A generative adversarial approach to facilitate archival-quality histopathologic diagnoses from frozen tissue sections.

In clinical diagnostics and research involving histopathology, formalin-fixed paraffin-embedded (FFPE) tissue is almost universally favored for its superb image quality. However, tissue processing time (>24 h) can slow decision-making. In contrast, fresh frozen (FF) processing (<1 h) can yield rapid information but diagnostic accuracy is suboptimal due to lack of clearing, morphologic deformation and more frequent artifacts. Here, we bridge this gap using artificial intelligence. We synthesize FFPE-like images ("virtual FFPE") from FF images using a generative adversarial network (GAN) from 98 paired kidney samples derived from 40 patients. Five board-certified pathologists evaluated the results in a blinded test. Image quality of the virtual FFPE data was assessed to be high and showed a close resemblance to real FFPE images. Clinical assessments of disease on the virtual FFPE images showed a higher inter-observer agreement compared to FF images. The nearly instantaneously generated virtual FFPE images can not only reduce time to information but can facilitate more precise diagnosis from routine FF images without extraneous costs and effort.

Hybrid oncocytic/chromophobe renal tumors are molecularly distinct from oncocytoma and chromophobe renal cell carcinoma.

Hybrid oncocytic/chromophobe tumor (HOCT) of the kidney represents a poorly understood clinicopathologic entity with pathologic features that overlap between benign renal oncocytoma (RO) and malignant chromophobe renal cell carcinoma (ChRCC). Consequently, characterization of HOCT and its separation from the foregoing entities are clinically important. The aim of this study was to describe the pathologic and molecular features of HOCT and to compare them with those of RO and ChRCC. We retrospectively identified a cohort of 73 cases with renal oncocytic tumors (19 RO, 27 HOCT, and 27 ChRCC) for whom clinical follow-up data were available by 2 tertiary care hospitals. All cases were sporadic except for 2 HOCTs that were associated with Birt-Hogg-Dubé syndrome. Lesional tissues were retrieved for molecular analysis. We performed targeted gene sequencing of all exons of 261 cancer related genes on a subset of HOCT samples (n = 16). Gene expression profiling of a customized codeset was conducted on 19 RO, 24 HOCT, and 27 ChRCC samples. Clinicopathologic characteristics as well as DNA copy number alterations, mutational and transcriptional features of HOCT derived from sequencing and expression profiling data are described and compared to those in RO and ChRCC. HOCTs were more frequently multifocal and did not exhibit mutations in genes that are recurrently mutated in RO or ChRCC but showed copy number alterations primarily involving losses in chromosomes 1 and X/Y. The mRNA transcript data show that HOCT can be separated from RO and ChRCC. Hence, HOCT appears to represent a distinct renal tumor entity with genomic features that are intermediate between those of RO and ChRCC.

Renal cell carcinoma and pathologic nodal disease: Implications for American Joint Committee on Cancer staging.

BACKGROUND: Lymph node (LN) metastases are associated with poor outcomes for patients with renal cell carcinoma (RCC). This study compared the survival outcomes of patients with stage III, node-positive disease (pT123 N1 M0 ) and patients with stage III, node-negative disease (pT3 N0 M0 ). METHODS: A database of 4652 patients with RCC of any histological subtype treated with surgery at The University of Texas MD Anderson Cancer Center from 1993 to 2012 was retrospectively assessed. A total of 115 patients with pT123 N1 M0 disease, 274 patients with pT3 N0 M0 disease, and 523 patients with pT123 N0/x M1 disease were included. Overall survival (OS) and cancer-specific survival (CSS) were estimated and compared between each cohort. RESULTS: Median OS and CSS times were significantly better for pT3 N0 M0 patients than pT123 N1 M0 patients (OS, 10.2 vs 2.4 years, P < .0001; CSS, not reached vs 2.8 years, P < .0001). Similar median OS and CSS times were noted for pT123 N1 M0 and pT123 N0/x M1 patients (OS, 2.4 vs 2.4 years; P = .62; CSS, 2.8 vs 2.4 years; P = .10). In a multivariate analysis, tumor grade (hazard ratio [HR] for OS, 2.47; P < .0001; HR for CSS, 2.99; P < .0001) and pathologic LN involvement (HR for OS, 2.44; P < .0001; HR for CSS, 2.85; P < .0001) were associated with worse OS and CSS. CONCLUSIONS: Among RCC patients classified with stage III disease, those with pT123 N1 M0 disease had significantly worse survival than those with pT3 N0 M0 disease. OS and CSS were similar for patients with pT123 N1 M0 disease and patients with pT123 N0/x M1 disease (stage IV). If validated, these findings suggest that RCC patients with nodal disease should be reclassified as having stage IV disease.

Local Tumor Bed Recurrence Following Partial Nephrectomy in Patients with Small Renal Masses.

PURPOSE: We examined the incidence, characteristics and treatment of patients with tumor bed recurrence after partial nephrectomy. MATERIALS AND METHODS: We retrospectively reviewed the charts of 2,256 patients with sporadic small renal masses treated with partial nephrectomy between 2000 and 2014. Local tumor bed recurrence was strictly defined as detection of a new enhancing lesion 1) specifically in the surgical defect or 2) in the same region (eg lower pole) as the partial nephrectomy site. To determine differences in multiple characteristics 44 patients (1.9%) with local recurrence were compared to 163 randomly selected patients who underwent partial nephrectomy with no recurrence. RESULTS: Patients with local tumor bed recurrence were more likely to have a solitary kidney (27% vs 4%, p <0.01) and bilateral disease at presentation (23% vs 10.4%, p = 0.02) compared to the group with no recurrence. Positive margins were found in 15.9% of local tumor bed recurrences compared to 3% of the control group (p <0.01). Median time between partial nephrectomy and the detection of local tumor bed recurrence was 23 months (range 2 to 107). Male gender, a solitary kidney at partial nephrectomy, positive surgical margins, multiple tumors, and higher nephrometry score and pathological stage were associated with local tumor bed recurrence. CONCLUSIONS: Local tumor bed recurrence after partial nephrectomy is associated with several preoperative factors, including multiple tumors and a solitary kidney, as well as intraoperative and postoperative factors such as a positive surgical margin and higher pathological stage.

Oncologic outcomes of patients with positive surgical margin after partial nephrectomy: a 25-year single institution experience.

PURPOSE: To evaluate oncologic outcomes and management of patients with microscopic positive surgical margin (PSM) after partial nephrectomy (PN) for renal cell carcinoma (RCC). METHODS: We reviewed our database to identify patients who underwent PN between 1990 and 2015 for RCC and had PSM on final pathology. A 1:3 matching was performed to a negative surgical margin (NSM) cohort. Kaplan-Meier method and log-rank test were used to estimate survival and differences in outcomes, respectively. Cox proportional hazards models were conducted to estimate the Hazards ratio. RESULTS: A total of 2297 patients underwent PN at our institution, of which 1863 (81%) had RCC. Microscopic PSM was found in 34 (1.8%) RCC patients who were matched to 100 patients with NSM. Of these 34 patients, local recurrence (n = 4), distant kidney recurrences (n = 4), and metastases (n = 5) developed during a median follow-up of 62 months. Bilateral tumors/tumors in a solitary kidney (n = 12/13, 92%), and multifocal tumors (n = 7/13, 54%) were found in patients who developed recurrence/metastasis. PSM patients were at a higher risk of shorter overall survival (p = 0.001), local recurrence-free survival (p = 0.003), distant recurrence-free survival (p = 0.032) and metastasis-free survival (p = 0.018). There was statistically significant association between PSM and bilateral tumors, prior treated RCC at presentation and higher nephrometry score in multivariable model. CONCLUSIONS: There was a low rate of microscopic PSM in our large cohort of patients undergoing PN despite tumor complexity. Higher nephrometry score, bilateral tumors, and prior treated RCC independently predicted PSM which showed worse survival, recurrence and metastasis compared to patients with NSM.

Programmed cell death ligand 1 and tumor-infiltrating lymphocyte status in patients with renal cell carcinoma and sarcomatoid dedifferentiation.

BACKGROUND: The immune profile of sarcomatoid renal cell carcinoma (sRCC), including the programmed cell death ligand 1 (PD-L1) and programmed cell death 1 (PD-1) status, has not been well characterized. METHODS: An immunohistochemical digital analysis of PD-L1, PD-1, CD4, and CD8 was performed on nephrectomy specimens from 118 sRCC patients and 92 nonsarcomatoid clear cell renal cell carcinoma (ccRCC) patients. The clinical characteristics of the population were compared between sRCC and ccRCC. Overall survival was estimated, and comparisons were made between PD-L1-positive and PD-L1-negative groups as well as tumor-infiltrating lymphocyte (TIL)-high and TIL-low groups. RESULTS: The PD-L1 H-score of sRCC (mean, 3.7; range, 0-192.1) was significantly higher than the score of grade 4 ccRCC (P = .001), and 41.3% of sRCC cases showed a PD-L1 H-score ≥ 10. The PD-1-positive cell density was significantly higher in sRCC versus ccRCC within the tumor and at the invasive front. The intratumoral CD8-positive cell density was significantly higher in sRCC versus ccRCC. Forty-one percent in the sarcomatoid component of sRCC and 8% in the epithelioid component of sRCC had an adaptive immune resistance phenotype (PD-L1-positive and TIL-positive), whereas only 1% in ccRCC had the type I phenotype. CONCLUSIONS: sRCC showed higher PD-L1 expression and higher PD-1- and CD8-positive cell density than grade 4 ccRCC. The results indicate a notable immunosuppressive environment in sRCC. Despite advances in the treatment of advanced-stage renal cell carcinoma, sRCC still has a poor prognosis. This work describes highly immunosuppressive characteristics of sRCC in comparison with an appropriate ccRCC control. The results suggest PD-1/PD-L1 blockade therapy as a potential therapeutic approach for sRCC. Cancer 2017;123:4823-31. © 2017 American Cancer Society.

Molecular Subtypes Improve Prognostic Value of International Metastatic Renal Cell Carcinoma Database Consortium Prognostic Model.

INTRODUCTION: Gene-expression signatures for prognosis have been reported in localized renal cell carcinoma (RCC). The aim of this study was to test the predictive power of two different signatures, ClearCode34, a 34-gene signature model [Eur Urol 2014;66:77-84], and an 8-gene signature model [Eur Urol 2015;67:17-20], in the setting of systemic therapy for metastatic disease. MATERIALS AND METHODS: Metastatic RCC (mRCC) patients from five institutions who were part of TCGA were identified and clinical data were retrieved. We trained and implemented each gene model as described by the original study. The latter was demonstrated by faithful regeneration of a figure and results from the original study. mRCC patients were dichotomized to good or poor prognostic risk groups using each gene model. Cox proportional hazard regression and concordance index (C-Index) analysis were used to investigate an association between each prognostic risk model and overall survival (OS) from first-line therapy. RESULTS: Overall, 54 patients were included in the final analysis. The primary endpoint was OS. Applying the ClearCode34 model, median survival for the low-risk-ccA (n = 17)-and the high-risk-ccB (n = 37)-subtypes were 27.6 and 22.3 months (hazard ratio (HR): 2.33; p = .039), respectively. ClearCode34 ccA/ccB and International Metastatic Renal Cell Carcinoma Database Consortium (IMDC) classifications appear to represent distinct risk criteria in mRCC, and we observed no significant overlap in classification (p > .05, chi-square test). On multivariable analyses and adjusting for IMDC groups, ccB remained independently associated with a worse OS (p = .044); the joint model of ccA/ccB and IMDC was significantly more accurate in predicting OS than a model with IMDC alone (p = .045, F-test). This was also observed in C-Index analysis; a model with both ccA and ccB subtypes had higher accuracy (C-Index 0.63, 95% confidence interval [CI] = 0.51-0.75) and 95% CIs of the C-Index that did not include the null value of 0.5 in contrast to a model with IMDC alone (0.60, CI = 0.47-0.72). The 8-gene signature molecular subtype model was a weak but insignificant predictor of survival in this cohort (p = .13). A model that included both the 8-gene signature and IMDC (C-Index 0.62, CI = 0.49-0.76) was more prognostic than IMDC alone but did not reach significance, as the 95% CI included the null value of 0.5. These two genomic signatures share no genes in common and are enriched in different biological pathways. The ClearCode34 included genes ARNT and EPAS1 (also known as HIF2a), which are involved in regulation of gene expression by hypoxia-inducible factor. CONCLUSION: The ClearCode34 but not the 8-gene molecular model improved the prognostic predictive power of the IMDC model in this cohort of 54 patients with metastatic clear cell RCC. The Oncologist 2017;22:286-292 IMPLICATIONS FOR PRACTICE: The clinical and laboratory factors included in the International Metastatic Renal Cell Carcinoma Database Consortium model provide prognostic information in metastatic renal cell carcinoma (mRCC). The present study shows that genomic signatures, originally validated in localized RCC, may add further complementary prognostic information in the metastatic setting. This study may provide new insights into the molecular basis of certain mRCC subgroups. The integration of clinical and molecular data has the potential to redefine mRCC classification, enhance the understanding of mRCC biology, and potentially predict response to treatment in the future.

Study of the Kidney Tumor-Parenchymal Interface after Neoadjuvant Treatment with Axitinib for Locally Advanced Clear Cell Renal Cell Carcinoma: Matched Analysis from a Phase II Trial.

PURPOSE: The aim of this study was to evaluate histological changes in the tumor-parenchymal interface in clear cell renal cell carcinoma after neoadjuvant axitinib treatment. MATERIALS AND METHODS: We obtained clinical and pathology materials from 23 patients with clear cell renal cell carcinoma treated with neoadjuvant axitinib in a phase II clinical trial and from 23 matched patients with clear cell renal cell carcinoma who underwent upfront surgery. Histology of the tumor pseudocapsule and the peritumor kidney parenchymal change was evaluated and compared between the 2 cohorts. RESULTS: A tumor pseudocapsule was noted in all 23 patients who received neoadjuvant axitinib and in all 23 control patients. Most pseudocapsules were noncontinuous and only partially covered the tumor, including in 17 of 23 axitinib cases (74%) and 19 of 23 controls (83%). In axitinib cases the median thickness of the intrarenal and extrarenal pseudocapsule was 1.4 and 2.4 mm, respectively, which was significantly thicker than in control cases (intrarenal p = 0.0008 and extrarenal p <0.0001). The thickness of the pseudocapsule in axitinib treated cases was more frequently irregular compared to that in controls (16 of 23 or 70% and 9 of 23 or 39%, respectively, p = 0.0746). Inflammation, nephrosclerosis, glomerulosclerosis and arteriosclerosis decreased with increasing distance from the tumor edge in the neoadjuvant axitinib and control groups. CONCLUSIONS: The tumor pseudocapsule becomes irregularly thick after neoadjuvant axitinib therapy. Although axitinib likely evokes a strong fibrous reaction in the tumor-parenchymal interface, it does not affect the frequency of infiltrative tumor invasion to the outside of the pseudocapsule or the degree of atrophic/inflammatory change in tissue surrounding the tumor. These findings support the notion that partial nephrectomy could be safely done in well selected patients after neoadjuvant axitinib.

Outcomes of Patients with Renal Cell Carcinoma and Sarcomatoid Dedifferentiation Treated with Nephrectomy and Systemic Therapies: Comparison between the Cytokine and Targeted Therapy Eras.

PURPOSE: We studied overall survival and prognostic factors in patients with sarcomatoid renal cell carcinoma treated with nephrectomy and systemic therapy in the cytokine and targeted therapy eras. MATERIALS AND METHODS: This is a retrospective study of patients with sarcomatoid renal cell carcinoma who underwent nephrectomy and received systemic therapy at our center in the cytokine era (1987 to 2005) or the targeted therapy era (2006 to 2015). Multivariate regression models were used to determine the association of covariables with survival. RESULTS: Of the 199 patients with sarcomatoid renal cell carcinoma 167 (83.9%) died (median overall survival 16.5 months, 95% CI 15.2-20.9). Survival of patients with clear cell histology was significantly longer vs those with nonclear cell histology (p = 0.034). Patients with synchronous metastatic disease had significantly shorter survival than patients with metachronous metastatic disease (median 12.1 vs 23.3 months, p = 0.0064). Biopsy of the primary tumor or a metastatic site could detect the presence of sarcomatoid features in only 7.5% of cases. Although a significant improvement in survival rate was observed in the first year in patients treated in the targeted therapy era (p = 0.011), this effect was attenuated at year 2, disappeared at years 3 to 5 after diagnosis and was not evident in patients with poor risk features. CONCLUSIONS: Patients with sarcomatoid renal cell carcinoma still have poor prognosis with no clear long-term benefit of targeted therapy. This underscores the need to develop more effective systemic therapies for these patients.

Factors associated with regional recurrence after lymph node dissection for penile squamous cell carcinoma.

OBJECTIVE: To identify factors associated with regional recurrence after lymph node dissection (LND) for squamous cell carcinoma (SCC) to determine which patients might benefit from adjuvant therapy. PATIENTS AND METHODS: Men who underwent LND for penile SCC from 1977 to 2014 were identified from an institutional database. Kaplan-Meier curves estimated recurrence-free survival (RFS) calculated from the date of LND. Cox regression models evaluated the association between RFS and patient and tumour characteristics. RESULTS: In all, 182 men who underwent LND for penile SCC were identified. The median patient age was 62 years and the median follow-up was 4.2 years. After LND 34 men had regional recurrence, of which 24 developed isolated regional recurrences without distant metastasis. The median RFS was 5.7 months, and the 3-year RFS rate was 70%. On univariate analysis, lymphovascular invasion, clinical and pathological nodal stage, pathological inguinal laterality, pelvic nodal involvement, lymph node density ≥5.2%, ≥3 pathologically involved lymph nodes, and extranodal extension (ENE) were associated with worse RFS (all P < 0.05). On multivariate analysis, clinical N3 disease [adjusted hazard ratio (AHR)] 3.53, 95% confidence interval (CI) 1.68-7.45; P = 0.001), ≥3 pathologically involved lymph nodes (AHR 3.78, 95% CI 2.12-6.65; P < 0.001), and ENE (AHR 3.32, 95% CI 1.93-5.76; P < 0.001) were associated with worse RFS. The 3-year RFS for patients with cN0, cN1, cN2, and cN3 disease was 91.7%, 64.5%, 54.7%, and 38.3%, respectively. For men with ≥3 involved nodes, the 3-year RFS was 17% vs 82.4% in men with <3 involved nodes. The 3-year RFS was 29.7% in men with ENE and 85.7% in men without ENE. CONCLUSION: The presence of clinical N3 disease, ≥3 pathologically involved lymph nodes, and ENE was associated with worse RFS. As regional recurrence portends a dismal prognosis with few salvage options, adjuvant therapies should be developed for men with the aforementioned adverse factors.

Management and outcomes of patients with renal medullary carcinoma: a multicentre collaborative study.

OBJECTIVE: To describe the management strategies and outcomes of patients with renal medullary carcinoma (RMC) and characterise predictors of overall survival (OS). PATIENTS AND METHODS: RMC is a rare and aggressive malignancy that afflicts young patients with sickle cell trait; there are limited data on management to date. This is a study of patients with RMC who were treated in 2000-2015 at eight academic institutions in North America and France. The Kaplan-Meier method was used to estimate OS, measured from initial RMC diagnosis to date of death. Cox regression analysis was used to determine predictors of OS. RESULTS: In all, 52 patients (37 males) were identified. The median (range) age at diagnosis was 28 (9-48) years and 49 patients (94%) had stage III/IV. The median OS for all patients was 13.0 months and 38 patients (75%) had nephrectomy. Patients who underwent nephrectomy had superior OS compared to patients who were treated with systemic therapy only (median OS 16.4 vs 7.0 months, P < 0.001). In all, 45 patients received chemotherapy and 13 (29%) had an objective response; 28 patients received targeted therapies, with 8-week median therapy duration and no objective responses. Only seven patients (13%) survived for >24 months. CONCLUSIONS: RMC carries a poor prognosis. Chemotherapy provides palliation and remains the mainstay of therapy, but <20% of patients survive for >24 months, underscoring the need to develop more effective therapy for this rare tumour. In this study, nephrectomy was associated with improved OS.

The Role of Metastasectomy in Patients with Renal Cell Carcinoma with Sarcomatoid Dedifferentiation: A Matched Controlled Analysis.

PURPOSE: Management of metastatic renal cell carcinoma with sarcomatoid dedifferentiation remains a therapeutic challenge with no standard treatment strategies. We evaluated whether metastasectomy has any survival benefit in patients with metastatic sarcomatoid dedifferentiation treated with radical nephrectomy. MATERIALS AND METHODS: From an institutional database of 273 patients with sarcomatoid dedifferentiation treated with nephrectomy we matched 80 with synchronous and asynchronous metastases for age, ECOG (Eastern Cooperative Oncology Group) performance status, histology and lymph node status. Matched pairs were then retained only if patients who did not undergo metastasectomy were alive at metastasectomy comparable to matched surgical patients to decrease the bias of survival outcomes. Overall survival from nephrectomy was studied using univariable and multivariable proportional hazards regression. RESULTS: Median overall survival was 8.3 (95% CI 6.5-10.5) and 18.5 months (95% CI 11.5-42.9) in patients with synchronous and asynchronous metastases, respectively. Overall survival in patients who underwent metastasectomy for synchronous metastasis compared to nonsurgical patients was 8.4 and 8.0 months (p = 0.35), respectively. Similarly, overall survival in patients with asynchronous metastases treated with metastasectomy compared to the nonsurgical group was 36.2 and 13.7 months, respectively (p = 0.29). On multivariable analysis positive lymph nodes at nephrectomy were associated with an increased risk of death in the synchronous and asynchronous patient subgroups (HR 2.1, 95% CI 1.1-4.0, p = 0.03 and HR 3.3, 95% CI 1.2-9.2, p = 0.02, respectively). CONCLUSIONS: In the current study there was no clear evidence of benefit in patients with sarcomatoid dedifferentiation who underwent metastasectomy after nephrectomy. Particularly, the group of patients with pathological lymph node positive disease at nephrectomy had considerably worse survival.

Metastases to the kidney: a comprehensive analysis of 151 patients from a tertiary referral centre.

OBJECTIVE: To describe the presentation, treatment and outcomes of patients with metastatic tumours to the kidney treated at a tertiary referral centre. PATIENTS AND METHODS: We retrospectively identified 151 patients diagnosed with a primary non-renal malignancy with renal metastasis. Clinical, radiographic and pathological characteristics were assessed. Overall survival (OS) was calculated using Kaplan-Meier methods. RESULTS: The median patient age was 56.7 years. The most common presenting symptoms were flank pain (30%), haematuria (16%) and weight loss (12%). Most primary cancers were carcinomas (80.8%). The most common primary tumour sites were lung (43.7%), colorectal (10.6%), head and neck (6%), breast (5.3%), soft tissue (5.3%) and thyroid (5.3%). Renal metastases were typically solitary (77.5%). Concordance between radiologist and clinician imaging assessment was 54.0%. Three ablations and 48 nephrectomies were performed. For non-surgical patients, renal metastasis diagnosis was made with fine-needle aspiration or biopsy. The median OS from primary tumour diagnosis was 3.08 years and the median OS from time of metastatic diagnosis was 1.13 years. For patients treated with surgery, median OS from primary tumour diagnosis was 4.81 years, and OS from metastatic diagnosis was 2.24 years. CONCLUSIONS: Metastases to the kidney are a rare entity. Survival appears to be longer in patients who are candidates for and are treated with surgery. Surgical intervention in carefully selected patients with oligometastatic disease and good performance status should be considered. A multidisciplinary approach with input from urologists, oncologists, radiologists and pathologists is needed to achieve the optimum outcomes for this specific patient population.

Prognosis of patients with metastatic renal cell carcinoma and pancreatic metastases.

OBJECTIVES: To identify the clinical outcomes of patients with metastatic renal cell carcinoma (mRCC) with pancreatic metastases (PM) treated with either pazopanib or sunitinib and assess whether PM is an independent prognostic variable in the current therapeutic environment. PATIENTS AND METHODS: A retrospective review of patients with mRCC in an outpatient clinic was carried out for the period January 2006 to November 2011. Patient characteristics, including demographics, laboratory data and outcomes, were analysed. Baseline characteristics were compared using chi-squared and t-tests and overall survival (OS) and cancer-specific survival (CSS) rates were estimated using Kaplan-Meier methods. Predictors of OS were analysed using Cox regression. RESULTS: A total of 228 patients were reviewed, of whom 44 (19.3%) had PM and 184 (81.7%) had metastases to sites other than the pancreas. The distribution of baseline characteristics was equal in both groups, with the exception of a higher incidence of previous nephrectomy, diabetes and number of metastatic sites in the PM group. Four patients had isolated PM, but the majority of patients (68%) with PM had at least three different organ sites of metastases, as compared with 29% in patients without PM (P < 0.01). The distribution of organ sites of metastases was similar, excluding the pancreas, in those with and those without PM (P > 0.05). The median OS was 39 months (95% confidence interval [CI] 24-57, hazard ratio 0.66, 95% CI 0.42-0.94; P = 0.02) for patients with PM, compared with 26 months (95% CI 21-31) for patients without PM (P < 0.01). CSS was 42 months (95% CI 30-57) in the PM group and 27 months (95% CI 22-33) in the control group (P = 0.05). CONCLUSIONS: Despite a higher number of affected organ sites in the PM cohort, mRCC behaviour in this cohort appears to be more indolent, as demonstrated by a higher median OS. These findings suggest that host or tumour features associated with PM may represent a less aggressive tumour phenotype.

Intratumoral morphologic and molecular heterogeneity of rhabdoid renal cell carcinoma: challenges for personalized therapy.

Rhabdoid histology in clear-cell renal cell carcinoma is associated with a poor prognosis. The prognosis of patients with clear-cell renal cell carcinoma may also be influenced by molecular alterations. The aim of this study was to evaluate the association between histologic features and salient molecular changes in rhabdoid clear-cell renal cell carcinoma. We macrodissected the rhabdoid and clear-cell epithelioid components from 12 cases of rhabdoid clear-cell renal cell carcinoma. We assessed cancer-related mutations from eight cases using a clinical next-generation exome-sequencing platform. The transcriptome of rhabdoid clear-cell renal cell carcinoma (n=8) and non-rhabdoid clear-cell renal cell carcinoma (n=37) was assessed by RNA-seq and gene expression microarray. VHL (63%) showed identical mutations in all regions from the same tumor. BAP1 (38%) and PBRM1 (13%) mutations were identified in the rhabdoid but not in the epithelioid component and were mutually exclusive in 3/3 cases and 1 case, respectively. SETD2 (63%) mutations were discordant between different histologic regions in 2/5 cases, with mutations called only in the epithelioid and rhabdoid components, respectively. The transcriptome of rhabdoid clear-cell renal cell carcinoma was distinct from advanced-stage and high-grade clear-cell renal cell carcinoma. The diverse histologic components of rhabdoid clear-cell renal cell carcinoma, however, showed a similar transcriptomic program, including a similar prognostic gene expression signature. Rhabdoid clear-cell renal cell carcinoma is transcriptomically distinct and shows a high rate of SETD2 and BAP1 mutations and a low rate of PBRM1 mutations. Driver mutations in clear-cell renal cell carcinoma are often discordant across different morphologic regions, whereas the gene expression program is relatively stable. Molecular profiling of clear-cell renal cell carcinoma may improve by assessing for gene expression and sampling tumor foci from different histologic regions.

Surgical Management of Local Retroperitoneal Recurrence of Renal Cell Carcinoma after Radical Nephrectomy.

PURPOSE: Isolated local retroperitoneal recurrence after radical nephrectomy for renal cell carcinoma poses a therapeutic challenge. We investigated outcomes in patients with localized retroperitoneal recurrence treated with surgical resection. MATERIALS AND METHODS: This was a retrospective, single institutional study of 102 patients with retroperitoneal recurrence treated with surgery from 1990 to 2014. Demographics, clinical and pathological features, location of retroperitoneal recurrence and perioperative complications are reported using descriptive statistics. We studied recurrence-free and cancer specific survival using univariate and multivariate analyses. RESULTS: Median age at retroperitoneal recurrence diagnosis was 55 years (IQR 49-64). Cancer was pT3-4 in 62 patients (60.8%) and pN1 in 20 (19.6%). No patients had distant metastatic disease at retroperitoneal recurrence surgery. Median time from nephrectomy to retroperitoneal recurrence diagnosis was 19 months (IQR 5-38.8). The median size of the resected retroperitoneal recurrence was 4.5 cm (IQR 2.7-7). Median followup after recurrence surgery was 32 months (IQR 16-57). Metastatic progression was observed in 60 patients (58.8%) postoperatively. Neoadjuvant and salvage systemic therapy was administered in 46 (45.1%) and 48 patients (47.1%), respectively. On multivariate analysis pathological nodal stage at original nephrectomy and maximum diameter of retroperitoneal recurrence were identified as independent risk factors for cancer specific death. CONCLUSIONS: Clinicopathological factors at nephrectomy as well as retroperitoneal recurrence surgery are important prognosticators. Aggressive surgical resection offers potential cure in a substantial number of patients with retroperitoneal recurrence with acceptable complications and still has a dominant role in the management of isolated locally recurrent RCC.

Preoperative predictors of pathological lymph node metastasis in patients with renal cell carcinoma undergoing retroperitoneal lymph node dissection.

PURPOSE: Patients with locally advanced renal cell carcinoma represent a subset that may benefit from retroperitoneal lymph node dissection. We identified preoperative clinical predictors of positive lymph nodes in patients with renal cell carcinoma without distant metastasis who underwent retroperitoneal lymph node dissection. MATERIALS AND METHODS: We retrospectively analyzed data on a consecutive cohort of 1,270 patients with cTany Nany M0 renal cell carcinoma who were treated at a single institution from 1993 to 2012. Multivariate analysis was performed to determine preoperative predictors of pathologically positive lymph nodes in patients who underwent retroperitoneal lymph node dissection. A nomogram was developed to predict the probability of lymph node metastasis. Overall, cancer specific and recurrence-free survival was estimated using the Kaplan-Meier Method. RESULTS: We identified 1,270 patients with renal cell carcinoma without distant metastasis who had (564) or did not have (706) retroperitoneal lymph node dissection performed. Of the 564 patients 131 (23%) and 433 (77%) had pN1 and pN0 disease, and 60 (37%) and 29 (7.2%) had cN1pN0 and cN0pN1 disease, respectively. ECOG PS, cN stage, local symptoms and lactate dehydrogenase were associated with nodal metastasis on multivariable analysis. A nomogram was developed with a C-index of 0.89 that demonstrated excellent calibration. Differences in overall, cancer specific and recurrence-free survival among pNx, pN0 and pN1 cases were statistically significant (p <0.001). CONCLUSIONS: Local symptoms, ECOG PS, cN stage and lactate dehydrogenase were independent predictors of lymph node metastasis in patients who underwent retroperitoneal lymph node dissection. Our predictive nomogram using these factors showed excellent discrimination and calibration.

The impact of FGFR1 and FRS2α expression on sorafenib treatment in metastatic renal cell carcinoma.

BACKGROUND: Angiogenesis plays a role in tumor growth and is partly mediated by factors in both the fibroblast growth factor (FGF) and vascular endothelial growth factor (VEGF) pathways. Durable clinical responses with VEGF tyrosine kinase inhibitors (TKIs) may be limited by intrinsic tumor resistance. We hypothesized that FGF signaling may impact clinical responses to sorafenib. METHODS: Nephrectomy material was available from 40 patients with metastatic renal cell carcinoma (RCC) enrolled in a phase II clinical trial of sorafenib ± interferon (ClinicalTrials.gov Identifier NCT00126594). Fibroblast growth factor receptor 1 (FGFR1) and fibroblast growth factor receptor substrate 2 alpha (FRS2α) expression was assessed by in situ hybridization and immunofluorescence, respectively. The relationship between fibroblast growth factor pathway marker levels and progression-free survival (PFS) was analyzed using Kaplan-Meier and Cox proportional hazards regression methods. RESULTS: Univariate analysis indicated that more intense FGFR1 staining was associated with shorter PFS (log-rank P = 0.0452), but FRS2α staining was not significantly associated with PFS (log-rank P = 0.2610). Multivariate Cox proportional hazards regression models were constructed for FGFR1 and FRS2α individually, adjusting for baseline Eastern Cooperative Oncology Group performance status, treatment arm and anemia status. When adjusted for each of these variables, the highest intensity level of FGFR1 (level 3 or 4) had increased progression risk relative to the lowest intensity level of FGFR1 (level 1) (P = 0.0115). The highest intensity level of FRS2α (level 3 or 4) had increased progression risk relative to the lowest intensity level of FRS2α (level 1) (P = 0.0126). CONCLUSIONS: Increased expression of FGFR1 and FRS2α was associated with decreased PFS among patients with metastatic RCC treated with sorafenib. The results suggest that FGF pathway activation may impact intrinsic resistance to VEGF receptor inhibition.

Mucinous tubular and spindle cell carcinoma (MTSCC) of the kidney: a detailed study of radiological, pathological and clinical outcomes.

OBJECTIVE: To characterise the clinical, radiological and histological features of mucinous tubular and spindle cell carcinoma (MTSCC), as well as oncological outcomes. PATIENTS AND METHODS: This is a single institution retrospective analysis of all patients with MTSCC from 2002 to 2011. Patients were excluded if MTSCC could not be confirmed on pathology re-review (four patients). Clinical characteristics, pathology, imaging, and outcomes were reviewed for the 19 included patients. RESULTS: The median (range) age at diagnosis was 59 (17-71) years with a female predominance (78.9%). On contrast-enhanced computed tomography, MTSCC enhanced less than the cortex during the corticomedullary phase. The mean (range) tumour attenuation was 36 (24-48), 67 (41-133), 89 (49-152), and 76 (52-106) Hounsfield units in the pre-contrast, corticomedullary, nephrographic and excretory phases, respectively. In all, 16 patients were treated with partial (five patients) or radical nephrectomy (11) for pT1 (62.5%), pT2 (31.3%), and pT3a disease (6.3%). One patient underwent active surveillance. Of three patients (13.0%) managed with energy ablation, there was one recurrence that was treated with salvage surgery. One patient (5.3%) had metastatic disease at diagnosis and died from disease 64.7 months later. A patient with a pT2bN0M0 MTSCC with sarcomatoid dedifferentiation developed bone metastases 9.5 months after diagnosis and was alive at 19.0 months. The remainder were free of recurrence or progression. CONCLUSION: MTSCC is a rare renal cell carcinoma (RCC) variant. In this largest series to date, MTSCC presented at a broad range of ages and displayed a female predilection. Imaging and pathological features of MTSCC display some overlap with papillary RCC. MTSCC is associated with excellent outcomes overall, but is not universally indolent.

Partial nephrectomy in the setting of metastatic renal cell carcinoma.

PURPOSE: Cytoreductive nephrectomy remains the standard of care for appropriately selected patients with metastatic renal cell carcinoma. Although the role of partial nephrectomy is well accepted in patients with localized disease, limited data are available on partial nephrectomy in the metastatic setting. We identified the indications for and outcomes of partial nephrectomy in the setting of metastatic renal cell carcinoma with particular attention to partial nephrectomy subgroups. MATERIALS AND METHODS: We analyzed data on a consecutive cohort of 33 patients with metastatic renal cell carcinoma who underwent partial nephrectomy at a single institution between 1996 and 2011. Nonparametric statistics were used to compare partial nephrectomy subgroups. Overall survival was estimated using the Kaplan-Meier method and survival functions were compared using the log rank test. RESULTS: At presentation 8 patients had bilateral synchronous renal masses, 20 had a metachronous contralateral renal mass and 5 had a unilateral renal mass. A total of 22 patients (67%) died of disease a median of 27 months postoperatively. Patients who underwent partial nephrectomy for a metachronous contralateral renal mass and a renal mass 4 cm or less had the best overall survival (61 and 42 months, respectively). Median overall survival in patients with vs without metastatic disease at original diagnosis was 27 vs 63 months (p = 0.003). CONCLUSIONS: Our findings suggest that metastasis at the original diagnosis and the timing of presentation of the partial nephrectomy index lesion have an important role in survival. These factors should be considered when determining which patients would benefit from partial nephrectomy in the setting of metastatic renal cell carcinoma.