Profiling of Copy Number Alterations Using Low-Coverage Whole-Genome Sequencing Informs Differential Diagnosis and Prognosis in Primary Cutaneous Follicle Center Lymphoma.

Primary cutaneous follicle center lymphoma (PCFCL) has an excellent prognosis using local treatment, whereas nodal follicular lymphoma (nFL), occasionally presenting with cutaneous spread, often requires systemic therapy. Distinction of the 2 diseases based on histopathology alone might be challenging. Copy number alterations (CNAs) have scarcely been explored on a genome-wide scale in PCFCL; however, they might serve as potential biomarkers during differential diagnosis and risk stratification. Low-coverage whole-genome sequencing is a robust, high-throughput method for genome-wide copy number profiling. In this study, we analyzed 28 PCFCL samples from 20 patients and compared the copy number profiles with a cohort of diagnostic samples of 64 nFL patients. Although the copy number profile of PCFCL was similar to that of nFL, PCFCL lacked amplifications of 18q, with the frequency peaking at 18q21.33 in nFL cases involving the BCL2 locus (PCFCL: 5.0% vs nFL: 31.3%, P = .018, Fisher exact test). Development of distant cutaneous spread was significantly associated with higher genomic instability including the proportion of genome altered (0.02 vs 0.13, P = .033) and number of CNAs (2 vs 9 P = .017), as well as the enrichment of 2p22.2-p15 amplification involving REL and XPO1 (6.3% vs 60.0%, P = .005), 3q23-q24 amplification (0.0% vs 50.0%, P = .004), 6q16.1-q23.3 deletion (6.3% vs 50.0%, P = .018), and 9p21.3 deletion covering CDKN2A and CDKN2B loci (0.0% vs 40.0%, P = .014, all Fisher exact test) in PCFCL. Analysis of sequential tumor samples in 2 cases harboring an unfavorable clinical course pointed to the acquisition of 2p amplification in the earliest common progenitor underlining its pivotal role in malignant transformation. By performing genome-wide copy number profiling on the largest patient cohort to date, we identified distinctive CNA alterations conceivably facilitating the differential diagnosis of PCFCL and secondary cutaneous involvement of nFL and potentially aiding the risk stratification of patients with PCFCL in the future.

Parallel testing of liquid biopsy (ctDNA) and tissue biopsy samples reveals a higher frequency of EZH2 mutations in follicular lymphoma.

BACKGROUND: Recent genomic studies revealed enhancer of zeste homolog 2 (EZH2) gain-of-function mutations, representing novel therapeutic targets in follicular lymphoma (FL) in around one quarter of patients. However, these analyses relied on single-site tissue biopsies and did not investigate the spatial heterogeneity and temporal dynamics of these alterations. OBJECTIVES: We aimed to perform a systematic analysis of EZH2 mutations using paired tissue (tumor biopsies [TB]) and liquid biopsies (LB) collected prior to treatment within the framework of a nationwide multicentric study. METHODS: Pretreatment LB and TB samples were collected from 123 patients. Among these, 114 had paired TB and LB, with 39 patients characterized with paired diagnostic and relapse samples available. The EZH2 mutation status and allele burden were assessed using an in-house-designed, highly sensitive multiplex droplet digital PCR assay. RESULTS: EZH2 mutation frequency was found to be 41.5% in the entire cohort. In patients with paired TB and LB samples, EZH2 mutations were identified in 37.8% of the patients with mutations exclusively found in 5.3% and 7.9% of TB and LB samples, respectively. EZH2 mutation status switch was documented in 35.9% of the patients with paired diagnostic and relapse samples. We also found that EZH2 wild-type clones may infiltrate the bone marrow more frequently compared to the EZH2 mutant ones. CONCLUSION: The in-depth spatio-temporal analysis identified EZH2 mutations in a considerably higher proportion of patients than previously reported. This expands the subset of FL patients who most likely would benefit from EZH2 inhibitor therapy.

Retrospective analysis of chronic myeloid leukemia patients treated in the Department of Internal Medicine and Oncology, Semmelweis University, between 2003 and 2019 / Krónikus myeloid leukaemia miatt 2003 és 2019 között a Semmelweis Egyetem Belgyógyászati és Onkológiai Klinikáján kezelt betegek adatainak elemzése

Összefoglaló. Bevezetés: A krónikus myeloid leukaemia a diagnosztika fejlodésének és a tirozin-kináz-gátlók bevezetésének köszönhetoen az elmúlt évtizedekben kiváló prognózisú betegséggé vált. Célkituzés: A betegséggel kapcsolatos ismereteink nagy része klinikai vizsgálatokból származik, emiatt kiemelt szerepük van a nem szelektált beteganyagon végzett elemzéseknek. Módszer: Retrospektív elemzésünkben a Semmelweis Egyetem Belgyógyászati és Onkológiai Klinikáján 2003 és 2019 között tirozin-kináz-gátló kezelésben részesült betegek adatait tekintettük át. Eredmények: Klinikánkon összesen 88 beteg részesült terápiában, közülük 73 beteg az analízis idopontjában is kezelés alatt állt. A betegek 5 éves össztúlélése 86%, 5 éves progressziómentes túlélése 70% volt. 9 beteg halt meg, közülük 2 betegnél a halál oka a progrediáló alapbetegség volt. 38 betegnél volt szükség az elso vonalban terápiaváltásra, a váltás oka akkor elsosorban az elégtelen terápiás válasz volt. A késobbi terápiaváltásokra elsosorban intolerancia miatt került sor. Az elso vonalban a betegek több mint fele major molekuláris választ ért el, a jelenlegi kezelés mellett a betegek 85%-ánál major molekuláris választ detektáltunk. Megbeszélés: Adataink alapján az intézményünkben kezelt betegek túlélése és a betegek által elért terápiás válasz megfelel a nemzetközi adatoknak. Következtetés: Mivel nem válogatott beteganyagról van szó, a kapott eredmények pontosabb képet adhatnak a krónikus myeloid leukaemia tirozin-kináz-gátlóval történt kezelésének eredményeirol. Orv Hetil. 2021; 162(32): 1297-1302. INTRODUCTION: As a result of advances in diagnostic techniques and the introduction of tyrosine kinase inhibitors, the prognosis of chronic myeloid leukemia has improved over the last decades. OBJECTIVE: Most of our knowledge about chronic myeloid leukemia results from clinical trials, therefore data derived from non-selected patient population is substantial. METHOD: Data of chronic myeloid leukemia patients treated with tyrosine kinase inhibitors at the Department of Internal Medicine and Oncology, Semmelweis University, between 2003 and 2019 were analysed retrospectively. RESULTS: 88 patients received treatment, 73 patients were on therapy at the time of the analysis. Overall survival at 5 years was 86%, progression-free survival at 5 years was 70%. 9 patients died, 2 of them due to progressive disease. 38 patients needed 2nd line therapy, the main reason of treatment change was failure of therapy. Subsequent treatment modifications were conducted mostly because of intolerance. More than half of the patients on 1st line treatment reached major molecular response and 85% of the patients on treatment at the end of the analysis are in major molecular response. DISCUSSION: Based on our data, survival and therapeutic response of patients in our center are similar to the international results. CONCLUSION: This analysis provides real-world data about treatment results of chronic myeloid leukemia in the tyrosine kinase inhibitor era. Orv Hetil. 2021; 162(32): 1297-1302.

Hypercalcemia and renal insufficiency ­ where can we start? / Hypercalcaemia és veseelégtelenség - merre induljunk?

Összefoglaló. Közleményünkben egy 63 éves férfi esetét ismertetjük, aki fáradékonyság, fogyás miatt végzett laboratóriumi vizsgálatokon igazolódó veseelégtelenség és hypercalcaemia miatt került felvételre Klinikánkra. A területen végzett röntgenvizsgálaton a koponyán frontalisan és a sacrumon csonteltérések (temporofrontalisan 13 mm-es, körülírtabb, mérsékelten intenzív árnyék és az S1-es rés sclerosisa) ábrázolódtak, ultrahangvizsgálat során lépmegnagyobbodás volt látható. Tünetei hátterében endokrin vagy malignus betegség nem igazolódott. A háttérben elsosorban myeloma multiplex merült fel, ugyanakkor azt célzott vizsgálatokkal sem megerosíteni, sem kizárni nem lehetett, így csontvelo-biopszia történt. A vesefunkció-romlás okának tisztázása végett vesebiopsziát végeztünk, melynek elozetes eredménye interstitialis nephritist véleményezett óriássejtekkel. Az angiotenzinkonvertáló enzim szérumszintjének ez okból történo vizsgálata emelkedett szintet mutatott, így esetünket Boeck-sarcoidosis extrapulmonalis manifesztációjának tartottuk. Per os szteroidkezelésre a beteg tünetei egyértelmu regressziót mutattak. A csontvelo- és vesebiopszia eredménye megerosítette a Boeck-sarcoidosis diagnózisát. A sarcoidosis ezen extrapulmonalis formája hypercalcaemiával és veseérintettséggel - de tüdoérintettség nélkül - rendkívül ritka, különös tekintettel a vesét érinto formára. Hypercalcaemia nagyjából 7,9%-ban, veseelégtelenség 1,4%-ban fordul elo. Ezen eset alapján fontos hangsúlyozni, hogy a hypercalcaemia és a veseelégtelenség hátterében a gyakoribb endokrin, malignus, hematológiai okok mellett a Boeck-sarcoidosisnak is fel kell merülnie a differenciáldiagnosztika során. Orv Hetil. 2021; 162(13): 514-518. Summary. We present the case of a 63-year-old male patient who was admitted to our Clinic with fatigue, weight loss, hypercalcemia, renal insufficiency and anemia. X-ray showed lesions on the frontal skull and sacral region. On abdominal ultrasound, splenomegaly was detected. Based on these, myeloma multiplex was the most likely initial diagnosis; this, however, could not be confirmed with targeted serum tests, therefore bone marrow biopsy was performed. To clarify the underlying cause of decreased kidney function, renal biopsy was performed, the preliminary results of which revealed interstitial nephritis accompanied by giant cells. Serum angiotensin converting enzyme level was elevated, which led to the diagnosis of Boeck sarcoidosis with extrapulmonary manifestations. Oral corticosteroid therapy was commenced that was followed by regression of the patient's symptoms and laboratory abnormalities. Both the bone marrow and the kidney biopsies supported the diagnosis of Boeck sarcoidosis. Presentation of sarcoidosis with hypercalcemia and renal insufficiency but without the involvement of the lungs is extremely rare. Hypercalcemia occurs in about 7.9% and renal insufficiency in 1.4% of the cases. Based on this case, it is important to highlight that in the background of hypercalcemia and renal failure - beside the more frequent causes such as endocrine and hematological diseases, malignancy - one is to consider the possibility of Boeck sarcoidosis as well. Orv Hetil. 2021; 162(13): 514-518.

Life threatening rare lymphomas presenting as longitudinally extensive transverse myelitis: a diagnostic challenge.

Background and aims - Description of two cases of rare intravascular large B-cell lymphoma and secondary T-cell lymphoma diagnosed postmortem, that manifested clinically as longitudinally extensive transverse myelitis (LETM). We discuss causes of diagnostic difficulties, deceptive radiological and histological investigations, and outline diagnostic procedures based on our and previously reported cases. Case reports - Our first case, a 48-year-old female was admitted to the neurological department due to paraparesis. MRI suggested LETM, but the treatments were ineffective. She died after four weeks because of pneumonia and untreatable polyserositis. Pathological examination revealed intravascular large B-cell lymphoma (IVL). Our second case, a 61-year-old man presented with headache and paraparesis. MRI showed small bitemporal lesions and lesions suggesting LETM. Diagnostic investigations were unsuccessful, including tests for possible lymphoma (CSF flow cytometry and muscle biopsy for suspected IVL). Chest CT showed focal inflammation in a small area of the lung, and adrenal adenoma. Brain biopsy sample from the affected temporal area suggested T-cell mediated lymphocytic (paraneoplastic or viral) meningoencephalitis and excluded diffuse large B-cell lymphoma. The symptoms worsened, and the patient died in the sixth week of disease. The pathological examination of the presumed adenoma in the adrenal gland, the pancreatic tail and the lung lesions revealed peripheral T-cell lymphoma, as did the brain and spinal cord lesions. Even at histological examination, the T-cell lymphoma had the misleading appearance of inflammatory condition as did the MRI. Conclusion - Lymphoma can manifest as LETM. In cases of etiologically unclear atypical LETM in patients older than 40 years, a random skin biopsy (with subcutaneous adipose tissue) from the thigh and from the abdomen is strongly recommended as soon as possible. This may detect IVL and provide the possibility of prompt chemotherapy. In case of suspicion of lymphoma, parallel examination of the CSF by flow cytometry is also recommended. If skin biopsy is negative but lymphoma suspicion remains high, biopsy from other sites (bone marrow, lymph nodes or adrenal gland lesion) or from a simultaneously existing cerebral lesion is suggested, to exclude or prove diffuse large B-cell lymphoma, IVL, or a rare T-cell lymphoma.

Frequent KIT mutations in skin lesions of patients with BRAF wild-type Langerhans cell histiocytosis.

Langerhans cell histiocytosis (LCH) is characterized by mutations of the RAS-RAF-MAPK signaling pathway. We analyzed MAP2K1, NRAS and KIT mutation incidence in skin lesions of BRAF wild-type (wt) LCH patients. We evaluated the occurrence of MAP2K1, NRAS and KIT mutations in seven LCH and one indeterminate cell histiocytosis (ICH) patients. MAP2K1 mutation frequency was found to be 3/7 (42.9%) in LCH and also found in ICH. Similarly, the KIT mutation frequency was found to be equally prevalent (4/7, 57.1%) in LCH and also occurred in ICH. Involvement of KIT exons in LCH-ICH indicated that exon 9/11/18 were equally prevalent followed by exon 13. This exploratory analysis on BRAF-wt LCH revealed a KIT mutation rate comparable to MAP2K1. Although the detected KIT mutations are different from activating mutations found in other KIT-dependent neoplasms, our data suggest that KIT-inhibitors might have a role in treating BRAF-wt LCH patients.

In situ hybridization of feline leukemia virus in a primary neural B-cell lymphoma.

An 8-y-old castrated male, outdoor European shorthair cat was presented with a history of hindlimb weakness and paralysis. Disease progression was continuous from the onset; deep algesia disappeared at the final stage. Radiography of the vertebral column was unremarkable; along with patient history and physical examination results, magnetic resonance imaging suggested inflammatory lesions in the spinal cord, although neoplasia could not be ruled out. Feline leukemia virus (FeLV) positivity was confirmed by a serum ELISA prior to euthanasia. Upon postmortem examination, hemorrhages were present in the spinal cord at the level of vertebrae T7-8. Histologic and immunohistochemical analysis revealed primary diffuse large B-cell lymphoma of the spinal cord with multifocal myelomalacia and hemorrhages. To determine the presence of a pathogen within the lesion, we developed a novel in situ hybridization protocol for FeLV (RNAscope). The reaction revealed large amounts of FeLV viral RNA in the tumor cells.

[Epidemiology of early infections after autologous hematopoietic stem cell transplantation. Analysis of data from 699 patients treated in a Hungarian centre]. / Autológossejt-transzplantációt követo korai infekciók epidemiológiája. Egy hazai centrumban kezelt 699 beteg adatainak elemzése.

Introduction: Autologous hemopoietic stem cell transplantation remains a promising therapy in certain malignant and non-malignant conditions. The procedure, however, will increase the risk of complications, most notably early and late infections. Aim: To analyze the frequency and spectrum of pathogens in early (<+100 days) post-transplant infections and to evaluate risk factors for mortality. Method: Prospectively collected data from 699 patients undergoing autologous hemopoietic stem cell transplantation between 2007 and 2014 at our center were retrospectively reviewed and analyzed. Results: The median age of 699 patients was 56 (interquartile range: 43-62) years, 54% (376) were male. 25 patients have been transferred to other centers and 19 patients were lost to follow up. Neutropenic fever occurred in 69.8% (488) of patients. In addition, 102 infectious episodes in 96 patients were identified. Most commonly bacteremia occurred (49 episodes) with a median onset of 7 (5-11) days. The majority (33/49) of bacteremias have been observed during the pre-engraftment period. Their incidence proved to be higher in patients with malignant lymphoma compared to individuals with plasma cell disorders (p = 0.0005, OR: 2.41, 95% CI: 1.49-3.99). 12 episodes of viral infections and 8 cases of proven or probable invasive mycoses have been identified. Among the 655 patients with complete follow up, 16 in-hospital deaths (2.4%) occurred, 8 of them were associated with infections. Survival was adversely affected by early infections (p = 0.0001). Conclusion: In autologous stem cell transplantation, microbiologically unconfirmed neutropenic fever is common. Documented early bacteremia, however, is infrequent. Lymphoma patients have a significantly higher chance to develop bloodstream infections compared to individuals with plasma cell disorders. Early infections decrease the chance of survival; thus, an effective prophylaxis and therapy remains of paramount importance. Orv Hetil. 2020; 161(3): 103-109.

Lymphomatoid Papulosis Type B in a Patient with Crohn's Disease Treated with TNF-Alpha Inhibitors Infliximab and Adalimumab.

Dear Editor, Lymphomatoid papulosis (LP) is a chronic, recurrent, usually self-limited papulonecrotic or papulonodular skin disease, which belongs to the group of primary cutaneous CD30+ lymphoproliferative disorders (1). Three main histological subtypes of LP have been recognized: type A (histiocytic), type B (mycosis fungoides-like), and type C (anaplastic large cell lymphoma-like). Recently, new histologic LP variants classified as type D (CD8-positive, cytotoxic form) and type E (angioinvasive form) have also been described. The etiology of LP has not been determined to date (2-4). Herein we report a case of LP type B evolving in a patient with Crohn's disease after treatment with infliximab and adalimumab. A 38-year-old man suffering from terminal ileitis form of luminar Crohn's disease for 10 years presented at our department. During the last 10 years, the patient had been treated with a number of conventional disease-modifying anti-inflammatory drugs including non-steroid anti-inflammatory drugs, mesalazine, and immunomodulatory agents such as corticosteroids and azathioprine. As the disease was not sufficiently controlled, TNF-α inhibitor therapy was initiated. Infliximab was administered in standard dosage (5 mg/kg body weight every 8 weeks after the induction period) for one year. Concomitant therapy with azathioprine was established to reduce the risk of adverse immunological reactions. Since the patient showed only partial clinical response, infliximab was switched to adalimumab (40 mg biweekly), resulting in notable improvement. 18 months after the initiation of adalimumab treatment, asymptomatic, small, red to brown papules developed on the extremities. Multiple lesions were observed, initially on the legs, but the symptoms rapidly progressed to the arms and trunk (Figure 1). An acquired ichthyosis further complicated the disease course by extended, extremely xerotic, scaling skin lesions. Neither systemic symptoms nor significant lymphadenopathy was observed. The clinical picture suggested either ichthyosiform mycosis fungoides or a coincidence of LP and acquired ichthyosis. The histology of a typical papule showed perivascular and periadnexal lymphoid infiltration with massive hemorrhage in the dermis. The infiltration was dense, composed of small-to-medium-sized lymphoid cells showing focal significant epidermotropism (Figure 2). Most observed epidermal lymphocytes were CD3+, CD4+, and CD30+, while the dermal infiltration had higher CD4 and lower CD30 expression (10-15%). Polymerase chain reaction (PCR) analysis of skin and peripheral blood samples did not show clonal rearrangement of T-cell receptor gamma (TcRgamma) genes. Normal phenotypes of lymphocyte subsets were detected by flow cytometry of peripheral blood. Ichthyosiform mycosis fungoides was excluded since histology of ichthyosiform skin lesions showed only hyperkeratosis with a reduced granular layer. While the cutaneous CD4+ epidermotropic infiltrate was suspicious of either mycosis fungoides or LP type B, the complexity of clinicopathological data confirmed the diagnosis of LP type B. The peripheral blood counts, serum biochemical tests, and urinalysis were within normal range, while the elevated serum anti-Saccharomyces cerevisiae antibodies (ASCA) of IgG and IgA subclasses indicated the activity of Crohn's disease. Adalimumab and azathioprine were discontinued, and oral budesonide therapy was started in combination with topical corticosteroids and PUVA phototherapy. The skin lesions resolved with hyperpigmentation, and there was no relapse during the twelve-month follow-up. Recent data suggest that LP occurs more commonly in immunocompromised patients, especially in those with solid organ or bone marrow transplants (3). Though TNF-α inhibitors have dramatically advanced the treatment of various diseases, the risk of lymphoma associated with their use remains controversial (5). Several cases of cutaneous lymphoproliferative disorders associated with TNF-α inhibitor treatment have been reported, including two patients with LP (6). One of the two patients with LP received infliximab for Crohn's disease (7), while the other one had juvenile rheumatoid arthritis and received adalimumab (8). Our case is the third report on LP developing under TNF-α inhibitor therapy and the first LP type B in a patient with Crohn's disease treated with infliximab and later with adalimumab. A further interesting aspect of our case is that it also represents an example of the known association of acquired ichthyosis with inflammatory bowel disease (9). Multidisciplinary management was needed to provide optimal care and disease outcome for our patient. Since it is usually difficult to prove causality in most of such cases, it is important to collect similar clinical observations. Acknowledgments: The authors are grateful to Dr. László Bene, Dr. József Szakonyi, and Dr. Fruzsina Kovács for additional medical care of the patient and to Tamás Szaák for the clinical photos. The authors thank Prof. Miklós Sárdy for his critical review of the paper.

Calreticulin mutation specific CAL2 immunohistochemistry accurately identifies rare calreticulin mutations in myeloproliferative neoplasms.

Mutations of the multifunctional protein calreticulin (CALR) are recognised as one of the main driver alterations involved in the pathogenesis of Philadelphia negative myeloproliferative neoplasms (Ph- MPN) and also represent a major diagnostic criterion in the most recent World Health Organization classification of myeloid neoplasms. Nowadays, quantitative assessment of the driver mutations is gaining importance, as recent studies demonstrated the clinical relevance of the mutation load reflecting the size of the mutant clone. Here, we performed for the first time a manual and automated quantitative assessment of the CALR mutation load at protein level using CAL2, a recently developed CALR mutation specific monoclonal antibody, on a cohort of 117 patients with essential thrombocythemia (ET) or primary myelofibrosis (PMF) and compared the CALR protein mutation loads with the CALR mutation load values established by a molecular assay. Eighteen different CALR mutations were detected in the cohort of the 91 CALR mutant cases. Mutation loads of the CALR mutations were between 13% and 94% with mean value in PMF cases significantly higher than ET cases (49.94 vs 41.09; t-test, p=0.004). Cases without CALR mutation (n=26) showed no or only minimal labelling with the CAL2 antibody, while all 18 different types of CALR mutations were associated with CAL2 labelling. The CALR mutation load showed a significant correlation (p=0.03) with the occurrence of major thrombotic events, with higher mutation load in patients presenting with these complications. We report a 100% concordance between the mutation status determined by immunohistochemistry and the CALR molecular assay, and we extend the applicability of this approach to 16 rare CALR mutations previously not analysed at protein level.

[Change in paradigm in the treatment of pediatric acquired bone marrow failure syndromes in Hungary]. / Korszakváltás a gyermekkori szerzett csontvelo-elégtelenséggel járó kórképek kezelésében Magyarországon.

INTRODUCTION: Acquired bone marrow failures are rare but fatal diseases in childhood. Since 2013, Hungary has been participating as a full member in the work of the European Working Group on uniform diagnostics and therapy in patients with acquired bone marrow failure syndromes. Hypocellular refractory cytopenia of childhood has been emphasized as a frequent entity, transplanted by reduced intensity conditioning with excellent outcomes. AIM: To analyse and compare the results of treatment before and after our joining. METHOD: A total of 55 patients have been treated in the 8 centres of the Hungarian Pediatric Oncology Network during 5 years between 2013 and 2017 (severe aplastic anemia: 9, myelodysplastic syndrome: 41, juvenile myelomonocytic leukemia: 5 patients). Allogeneic hematopoietic stem cell transplantation was performed in severe aplastic anemia in 7 cases, while antithymocyte globulin was administered in one case and one patient died before diagnosis. In patients with myelodysplastic syndromes, watch and wait strategy was applied in 4, while transplantation in 37 cases. Reduced intensity conditioning was used in 54 percent of these cases. Transplantation was the treatment of choice in all 5 patients with juvenile myelomonocytic leukemia. RESULTS: In the whole patient cohort, the time from diagnosis to treatment was median 92 (3-393) days, while in severe aplastic anemia median 28 (3-327) days only. Grade II-IV acute graft versus host disease occurred in 22.6%, grade III-IV in 6.8% and chronic in 11.2%. All the patients treated with severe aplastic anemia are alive and in complete remission (100%). The overall estimated survival rate is 85.1% in myelodysplastic syndrome, while 75% in juvenile myelomonocytic leukemia. The median follow-up was 30.4 (1.1-62.5) months. There was a remarkable increase in overall survival comparing the data before (1992-2012) and after (2013) joining the international group, 70% vs. 100% (p = 0.133) in severe aplastic anemia and 31.3% vs. 85.1% (p = 0.000026) in myelodysplastic syndrome. CONCLUSION: Due to a change in the paradigm of the conditioning regimen in hypocellular refractory cytopenia of childhood, the overall survival rate has significantly increased. Orv Hetil. 2018; 159(42): 1710-1719.

Concomitant 1p36 deletion and TNFRSF14 mutations in primary cutaneous follicle center lymphoma frequently expressing high levels of EZH2 protein.

Primary cutaneous follicle center lymphoma (PCFCL) is an indolent variant of follicular lymphoma (FL) with limited information available on the genetic background of the disease. The genetic hallmark of nodal FL, the t(14;18) translocation, affecting the BCL2 gene, is rare in PCFCL. Loss of 1p36, the most common secondary chromosomal abnormality in nodal FL, has been recently reported in 16.7% of PCFCL cases. In order to further characterize PCFCL, 21 cases were analyzed using interphase fluorescence in situ hybridization with BCL2 break apart and 1p36/1q25 dual color probes. Sanger sequencing was used to investigate TNFRSF14 and EZH2 mutations and immunohistochemistry to assess BCL2, EZH2 protein expressions.1p36 deletion occurred in 22% (5/21), BCL2 gene break in 10% (2/20) of the PCFCL cases. Mutations of the candidate tumor suppressor gene of the 1p36 region, TNFRSF14 mutations were detected in 4/17 (23.5%) cases with 2 cases presenting with concurrent 1p36 deletion. EZH2 hotspot mutations at Y641, A682, and A692 were not found. High EZH2 protein expression associated with a BCL2 negative phenotype was observed in 43% (9/21) of the cases. BCL2 gene break or 1p36 deletion did not impact the prognosis; however, they showed association with advanced stages at diagnosis (p = 0.016) and a tendency with shorter event free survival (p = 0.052).In conclusion, 1p36 deletion co-occurs with acquired TNFRSF14 mutations, suggesting a role of this tumor suppressor gene in the development of a subgroup of PCFCL. High EZH2 protein expression associated with BCL2 negative phenotype is common and might represent an ideal therapeutic target.

[Systemic mastocytosis with progressive disease course]. / Progresszív kórlefolyást mutató szisztémás mastocytosis.

Authors report on a case of a male patient of systemic mastocytosis that was associated with extensive cutaneous lesions. Chronic diarrhoea worsening his quality of life was well managed by the administration of antihistamines. The pleural fluid recurrence soon after drainage has been controlled by the administration of alpha interferon. 40 years after the onset of the first skin signs progression has been manifested in the development of "B" (bone marrow infiltration rate >30%, dysmyelopoiesis, serum tryptase >20 µg/L, hepato- and splenomegaly) and "C" symptoms (liver function test abnormalities, cytopenia, malabsorption, osteoporosis). The patient died at age of 87. The authors' aim was to attract attention on this rare disease and emphasize that symptomatic therapy with antihistamines and drugs available based on customised rights by the National Health Insurance Fund might provide good quality of life. Orv Hetil. 2018; 159(5): 192-196.

Quantitative assessment of JAK2 V617F and CALR mutations in Philadelphia negative myeloproliferative neoplasms.

BACKGROUND: Philadelphia negative myeloproliferative neoplasms (MPNs) are characterized by frequent mutations of driver genes including JAK2, CALR and MPL. While the influence of JAK2 V617F mutant allele burden on the clinical phenotype of MPN patients is well-described, the impact of CALR mutant allele burden on clinical features needs further investigation. PATIENTS AND METHODS: Quantitative assessment of JAK2 and CALR mutations was performed on diagnostic DNA samples from 425 essential thrombocythemia (ET) and 227 primary myelofibrosis patients using real-time quantitative PCR and fragment length analysis. Characterization of CALR mutations and detection of MPL mutations were performed by Sanger sequencing. RESULTS: Twelve novel CALR mutations have been identified. ET patients with CALRmut load exceeding the median value exhibited lower hemoglobin values (12.0 vs. 13.6 g/dL), higher LDH levels (510 vs. 351 IU/L) and higher rate of myelofibrotic transformation (19% vs. 5%). The CALRmut load was higher among ET patients presenting with splenomegaly compared to those without splenomegaly (50.0% vs. 43.5%). CONCLUSION: Our study confirms the clinical significance of driver mutational status and JAK2mut load in MPNs; in addition, unravels a novel clinical association between high CALRmut load and a more proliferative phenotype in ET.

Familial Acute Myeloid Leukemia and Myelodysplasia in Hungary.

Although genetic predisposition to haematological malignancies has long been known, genetic testing is not yet the part of the routine diagnostics. In the last ten years, next generation sequencing based studies identified novel germline mutations in the background of familial aggregation of certain haematologic disorders including myelodysplastic syndromes (MDS) and acute myeloid leukaemia (AML). This is supported by the fact that the myeloid neoplasms with genetic predisposition represent a new category in the revised 2016 World Health Organization classification. According to the new classification, these disorders are subdivided based on the clinical and genetic features, including myeloid neoplasms with germline predisposition alone, or with pre-existing platelet disorder, cytopaenias or other organ failures. The predisposing genetic factors include mutations in the RUNX1, CEBPA, GATA2, ANKRD26, ETV6, DDX41, TERC or TERT and SRP72 genes. The genes affected in these syndromes are important regulators of haemopoiesis and are frequently implicated in leukaemogenesis, providing deeper insight into the understanding of normal and malignant haemopoiesis. Despite the growing knowledge of germline predisposing events in the background of familial myeloid malignancies, the germline genetic component is still unknown in a subset of these pedigrees. Here, we present the first study of inherited myeloid malignancies in Hungary. We identified three families with apparent clustering of myeloid malignancies with nine affected individuals across these pedigrees. All tested individuals were negative for CEBPA, GATA2, RUNX1, ANKRD26, ETV6, DDX41, TERC or TERT and SRP72 mutations, suggesting the presence of so far unidentified predisposing mutations.

Recurrent somatic JAK-STAT pathway variants within a RUNX1-mutated pedigree.

Germline variants within the transcription factor RUNX1 are associated with familial platelet disorder and acute leukemia in over 40% of carriers. At present, the somatic events triggering leukemic transformation appear heterogeneous and profiles of leukemia initiation across family members are poorly defined. We report a new RUNX1 family where three sisters harboring a germline nonsense RUNX1 variant, c.601C>T (p.(Arg201*)), developed acute myelomonocytic leukemia (AML) at 5 years of age. Whole-exome sequencing of tumor samples revealed all three siblings independently acquired variants within the JAK-STAT pathway, specifically targeting JAK2 and SH2B3 (a negative regulator of JAK2), while also sharing the 46/1 haplotype linked with sporadic JAK2-positive myeloproliferative neoplasms. In-depth chromosomal characterization of tumors revealed acquired copy number gains and uniparental disomy amplifying RUNX1, JAK2 and SH2B3 variants, highlighting the significance of co-operation between these disrupted pathways. One sibling, presenting with myelodysplasia at 14 years, had no evidence of clonal or subclonal JAK2 or SH2B3 variants, suggesting the latter were specifically associated with leukemic transformation in her sisters. Collectively, the clinical and molecular homogeneity across these three young siblings provides the first notable example of convergent AML evolution in a RUNX1 pedigree, with the recurrent acquisition of JAK-STAT pathway variants giving rise to high-risk AML, characterized by chemotherapy resistance and relapse.

[The role of driver and subclonal mutations in pathogenesis of primary myelofibrosis]. / A driver és szubklonális mutációk szerepe a primer mielofibrózis patogenezisében.

Primary myelofibrosis (PMF) is a Philadelphia chromosome negative, clonal myeloproliferative neoplasm characterised by a progressive nature. Morphologically, the bone marrow biopsy shows features of abnormal proliferation of terminally differentiated megakaryocytes and subsequent bone marrow fibrosis. The molecular landscape of PMF includes phenotypic driver mutations (JAK2 V617F, CALR and MPL) which represent major diagnostic criteria, and subclonal mutations that also occur in several other myeloid diseases, but have a prognostic value in disease progression of MF. The most important subclonal mutations affect the genes ASXL1, TET2, IDH1/2, EZH2 and TP53. Triple negative genotype and the high molecular risk genotype and CALR-/ASXL1+ are associated with adverse survival with the latest indicating stem cell transplantation independently of the DIPSS-plus score.

Effective BRAF inhibitor vemurafenib therapy in a 2-year-old patient with sequentially diagnosed Langerhans cell histiocytosis and Erdheim-Chester disease.

Erdheim-Chester disease (ECD) is a rare histiocytic disorder, characterized by the xanthomatous infiltration of tissues by CD68-positive and CD1a-/CD100-negative foamy histiocytes. In childhood, ECD is exceptionally rare, and only a dozen cases have been published so far. The cooccurence of Langerhans cell histiocytosis (LCH) and ECD is even rarer. Here, we report a 2-year-old boy, the youngest patient in the literature so far, who was diagnosed with concomitant BRAF mutation-positive LCH and ECD. In his case, conventional LCH treatment proved to be ineffective, but he is the youngest patient who was successfully treated with the BRAF inhibitor vemurafenib.