB after NAC differ from stage-matched RC patients who did not receive NAC. Methods: Patients undergoing RC for UCB between 1981-2010 at Mayo Clinic were identified. All RC pathology was re-reviewed by a single genitourinary pathologist. Patients who received NAC were matched 1:2 to patients not exposed to NAC based on pT and pN-stage, margin status, and year of RC. Kaplan Meier and Cox regression analyses were used to evaluate the associations between NAC and cancer-specific (CSS) and overall survival (OS), stratified by presence of rUCB (i.e. (y)pT0N0 and non-(y)pT0N0). Results: We matched 111 patients who underwent NAC + RC to 222 RC-alone patients. Median age was 68 years (IQR 60,74); 59 (18%) were female. Median follow-up among survivors was 7.2 years (IQR 6,16). A total of 248 patients died; 148 died from UCB. In patients without rUCB at RC, there were no differences in 5-yr CSS (86% vs. 90%, p=0.85) or OS (82% vs. 84%, p=0.46) between patients who did and did not receive NAC. Moreover, on multivariable analysis, NAC exposure was not associated with CSS (HR=1.0; 95%CI 0.3-3.1; p=0.9) or OS (HR=0.9; 95%CI 0.4-1.9; p=0.8) in this subgroup. Among patients with rUCB, receipt of NAC was associated with significantly worse 5-yr CSS (32% vs. 56%, p<0.001) and OS (25% vs. 48%, p<0.001). NAC exposure remained independently associated with worse CSS (HR=2.2; 95%CI 1.6-3.1; p<0.001) and OS (HR=2.0; 95%CI 1.5-2.7; p<0.001) among these patients. Conclusions: While patients who achieve a complete response to NAC have excellent survival outcomes, patients with residual UCB at RC after NAC have a worse prognosis compared to stage-matched RC patients not exposed to NAC. Such patients should be considered for enrolment in novel adjuvant therapy trials.

312 Background: Radical cystectomy (RC) is a preferred option for high−grade non−muscle invasive bladder cancer (HG NMIBC), particularly after failure of intravesical therapy. However, clinicians may be reluctant to offer surgery to older patients with NMIBC given concerns regarding morbidity. We therefore sought to evaluate the association of age with use of RC and clinicopathologic outcomes after RC for HG NMIBC. Methods: The National Cancer Data Base was queried to identify patients diagnosed with HG NMIBC between 2004−2013. Patients were stratified according to age at diagnosis: <60, 61−70, 71−80, >80 years. Multivariable logistic regression was performed to assess the associations of age group with utilization of RC and with pathologic upstaging (pT2−4 or pN+). Overall survival (OS) was evaluated using unadjusted and inverse propensity score weighted (IPTW) Kaplan−Meier methods and compared with the log-rank test. Results: RC was performed in 3,641 (5.7%) of 63,402 patients with HG NMIBC. Utilization of RC remained relatively constant over the study period (4.3%−6.8%; p=0.44). On multivariable analysis, increasing age was inversely associated with RC utilization, with the lowest utilization in those >80 (2.1% rate; OR 0.24; p<0.01). Similar associations of age with RC were observed at high volume centers (> 15 cases/year), academic centers, and for patients with cT1 disease. Among patients who underwent RC, pathologic upstaging was identified in 1,445 (43.6%), and no significant association was noted with age. NMIBC pathologic tumor stage was associated with improved OS compared to progression to pT2−4 or N+ disease at RC for all age groups: median OS improvement not reached in those under 60; 32 months in those 61−70; 55 months in those 71−80; and 34 months in those over 80 (all p<0.01). Similar improvements in survival were noted after IPTW. Conclusions: Older patients are significantly less likely to receive RC for HG NMIBC, despite a similar risk of upstaging and an improved survival when pathologic NMIBC is found at RC. These data support the use of RC for HG NMIBC in well selected patients across age strata.

308 Background: Receipt of pelvic radiotherapy (PRT) prior to radical cystectomy (RC) has unclear association on oncologic outcomes. Methods: The Mayo Clinic Cystectomy Registry was queried to review 2139 patients undergoing RC for M0 bladder cancer between 1990 and 2010. We then identified patients receiving PRT prior to RC, and matched these cases to non-radiated controls (~1:2) on the basis of age, sex, receipt of neoadjuvant chemotherapy, and pathologic T and N stages. Cancer-specific survival (CSS), and progression-free survival (PFS) were estimated using the Kaplan-Meier method and compared with the log-rank test. Results: Of 2139 patients undergoing RC, 104 (4.9%) had received PRT prior to surgery. These patients were matched to 191 non-radiated control patients (no PRT). Overall, patients were well-matched on disease and patient characteristics. Median follow-up was 9.6 years (IQR 6.0, 14.8). During this time, 108 patients experienced disease recurrence and 218 died, including 122 who died from bladder cancer. Five-year CSS among patients who did versus did not receive PRT was 55% versus 63% (p=0.10), while the 5-year PFS was 55% versus 61% (p=0.32). Furthermore, the pattern of disease recurrence (abdominal/visceral, urothelial, local/pelvic, thoracic, soft tissue/other) did not differ between the no PRT and PRT groups (all p>0.05). Conclusions: Receipt of PRT prior to RC is not associated with worse oncologic outcomes. While prior PRT may increase surgical complexity, CSS, PFS, and patterns of recurrence are similar to patients who have not received PRT.

Objective To evaluate the association between renal tumour complexity and outcomes in a large cohort of patients undergoing percutaneous cryoablation ( PCA ). Patients and Methods Patients with renal tumours treated with PCA were identified using our prospectively maintained ablation registry (2003–2015). Salvage procedures and inherited tumour syndromes were excluded. The associations between R.E.N.A.L. nephrometry score ( NS ) and risk of complications, renal function impairment, local failure and cancer‐specific mortality ( CSM ) were evaluated using univariate and multivariable logistic, linear and Cox regression models. Results The cohort included 618 tumours treated during 580 procedures in 565 patients. The median (interquartile range [ IQR ]) follow‐up was 34 (14.66) months. Complications (any grade) during a procedure ( n [total] = 87, 15%) were more frequent with higher NS ( NS 4–6: 10%; NS 7–9: 14%; NS 10–12: 36%; P < 0.001). Higher NS was independently associated with risk of complications (odds ratio [ OR ; per 1 point] = 1.3; 95% confidence interval [ CI ] 1.2–1.5; P < 0.001). Of all the NS components, tumour size was the most strongly associated with complication risk ( OR 3.4; 95% CI 2.2–5.2; P < 0.001). The median ( IQR ) decline in glomerular filtration rate ( GFR ) from baseline was 9% (0, 22) at last follow‐up. Each additional point in NS was associated with a 1.3% (95% CI 0.4–2.1; P = 0.005) greater GFR decline from baseline. NS was not significantly associated with local failure ( n [total] = 14, 2%; NS 4–6: 2%; NS 7–9: 3%; NS 10–12: 5%; P = 0.32) or CSM ( n [total] = 8, 2%; NS 4–6: 2%; NS 7–9: 3%; NS 10–12: 2%; P = 0.88). Conclusion In high‐complexity tumours PCA was associated with a tumour size‐driven increased risk of post‐procedural complications. Higher NS was associated with a small, clinically minor additional decline in renal function. Risks for local failure and CSM were low, regardless of tumour complexity.

516 Background: The impact of diabetes mellitus (DM) on outcomes in patients with renal cell carcinoma (RCC) is controversial. Herein, we evaluated the association of DM with survival among patients with RCC. Methods: We reviewed 2,589 patients treated with nephrectomy for sporadic, unilateral, M0 RCC between 1990 and 2008 and compared demographic and tumor characteristics in patients with and without DM (nonDM). Patients with DM (n=313) were matched 1:2 to nonDM patients according to date of surgery, age, smoking status, obesity, ECOG performance status (PS), CKD stage, histological subtype, and nuclear grade. Cancer-specific (CSS) and overall survival (OS) were compared by Kaplan-Meier analysis. The association of DM with outcomes was evaluated with Cox proportional hazards regression models. Results: A total of 313 (12%) patients had DM. DM patients were significantly older at RCC diagnosis, more likely to be obese, and had higher Charlson scores, CKD class, rates of smoking, and worse PS at surgery (p<0.001). Patients with DM were also more likely to have ccRCC (83% vs. 76%, p=0.02) and to undergo nephron-sparing surgery (42% vs. 35%, p=0.01), while other pathologic features were similar in DM and nonDM. Among the 939 matched cases and controls, 463 patients died within a median of 5.5 years after nephrectomy. Median follow-up for survivors was 8.6 years. Five-year CSS was not significantly different among DM patients 84% vs. nonDM patients 87% (p=0.11), although 5-year OS was significantly worse among DM patients (66% vs. 75%; p<0.001). Indeed, even after adjusting for Charlson score, DM patients were noted to have a significantly increased risk of all-cause mortality (HR 1.33; p=0.004). In a subanalysis of patients with clear cell RCC, DM patients were more likely to die from RCC compared with nonDM patients after adjusting for the SSIGN (Stage, Size, Grade, Necrosis) score (HR 1.44; p=0.034). Conclusions: In this surgical cohort, DM was independently associated with decreased CSS among patients with ccRCC and with decreased OS in all RCC subtypes. Further studies to determine the potential biologic mechanism for this interaction are warranted.