Early Organ Metastasis in Granulomatous Mycosis Fungoides: A Systematic Review.

BACKGROUND: Granulomatous mycosis fungoides (GMF) is a rare form of cutaneous T-cell lymphoma characterized by a granulomatous inflammatory infiltrate. OBJECTIVE: The impact of granulomatous inflammation on the prognosis of the disease remains controversial as there have been both favorable and unfavorable outcomes documented. METHODS: We performed a systematic review of 116 GMF cases previously described in the literature. RESULTS: In contrast to the classic Alibert-Bazin type of mycosis fungoides (MF), cutaneous lesions in GMF tend to involve distal extremities (lower legs, feet, hands) early in the disease course. In the literature, 30% of GMF patients developed organ metastasis, most frequently to the lung. The median time to stage progression was 25 months. CONCLUSION: GMF is an aggressive form of MF. Therefore, screening for distant metastases should be considered at presentation and repeated during follow-up.

The Clinical Utility of FLT3 Mutation Testing in Acute Leukemia: A Canadian Consensus.

FMS-like tyrosine kinase 3 (FLT3) mutations are detected in approximately 20-30% of patients with acute myeloid leukemia (AML), with the presence of a FLT3 internal tandem duplication (FLT3-ITD) mutation being associated with an inferior outcome. Assessment of FLT3 mutational status is now essential to define optimal upfront treatment in both newly diagnosed and relapsed AML, to support post-induction allogeneic hematopoietic stem cell transplantation (alloSCT) decision-making, and to evaluate treatment response via measurable (minimal) residual disease (MRD) evaluation. In view of its importance in AML diagnosis and management, the Canadian Leukemia Study Group/Groupe canadien d'étude sur la leucémie (CLSG/GCEL) undertook the development of a consensus statement on the clinical utility of FLT3 mutation testing, as members reported considerable inter-center variability across Canada with respect to testing availability and timing of use, methodology, and interpretation. The CLSG/GCEL panel identified key clinical and hematopathological questions, including: (1) which patients should be tested for FLT3 mutations, and when?; (2) which is the preferred method for FLT3 mutation testing?; (3) what is the clinical relevance of FLT3-ITD size, insertion site, and number of distinct FLT3-ITDs?; (4) is there a role for FLT3 analysis in MRD assessment?; (5) what is the clinical relevance of the FLT3-ITD allelic burden?; and (6) how should results of FLT3 mutation testing be reported? The panel followed an evidence-based approach, taken together with Canadian clinical and laboratory experience and expertise, to create a consensus document to facilitate a more uniform approach to AML diagnosis and treatment across Canada.

Amyloidosis and Carpal Tunnel Syndrome: Surgical Technique for Extended Carpal Tunnel Release with Tenosynovium and Transverse Carpal Ligament Biopsies.

Carpal tunnel syndrome (CTS) is common in patients with transthyretin amyloidosis (ATTR), and many experience residual symptoms and/or develop recurrent disease following routine carpal tunnel release (CTR). An extended CTR with median nerve neurolysis is recommended for thorough nerve decompression. Tissue confirmation of amyloidosis can be performed at the time of CTR with biopsies of the transverse carpal ligament and/or tenosynovium. Methods: We describe a retrospective, single-center experience performing an extended CTR technique including unilateral and bilateral cases for 13 consecutive patients (18 wrists) with ATTR and symptomatic median neuropathy at the wrist. Results: The mean patient age was 83 (range 67-90) years and 11 (85%) were men. Notable intraoperative findings in all cases included thickened tenosynovium and median nerve epineurium, and adherence of the median nerve to the deep surface of transverse carpal ligament. Pathology findings were positive for amyloidosis from both the transverse carpal ligament and the tenosynovium biopsies in all patients. Conclusions: Extended CTR with simultaneous wrist tissue biopsy can be safely performed for ATTR patients with CTS. Characteristic intraoperative findings should increase clinical suspicion for undiagnosed ATTR and prompt performance of biopsy for diagnostic confirmation. Volar wrist tenosynovial biopsy is our preferred tissue for confirmation of ATTR, for patients with and without CTS, given its safety profile and 100% pathological yield in our series.

Monoclonal Gammopathy of Undetermined Significance in Patients With Transthyretin Amyloidosis (ATTR): Analysis Using the iStopMM Criteria.

INTRODUCTION: To identify the prevalence of monoclonal gammopathy of undetermined significance (MGUS) in patients with transthyretin amyloid (ATTR). We used the iStopMM study revised reference ranges for serum free light-chain (sFLC) corrected for eGFR to identify ATTR patients with light-chain MGUS (LC-MGUS). Characteristics and frequencies of the ATTR cohort with underlying MGUS was compared to a cohort of MGUS patients without ATTR. PATIENTS AND METHODS: A retrospective analysis of ATTR and MGUS patients evaluated at our center between January 2014 to December 2021. A total of 149, predominantly male (87.5%) ATTR patients with a median age of 82 were included. This cohort was compared to 228 MGUS patients. RESULTS: Of the 149 ATTR patients, 27 (18.1%) had coexisting MGUS. Among ATTR patients with MGUS, 12/27 (44%) had LC-MGUS based on sFLC abnormalities assessed using the iStopMM reference ranges. Of the MGUS only cohort, 44/228 (19.3%) met criteria for LC-MGUS. Utilizing the iStopMM reference ranges, 6 ATTR patients did not meet criteria for abnormal sFLCs, uncovering a 20% false-positive rate. CONCLUSION: We noted higher rates of MGUS, particularly LC-MGUS, among ATTR patients when compared to our MGUS only cohort. The high prevalence remained after utilizing the iStopMM sFLC corrected for eGFR reference ranges. Additionally, 6 ATTR patients with renal-dysfunction would have met MGUS criteria if not evaluated using the iStopMM revised measures. These findings emphasize careful interpretation of sFLC abnormalities and encourage providers to keep ATTR on the differential when work-up uncovers sFLC aberrations.

Amyloidosis and COVID-19: experience from an amyloid program in Canada.

Severe acute respiratory syndrome coronavirus (SARS-CoV2) and associated COVID-19 infection continue to impact patients globally. Patients with underlying health conditions are at heightened risk of adverse outcomes from COVID-19; however, research involving patients with rare health conditions remains scarce. The amyloidoses are a rare grouping of protein deposition diseases. Light-chain and transthyretin amyloidosis are the most common disease forms, often present with systemic involvement of vital organs including the heart, nerves, kidneys, and GI tracts of affected individuals. The Amyloidosis Program of Calgary examined 152 ATTR patients and 103 AL patients analyzing rates of vaccination, COVID-19 testing, infection outcomes, influence referrals, and excess deaths. Results showed 15 total PCR-confirmed COVID-19 infections in the tested population of amyloid patients, with a higher frequency of infections among patient with AL compared to the ATTR cohort (26.2% vs 5.1%). Four patients (26.6%) required hospital admission for COVID-19 infection, 2 ATTR, and 2 AL patients. Of the confirmed cases, 1 (0.07%) unvaccinated ATTR patient died of a COVID-19 infection. An excess of deaths was found in both the ATTR and AL cohorts when comparing pre-pandemic years 2018 and 2019 to the pandemic years of 2020 and 2021. The finding suggests that amyloidosis patients are likely at a high risk for severe COVID-19 infection and mortality, especially those of advanced age, those on an active treatment with chemotherapy, and those with concomitant B-cell or plasma cell disorder. The impact of virtual healthcare visits and pandemic measures on the excess of deaths observed requires further research.

NMR-based metabolomic profiling can differentiate follicular lymphoma from benign lymph node tissues and may be predictive of outcome.

Follicular lymphoma (FL) is a cancer of B-cells, representing the second most common type of non-Hodgkin lymphoma and typically diagnosed at advanced stage in older adults. In contrast to the wide range of available molecular genetic data, limited data relating the metabolomic features of follicular lymphoma are known. Metabolomics is a promising analytical approach employing metabolites (molecules < 1 kDa in size) as potential biomarkers in cancer research. In this pilot study, we performed proton nuclear magnetic resonance spectroscopy (1H-NMR) on 29 cases of FL and 11 control patient specimens. The resulting spectra were assessed by both unsupervised and supervised statistical methods. We report significantly discriminant metabolomic models of common metabolites distinguishing FL from control tissues. Within our FL case series, we also report discriminant metabolomic signatures predictive of progression-free survival.

JAK2-tree: a simple CBC-based decision rule to guide appropriate JAK2 V617F mutation testing.

AIMS: The JAK2 V617F mutation is highly recurrent in many of the myeloproliferative neoplasms, a molecular variant that can be easily detected using sensitive and minimally invasive techniques. Given the ease of JAK2 V617F testing, this test may be improperly requested for the purposes of patient 'screening' and to optimise laboratory resource utilisation, it behooves clinicians and laboratorians to perform JAK2 V617F testing only when most appropriate. METHODS: To assist with the screening of patients being considered for JAK2 V617F testing, we developed a clinical decision rule, "JAK2-tree", which can be easily applied to basic CBC parameters (haemoglobin, platelet and white blood cell counts). RESULTS: We tested JAK2-tree on two independent datasets, one an unselected population-based sample (the Copenhagen General Population Study) and the other an historical clinical laboratory referral set, with sensitivities for JAK2 V617F detection of 91% and 94%, respectively. As applied to the historical laboratory referral dataset, moreover, the JAK2-tree algorithm would have reduced JAK2 V617F testing volume over the period of evaluation by 15%. CONCLUSIONS: Our work supports a simple decision-tree-based screening approach to optimize the selection of patients most appropriate for JAK2 V617F testing.

CapTCR-seq: hybrid capture for T-cell receptor repertoire profiling.

Mature T-cell lymphomas consisting of an expanded clonal population of T cells that possess common rearrangements of the T-cell receptor (TCR) encoding genes can be identified and monitored using molecular methods of T-cell repertoire analysis. We have developed a hybrid-capture method that enriches DNA sequencing libraries for fragments encoding rearranged TCR genes from all 4 loci in a single reaction. We use this method to describe the TCR repertoires of 63 putative lymphoma clinical isolates, 7 peripheral blood mononuclear cell (PBMC) populations, and a collection of tumor infiltrating lymphocytes. Dominant Variable (V) and Joining (J) gene pair rearrangements in cancer cells were confirmed by polymerase chain reaction (PCR) amplification and Sanger sequencing; clonality assessment of clinical isolates using BIOMED-2 methods showed agreement for 73% and 77% of samples at the ß and γ loci, respectively, whereas ß locus V and J allele prevalence in PBMCs were well correlated with results from commercial PCR-based DNA sequencing assays (r 2 = 0.94 with Adaptive ImmunoSEQ, 0.77-0.83 with Invivoscribe LymphoTrack TRB Assay). CapTCR-seq allows for rapid, high-throughput and flexible characterization of dominant clones within TCR repertoire that will facilitate quantitative analysis of patient samples and enhance sensitivity of tumor surveillance over time.

T cell clonality assessment: past, present and future.

T cell clonality testing has important clinical and research value, providing a specific and reproducible assessment of clonal diversity in T cell proliferations. Here we review the conceptual foundations of T cell clonality assays, including T cell ontogeny and T cell receptor structure and function; we also provide an introduction to T cell receptor genomics and the concept of the T cell clonotype. This is followed by a review of historical and current methods by which T cell clonality may be assayed, including current assay limitations. Some of these assay limitations have been overcome by employing next-generation sequencing (NGS)-based technologies that are becoming a mainstay of modern molecular pathology. In this vein, we provide an introduction to NGS technologies, including a review of the preanalytical, analytical and postanalytical technologies relevant to T cell clonality NGS assays.

Acute HIV infection presenting as hemophagocytic lymphohistiocytosis: case report and review of the literature.

BACKGROUND: Hemophagocytic lymphohistiocytosis (HLH) is an uncommon systemic inflammatory condition that can result from infections, autoimmune diseases and malignancies. It is a rarely reported life threatening complication of an acute HIV infection, with only ten documented case reports per our literature search. We present a case of HLH secondary to acute HIV infection with a negative HIV antibody-based assay and high plasma viral load. CASE PRESENTATION: A 45 year old male with a past medical history of well controlled hypertension presented with fever, dizziness and non-bloody diarrhea. Initial lab work revealed a new thrombocytopenia, marked renal failure and an elevated creatine kinase, ferritin, lactate dehydrogenase and D-dimer. A bone marrow biopsy revealed HLH. As part of the work up for thrombocytopenia, a rapid HIV antibody based assay was done and was negative. The sample was later routinely tested with a fourth generation antigen/antibody assay as per local protocol and was strongly positive. The plasma RNA viral load was >10,000,000 copies /mL confirming the diagnosis of an acute HIV infection. The patient was urgently started on antiretroviral therapy and recovered. CONCLUSION: This case illustrates a diagnostic approach to HLH which is an uncommon but life threatening multisystem disease, requiring the involvement of a multidisciplinary team of experts. Following any diagnosis of HLH, rapid identification and treatment of the underlying condition is critical. A negative rapid HIV antibody test can be misleading in the context of early HIV infection and the additional use of fourth generation antigen/antibody test or plasma RNA viral load may be required within the right clinical context for diagnosis.

CD10-positive mantle cell lymphoma: biologically distinct entity or an aberrant immunophenotype? Insight, through gene expression profile in a unique case series.

BACKGROUND: Mantle cell lymphoma (MCL) is an aggressive disease with genetic heterogeneity and discrete clinical subtypes. MCL is rarely CD10 positive. These cases raise the question whether a subset of MCL may be germinal centre (GC) derived, and have distinct clinicopathological characteristics. AIMS AND METHODS: A series of nine CD10-positive MCL cases is described herein. The clinicopathological and immunophenotypic features, immunoglobulin somatic hypermutation (SHM) status and gene expression profile (GEP) data are detailed. These features were compared with two independent sets (n=20, each) of CD10-negative MCL cases (controls), which were randomly selected from our institutional registry. RESULTS: GEP showed distinct expression of a GC signature in CD10-positive MCL cases with minimal impact on downstream signalling pathways. There were no significant differences in the clinicopathological features or clinical outcome between our CD10-positive and CD10-negative MCL cases. The frequency of SHM was comparable with established data. CONCLUSIONS: This study provides convincing evidence that CD10 expression is related to a distinct GC signature in MCL cases, but without clinical or biological implications.

PARP1 expression in mantle cell lymphoma: the utility of PARP1 immunohistochemistry and its relationship with markers of DNA damage.

Mantle cell lymphoma (MCL) is an aggressive disease with poor overall survival, attributable in part to frequent defects of the DNA repair genes. In such malignancies, additional inhibition of the ubiquitous DNA damage repair protein, poly-ADP ribose polymerase-1 (PARP1) has shown enhanced cytotoxicity (so-called synthetic lethality). We studied PARP1 expression in a series of clinical cases of MCL, with the secondary aim to ascertain the relationship between PARP1 expression and DNA repair gene expression (namely ATM and p53) by immunohistochemical methods. We also examined the relationship between PARP1 expression and the well-established prognostic biomarker Ki-67, in addition to correlating PARP1 expression with the overall survival. From amongst our series of 79 unselected cases of MCL, we detected PARP1 expression in all but two cases with variable intensity. We also noted correlations between PARP1 expression and ATM and p53 expression. As described in previous studies, we identified a significant survival difference on the basis of Ki-67 and p53 expression. When digital H-score analysis of PARP1 expression was performed, there was a distinct survival advantage noted in patients with lower levels of expression. When our biomarker data were assessed by Cox regression, furthermore, the dominant effects of p53 and PARP1 expression were highlighted. Our data support the need for further research into the potential utility of PARP1 as a biomarker in MCL and for the potential direction of future PARP1 inhibitor-targeted therapy studies.

Protein Expression for Novel Prognostic Markers (Cyclins D1, D2, D3, B1, B2, ITGß7, FGFR3, PAX5) Correlate With Previously Reported Gene Expression Profile Patterns in Plasma Cell Myeloma.

Among plasma cell myeloma (PCM) patients, gene expression profiling (GEP)-based molecular classification has proven to be an independent predictor of survival, after autologous stem cell transplantation. However, GEP has limited routine clinical applicability given its complex methodology, high cost, and limited availability in clinical laboratories. In this study, we have evaluated biomarkers identified from GEP discoveries, utilizing immunohistochemistry (IHC) platform in a cohort of PCM patients. IHC staining for cyclins B1, B2, D1, D2, D3, FGFR3, PAX5, and integrin ß7 (ITGß7) was performed on the bone marrow biopsies of 93 newly diagnosed PCM patients. Expression of FGFR3 was noted in 10 (11%) samples correlating completely with t(4;14)(p16;q32) results (P<0.001); however, the association between FGFR3 and cyclin D2 expression was not significant (P=0.14). ITGß7 expression was present in 9/93 (9%) patients and all these samples also demonstrated upregulated expression of cyclin D2 (P=0.014). Expression of cyclins D1, D2, and D3 was variable in this cohort. Positive protein expression of cyclin D1 was noted in 30/93 (32%), D2 in 17/93 (18%), and D3 in 5/93 (5%) samples. Coexpression of cyclins D1 and D2 was observed in 13/93 (14%) samples, whereas 28 (30%) samples were negative for all the 3 cyclin D proteins. Cyclin B1 was not expressed in any sample, despite adequate staining in positive controls. Cyclin B2 was expressed in 33/93 (35%) and PAX5 protein was noted in 7/93 (8%) samples. In summary, we have demonstrated that mRNA-based prognostic markers can be detected by routine IHC in decalcified bone marrow samples. This approach may provide a useful tool for the wider adoption of prognostic makers for risk stratification of PCM patients. We anticipate that such an approach might allow patients with high-risk immunoprofiles to be considered for other potential novel therapeutic agents, potentially sparing some patients the toxicity of stem cell transplant.

Differential expression of Toll-like receptor (TLR) and B cell receptor (BCR) signaling molecules in primary diffuse large B-cell lymphoma of the central nervous system.

Primary diffuse large B-cell lymphoma of the central nervous system (CNS DLBCL) is a distinct and aggressive lymphoma that is confined to CNS. Since, central nervous system is barrier-protected and immunologically silent; role of TLR/BCR signaling in pathogenesis and biology of CNS DLBCL is intriguing. Genomic mutations in key regulators of TLR/BCR signaling pathway (MYD88/CD79B/CARD11) have recently been reported in this disease. These observations raised possible implications in novel targeted therapies; however, expression pattern of molecules related to TLR/BCR pathways in this lymphoma remains unknown. We have analyzed the expression of 19 genes encoding TLR/BCR pathways and targets in CNS DLBCLs (n = 20) by Nanostring nCounter™ analysis and compared it with expression patterns in purified reactive B-lymphocytes and systemic diffuse large B cell lymphoma (DLBCL) (n = 20). Relative expression of TLR4, TLR5, TLR9, CD79B and BLNK was higher in CNS DLBCLs than in control B-lymphocytes; where as TLR7, MALT1, BCL10, CD79A and LYN was lower in CNS DLBCLs (P < 0.0001). When compared with systemic DLBCL samples, higher expression of TLR9, CD79B, CARD11, LYN and BLNK was noted in CNS DLBCL (>1.5 fold change; P < 0.01). The B cell receptor molecules like BLNK and CD79B were also associated with higher expression of MYD88 dependent TLRs (TLR4/5/9). In conclusion, we have shown over expression of TLR/BCR related genes or their targets, where genomic mutations have commonly been identified in CNS DLBCL. We have also demonstrated that TLR over expression closely relate with up regulation of genes associated with BCR pathway like CD79B/BLNK and CARD11, which play an important role in NF-kB pathway activation. Our results provide an important insight into the possibility of TLR and/or B-cell receptor signaling molecules as possible therapeutic targets in CNS DLBCL.