Evaluating the Effects of Kidney Preservation at 10 °C with Hemopure and Sodium Thiosulfate in a Rat Model of Syngeneic Orthotopic Kidney Transplantation.

Kidney transplantation is preferred for end-stage renal disease. The current gold standard for kidney preservation is static cold storage (SCS) at 4 °C. However, SCS contributes to renal graft damage through ischemia-reperfusion injury (IRI). We previously reported renal graft protection after SCS with a hydrogen sulfide donor, sodium thiosulfate (STS), at 4 °C. Therefore, this study aims to investigate whether SCS at 10 °C with STS and Hemopure (blood substitute), will provide similar protection. Using in vitro model of IRI, we subjected rat renal proximal tubular epithelial cells to hypoxia-reoxygenation for 24 h at 10 °C with or without STS and measured cell viability. In vivo, we preserved 36 donor kidneys of Lewis rats for 24 h in a preservation solution at 10 °C supplemented with STS, Hemopure, or both followed by transplantation. Tissue damage and recipient graft function parameters, including serum creatinine, blood urea nitrogen, urine osmolality, and glomerular filtration rate (GFR), were evaluated. STS-treated proximal tubular epithelial cells exhibited enhanced viability at 10 °C compared with untreated control cells (p < 0.05). Also, STS and Hemopure improved renal graft function compared with control grafts (p < 0.05) in the early time period after the transplant, but long-term function did not reach significance. Overall, renal graft preservation at 10 °C with STS and Hemopure supplementation has the potential to enhance graft function and reduce kidney damage, suggesting a novel approach to reducing IRI and post-transplant complications.

Microscopic Kidney Disease in Tuberous Sclerosis Complex and Treatment With mTOR Inhibition.

Declining kidney function in tuberous sclerosis complex (TSC) is often attributed to large lesions, including angiomyolipomas (AMLs) and cysts, that encroach on the normal parenchyma or that require intervention and loss of parenchyma from surgical debulking or embolization. Consequently, research on inhibitors of the mammalian target of rapamycin (mTOR), a protein complex implicated in TSC pathophysiology for its role in promoting cell growth and proliferation, has largely focused on their ability to reduce AML size. Clinical guidelines distilled from this research limit mTOR inhibition as a first-line treatment to patients with large AMLs. However, chronic kidney disease (CKD) occurs in patients without large AMLs or a history of renal intervention. Alternate mechanisms postulated for CKD in TSC may suggest a role for mTOR inhibition in this population. In this report, we present 2 cases of a microscopic variant of TSC kidney disease causing declining kidney function, as well as anecdotal evidence for the use of mTOR inhibition to improve kidney function in the absence of large AMLs. We highlight the importance of annual kidney function assessment in patients with TSC and suggest a low threshold for kidney biopsy in patients with declining glomerular filtration rate without a clear etiology clinically or radiographically.

Clinical Significance of Isolated V1 Arteritis in Renal Transplantation.

BACKGROUND: The presence of intimal arteritis (v) in renal allograft biopsy specimens establishes the presence of acute T-cell mediated rejection (TCMR), Grade IIa-III, according to the Banff classification of rejection. The clinical significance of isolated v1 lesions (v1), characterized by arteritis alone, compared with lesions of arteritis with tubulointerstitial inflammation (i-t-v) has been controversial. METHODS: We performed a retrospective review of 280 patients undergoing renal transplantation between 2005 and 2015 who received a "for cause" transplant biopsy using the Banff 2013 classification. Patients with TCMR grade IIa (n = 83) were subdivided into groups with isolated v1 arteritis and i-t-v. Pre- and postoperative renal function, graft survival, and overall survival were evaluated in all patients. RESULTS: Donor and recipient demographics were similar between groups. One month following treatment of rejection, patients with v1 disease had superior recovery of glomerular filtration rate vs patients with i-t-v (P < .002). At a median follow-up of 41 months from transplant, death-censored graft survival was 92% vs 79% (P = .04), and overall survival was 98% vs 79% (P < .004) in the isolated v1 and i-t-v groups, respectively. CONCLUSION: Despite having identical Banff classification of TCMR IIa, our results indicate that graft survival in patients with isolated v1 rejection is superior to those with i-t-v. Following corroboration with data from other centers, modification of the Banff classification scheme should be considered.

Pilomatrixoma with Atypical Features: A Case Report.

Pilomatrixoma is an uncommon, benign tumor with differentiation towards both the hair matrix and cells arising in the cortex, most frequently appearing in the first or second decade of life. In rare instances, pilomatrixomas can show malignant transformation. Pilomatrix carcinoma is extremely uncommon and has traditionally been considered a tumor of low malignant potential; however, a high local recurrence rate has been reported. There is a paucity of literature on these lesions, with only a few reports describing the spectrum of malignant changes seen in these lesions. In this case report, we present a case of pilomatrixoma in an adult patient showing atypical features. While the tumor is small, there are focal features that suggest progression to malignancy, but do not fulfill the criteria for pilomatrix carcinoma. These focal atypical features include a focal infiltrative pattern at the periphery, with a variable cytological atypia and an increased mitotic rate, up to five mitotic events/high-power field. Irregular foci of central necrosis (comedonecrosis) were present in several lobules. Some of the features identified were similar to a subset of pilomatrixoma, known as "proliferating pilomatrixoma." However, our case did not have the diffuse changes or larger size that has been frequently reported in "proliferating pilomatrixoma." In conclusion, given the lack of focality of the changes, the lesion in our case is best described as a pilomatricoma with atypical features. Furthermore, our case may highlight the need to ensure close clinical follow-up for these lesions with unexpected atypical features that raise concern of recurrence and malignant transformation.

Patterns of Expression of H2S-Producing Enzyme in Human Renal Cell Carcinoma Specimens: Potential Avenue for Future Therapeutics.

BACKGROUND: Renal cell carcinoma (RCC) is the most common cancer of the kidney. The most common histotype is clear-cell (cc) RCC. Hydrogen sulfide (H2S) is an angiogenic and anti-apoptotic gasotransmitter that is elevated under pseudohypoxic conditions. H2S is endogenously produced by three enzymes: Cystathionine γ-lyase (CSE), cystathionine ß-synthase (CBS), and 3-mercaptopyruvate sulfurtransferase (MPST). Seeing as increased expression of these enzymes has been observed in other human cancer types, this study aimed to quantify H2S-producing enzyme expression in human RCC samples and evaluate whether it correlated with clinical outcomes. PATIENTS AND METHODS: Eighty-eight human kidney tissue specimens, with healthy and cancerous tissue components, were immunohistochemically stained for CSE, CBS, and MPST. The mean pixel intensity of positively stained areas was quantified. A retrospective analysis was conducted to obtain patient demographics, rates of metastasis/recurrence, and prognostic characteristics. Statistical correlations between enzyme expressions and subsequent patient outcomes were evaluated. RESULTS: There was significantly greater expression of CSE, CBS, and MPST in cc-RCC compared to paired healthy tissue (p<0.0001). The difference in expression of CSE in cancerous versus normal tissue was significantly greater than that for CBS and MPST (p<0.0001 and p<0.01, respectively). Enzyme expression patterns in cancerous versus normal tissue did not correlate with nuclear grade, stage, histological type or cancer recurrence/metastasis. CONCLUSION: To our knowledge, this is the first report of the differential increase in expression of CSE, CBS, and MPST in human RCC. Although these patterns do not appear to correlate with cancer recurrence, metastasis, size or nuclear grade, their differential increase suggests a potential therapeutic target.

Expression of immune checkpoints in active nonsegmental vitiligo: a pilot study.

BACKGROUND: Vitiligo is a depigmentary skin disfigurement resulting from destruction of melanocytes caused by a possible malfunctioning immunity. This destruction could be linked to an aberrant T-cell-mediated immune response. Cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) and programmed death-1 (PD-1) are immune checkpoints capable of downregulating T-cell immune functions. OBJECTIVES: To evaluate the pattern of expression of PD-1 and CTLA-4 in active vitiligo skin. METHODS: Thirty nonsegmental vitiligo (NSV) patients had been included in this pilot study. Marginal, lesional, and nonlesional skin biopsies were obtained. PD-1 and CTLA-4 immunohistochemistry expression in the mononuclear inflammatory infiltrates were evaluated using digital images. RESULTS: The marginal and lesional inflammatory infiltrates were significantly abundant when compared to nonlesional ones. The marginal infiltrates were significantly abundant when compared to the lesional ones. PD-1 and CTLA-4 were significantly expressed in the marginal and lesional infiltrates when compared to nonlesional skin. Moreover, the marginal expression of PD-1 was significantly higher than the lesional expression. However, no similar significant difference in CTLA-4 expression was found between the marginal and lesional infiltrates. Significant positive correlations were found between the expressions of PD-1 and CTLA-4 in marginal and lesional infiltrates. CONCLUSION: Programmed death-1 and CTLA-4 are expressed within the inflammatory infiltrate of active NSV. Further studies are required to confirm their significance in the development or limitation of the disease.

Renal Lymphangiectasia in the Transplanted Kidney: Case Series and Literature Review.

BACKGROUND: Renal lymphangiectasia is a rare and poorly understood lymphatic disease associated with lymphatic dilation and leakage. To our knowledge, no cases have been described in the context of a transplanted kidney. METHODS: We describe 2 cases of renal lymphangiectasia in transplanted kidneys, both from pediatric donors. RESULTS: The cases of allograft lymphangiectasia are characterized by severe, symptomatic ascites refractory to attempts at medical and surgical management, and ultimately requiring allograft nephrectomy. CONCLUSIONS: While lymphatic complications, particularly lymphoceles, are not uncommon in renal transplantation, lymphangiectasia is a distinct condition which should be considered in renal transplant patients with ascites, after all other sources have been ruled out.

Malignant cylindroma of the scalp treated with staged perimeter excision: A case report and literature review.

Malignant cylindroma is a rare and poorly understood cutaneous malignancy. There is a paucity of literature on these lesions, with only a select number of case reports and limited guidelines on management. We present a case of a 60-year old patient with a malignant cylindroma of the scalp treated surgically with staged perimeter excision and summarize our review of the literature with a focus on management of this potentially aggressive disease.

A miRNA-based classification of renal cell carcinoma subtypes by PCR and in situ hybridization.

Renal cell carcinoma (RCC) constitutes an array of morphologically and genetically distinct tumors the most prevalent of which are clear cell, papillary, and chromophobe RCC. Accurate distinction between the typically benign-behaving renal oncocytoma and RCC subtypes is a frequent challenge for pathologists. This is critical for clinical decision making. Subtypes also have different survival outcomes and responses to therapy. We extracted RNA from ninety formalin-fixed paraffin-embedded (FFPE) tissues (27 clear cell, 29 papillary, 19 chromophobe, 4 unclassified RCC and 11 oncocytomas). We quantified the expression of six miRNAs (miR-221, miR-222, miR-126, miR-182, miR-200b and miR-200c) by qRT-PCR, and by in situ hybridization in an independent set of tumors. We developed a two-step classifier. In the first step, it uses expression of either miR-221 or miR-222 to distinguish the clear cell and papillary subtypes from chromophobe RCC and oncocytoma (miR-221 AUC: 0.96, 95% CI: 0.9132-1.014, p < 0.0001 and miR-222 AUC: 0.91, 95% CI: 0.8478-0.9772, p < 0.0001). In the second step, it uses miR-126 to discriminate clear cell from papillary RCC (AUC: 1, p < 0.0001) and miR-200b to discriminate chromophobe RCC from oncocytoma (AUC: 0.95, 95% CI: 0.8933-1.021, p < 0.0001). In situ hybridization showed a nuclear staining pattern. miR-126, miR-222 and miR-200b were significantly differentially expressed between the subtypes by in situ hybridization. miRNA expression could distinguish RCC subtypes and oncocytoma. miRNA expression assessed by either PCR or in situ hybridization can be a clinically useful diagnostic tool to complement morphologic renal tumor classification, improving diagnosis and patient management.

An update on the molecular pathology of urinary bladder tumors.

Urothelial carcinoma is the fourth most common tumors after prostate cancer, lung, and colorectal carcinoma but the second most common urologic malignancy. Urothelial carcinoma composed more than 90% of bladder tumors while squamous cell carcinoma and adenocarcinomas composed 5% and 2% respectively. The intense research involving the different molecular aspects of bladder cancer has provided a great insight into identifying more about molecular profiling and pathways of bladder cancer. In this review, we will highlight the general concepts of the molecular features; profiling and classification as well as the molecular pathways for bladder carcinomas, especially urothelial carcinoma. Also, we will discuss the advances of molecular biomarkers for screening, early diagnosis, surveillance and potential prognosis of urothelial carcinoma of the bladder. Studies showed that accumulation of genetic alterations involving the clonal expansion of altered cells with growth advantages through sequential multi-step pathways results in progression of bladder tumors. The accumulated research data from literature has revealed that the genomic signatures of urothelial carcinoma are required to subclassify bladder cancer into genetically distinct subgroups. These findings could improve the understating of pathogenesis as well as will provide new therapeutic modules e.g. targeted therapy.

Incidental Prostate Adenocarcinoma in Cystoprostatectomy Specimens: Partial Versus Complete Prostate Sampling.

BACKGROUND: The rate of incidental prostate adenocarcinoma (PCa) detection in radical cystoprostatectomy (RCP) varies widely, ranging from 15% to 54%. Such variability may be explained by institutional differences in prostate grossing protocols. Either partial or complete submission of the prostate gland in RCP may result in detection of clinically insignificant or significant incidental PCa. The aim of the study was to compare the clinical significance of PCa in RCP specimens in partial versus complete sampling. MATERIAL: Seventy-two out of 158 RCP cases showed incidental PCa. The pathologic features, including Gleason score, margin status, extraprostatic extension (EPE), seminal vesicle invasion (SVI), PCa stage, and tumor volume, were assessed. RESULTS: The 72 cases were divided into partial (n = 21, 29.1%) and complete sampling (n = 51, 70.8%) groups. EPE was detected in 13/72 (18.1%) with 11/13 (84.6%) cases in the complete group. Positive margins were present in 11/72 (15.3%) with 9/11 (81.8%) in the complete group. SVI was detected in 4/72 (5.6%) with 3/4 (75.0%) in the complete group. Overall, 4/72 (5.6%) had a Gleason score >7, all of which were in the complete group. CONCLUSION: Our data suggest that complete sampling of the prostate may be the ideal approach to grossing RCP specimens, allowing for greater detection of clinically significant incidental PCa.

Acute urinary retention secondary to urethral involvement of granulomatosis with polyangiitis.

Granulomatosis with polyangiitis (GPA, formerly Wegener's granulomatosis) is a systemic necrotizing vasculitis of small- and medium-sized blood vessels, primarily affecting the upper and lower respiratory tracts, as well as the kidneys. Urogenital manifestations of GPA are exceedingly rare and usually respond well to systemic immunosuppressive therapy. Here, we present a case of a 36-year-old female presenting with acute urinary obstruction secondary to urethral GPA involvement in the immediate postpartum period. Special consideration should be given to ruling out malignancy in all patients with a history of GPA and urethral lesions, especially when there is a history of cyclophosphamide treatment.

Performance of residents using digital images versus glass slides on certification examination in anatomical pathology: a mixed methods pilot study.

BACKGROUND: It is anticipated that many licensing examination centres for pathology will begin fully digitizing the certification examinations. The objective of our study was to test the feasibility of a fully digital examination and to assess the needs, concerns and expectations of pathology residents in moving from a glass slide-based examination to a fully digital examination. METHODS: We conducted a mixed methods study that compared, after randomization, the performance of senior residents (postgraduate years 4 and 5) in 7 accredited anatomical pathology training programs across Canada on a pathology examination using either glass slides or digital whole-slide scanned images of the slides. The pilot examination was followed by a post-test survey. In addition, pathology residents from all levels of training were invited to participate in an online survey. RESULTS: A total of 100 residents participated in the pilot examination; 49 were given glass slides instead of digital images. We found no significant difference in examination results between the 2 groups of residents (estimated marginal mean 8.23/12, 95% confidence interval [CI] 7.72-8.87, for glass slides; 7.84/12, 95% CI 7.28-8.41, for digital slides). In the post-test survey, most of the respondents expressed concerns with the digital examination, including slowly functioning software, blurring and poor detail of images, particularly nuclear features. All of the respondents of the general survey (n = 179) agreed that additional training was required if the examination were to become fully digital. INTERPRETATION: Although the performance of residents completing pathology examinations with glass slides was comparable to that of residents using digital images, our study showed that residents were not comfortable with the digital technology, especially given their current level of exposure to it. Additional training may be needed before implementing a fully digital examination, with consideration for a gradual transition.

MicroRNA-194 is a Marker for Good Prognosis in Clear Cell Renal Cell Carcinoma.

Clear cell renal cell carcinoma (ccRCC) is the most prevalent adult kidney cancer. Prognostic markers are needed to guide patient management toward aggressive versus more conservative approaches, especially for small tumors ≤4 cm. miR-194 was reported to be downregulated in several cancers and is involved in epithelial to mesenchymal transition. We evaluated miR-194 as a prognostic marker in ccRCC. In a cohort of 234 patients with primary ccRCC, we correlated miR-194 expression level with multiple clinicopathological features including disease-free and overall survival, tumor size, clinical stage, and histological grade. Our results shows a stepwise decrease in miR-194 expression from normal kidney to primary ccRCC (P = 0.0032) and a subsequent decrease from primary to metastatic lesions. Additionally, patients with higher miR-194 expression has significantly longer disease-free survival (P = 0.041) and overall survival (P = 0.031) compared to those with lower expression. In multivariate analysis, miR-194-positive tumors retain significance in disease-free survival and overall survival, suggesting miR-194 is an independent marker for good prognosis in ccRCC. Moreover, miR-194 is a marker for good prognosis for patients with small renal masses (P = 0.014). These findings were validated on an independent data set from The Cancer Genome Atlas. We also compared miR-194 expression between RCC subtypes. ccRCC had the highest levels, whereas chromophobe RCC and oncocytoma had comparable lower levels. Target prediction coupled with pathway analysis show that miR-194 is predicted to target key molecules and pathways involved in RCC progression. miR-194 represents a prognostic biomarker in ccRCC.

S100A11 is a potential prognostic marker for clear cell renal cell carcinoma.

Clear cell renal cell carcinoma (ccRCC) is one of few cancers with rising incidence in North America. The prognosis of ccRCC is variable and difficult to predict. Stratification of patients according to disease aggressiveness can significantly improve patient management. We investigated the expression of the S100A11 protein in 385 patients with primary ccRCC using immunohistochemistry on tissue microarrays. We compared its expression with clinicopathologic parameters and patients' survival. We also validated our results at the mRNA level on an independent set from The Cancer Genome Atlas. As a dichotomous variable (low vs. high expression), there was a significant association between S100A11 expression and tumor grade, with higher expression associated with higher tumor grades (p < 0.001). High expression was also significantly more frequently seen in higher versus lower stages (56 vs. 28 %). In the univariate analysis, high S100A11 expression was associated with significantly shorter disease-free survival (DFS) (HR = 2.28; p = 0.001). This was maintained in the multivariate analysis (HR = 1.69; p = 0.042). Expression was not associated with overall survival (OS) (p = 0.10). Comparable results were obtained when S100A11 expression was analyzed as a trichotomous variable (low, moderate, or high expression). The Kaplan­Meier survival analyses showed that higher S100A11 expression was associated with statistically significant decrease in DFS (p < 0.001), but not OS (p = 0.1).

Alpha-enolase is a potential prognostic marker in clear cell renal cell carcinoma.

Clear cell renal cell carcinoma (ccRCC) is an aggressive disease with unpredictable behaviour. Clinical parameters are not always accurate for prognosis prediction. The integration of molecular markers to prognostic models can significantly improve prognostic assessment and consequently patient management. We assessed the expression of alpha-enolase (ENO1) protein by immunohistochemistry in 360 patients with primary ccRCC and correlated its expression with multiple clinicopathological parameters including stage, grade, tumor size, disease-free and overall survival. Cox proportional hazard regression models adjusted for clinicopathological factors were used to test for a link between ENO1 expression and both disease-free and overall survival. We correlated ENO1 mRNA expression with overall survival in an independent set of 428 ccRCC cases from The Cancer Genome Atlas. ENO1 showed cytoplasmic, membranous and nuclear staining patterns. There is a statistically significant negative correlation between ENO1 expression, tumor stage, and grade. ENO1 expression also shows a statistically significant direct correlation with disease-free survival (p = 0.011) and overall survival (p = 0.030) in ccRCC. Patients with higher ENO1 expression had lower hazard ratio of recurrence, although this was not statistically significant (HR = 0.330, p = 0.060). These findings were validated at the mRNA level in an independent set of 428 ccRCC cases which also showed that low ENO1 expression is associated with significantly shorter overall survival. Down-regulation of ENO1 can be a predictor of poor prognosis in ccRCC, and it can be a potential prognostic marker.

Profilin-1 expression is associated with high grade and stage and decreased disease-free survival in renal cell carcinoma.

Clear cell renal cell carcinoma (ccRCC) is associated with high mortality, although individual outcomes are highly variable. Identification of patients with increased risk of disease progression can guide customizing management plan according to disease severity. Profilin-1 (Pfn1) has been recently identified as overexpressed in metastatic ccRCC compared with primary tumors. We examined Pfn1 expression in a tissue microarray of 384 cases of histologically confirmed primary ccRCC with detailed clinical follow-up. Profilin-1 expression showed both cytoplasmic and nuclear staining patterns. The immunoexpression of Pfn1 was scored in a semiquantitative fashion. There was no significant difference in Pfn1 expression between normal kidney and kidney ccRCC. Our results show that strong cytoplasmic Pfn1 expression is associated with high-grade (P < .001) and high-stage (III-IV) (P = .018) disease. Univariate analysis of the data set showed that higher Pfn1 expression is associated with significantly shorter disease-free survival (hazard ratio 7.36, P = .047) and also lower overall survival. Kaplan-Meier analysis showed that high cytoplasmic expression of Pfn1 was also associated with a statistically significant lower disease-free survival (P = .018). It was also associated with lower overall survival, although this was not statistically significant. Profilin-1 lost its prognostic significance in the multivariate analysis when controlling for grade and stage. Profilin-1 expression was not associated with significant prognostic deference in the subgroup of patients with stage 1 disease. Our results suggest that the evaluation of Pfn1 by immunohistochemistry may help to identify patients with an increased risk of disease progression. We validated our results at the messenger RNA level on an independent patient cohort. Higher messenger RNA expression of Pfn1 is associated with significantly lower survival.

Incidental Merkel cell carcinoma in a cutaneous horn: a case report.

Merkel cell carcinoma (MCC) is a rare cutaneous neuroendocrine malignancy, which usually presents as an asymptomatic, rapidly growing, firm nodule on sun-damaged skin. We present a 93-year-old female who presented with a "cutaneous horn" on the face. On excision, histologic examination revealed a combined squamous cell carcinoma in situ with underlying MCC. Merkel cell polyomavirus immunohistochemistry was negative in this lesion. This case report highlights the significant association between MCC and squamous cell carcinoma and the uncommon clinical presentation of this combined tumor in the form of a cutaneous horn.

miR-210 is a prognostic marker in clear cell renal cell carcinoma.

Accurate assessment of prognosis of clear cell renal cell carcinoma (ccRCC) is key in optimizing management plans to fit individual patient needs. miRNAs are short noncoding single-stranded RNAs that control the expression of target genes and may act as cancer biomarkers. We analyzed the expression of miR-210 in 276 cases of primary ccRCC and compared its expression in 40 pairs of adjacent normal and cancerous tissues. We assessed its expression in primary and metastatic tumors, in the common RCC subtypes, and the benign oncocytoma. The results were validated with an independent data set from The Cancer Genome Atlas. miR-210 was significantly overexpressed in ccRCC compared with normal kidney. miR-210(+) patients had a statistically higher chance of disease recurrence [hazard ratio (HR), 1.82; P = 0.018] and shorter overall survival (HR, 2.46; P = 0.014). In multivariate analysis, miR-210 lost its statistically significant association with shorter disease-free survival and overall survival after adjusting for tumor size and tumor, node, metastasis stage. Papillary RCC showed comparable miR-210 overexpression, whereas decreased up-regulation was seen in chromophobe RCC and oncocytoma. A number of predicted targets that might be involved in carcinogenesis and aggressive tumor behavior were identified. miR-210 is a potential therapeutic target and independent marker of poor prognosis of ccRCC.