[Show abstract][Hide abstract] ABSTRACT: Background Papillary renal-cell carcinoma, which accounts for 15 to 20% of renal-cell carcinomas, is a heterogeneous disease that consists of various types of renal cancer, including tumors with indolent, multifocal presentation and solitary tumors with an aggressive, highly lethal phenotype. Little is known about the genetic basis of sporadic papillary renal-cell carcinoma, and no effective forms of therapy for advanced disease exist. Methods We performed comprehensive molecular characterization of 161 primary papillary renal-cell carcinomas, using whole-exome sequencing, copy-number analysis, messenger RNA and microRNA sequencing, DNA-methylation analysis, and proteomic analysis. Results Type 1 and type 2 papillary renal-cell carcinomas were shown to be different types of renal cancer characterized by specific genetic alterations, with type 2 further classified into three individual subgroups on the basis of molecular differences associated with patient survival. Type 1 tumors were associated with MET alterations, whereas type 2 tumors were characterized by CDKN2A silencing, SETD2 mutations, TFE3 fusions, and increased expression of the NRF2-antioxidant response element (ARE) pathway. A CpG island methylator phenotype (CIMP) was observed in a distinct subgroup of type 2 papillary renal-cell carcinomas that was characterized by poor survival and mutation of the gene encoding fumarate hydratase (FH). Conclusions Type 1 and type 2 papillary renal-cell carcinomas were shown to be clinically and biologically distinct. Alterations in the MET pathway were associated with type 1, and activation of the NRF2-ARE pathway was associated with type 2; CDKN2A loss and CIMP in type 2 conveyed a poor prognosis. Furthermore, type 2 papillary renal-cell carcinoma consisted of at least three subtypes based on molecular and phenotypic features. (Funded by the National Institutes of Health.).
Full-text · Article · Nov 2015 · New England Journal of Medicine
[Show abstract][Hide abstract] ABSTRACT: Urachal carcinoma is a rare tumor that has not been well studied. To determine the pathologic and clinical features of this disease, we retrospectively evaluated 46 cases from our surgical pathology files. The patients included 16 women and 30 men, with a mean age of 53.4 years (range, 28-82 years). Forty patients had undergone cystectomy, and the remaining 6 had undergone transurethral bladder biopsy. Most tumors were located at the dome (n = 44); only 2 were located at both the dome and anterior wall. All tumors consisted of adenocarcinoma, including mucinous (n = 36), enteric (n = 7), not otherwise specified (n = 2), and signet ring cell (n = 1) types. Focal areas of signet ring cell features were present in 23 cases, but urothelial carcinoma in situ was not identified in any cases. The tumors invaded the muscularis propria (n = 8), perivesical adipose tissue (n = 27), and abdominal wall (n = 3). Twenty-five patients had died of cancer at a mean of 32 months (range, 12-74 months), and 21 patients were alive at a mean of 65 months (range, 7-230 months). The median cancer-specific survival time of urachal adenocarcinoma patients was 45 months, which was significantly longer than that of bladder urothelial carcinoma patients with similar-stage disease (P = .047). Patients' cancer-specific survival was associated with tumor stage according to the Sheldon, Mayo, and TNM staging systems. In conclusion, urachal carcinomas are predominantly composed of invasive adenocarcinomas, which commonly demonstrate mucinous features. Most tumors present at advanced stages but are still associated with a better survival rate than bladder urothelial carcinomas.
[Show abstract][Hide abstract] ABSTRACT: Adenocarcinoma is an uncommon malignancy in the urinary bladder which may arise primarily in the bladder as well as secondarily from a number of other organs. Our aim is to provide updated information on primary and secondary bladder adenocarcinomas, with focus on pathologic features, differential diagnosis, and clinical relevance. Primary bladder adenocarcinoma exhibits several different growth patterns, including enteric, mucinous, signet-ring cell, not otherwise specified, and mixed patterns. Urachal adenocarcinoma demonstrates similar histologic features but it can be distinguished from bladder adenocarcinoma on careful pathologic examination. Secondary bladder adenocarcinomas may arise from the colorectum, prostate, endometrium, cervix and other sites. Immunohistochemical study is valuable in identifying the origin of secondary adenocarcinomas. Noninvasive neoplastic glandular lesions, adenocarcinoma in situ and villous adenoma, are frequently associated with bladder adenocarcinoma. It is also important to differentiate bladder adenocarcinoma from a number of nonneoplastic lesions in the bladder. Primary bladder adenocarcinoma has a poor prognosis largely because it is usually diagnosed at an advanced stage. Urachal adenocarcinoma shares similar histologic features with bladder adenocarcinoma, but it has a more favorable prognosis than bladder adenocarcinoma, partly due to the relative young age of patients with urachal adenocarcinoma.
[Show abstract][Hide abstract] ABSTRACT: 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.Modern Pathology advance online publication, 26 June 2015; doi:10.1038/modpathol.2015.68.
No preview · Article · Jun 2015 · Modern Pathology
[Show abstract][Hide abstract] ABSTRACT: We develop a functional conditional autoregressive (CAR) model for spatially correlated data for which functions are collected on areal units of a lattice. Our model performs functional response regression while accounting for spatial correlations with potentially nonseparable and nonstationary covariance structure, in both the space and functional domains. We show theoretically that our construction leads to a CAR model at each functional location, with spatial covariance parameters varying and borrowing strength across the functional domain. Using basis transformation strategies, the nonseparable spatial-functional model is computationally scalable to enormous functional datasets, generalizable to different basis functions, and can be used on functions defined on higher dimensional domains such as images. Through simulation studies, we demonstrate that accounting for the spatial correlation in our modeling leads to improved functional regression performance. Applied to a high-throughput spatially correlated copy number dataset, the model identifies genetic markers not identified by comparable methods that ignore spatial correlations.
No preview · Article · Jun 2015 · Journal of the American Statistical Association
[Show abstract][Hide abstract] ABSTRACT: Sarcomatoid transformation, wherein an epithelioid carcinomatous tumour component coexists with a sarcomatoid histology, is a predictor of poor prognosis in clear cell renal cell carcinoma (ccRCC). Our understanding of sarcomatoid change has been hindered by the lack of molecular examination. Thus, we sought to characterize molecularly the biphasic epithelioid and sarcomatoid components of sarcomatoid ccRCC and compare them to non-sarcomatoid ccRCC. We examined the transcriptome of the epithelioid and sarcomatoid components of advanced stage sarcomatoid ccRCC (n=43) and non-sarcomatoid ccRCC (n=37) from independent discovery and validation cohorts using the cDNA microarray and RNA-seq platforms. We analyzed DNA copy number profiles, generated using SNP arrays, from patients with sarcomatoid ccRCC (n=10) and advanced non-sarcomatoid ccRCC (n=155). The epithelioid and sarcomatoid components of sarcomatoid ccRCC had similar gene expression and DNA copy number signatures that were, however, distinct from those of high-grade, high-stage non-sarcomatoid ccRCC. Prognostic ccRCC gene expression profiles were shared by the biphasic components of sarcomatoid ccRCC and the sarcomatoid component showed a partial epithelial-to-mesenchymal transition signature. Our genome-scale microarray-based transcript data were validated in an independent set of sarcomatoid and non-sarcomatoid ccRCCs using RNA-seq. Sarcomatoid ccRCC is molecularly distinct from non-sarcomatoid ccRCC, with its genetic programming largely shared by its biphasic morphological components. These data explain why a low percentage of sarcomatoid histology augurs a poor prognosis; suggest the need to modify the pathological grading system; and introduce the potential for candidate biomarkers to detect sarcomatoid change preoperatively without specifically sampling the S component. This article is protected by copyright. All rights reserved.
[Show abstract][Hide abstract] ABSTRACT: Objectives:
Uroplakin (UP) II and UPIII are highly specific immunohistochemical markers for urothelial differentiation. Here we studied the sensitivity of UPII and UPIII in conventional and variant urothelial carcinomas (UCs).
Immunohistochemical staining for UPII and UPIII was performed on tissue microarray slides, including 105 conventional bladder UCs (BUCs), 90 upper urinary tract UCs (UUTUCs), and 47 micropapillary, 16 plasmacytoid, 22 small cell carcinoma, and 41 sarcomatoid UC variants.
UPII expression was significantly higher than UPIII expression in conventional BUC (44% vs 17%, P < .001) and UUTUC (67% vs 46%, P = .045). UPIII expression was significantly higher in UUTUC than in BUC (P < .001). In UC variants, UPII expression was significantly higher than UPIII expression in micropapillary (91% vs 25%, P < .001), plasmacytoid (63% vs 6%, P < .001), and sarcomatoid (29% vs 5%, P = .032) variants. Only rare cases of the small cell carcinoma variant had focal UPII and UPIII expression. Compared with conventional UC, the sarcomatoid variant had significantly lower UPII expression, whereas the micropapillary variant had significantly higher UPII expression (P < .001).
UPII demonstrates a significantly higher sensitivity than UPIII in conventional and variant UCs. Thus, UPII is a more valuable marker than UPIII in immunohistochemical analyses for confirming the urothelial origin of carcinomas.
No preview · Article · Dec 2014 · American Journal of Clinical Pathology
[Show abstract][Hide abstract] ABSTRACT: Purpose:
While many urologists recommend radical cystectomy for micropapillary bladder cancer invading the lamina propria (cT1), contradictory small reports exist on the efficacy of conservative management with intravesical bacillus Calmette-Guérin for this disease. We report our updated experience in what to our knowledge is the largest series of patients with cT1 micropapillary bladder cancer.
Materials and methods:
An institutional review board approved review of our cancer database identified 283 patients with micropapillary bladder cancer, including 72 staged with cT1N0M0 disease at diagnosis and initiation of therapy. Survival analysis was performed using the Kaplan-Meier estimator and compared using the log rank test.
In this cohort of 72 patients 40 received primary intravesical bacillus Calmette-Guérin and 26 underwent up-front radical cystectomy. Of patients who received bacillus Calmette-Guérin 75%, 45% and 35% experienced disease recurrence, progression and lymph node metastasis, respectively. Patients treated with up-front cystectomy had improved survival compared to patients treated with primary bacillus Calmette-Guérin (5-year disease specific survival 100% vs 60% p = 0.006) and patients who underwent delayed cystectomy after recurrence (5-year disease specific survival 62%, p = 0.015). Prognosis was especially poor in patients who waited for progression before undergoing radical cystectomy with an estimated 5-year disease specific survival of only 24% and a median survival of 35 months. In patients treated with up-front cystectomy pathological up-staging was found in 27%, including 20% with lymph node metastasis.
While certain patients with T1 micropapillary bladder cancer may respond to intravesical bacillus Calmette-Guérin, survival is improved in those who undergo early radical cystectomy. Further molecular studies are needed to identify subsets of patients in whom the bladder can be safely spared.
Full-text · Article · Sep 2014 · The Journal of Urology