Safety and Efficacy of Retrograde Pyeloperfusion for Ureteral Protection during Renal Tumor Cryoablation

PURPOSE

To determine safety and efficacy of retrograde pyeloperfusion for ureteral protection during cryoablation of adjacent renal tumors.

MATERIALS AND METHODS

Retrospective review of 155 patients treated with renal cryoablation, including adjunctive retrograde pyeloperfusion, from 2005 to 2019 was performed. Ice contacted the ureter in 67 of the 155 patients who represented the study cohort. Median patient age was 68 years old (interquartile range [61, 74]), 52 patients (78%) were male, and 37 tumors (55%) were clear cell histology. Mean tumor size was 3.4 ± 1.3 cm, and 42 tumors (63%) were located at the lower pole. Treatment-related complication and oncologic outcomes were recorded based on a review of post-procedural images and chart review.

RESULTS

Technical success of cryoablation was attained in 67 cases (100%), and technical success of pyeloperfusion was attained in 66 cases (99%). A total of 13 patients (19.4%) experienced SIR major C or D complications related to the procedure, including hemorrhage (n = 4), urine leak (n = 3), transient urinary obstruction (n = 2), pulmonary embolism (n = 1), hypertensive urgency (n = 1), acute respiratory failure (n = 1), and ureteropelvic junction (UPJ) stricture (n = 1). No complications were attributable to pyeloperfusion. Three of 45 patients with biopsy-proven renal cell carcinoma experienced local recurrence resulting in local recurrence-free survival of 92% (95% confidence interval, 81.5%-100%) 3 years after ablation.

CONCLUSIONS

Retrograde pyeloperfusion of the renal collecting system is a relatively safe and efficacious option for ureteral protection during renal tumor cryoablation. This adjunctive procedure should be considered for patients in whom cryoablation of a renal mass could potentially involve the ureter.

The association of anxiety and depression with mortality risk among patients with clear cell renal cell carcinoma undergoing nephrectomy

617

Background: Anxiety and depression are psychosocial factors which have been demonstrated to have mixed interactions with mortality across various malignancies. While these variables have been associated with poor overall survival for patients with metastatic RCC, the influence on outcomes for localized RCC has been poorly studied. We evaluated the association of anxiety or depression with survival in patients with surgically treated localized clear cell RCC (ccRCC). Methods: We performed retrospective review of our institutional nephrectomy registry to identify 1,990 patients who underwent radical or partial nephrectomy for unilateral, sporadic, non-metastatic ccRCC between 1995- 2011. Baseline anxiety and depression were identified using ICD-9 codes. Associations of anxiety or depression with outcomes of interest were evaluated using Cox proportional hazards models. Two propensity score (PS) techniques were used: adjusting for PS quintile and re-weighting by stabilized inverse probability weights. Results: A total of 197 (10%) patients had diagnoses of anxiety or depression (57 had anxiety alone, 107 had depression alone, and 33 had both anxiety and depression). Median follow-up among survivors was 10.0 (IQR 7.3-13.6) years, during which time 864 died, including 363 from RCC. Patients with anxiety or depression were younger (mean age 59 vs 62 years, p < 0.001) and had more recent operations (75% vs 47% in 2005-2011, p < 0.001) compared to those with neither diagnosis. After PS adjustment, all clinical and pathologic features were well balanced between groups. After PS adjustment, there were no significant differences in time to local ipsilateral recurrence, distant metastases, and death from RCC between groups. We did note a trend to poorer overall survival in patients with anxiety or depression (HR 1.29, 95%CI = 0.98-1.69, p = 0.065). Conclusions: Our results suggest that neither anxiety nor depression is significantly associated with oncologic outcomes among patients with localized surgically treated ccRCC. The trend toward worse overall survival among patients with anxiety or depression warrants further investigation.

The probability of indolent versus aggressive histology based on renal tumor size: Implications for surveillance and treatment

704

Background: While the probability of benign versus malignant histology based on renal tumor size has been described, this alone does not sufficiently inform decision-making in the modern era since indolent malignant tumors can be surveilled. Thus, we sought to characterize the probability of indolent versus aggressive histology based on radiographic tumor size. Methods: We evaluated patients who underwent radical or partial nephrectomy at Mayo Clinic for a pT1-2, pNx/0, M0 solid renal tumor between 1990-2010. Pathology was reviewed by one genitourinary pathologist. Benign tumors, low grade (1-2) clear cell and papillary renal cell carcinoma (RCC), and any chromophobe, clear cell papillary, mucinous tubular and spindle cell, SDH-B deficient, and tubulocystic RCC were considered indolent. All other histologies were considered aggressive, as were any malignancies with necrosis or sarcomatoid differentiation. Cancer-specific survival (CSS) was estimated using the Kaplan Meier method. Logistic regression models were used to estimate the probability of malignant and aggressive histology based on tumor size. Sex-stratified analyses were also performed. Results: Of the 2650 patients included, there were 1773 patients with indolent tumors (303 benign; 1470 malignant) and 877 with aggressive tumors. Ten-year CSS was 96% for indolent malignant tumors and 82% for aggressive tumors. The predicted probabilities of any malignant histology and aggressive malignant histology increased with tumor size (Table; 1-7cm point estimates shown). For example, a 3 cm tumor had an 87% probability of malignancy and a 27% probability of being aggressive. For any given tumor size, men had a greater probability of aggressive histology than women. Conclusions: We present tumor size-based estimates of the probability of aggressive histology for renal masses. This information should be useful for patient counseling and treatment decision-making. [Table: see text]

Survival following upfront cytoreductive nephrectomy versus targeted therapy for metastatic renal cell carcinoma

672

Background: The optimal sequence of cytoreductive nephrectomy (CN) and targeted therapy (TT) for patients with metastatic renal cell carcinoma (mRCC) remains to be established. Herein, we compared overall survival (OS) between patients with mRCC receiving initial CN with or without subsequent TT versus initial TT with or without subsequent CN. Methods: The National Cancer Database (NCDB) was used to identify patients diagnosed between 2006-2013 with RCC that was metastatic at diagnosis who received CN, TT, or both. Those with other prior cancer history were excluded. The cumulative incidence of receiving TT after CN and CN after TT were evaluated, with death prior to second treatment as a competing risk. To account for treatment selection bias, inverse probability of treatment weighting (IPTW) was performed based on the propensity to receive initial CN or TT. OS from diagnosis was compared using Cox regression. Sensitivity analyses were performed. Results: The cohort included 15,068 patients, of whom 6,731 underwent initial CN and 8,337 underwent initial TT. At 6 months from diagnosis, the probability of receiving TT after CN was 46.2%, with 13.6% of patients having died after initial CN prior to receiving TT. Meanwhile, the probability at 6 months of undergoing CN after initial TT was 4.4%, with 38.3% of this group having died prior to undergoing CN. In the IPTW analysis, baseline characteristics were balanced (standardized difference < 0.1). Initial CN was associated with improved OS compared to initial TT (median 16.5 vs 9.2 months; HR 0.62; 95%CI 0.61-0.64; p < 0.001). Findings were similar in all sensitivity analyses (propensity score matching and adjustment; regression adjustment; 6-month landmark analysis; clear cell mRCC subset; exclusion of patients who had metastasectomy). Conclusions: Although initial CN was associated improved OS versus initial TT in this national dataset, initial CN was associated with delays in, and even death prior to, receipt of TT. As such, while the survival data here support initial CN in appropriate surgical candidates, continued efforts to develop the optimal multimodal approach to these patients are warranted.

Creation of a tissue expression biomarker-augmented prognostic model for patients with metastatic renal cell carcinoma

703

Background: Clinical and pathologic factors alone have limited prognostic ability in patients with metastatic clear cell renal cell carcinoma (ccRCC). We sought to determine if tissue biomarkers, along with our previously reported clinical metastases score, can be used to predict cancer specific survival (CSS) in patients with metastatic ccRCC. Methods: Patients with metastatic ccRCC who underwent nephrectomy between 1990-2004 were identified using the Mayo Clinic Nephrectomy Registry. Sections from paraffin-embedded primary tumor tissue blocks were used for immunohistochemistry staining for PD-1, B7-H1 (PD-L1), B7-H3, Bim (downstream pro-apoptotic signaling molecule in PD-1 pathway), CA-IX, IMP3, Ki67, and survivin. CSS was the primary outcome. Biomarkers that were significantly associated with CSS after adjusting for the metastases score were used to develop a biomarker-specific multivariable model using a bootstrap resampling approach and forward selection. Predictive ability was summarized using a bootstrap-corrected c-index. Results: The cohort included 602 patients, 192 (32%) with metastases at diagnosis and 410 (68%) who developed metastases after nephrectomy. Median follow-up among survivors was 9.6 years (IQR 4.2,12.8) and 504 patients died of RCC. Bim, IMP3, Ki67, and survivin expression were significantly associated with CSS after adjusting for the metastases score and were used to develop a biomarker-specific model. High Bim (HR 1.44; 95%CI 1.16-1.78; p < 0.001), high survivin (HR 1.35; 95%CI 1.08-1.68; p = 0.008), and the metastases score (HR 1.13 per one point; 95%CI 1.10-1.16; p < 0.001) were retained as independent predictors in the final multivariable model (c-index 0.69). Conclusions: We created a prognostic model combining the clinical metastases score and two primary tissue expression biomarkers, Bim and survivin, for patients with metastatic RCC who underwent nephrectomy. External validation will be required prior to clinical use.

Exploring the association between renal cell carcinoma (RCC) and myeloid malignancies

e13073

Background: We observed several patients with a personal history of both RCC and myeloid malignancy, and aimed to explore a possible association, especially given the similarity in their epigenetic landscape, with both being characterized by widespread aberrant hypermethylation (Hu C et al, CCR 2014; Jiang Y et al, Blood 2009). Methods: Mayo Clinic’s ‘Advanced Cohort Explorer’ database was used to identify patients with a history of both RCC and a myeloid malignancy - Acute Myelogenous Leukemia (AML), Myeloproliferative Neoplasms (MPN), Myelodysplastic syndromes (MDS) - and to determine the clinical characteristics. The incidence of MDS in patients ≥65 years with a history of RCC was compared to that in the general population ≥65 years (SEER- Medicare database) as well as the general patient population at Mayo Clinic, using one sample test of proportions. Results: A total of 59 patients were identified, with both biopsy proven RCC and a myeloid malignancy during their life time (12 AML, 9 MPN, 9 low risk MDS and 29 intermediate- high risk MDS). The cohort was characterized by marked male predominance (4.4: 1). Median age at RCC diagnosis was 64 years (range 37-87) and myeloid malignancy was 75 years (range 44-90). 46/59 patients had the RCC antecedent, 10/59 concurrent and 3/59 subsequent to the myeloid malignancy with a median time of myeloid malignancy diagnosis after RCC diagnosis of 7.7 years. For patients ≥65 years, the risk of developing MDS with a history of stage I/II RCC and nephrectomy was 5.26 times that of the general population based on the SEER-Medicare database (Cogle, Blood 2011)(395/100,000 vs 75/100,000; p value < 0.001), and 3.07 times that of the general population at Mayo Clinic (395/100,000 vs 128.4/100,000; p value < 0. 001). Conclusions: We observed an association between RCC and myeloid malignancies, particularly MDS; with a history of RCC conferring a substantially increased risk of developing MDS. We hypothesize that the perturbation of epigenetic landscape in the form of widespread hypermethylation may explain, in part, the association between the two malignancies; and aim to explore the potential aberrancy of epigenetic regulators in our patient cohort with a genomic, epigenomic and transcriptomic analysis.

Cryoablation of cT1 renal masses in the “healthy” patient: Early outcomes from Mayo Clinic

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.

Clinicopathologic characterization and outcomes for patients with renal medullary carcinoma: Results from the National Cancer Database

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.

Association of age with utilization of radical cystectomy for high-grade nonmuscle invasive bladder cancer: Results from the National Cancer Database

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.

Association of perioperative venous thromboembolism with long-term oncologic outcomes following radical cystectomy

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.

Survival for patients with residual tumor at radical cystectomy following chemotherapy: A matched analysis to cystectomy-only patients

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.

Association of prior pelvic radiation with long-term oncologic outcomes following radical cystectomy

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.

The effect of adjuvant chemotherapy for patients with adverse pathology after neoadjuvant chemotherapy for muscle invasive bladder cancer

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.

Separation of pairs of C-24 epimeric sterols by glass capillary gas liquid chromatography

Paris of C-24 epimeric sterols have been very difficult to separate by physical emthods. We report here the partial or complete separation of the trimethylsilyl ethers of nine pairs of C-24 epimeric sterols by gas liquid chromatography on a glass capillary column coated with SP-2340. The trimethylsilyl ethers of the epimeric pairs of sterols with saturated side chains and a pair with two double bonds in the side chain were completely separated from each other by GLC. The epimeric pairs with a double bond at C-22 showed partial separation. The 24β-epimer with a saturated side chain eluted before the corresponding 24α-epimer. This order was reversed for pairs of C-24 epimeric sterol trimethylsilyl ethers containing a double bond in the side chain at C-22.

Immunotherapy in prostate cancer

Immunotherapy for the treatment of malignant neoplasms has made significant progress over the last 20 years. Multiple molecular targets and clinical agents have been developed recently, particularly in the field of metastatic adenocarcinoma of the prostate. Sipuleucel-T is currently the only FDA approved immunotherapy for prostate cancer. PSA-TRICOM (Prostvac) currently has a phase III randomized trial underway after a phase II trial showed an improvement in overall survival. Interestingly, both these agents showed improvement in overall survival with no measurable change in disease state, leading to significant controversy as the utility of these agents in prostate cancer. Ipilimumab revealed a benefit for a sub-cohort of men in a post-docetaxel group and is currently undergoing investigation in a pre-docetaxel group. There are a number of other targets such as PD-1 which have shown effectiveness in other neoplasms that will likely be investigated in the future for use in prostate cancer.

Paraneoplastic syndromes are associated with adverse prognosis among patients with renal cell carcinoma undergoing nephrectomy

OBJECTIVES

To analyze the association of paraneoplastic syndromes (PNS) with progression-free (PFS) and cancer-specific survival (CSS) among patients with renal cell carcinoma (RCC) undergoing nephrectomy.

METHODS

We performed a retrospective analysis of 2865 patients undergoing nephrectomy for localized RCC at Mayo Clinic from 1990 to 2010. PNS analyzed were anemia, polycythemia, hypercalcemia, recent-onset hypertension, and liver dysfunction. PFS and CSS were estimated using Kaplan-Meier method and compared with Cox proportional hazard models, unadjusted and adjusted for clinicopathologic features.

RESULTS

A total of 661 (23 %) patients had anemia, 37 (1 %) had polycythemia, 177 (9 %) had hypercalcemia, 51 (2 %) had recent-onset hypertension, and 224 (10 %) had liver dysfunction at time of nephrectomy. Patients with PNS were more likely to have high-grade tumors and advanced disease stages. A total of 675 (24 %) patients developed progression and 1171 (41 %) died of RCC, over a median follow-up of 8.2 years. On univariable analysis, the presence of any PNS was associated with inferior CSS [hazard ratio (HR) = 1.86, p = 0.007] and a trend toward shorter PFS (HR = 1.33, p = 0.07) compared with patients without PNS. Specifically, anemia, polycythemia, hypercalcemia, and liver dysfunction were each associated with inferior CSS and PFS (all p < 0.05). However, on multivariable analysis PNS (overall or each individual syndrome) did not remain independently associated with CSS or PFS.

CONCLUSIONS

Patients with RCC undergoing nephrectomy presenting with PNS have worse oncologic outcome than those with incidentally found tumors. However, the adverse outcome among PNS patients seems to be largely explained by adverse pathologic features of these tumors.

Safety and efficacy of extended-duration thromboembolic prophylaxis following radical cystectomy

389

Background: Venous thromboembolism (VTE) has been reported in approximately 5-7% of patients undergoing radical cystectomy (RC). While extended-duration pharmacologic prophylaxis (EDPP) has been investigated following surgery for a variety of malignancies, limited data exist in bladder cancer. Herein, we evaluated the efficacy and safety of EDPP after RC. Methods: We instituted a change in our clinical practice beginning in May 2014 such that patients undergoing RC were prescribed 30 days of enoxaparin at discharge. We recorded symptomatic VTE and lymphocele rates within 30 days of RC among patients treated from 5/14-6/15, and compared these outcomes to the cohort of all patients who underwent RC at our institution in the year prior to EDPP implementation. Patients in both groups received subcutaneous unfractionated heparin and mechanical prophylaxis during hospitalization. Patients with a history of VTE prior to surgery (n = 24) were excluded from study. Unadjusted descriptive statistics and univariate analyses were performed using the Pearson or Fisher chi-square test for categorical variables and Wilcoxon rank-sum test for continuous variables. Results: In total, 58 patients who received EDPP and 82 patients who had not received EDPP after RC were included for analysis. Baseline clinicopathologic demographics were similar between the cohorts. We found that only 1 patient (1.9%) discharged with EDPP was diagnosed with a VTE within 30 days of RC, compared to 5 (6.1%) who had not received EDPP. Mean time to VTE was 18.0 days after RC (range 9-28 days). Events consisted of DVT alone (n = 2), DVT and PE (n = 2), and PE alone (n = 2). The odds ratio for VTE in the absence of EDPP was 3.31 (95% CI 0.38, 29.2). Overall, 3 patients developed a symptomatic lymphocele within 30 days of RC: 1 (1.9%) who received EDPP and 2 (2.4%) who had not (p = 0.84). No patient in either cohort was rehospitalized for bleeding complications. Conclusions: Our initial experience suggests that EDPP was associated with a lower rate of VTE following RC, and does not increase the risks of bleeding or symptomatic lymphocele. Future evaluation in a larger-scale prospective clinical trial setting is needed to confirm the benefit of EDPP in RC patients.

Understanding the genomic underpinnings of metastatic chromophobe renal cell carcinoma

513

Background: Chromophobe renal cell carcinoma (chRCC) is the third most common histologic subtype of kidney cancer. While most of these tumors have an indolent behavior, 7% of patients with chRCC develop metastases, with no currently available standard of care. The Cancer Genome Atlas characterized chRCC, highlighting pathognomonic single copy chromosomal losses of 1, 2, 6, 10, 13 and 17, as well as a minimal mutation burden distinguishing it from all other cancer types. However, only 15% of the analyzed patients had advanced disease. We analyzed metastatic chRCC to further characterize these tumors and elucidate mechanisms leading to aggressive disease using a variety of next generation and whole genome sequencing. Methods: Our cohort of metastatic chRCC consisted of 40 patients with available clinical and pathologic data. Whole genome sequencing (WGS) was performed on 6 patients (4 primary tumors and 2 metastases), 42 additional samples from 33 patients were analyzed using targeted next-generation sequencing (MSK-IMPACT). Notably, we were able to collect and analyze matched primary and metastatic tumors from 7 patients. As control cohort 27 non-metastatic chRCC tumors were sequenced with MSK-IMPACT. Copy number patterns were computed with OncoSNP seq and FACETS. Results: The most commonly mutated genes in the aggressive chRCC tumors were TP53 and PTEN (WGS: TP53 67 %, PTEN 33%; MSK-IMPACT: TP53 61%, PTEN 27%). No other genes were mutated frequently. Primary tumor samples of chRCC did show the typical pattern of chromosomal losses in 1, 2, 6, 10, 13 and 17. Interestingly, these canonical losses could not be detected in the metastases even when accounting for tumor purity. Conclusions: TP53 and PTEN mutations are highly enriched in both primary and metastatic tumors of aggressive chRCC compared to the non-aggressive tumors and likely play a critical role in disease progression. More intriguingly, the observation of differential copy numbers in matched primary and metastatic tumors suggest whole genome or whole chromosome events in these samples. We are currently employing different bioinformatic and cytogenetic platforms to validate our novel hypothesis of chromosomal events as driver for metastatic development in chRCC.

Mapping prostate cancer (CaP) recurrence after prostatectomy with c-11 choline PET/CT and 3T pelvic MRI in the contemporary era

255

Background: The purpose of this study was to identify site-specific recurrence patterns for patients (pts) with biochemical recurrence (BCR) after prostatectomy (RP) using C-11 Choline PET/CT (C11Ch) and 3T pelvic MRI with endorectal coil (pMRI). Methods: Between 2008 and 2006, 2,466 men underwent C11Ch and pMRI for BCR after RP. From this cohort, we identified 261 pts who received no adjuvant or salvage therapy (androgen deprivation or radiation). Suspected radiographic relapse was confirmed by biopsy (46%) or progression/response to treatment in concordance with subsequent rise/decline in PSA (54%). Results: Of the 261 men evaluated, 202 (75%) had positive pMRI, C11Ch or both. Seventy nine (39%), 105 (52%) and 18 (9%) pts had high, intermediate, and low risk CaP, respectively at RP. Median PSA at the time of positive scan was 2.3 ng/mL, with a median time from BCR to radiographic disease identification of 15 months. Of these 202 men, 67 (33%) harbored prostate fossa recurrence only, 44 (22%) had a combination of local and metastatic disease and 91 (45%) had metastatic disease without local recurrence. Forty (20%) pts had pelvic nodal recurrence only and 18 (9%) had perirectal nodal involvement. Median PSA for pts with local only recurrence, distant metastases only, and local + distant disease was 2.3, 2.7 and 2.2 ng/mL, respectively, with a median interval from BCR to positive scan of 16.7, 7.9 and 11 months. Imaging revealed that 33% to 66% of our cohort would have all sites of disease treated by salvage RT depending on the extent of the treatment field Conclusions: C11Ch and pMRI were used to identify recurrence patterns in pts with BCR after RP only. At median PSA of 2.3 ng/ml, our study demonstrates a low rate of local-only recurrence, higher than anticipated frequency of metastatic recurrence with peak frequency within the pelvic lymph nodes, and substantial perirectal recurrences. Despite the high rates of distant recurrences, 2/3 of our cohort had their disease limited to the pelvis and could be potential candidates for local therapies, including salvage radiation.

Incidence, timing, and risk factors for infection after radical cystectomy: Results from the National Surgical Quality Improvement Program

445

Background: Radical cystectomy (RC) is the gold standard treatment for muscle-invasive and high-risk non-muscle invasive bladder cancer. However, the procedure has been associated with a high complication rate, including perioperative infection. In addition to resulting in patient morbidity, infections have been suggested as a quality metric. We sought to evaluate the incidence, risk factors, and timing of infection following RC. Methods: The National Surgical Quality Improvement Program (NSQIP) database was queried to identify patients undergoing RC for bladder cancer from 2005-2013 using CPT procedure and ICD-9 diagnosis codes. Infections (urinary tract infection (UTI), surgical site infection (SSI), and sepsis) within 30 days of RC were recorded. Characteristics including age, gender, ethnicity, body-mass index, diabetes, smoking status, renal function, steroid usage, albumin, receipt of perioperative transfusion, and operative time were abstracted, and relative risk of infection was assessed in univariate chi-squared analysis. Results: A total of 3,187 patients were identified, of whom 2604 (81.8%) were male, with a median age of 68.8 years (IQR 62, 77). Postoperative infection was diagnosed in 766 (24%) patients, at a median of 13 days (IQR 8, 19) after RC, with 44.4% occurring prior to hospital discharge. The most common type of infection was SSI (404; 12.7%), followed by sepsis (315; 9.9%), and UTI (309; 9.7%). Factors associated with increased overall infection risk were obesity (RR 1.32; 1.20-1.46; p < 0.001), receipt of a blood transfusion (RR 1.20; 1.10-1.31; p < 0.001), and increased operative time (RR for > 450 min 1.46; 1.26-1.70; p < 0.001). Risk factors for UTI in particular included obesity (RR 1.28; 1.11-1.47; p < 0.001), diabetes (RR 1.38; 1.09-1.75; p = 0.009), and increased operative time (RR for > 450 min 1.45; 1.18-1.78; p < 0.001). Conclusions: Approximately 25% of patients undergoing RC experience an infection within 30 days of surgery, most commonly SSI. Several modifiable risk factors were identified, including blood transfusion and prolonged operative time, that represent potential targets for care improvement.

Clinicopathologic characteristics and survival for adult renal sarcoma: A population-based study

INTRODUCTION

To analyze the association of clinicopathologic characteristics and treatment modality with survival among adult patients with renal sarcoma.

METHODS

We identified 489 adults diagnosed with renal sarcoma from the Surveillance, Epidemiology and End Results registry between 1973 and 2011. Cancer-specific survival was estimated using the Kaplan-Meier method and was compared between groups with log rank and Cox models.

RESULTS

Median age at diagnosis was 61 years, while median tumor size was 11 cm. Tumor histology was leiomyosarcoma in 175, liposarcoma in 100, other subtypes in 129, and unknown in 85 cases. Tumor stage at diagnosis was nonmetastatic in 322 (67%) and metastatic in 167 (33%) cases. Treatment of nonmetastatic disease was surgical resection in 171 patients, radiation in 24, both in 35, neither in 18, and unknown in 74 cases. Treatment of metastatic disease was surgery in 39 patients, radiation in 27, both in 11, neither in 42, and unknown in 48. For nonmetastatic and metastatic disease, 5-year cancer-specific survival rates were 58% and 16%, respectively. On multivariable analysis, surgery was associated with decreased cancer-specific mortality among both patients with nonmetastatic disease (hazard ratio = 0.34; 95% CI: 0.14-0.85) and those with metastatic disease (hazard ratio = 0.38; 95% CI: 0.18-0.77). Age, race, tumor size, and tumor grade were independently associated with cancer death in nonmetastatic disease, whereas race and tumor histology remained associated with mortality in metastatic disease (all P < 0.05).

CONCLUSION

Although metastatic renal sarcoma has an ominous prognosis, durable survival may be achieved for localized tumors. Although we recognize the potential for selection bias, our results suggest an association between surgical resection and decreased mortality for both nonmetastatic and metastatic renal sarcoma.

Evaluation of pT0 prostate cancer in patients undergoing radical prostatectomy

OBJECTIVE

To evaluate the incidence, predictors and oncological outcomes of pT0 prostate cancer (PCa).

METHODS

We conducted a retrospective analysis of 20 222 patients undergoing radical prostatectomy (RP) for PCa at the Mayo Clinic between 1987 and 2012. Disease recurrence was defined as follow-up PSA >0.4 ng/mL or biopsy-proven local recurrence. Systemic progression was defined as development of metastatic disease on imaging. Comparisons of baseline characteristics between pT0 and non-pT0 groups were carried out using chi-squared tests. Recurrence-free survival was estimated using the Kaplan-Meier method and compared using the log-rank test.

RESULTS

A total of 62 patients (0.3%) had pT0 disease according to the RP specimen. In univariable analysis, pT0 disease was significantly associated with older age (P = 0.045), lower prostate-specific antigen (PSA; P = 0.002), lower clinical stage (P < 0.001), lower biopsy Gleason score (P = 0.042), and receipt of preoperative transurethral resection, hormonal and radiation therapies (all P < 0.001). In multivariable analysis, lower PSA levels, lower Gleason score, and receipt of preoperative treatment were independently associated with pT0 (all P < 0.05). Seven patients (11%) with pT0 PCa developed disease recurrence over a median follow-up of 10.9 years. All seven patients had preoperative treatment(s) and three had recurrence with a PSA doubling time of <9 months. Compared with non-pT0 disease, pT0 disease was associated with longer recurrence-free survival (P < 0.05). Only one (1.6%) patient with pT0 disease developed systemic progression.

CONCLUSIONS

pT0 stage PCa is a rare phenomenon and is associated with receipt of preoperative treatment and features of low-risk PCa. Although pT0 has a very favourable prognosis, some men, especially those who received preoperative treatment, experience a small but non-negligible risk of disease recurrence and systemic progression.

Preoperative multivariable prognostic models for prediction of survival and major complications following surgical resection of renal cell carcinoma with suprahepatic caval tumor thrombus

OBJECTIVE

Surgical resection for renal cell carcinoma (RCC) with suprahepatic inferior vena cava tumor thrombus is associated with significant morbidity, yet there are currently no tools for preoperative prognostic evaluation. Our goal was to develop a preoperative multivariable model for prediction of survival and risk of major complications in patients with suprahepatic thrombi.

METHODS

We identified patients who underwent surgery for RCC with suprahepatic tumor thrombus extension from 2000 to 2013 at 4 tertiary centers. A Cox proportional hazard model was used for analysis of overall survival (OS) and logistic regression was used for major complications within 90 days of surgery (Clavien ≥ 3A). Nomograms were internally calibrated by bootstrap resampling method.

RESULTS

A total of 49 patients with level III thrombus and 83 patients with level IV thrombus were identified. During median follow-up of 24.5 months, 80 patients (60.6%) died and 46 patients (34.8%) experienced major complication. Independent prognostic factors for OS included distant metastases at presentation (hazard ratio = 2.52, P = 0.002) and Eastern Cooperative Oncology Group (ECOG) performance status (hazard ratio = 1.84, P<0.0001). Variables associated with increased risk of major complications on univariate analysis included preoperative systemic symptoms, level IV thrombus, and elevated preoperative alkaline phosphatase and aspartate transaminase levels; however, only systemic symptoms (odds ratio = 8.45, P<0.0001) was an independent prognostic factor. Preoperative nomograms achieved a concordance index of 0.72 for OS and 0.83 for major complications.

CONCLUSIONS

We have developed and internally validated multivariable preoperative models for the prediction of survival and major complications in patients with RCC who have a suprahepatic inferior vena cava thrombus. If externally validated, these tools may aid in patient selection for surgical intervention.

Association and prognostic impact of peripheral blood counts with tumor programmed death ligand one expression

447

Background: Components of the peripheral blood counts (PBC) are associated with poor prognosis in patients diagnosed with non-metastatic clear cell renal cell carcinoma (ccRCC). Related to this, higher tumor expression of programmed death ligand one (PDL1) is also associated with poor ccRCC prognosis. Herein, we utilize a large cohort of patients undergoing nephrectomy for localized ccRCC to evaluate the association of PBC with tumor expression of PDL1. Secondarily, we examine the association of PBC and relapse free survival (RFS) after adjusting for age and PDL1 expression. Methods: Through chart review, we obtained PBC values at time of nephrectomy for patients enrolled in the Mayo Clinic Renal Registry from 1990-2009 who were treated for localized (M0) ccRCC including the following: hemoglobin (HGB), white blood cell (WBC), absolute neutrophil count (ANC), absolute lymphocyte count (ALC), absolute eosinophil count (AEC), absolute monocyte count (AMC), and platelets (PLT). We determined tumor PDL1 expression as a continuous variable (% of positive PDL1 tumor cells) using the 5H1 antibody on archived tissues. We analyzed the correlation of PBC values with PDL1 expression as a continuous variable using a linear estimate. To evaluate the association of PBC values with RFS after adjusting for PDL1 expression, we employed multivariate Cox regression models. Results: A total of 706 ccRCC patients had available PDL1 expression and PBC. PDL1 expression was inversely associated with HGB (linear estimate of -0.02, p<0.001) and positively associated with platelets (linear estimate 1.73, p<0.001) whereas there was no association with PDL1 with WBC, ANC, AEC, or AMC. After adjusting for age and PDL1 expression, a higher HGB (HR=0.87, p<0.001), higher ALC (HR 0.68, p=0.003), and higher AEC (HR 0.12, p=0.002) were all associated with improved relapse free survival. Conversely, higher PLT was associated with decreased RFS (HR 1.002, p<0.001). Conclusions: PDL1 expression is associated with decreased HGB and increased PLT at the time of nephrectomy. After adjusting for PDL1 expression and age, higher HGB, ALC, and AEC are associated with improved RFS, while higher platelets are associated with decreased RFS.

Evaluation of post-operative complications and prolonged length of stay following cytoreductive nephrectomy

420

Background: Cytoreductive nephrectomy (CN) has been associated with significant morbidity, but there is little data identifying patients at increased risk. We evaluated the association of clinicopathologic features with early post-operative complications and prolonged length of stay (pLOS) among CN patients. Methods: We identified 294 patients treated with radical nephrectomy for M1 renal cell carcinoma between 1990 and 2009 at the Mayo Clinic. All complications within 30 days of surgery were reported using standardized methodology according to the Clavien classification. Associations with the presence of any early complication and pLOS (defined as ≥8 days, the top 25th percentile) were evaluated using logistic regression models. Results: Thirty-five (12%) patients experienced at least one early complication and 15 (5%) patients experienced at least one Clavien grade ≥3 early complication. The median LOS was 6 days (IQR 5-7), and 68 (23%) patients had a pLOS. On univariate analysis, liver metastases, symptomatic presentation, intraoperative transfusion, and pathologic nodal stage were significantly associated with both early complications and pLOS (Table). Two multivariate models were constructed. In Model 1 (limited to pre-operative features), only liver metastases (p<0.01) were associated with early complications while liver metastases (p=0.01) and open approach (p=0.02) were associated with pLOS. In Model 2 (all variables included), liver metastases (p=0.01), intraoperative transfusion (p<0.01), and high nuclear grade (p<0.01) were associated with early complications while intraoperative transfusion (p<0.01) and positive nodes (p=0.05) were associated with pLOS. Conclusions: CN was associated with a low incidence of early post-operative complications, particularly Clavien ≥3 complications. Presence of liver metastases and intraoperative transfusion were independently associated with increased risk of both complications and pLOS. [Table: see text]

The impact of rhabdoid differentiation on prognosis in patients with grade 4 renal cell carcinoma

494

Background: Renal cell carcinoma (RCC) with rhabdoid differentiation is thought to portend a poor prognosis, similar to RCC with sarcomatoid differentiation. Both rhabdoid and sarcomatoid differentiation are classified as grade 4 RCC based on the most recent International Society of Urological Pathology (ISUP) grading system. We sought to determine the prognostic value of rhabdoid differentiation in comparison to RCC with sarcomatoid differentiation, grade 4 RCC without rhabdoid or sarcomatoid differentiation, and grade 3 RCC. Methods: Using the Mayo Clinic Nephrectomy Registry, we identified 406 patients with ISUP grade 4 RCC and 1,758 patients with grade 3 RCC. A urologic pathologist reviewed all specimens to determine the presence of both rhabdoid and sarcomatoid differentiation. Associations of clinical and pathologic features with death from RCC were evaluated using Cox models. Results: Among the 406 grade 4 RCC tumors, 111 (27%) had rhabdoid differentiation and 189 (47%) had sarcomatoid differentiation, although only 28 (7%) demonstrated both rhabdoid and sarcomatoid differentiation. In multivariable analysis of grade 4 RCC tumors, the presence of rhabdoid differentiation was not associated with death from RCC (HR 0.95, p=0.75); in contrast, sarcomatoid differentiation was significantly associated with death from RCC (HR 1.63, p<0.001). Patients with RCC with rhabdoid differentiation were significantly more likely to die of RCC than patients with grade 3 RCC (HR 2.45, p<0.001) and grade 3 RCC with necrosis (HR 1.62; p<0.001). Conclusions: This study confirms that RCC with rhabdoid differentiation is appropriately classified as grade 4. However, unlike sarcomatoid differentiation, the presence of rhabdoid differentiation in grade 4 RCC is not associated with an increased risk of death from RCC. Therefore, rhabdoid and sarcomatoid differentiation should not be grouped together when assessing risk in a patient with grade 4 RCC.

Perioperative outcomes and hospital reimbursement by type of radical prostatectomy: results from a privately insured patient population

BACKGROUND

With the increasing use of robotic surgery in the United States, the comparative effectiveness and differences in reimbursement of minimally invasive radical prostatectomy (MIRP) and open prostatectomy (ORP) in privately insured patients are unknown. Therefore, we sought to assess the differences in perioperative outcomes and hospital reimbursement in a privately insured patient population who were surgically treated for prostate cancer.

METHODS

Using a large private insurance database, we identified 17,610 prostate cancer patients who underwent either MIRP or ORP from 2003 to 2010. The primary outcomes were length of stay (LOS), perioperative complications, 90-day readmissions rates and hospital reimbursement. Multivariable regression analyses were used to evaluate for differences in primary outcomes across surgical approaches.

RESULTS

Overall, 8981 (51.0%) and 8629 (49.0%) surgically treated prostate cancer patients underwent MIRP and ORP, respectively. The proportion of patients undergoing MIRP markedly rose from 11.9% in 2003 to 72.5% in 2010 (P<0.001 for trend). Relative to ORP, MIRP was associated with a shorter median LOS (1.0 day vs 3.0 days; P<0.001) and lower adjusted odds ratio of perioperative complications (OR: 0.82; P<0.001). However, the 90-day readmission rates of MIRP and ORP were similar (OR: 0.99; P=0.76). MIRP provided higher adjusted mean hospital reimbursement compared with ORP (US $19,292 vs. US $17,347; P<0.001).

CONCLUSIONS

Among privately insured patients diagnosed with prostate cancer, robotic surgery rapidly disseminated with over 70% of patients undergoing MIRP by 2009-2010. Although MIRP was associated with shorter LOS and modestly better perioperative outcomes, hospitals received higher reimbursement for MIRP compared with ORP.

Preoperative neutrophil-lymphocyte ratio predicts death among patients with localized clear cell renal carcinoma undergoing nephrectomy

OBJECTIVES

The neutrophil-lymphocyte ratio (NLR) is an indicator of the systemic inflammatory response. An increased pretreatment NLR has been associated with adverse outcomes in other malignancies, but its role in localized (M0) clear cell renal cell carcinoma (ccRCC) remains unclear. As such, we evaluated the ability of preoperative NLR to predict oncologic outcomes in patients with M0 ccRCC undergoing radical nephrectomy (RN).

METHODS AND MATERIALS

From 1995 to 2008, 952 patients underwent RN for M0 ccRCC. Of these, 827 (87%) had pretreatment NLR collected within 90 days before RN. Metastasis-free, cancer-specific, and overall survival was estimated using the Kaplan-Meier method and compared using the log-rank test. Multivariate models were used to analyze the association of NLR with clinicopathologic outcomes.

RESULTS

At a median follow-up of 9.3 years, 302, 233, and 436 patients had distant metastasis, death from ccRCC, and all-cause mortality, respectively. Higher NLR was associated with larger tumor size, higher nuclear grade, histologic tumor necrosis, and sarcomatoid differentiation (all, P < 0.001). A NLR ≥ 4.0 was significantly associated with worse 5-year cancer-specific (66% vs. 85%) and overall survival (66% vs. 85%). Finally, after controlling for clinicopathologic features, NLR remained independently associated with risks of death from ccRCC and all-cause mortality (hazard ratio for 1-unit increase: 1.02, P < 0.01).

CONCLUSIONS

Our results suggest that NLR is independently associated with increased risks of cancer-specific and all-cause mortality among patients with M0 ccRCC undergoing RN. Accordingly, NLR, an easily obtained marker of biologically aggressive ccRCC, may be useful in preoperative patient risk stratification.

AUA and NCCN surveillance guidelines for RCC: Do they effectively capture recurrences following nephrectomy?

402

Background: The American Urological Association (AUA) and the National Comprehensive Cancer Network (NCCN) are highly utilized sources for surveillance strategies following surgical treatment for renal cell carcinoma (RCC). However, the duration of follow-up may be inadequate to capture the majority of recurrences. Herein, we assess the ability of these guidelines to effectively capture recurrences of RCC following primary surgical resection. Methods: We reviewed our institutional database of 3,725 patients treated with radical or partial nephrectomy for M0 sporadic RCC between 1970-2008. For comparison to the AUA guidelines, patients were stratified into low risk following partial nephrectomy (LRp) or radical nephrectomy (LRr) = pT1N0, and moderate/high risk (M/HR) = pT2-4 N0-1. Guideline effectiveness was assessed by calculating the percentage of recurrences detected within the prescribed follow-up periods given for site-specific recurrence: AUA—LRp: 3yrs for all sites; LRr: 1yr for abdominal and 3yrs for chest/bone/other sites; M/HR: 5yrs for all sites; NCCN—6 months for abdominal/chest sites and 5yrs for bone/other sites. Results: Of the 3,725 patients, 2721 (73.1%) underwent radical nephrectomy, 2,210 (59.3%) were classified as pT1 NX-0 and 2,910 (78.1%) as clear cell RCC. Median postoperative follow-up was 8.9yrs (IQR 5.5-14.2) during which 1,114 (29.9%) patients developed recurrence. Of these recurrences, 760 (68.2%) would have been detected using the AUA guidelines and 432 (38.8%) by NCCN recommendations. Within AUA risk groups, 37.2% recurrences were captured in LRp, 31.4% in LRr and 80.2% in M/HR. Capture of 90% of recurrences in the abdomen and chest would require surveillance for 9yrs and 8 yrs, respectively in LRp, 15yrs and 12yrs in LRr and 11yrs and 10yrs in M/HR. Conclusions: Duration of follow-up recommended by current surveillance algorithms by the AUA and NCCN do not adequately capture many recurrences in RCC following radical or partial nephrectomy. Guidelines using risk stratification and site-specific recurrence parameters to assign length of surveillance may allow providers to better individualize surveillance regimens.

Temporal trends and factors associated with receipt of systemic therapy among patients undergoing cytoreductive nephrectomy

503

Background: We evaluated temporal patterns in the utilization of systemic therapy among patients undergoing cytoreductive nephrectomy (CN) for metastatic Renal Cell Carcinoma (mRCC) from a large national cancer registry and assessed patient characteristics associated with receipt of systemic treatment. Methods: We reviewed the National Cancer Database to identify patients with stage IV RCC who underwent CN between 1998-2010. Systemic therapy was defined as any treatment with immunotherapy and/or chemotherapy (including targeted agents). We evaluated the association between clinicopathologic features and receipt of systemic therapy using multivariable logistic regression with generalized estimating equations, and assessed the interaction of treatment with time, stratified as immunotherapy (1998-2004) versus targeted-therapy (2005-2010) eras. Results: Of 22,409 patients with mRCC undergoing CN, 8,830 (39%) received systemic therapy. Receipt of systemic therapy increased from 32% in 1998 to 49% in 2010 (p<0.001), largely due to increased utilization of chemotherapy (13.9% vs. 46.7%; p<0.001). Following adjustment, increasing patient age (51-60 years: OR 0.82 [CI 0.73-0.92]; 61-70 years: OR 0.67 [CI 0.59-0.76]; ≥71 years: OR 0.36 [CI 0.31-0.43]), as well as coverage with Medicaid (OR 0.61 [CI 0.5-0.74]), Medicare (OR 0.70 [CI 0.62-0.79]), or no insurance (OR 0.75 [CI 0.63-0.91]) were associated with decreased utilization of systemic therapy. Although use of systemic therapy in the elderly (≥71 years) and in patients with Medicare/Medicaid remained lower throughout the study period, each of these cohorts was significantly more likely to receive systemic treatment in the targeted versus immunotherapy era (all p values <0.05). Conclusions: Utilization of systemic therapy among patients undergoing CN has increased over time, coinciding with the introduction of targeted therapies. Nevertheless, still less than half of such patients receive systemic treatment. While the etiology for lack of treatment is likely multifactorial, the potential health policy implications of continued disparities in care warrant further investigation.

EAU and NCCN surveillance guidelines for bladder cancer: Do they effectively capture recurrences following cystectomy?

310

Background: The European Association of Urology (EAU) and the National Comprehensive Cancer Network (NCCN) provide general guidelines for bladder cancer (BC) surveillance following radical cystectomy (RC). However, it is unclear how well these guidelines capture recurrences after surgery. Herein, we assess the ability of current guidelines to effectively capture BC recurrence following RC and propose a risk stratified and recurrence site-specific surveillance strategy. Methods: We reviewed our institutional database of 1,800 patients who underwent primary RC between 1980-2007. Guideline effectiveness was assessed by calculating the percentage of recurrences detected within the prescribed follow-up periods: EAU—5yrs; NCCN—2yrs. Patients were then stratified according to stage: < = pT1Nx-0, > = pT2Nx-0, pN+, and recurrence site: urothelium, abdomen, chest, other. Recurrence free survival estimates for stage groups and recurrence site were assessed with Kaplan Meier models. Results: Of the 1,800 patients, 634 (35.2%) were classified as > pT2Nx-0 and 234 (13%) as pN+ and overall 228 (12.7%) received perioperative chemotherapy. Median postoperative follow-up was 10.6yrs (IQR 6.8-15.2), during which 716 (39.8%) patients developed recurrence. Of these recurrences, 492 (68.7%) would have been detected using the NCCN guidelines and 644 (89.8%) by EAU recommendations. However, ending oncologic surveillance at 5 years would only capture 81.7% of all recurrences for < = pT1Nx-0 patients and 83% of urothelial specific recurrences across all stage groups. Capture of 90% of recurrences, by stage group, in the urothelium, abdomen and chest would require surveillance for 8yrs, 8yrs and 4yrs, respectively in < = pT1Nx-0, 6yrs, 4yrs and 3yrs in > = pT2Nx-0 and 3yrs, 3yrs and 2yrs for pN+ patients. Conclusions: Duration of surveillance recommended for BC following RC by the EAU and NCCN do not comprehensively capture recurrences seen, specifically, in low risk patients and in cases of urothelial recurrence. Guidelines using risk stratification and site-specific recurrence patterns to assign length of surveillance may allow providers to better individualize surveillance regimens.

Validation of an inverse association between programmed death ligand 1 (PDL1) and genes in the vascular endothelial growth factor (VEGF) pathway in primary clear cell renal cell (ccRCC)

4567

Background: Trials combining anti-PDL1 and anti-VEGF therapies for clear cell renal cell carcinoma (ccRCC) are underway; however the relationship between the expression of PDL1 and genes in the VEGF pathway is poorly understood. Using the Affymetrix platform, we observed an inverse association between the expression of PDL1 and key genes in the VEGF pathway. Herein, we validate this inverse association using an independent set of 100 primary ccRCC tumors. Methods: From our registry database we sampled 100 ccRCC tumors with varying PDL1 protein expression (0%-100%) determined by immunohistochemistry (IHC). We extracted RNA from FFPE slides and performed RT-PCR to quantify gene expression of PDL1, VEGF, VEGFR1, and VEGFR2. All genes were normalized to the POLR2a gene. We evaluated the association of PDL1 protein expression and VEGF gene expression using Spearman rank correlation. In addition, we employed a linear mixed effects model to compare the fold-change in expression of VEGF genes between PDL1 low (0-5%, n=68) and PDL1 high (>5%, n=32) tumors. Results: As expected, PDL1 protein expression positively correlates with PDL1 geneexpression (corr=0.42, p<0.001). Validating our array data, PDL1 protein expression inversely correlates with expression of key VEGF genes: VEGF (corr=-0.23, p=0.01), VEGFR1 (corr=-0.34, p<0.001), and VEGFR2 (corr=-0.23, p=0.01). In our dichotomized analysis, we noted significantly higher expression of VEGF genes in the PDL1 low compared to the PDL1 high group: VEGF (fold change=1.82, p<0.001), VEGFR1 (FC=2.63, p<0.001), and VEGFR2 (FC=2.13, p=0.001). Conclusions: We independently validate an inverse association between the expression of PDL1 and key genes in the VEGF pathway in primary ccRCC. If validated further in larger studies, the existence of an immune evasive and an angiogenic phenotype within ccRCC could inform current clinical trials targeting these two pathways. Ultimately, whether VEGF signaling affects PDL1 expression, or whether angiogenic or immune evasive phenotypes predict response to anti-PDL1, anti-VEGF, or a combination of the two therapies remains unclear.

Outcomes of patients with sarcomatoid renal cell carcinoma: The Mayo Clinic experience

359

Background: Sarcomatoid renal cell carcinoma (RCC) is an aggressive form of RCC and is associated with a poor prognosis. Standard therapies tend to be less effective in this subset of patients. Methods: Using the Mayo Clinic Nephrectomy Registry, 206 patients with sarcomatoid RCC treated with partial or radical nephrectomy were identified. These patients were characterized based on extent of disease, treatment response and survival. Results: Of these 206, there was no evidence of distant metastases in 110 patients at the time of surgery and the estimated distant metastases-free survival at one year was 44%. The estimated cancer-specific survival rate at one and five years was 56% and 20%, respectively. Compared to patients with grade 4 RCC without sarcomatoid features, those with sarcomatoid RCC were more likely to develop distant metastases following surgery (hazard ratio 1.49). Considering those with metastatic sarcomatoid RCC, 96 patients had metastases at the time of surgery and 77 with no metastases at the time of surgery subsequently developed distant metastases (n=173). Of these, 156 died at a mean of 1.0 years from time of first evidence of distant metastases with a median cancer-specific survival of 0.6 years. Estimated cancer-specific survival rates from time of first metastases at one year and five years were 34% and 4%, respectively. The most common metastatic sites: lung (46%), bone (15%), liver (13%), non-regional lymph nodes (9%), and brain (5%). Patients who received targeted systemic therapy (10%) with either sunitinib (n=14), sorafenib (2) or pazopanib (1) for their first occurrence of distant metastases had an estimated cancer-specific survival rate at one year of 69%, compared to 30% for patients who did not. Median cancer-specific survival for those receiving targeted therapy as first-line was 2.2 years compared to 0.6 years for those patients who did not. Conclusions: Sarcomatoid RCC is an aggressive subtype of kidney cancer as evidenced by poor survival rates. The patients in this registry with metastatic sarcomatoid RCC who received targeted therapy as first-line treatment had improved cancer-specific survival rates.

PRODUCTION OF EXPERIMENTAL OSTEOMYELITIS IN RABBITS BY INTRAVENOUS INJECTION OF STAPHYLOCOCCUS AUREUS

1. The conditions under which a certain strain of staphylococcus (OH 172) causes in rabbits the development of bone inflammation have been described. 2. The virulence of the strain for rabbits was markedly raised by passage through this animal species, and especially after the culture had been recovered from a bone abscess. 3. The results indicate that it is possible to produce consistently inflammation of the bones of rabbits by the mere intravenous injection of a suitable strain of staphylococcus, without resorting to any elaborate operative technique designed to localize the organisms in the bones. It appears also that the inflammatory process so produced bears a close resemblance to staphylococcal osteomyelitis as occurring in human beings.

Patients With pT1 Renal Cell Carcinoma Who Die From Disease After Nephrectomy May Have Unrecognized Renal Sinus Fat Invasion

Prior studies suggest that the renal sinus permits early tumor spread in otherwise localized renal cell carcinoma (RCC) tumors. We hypothesized that renal sinus fat invasion may be unrecognized in pT1 patients who subsequently die from RCC. Between 1985 and 2002, we identified 577 patients who underwent radical nephrectomy for localized pT1 clear cell RCC as reviewed by a single urologic pathologist (J.C.C.). Among these patients, 49 died from RCC including 33 who had their original nephrectomy specimen stored in formalin. These specimens were then resectioned with thin cuts of the renal sinus and reviewed by the same pathologist. For comparison, 33 patients who did not die from RCC (controls) also had their original nephrectomy specimen resectioned. Among the 33 patients who died from seemingly localized RCC, 14 (42%) had previously unrecognized renal sinus fat invasion compared with 2 (6%) of the controls (P<0.001). In addition, 19 (58%) patients who died from RCC had renal sinus small vein (microscopic venous) invasion, a pathologic feature not currently incorporated into the TNM staging system for RCC. This feature was present in 7 (21%) of the controls (P=0.003). In total, 22 (67%) patients who died from RCC had unrecognized renal sinus fat or small vein invasion compared with 7 (21%) of the controls (P<0.001). We conclude that renal sinus fat invasion is an important adverse pathologic feature that is clearly underreported in the literature. Appropriate assessment of nephrectomy specimens should include proper sampling of the renal sinus even for seemingly localized tumors.