Histiocytic sarcoma is a rare malignant neoplasm that may occur
or in the context of a previous hematologic malignancy or mediastinal germ cell tumor. Here, we performed whole exome sequencing and ...RNA-sequencing (RNA-Seq) on 21 archival cases of primary histiocytic sarcoma. We identified a high number of genetic alterations within the RAS/RAF/MAPK pathway in 21 of 21 cases, with alterations in
(6 of 21),
(5 of 21),
(4 of 21),
(4 of 21),
(4 of 21),
(1 of 21), and
(1 of 21), including single cases with homozygous deletion of
, high-level amplification of
, and a novel
fusion. Concurrent
and
mutations were present in 3 of 21 cases, and 5 of 7 cases with alterations in
and/or
had disease involving the gastrointestinal tract. Following unsupervised clustering of gene expression data, cases with
and/or
abnormalities formed a distinct tumor subgroup. A subset of
wild-type cases had frequent mutations in B-cell lymphoma associated genes and/or clonal IG gene rearrangements. Our findings expand the current understanding of the molecular pathogenesis of this rare tumor and suggest the existence of a distinct subtype of primary histiocytic sarcoma characterized by
alterations with predilection for the gastrointestinal tract.
Recently, the BRAF V600E mutation was reported in all cases of hairy cell leukemia (HCL) but not in other peripheral B-cell neoplasms. We wished to confirm these results and assess BRAF status in ...well-characterized cases of HCL associated with poor prognosis, including the immunophenotypically defined HCL variant (HCLv) and HCL expressing the IGHV4-34 immunoglobulin rearrangement. Fifty-three classic HCL (HCLc) and 16 HCLv cases were analyzed for BRAF, including 5 HCLc and 8 HCLv expressing IGHV4-34. BRAF was mutated in 42 (79%) HCLc, but wild-type in 11 (21%) HCLc and 16 (100%) HCLv. All 13 IGHV4-34+ HCLs were wild-type. IGHV gene usage in the 11 HCLc BRAF wild-type cases included 5 IGHV4-34, 5 other, and 1 unknown. Our results suggest that HCLv and IGHV4-34+ HCLs have a different pathogenesis than HCLc and that a significant minority of other HCLc are also wild-type for BRAF V600.
Introduction
Molecular testing for genetic alterations in thyroid neoplasms, including BRAF V600E (BRAF) mutation, are often applied to thyroid aspirates falling into the Bethesda System for ...Reporting Thyroid Cytopathology indeterminate categories. Current methods typically use dedicated aspirated material, without morphological determination of containing the cells of interest and may be of elevated cost. We describe our experience with BRAF mutation analysis on material obtained from Papanicolaou (PAP)‐stained ThinPrep® (TP) slides.
Methods
Eighty‐three cases collected between 2012 and 2019 with more than 100 cells were selected. An electronic record of a whole slide scan was made for each case before testing. The coverslips were removed, and DNA was extracted from material scraped from each slide using the Qiagen QIAamp DNA FFPE Tissue Kit. BRAF testing was performed using a highly sensitive mutation detection assay, either COLD‐PCR, castPCR, or droplet digital PCR.
Results
Fourteen out of 83 cases had a BRAF mutation. Of these, 8 were classified as atypia of undetermined significance or suspicious for malignancy in which follow‐up showed conventional papillary thyroid carcinoma in 5 out of 6 cases. The specificity and positive predictive value were 97% and 91%, respectively.
Conclusions
BRAF mutation analysis can be performed on material obtained from routine clinical PAP‐stained TP slides. As a first step, this unconventional effective approach may reduce costs related to the molecular evaluation of thyroid nodule aspirates and provides the opportunity for cytomorphological confirmation that the cells of interest are present in material submitted for BRAF mutation analysis.
The authors performed clinically validated BRAF mutation analysis on thyroid fine needle aspiration material scrapped from routine Papanicolaou‐stained liquid‐based (ThinPrep®) cytology slides. The study shows that BRAF mutation analysis performed on material obtained from Papanicolaou‐stained ThinPrep slides, after initial morphological evaluation and whole slide scan, demonstrates high specificity and high positive predictive value for papillary thyroid carcinoma.
Abstract 931
Hairy cell leukemia (HCL) is a B-cell malignancy with distinctive immunophenotype. Purine analog therapy achieves durable complete remissions in 65–90% of patients. HCL variant (HCLv), ...recognized by the World Health Organization (WHO) as a different disease, lacks CD25, annexin A1 and/or TRAP, and responds poorly to purine analogs with only partial responses (PR) in <50% and lower overall survival (OS) from diagnosis. The recently described HCL variant expressing the immunoglobulin rearrangement IGHV4-34 also has poor response to purine analogs and OS, but can resemble HCL or HCLv immunophenotypically. The V600E BRAF mutation was recently reported present in 100% of 48 patients with HCL and absent in 16 with related disorders including at least 1 case of HCLv. We wished to confirm these results and test well-characterized cases of HCLv and IGHV4-34+ HCL.
DNA was prepared from the blood of 70 patients with HCL and HCLv, 64 of whom were molecularly characterized with respect to IGHV gene usage. The mutation analysis of BRAF c.1799T>A (V600E) and other variants among codons 599–601 within exon 15 was performed using a target-specific mutant allele enriching COLD-PCR technique followed by pyrosequencing. The apparent percentage of mutant versus wild-type alleles was calculated with allele quantification (AQ) mode using PyroMark Software. The threshold AQ value for classifying samples as positive as a mutation was calculated as 3 standard deviations above the mean value of 24 normal blood samples.
Out of 70 total patients tested, 16 (23%) were diagnosed as HCLv based on WHO criteria, and the other 54 were classic HCL. Thirteen (19%) of the 70 cases expressed IGHV4-34, 5 classic HCL and 8 HCLv immunophenotypically. All 6 cases not characterized for IGHV gene usage were classic HCL. The analytic sensitivity of the pyrosequencing assay using cell line controls containing BRAF mutations was <5% tumor cells, and all cases were required to have ≥10% of total white blood cells as HCL. As shown in the table, 28 (40%) of the cases were wild-type with respect to BRAF, including all cases of HCLv. In addition, all 13 cases of IGHV4-34+ HCL, including 5 with classic immunophenotype, were negative for the V600E mutation. Moreover, 7 classic HCL cases were wild-type at V600 of BRAF, including 1 with unknown IGHV and 6 expressing IGHV2-70, IGHV3-15, IGHV3-23, IGHV3-48, IGHV4-39 and IGHV4-59. These 7 cases were relatively resistant to purine analog therapy although numbers were too few for statistical comparisons. In one of these 7 classic HCL cases, CD25 expression had decreased over time.
The V600E BRAF mutation is not present in HCLv or in HCL cases with typical immunophenotype expressing IGHV4-34. A significant minority of other classic HCL cases, 7 (14%) of 49, were negative for the V600E BRAF mutation. It is possible that the V600E BRAF mutation is related to factors other than those affecting immunophenotype, including those influencing prognosis. Additional studies will be needed to better understand the role of V600E-mutated BRAF in HCL and the molecular basis of variants of this disease (Supported in part by NCI, intramural research program, NIH).
Table:BRAF status in patients with classic or variant HCL, with respect to IGHV gene usageV600EWild-typeTotalHCL and IGHV4-34 positive055HCL and IGHV other than IGHV4-3437643HCL and unknown IGHV516HCLv and IGHV4-34 positive088HCLv and IGHV other than IGHV4-34088HCLv and unknown IGHV000Total422870
No relevant conflicts of interest to declare.
Nowadays it is customary to incorporate emotions as explanatory variables of protest participation, since numerous studies have provided evidence for their relevance. However, the incorporation of ...emotions in quantitative research continues to emphasise the effect of a limited set of emotions (normally one or two with negative valence, such as anger or contempt) that are modelled as mediators between non-emotional motives and participation. This makes it difficult to test the joint effect that multiple emotions appear to have, as has been reported in qualitative research. The present research aims to address these gaps in the quantitative literature by applying structural equation modelling to a survey administered to a random sample of 500 inhabitants of a region of Chile in which a long cycle of territorial protests occurred. Our results confirm some hypotheses derived from qualitative research by showing that emotions are in fact experienced in arrays, that emotions with positive valence play a relevant role in explaining participation, and that several emotions mediate the effect of non-emotional motives and participation. It is also clear that emotions experienced by the population are significantly interrelated, thus a study of the direct or mediating effects of any given emotion must also address other emotions experienced intensely by subjects. This evidence could help to modify and improve the way in which emotions are integrated into formal quantitative models of protest participation.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
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