Renal Neoplasia in Tuberous Sclerosis: A Study of 41 Patients

ObjectiveTo study the clinical features and identify unique renal neoplasia subtypes and their prognostic implications in individuals with tuberous sclerosis complex (TSC).Patients and MethodsThe Mayo Clinic nephrectomy registry included 37 patients with TSC diagnosed between 1970 and 2018. Four additional patients were identified from the pathology consultation and autopsy files. All available renal tumors were further characterized using immunohistochemistry and fluorescence in situ hybridization. Clinicopathologic features and follow-up were obtained from the medical record. The American Association for Cancer Research Project GENIE registry was accessed using cBioPortal for molecular profiling of angiomyolipoma (AML).ResultsA total of 276 renal tumors from 41 patients were analyzed. Renal tumors were classified into 9 distinct morphological subtypes, with AML predominating (238 [86%]). Interestingly, all these tumors acted in a benign fashion except one renal cell carcinoma with clear cells and fibromyomatous stroma and one epithelioid AML that metastasized. Molecular profiling studies revealed that epithelioid AMLs were enriched for alterations of TP53, RB1, and ATRX. Eight patients died of direct complications of TSC, including 3 of end-stage renal disease. To date, none have died of a renal epithelial neoplasm.ConclusionThe identification of unique renal neoplasia subtypes may provide important clues to establish a diagnosis of TSC, and in the somatic setting, this finding has important implications for accurate prognostication. These tumors tend to be indolent, and only 2 of 276 tumors in our study exhibited metastatic behavior. Our results support multidisciplinary management with a focus on preservation of renal function.     

Molecular testing for melanocytic tumors: a practical update

The work-up of melanocytic tumors has undergone significant changes in the last years following the exponential growth of molecular assays. For the practicing pathologist it is often difficult to sort through the myriad of different tests available currently for clinical use. The molecular tests used in melanocytic pathology can be broadly divided into 4 categories: (i) Tests useful in the differential diagnosis of nevus versus melanoma (primarily used as an aid in the diagnosis of histologically ambiguous melanocytic tumors), (ii) Tests that predict prognosis in melanoma, (iii) Tests useful in the classification of melanocytic tumors and (iv) Tests that predict response to systemic therapy in melanoma. This review will present an updated overview of major ancillary tests used in clinical practice.     

Pathology of valved venous homografts used as right ventricle-to-pulmonary artery conduits in congenital heart disease surgery

Objectives

Although valved venous homografts (VVHs) are used for establishing right ventricle-to-pulmonary artery continuity in some complex heart defects, the tissue changes that occur in situ have not been described. We review the gross and microscopic changes observed in explanted VVH conduits and their effects on functionality.

Next-generation Sequencing for ALK and ROS1 Rearrangement Detection in Patients With Non–small-cell Lung Cancer: Implications of FISH-positive Patterns

BackgroundDetection of ALK and ROS1 gene rearrangements in non–small-cell lung cancer is required for directing patient care. Although fluorescence in situ hybridization (FISH) and immunohistochemistry have been established as gold standard methods, next-generation sequencing (NGS) platforms are called to be at least equally successful. Comparison of these methods for translation into daily use is currently under investigation.Patients and MethodsForty non–small-cell lung cancer paraffin-embedded samples with previous ALK (n = 33) and ROS1 (n = 7) FISH results were examined with the Oncomine Focus Assay and tested for ALK and ROS1 immunoreactivity. Clinical implications of concurrent molecular alterations and concordance between methods were evaluated.ResultsNGS was successful in 32 (80%) cases: 25 ALK and 7 ROS1. Few concomitant alterations were detected: 1 ALK rearranged case had an ALK p.L1196M-resistant mutation, 4 had CDK4, MYC, and/or ALK amplifications, and 1 ROS1 rearranged case showed a FGFR4 amplification. Comparison between techniques revealed 5 (16%) discordant cases that had lower progression-free survival than concordant cases: 7.6 (95% confidence interval, 2.2-13) versus 19.4 (95% confidence interval, 10.1-28.6). Remarkably, 4 of these cases had isolated 3' signal FISH pattern (P = .026).ConclusionOur data support that the identification of 3' isolated signal FISH pattern in ALK and ROS1 cases might suggest a false-positive result. NGS seems a reliable technique to assess ALK and ROS1 rearrangements, offering the advantage over immunohistochemistry of detecting other molecular alterations with potential therapeutic implications.     

Intratumoral heterogeneity of esophageal squamous cell carcinoma and its clinical significance

Recent studies have shown that intratumoral heterogeneity is prevalent in esophageal squamous cell cancer (ESCC) based on DNA sequencing and chromosome analysis in multiple regions from the same tumor. This study aimed to investigate the expression of ZNF750, EP300, MTOR and KMT2D and their intratumoral heterogeneity (ITH) in patients with ESCC. A total of 106 cases, who underwent esophagectomy from 2008 to 2010, with two foci from each case, were tested by immunohistochemistry(IHC) as well as 12 cases were tested by RNAscope in this study.We found that 58/106 (54.72%), 66/106 (62.26%), 75/106 (70.75%%) of ESCC showed high expression of ZNF750, EP300, MTOR, respectively by IHC, and 8/12 (66.67%), 10/12 (83.33%), 4/12 (33.33%) and 6/12 (50%) showed high expression of ZNF750, EP300, MTOR and KMT2D, respectively by RNAscope. Multivariate analysis showed that MTOR expression was an independent infavorable prognostic factor of overall survival (OS) (HR?=?1.921; P?=?0.000). This study also found that 44/106(4151%), 37/106 (34.91%), 39/106(36.79%) of ESCC showed heterogeneous expression of ZNF750, EP300 and MTOR respectively by IHC, 8/12(66.67%), 8/12(66.67%), 4/12(33.33%), 4/12(33.33%) of ZNF750, EP300, MTOR and KMT2D respectively by RNAscope, IHC and RNAscope could successfully detect a high prevalence of ITH. In conclusion, findings of this study showed that ZNF750, EP300, MTOR and KMT2D heterogeneously expressed in ESCC. High expression of ZNF750 related to a better outcome, while EP300 and MTOR related to a poor prognosis.     

Rapid in-situ hybridization and immunohistochemistry: a pilot comparative study of two rapid diagnostic techniques for establishing monoclonality in plasma cell dyscrasias

BackgroundLight chain restriction needs to be established on the paraffin embedded tissue in certain types of plasma cell dyscrasias when serum levels of monoclonal immunoglobulins and light chain assays in the urine and serum may be normal. Rapid-in-situ-hybridisation (RISH) is thought to be a superior to immunohistochemistry (IHC) for kappa and lambda staining due to brighter and crisp staining without any background.MethodsFifty cases were included in this pilot study. Serum light chain restriction status of the case was taken as gold standard. The results of standard IHC for kappa and lambda immunoglobulins on the bone marrow biopsy of these cases was compared with RISH performed by the two commercially available kits. The results of the two methods were compared for sensitivity, need to repeat the test and background staining.ResultsThe study found that in IHC first run sensitivity was 58% which improved to 88% after the second run. For RISH the sensitivity was 100%.ConclusionRapid-in-situ-hybridisation (RISH) is a superior technique to IHC for detecting kappa and lambda light chain in plasma cells. The test is as labour intensive and time consuming as the routine IHC but has no background staining with more bright and crisp staining quality.     

一例外周血染色体核型为单纯型18三体但智力正常女性的遗传学研究

目的分析1例外周血染色体核型为单纯型18三体但智力正常女性的遗传学机制。方法用G显带染色体核型分析、荧光原位杂交(fluorescence in situ hybridization,FISH)和单核苷酸多态性微阵列芯片(single nucleotide polymorphism microarray,SNP-array)技术对患者的外周血和颊粘膜细胞进行检测。结果患者的外周血染色体核型、SNP-array以及FISH检测结果均提示为47,XX,+18;颊粘膜间期细胞FISH检测结果提示为45,X合并低比例的18三体和18单体。结论胚层染色体嵌合的个体临床表现复杂,遗传学异常所造成的影响取决于相关胚层分化所形成的器官及功能。     

非肌性肌球蛋白II-C在斑马鱼胚胎发育过程中的表达*

目的：分析NM II-C在斑马鱼胚胎发育过程中表达的时空变化。方法：收集不同发育阶段的斑马鱼胚胎，应用整体原位杂交技术研究NM II-C在斑马鱼胚胎发育过程中的表达变化情况。结果：受精后17和22小时，NM II-C由原先的广泛表达渐渐集中于前脑、中脑和后脑；受精后26和36小时，NM II-C表达分布到整个中枢神经系统；受精后48小时，NM II-C表达在脊髓变得很弱，主要集中于大脑。结论：揭示了NM II-C基因在斑马鱼胚胎发育过程中的时间和空间上的表达进程，为进一步探讨其在发育中的调控作用提供了实验基础。     

Evaluation of environmental genotoxicity by comet assay in Columba livia

The concentrations of recognized or suspected genotoxic and carcinogenic agents found in the air of large cities and, in particular, developing countries, have raised concerns about the potential for chronic health effects in the populations exposed to them. The biomonitoring of environmental genotoxicity requires the selection of representative organisms as “sentinels,” as well as the development of suitable and sensitive assays, such as those aimed at assessing DNA damage. The aim of this study was to evaluate DNA damage levels in erythrocytes from Columba livia living in the metropolitan area of Monterrey, Mexico, compared with control animals via comet assay, and to confirm the results via Micronuclei test (MN) and DNA breakage detection–fluorescence in situ hybridization (DBD–FISH). Our results showed a significant increase in DNA migration in animals from the area assayed compared with that observed in control animals sampled in non-contaminated areas. These results were confirmed by MN test and DBD–FISH. In conclusion, these observations confirm that the examination of erythrocytes from Columba livia via alkaline comet assay provides a sensitive and reliable end point for the detection of environmental genotoxicants.