Histiocytosis following T-acute lymphoblastic leukemia: A BFM study

Case Report: Coexistence of Rosai-Dorfman disease and B-cell acute lymphoblastic leukemia in an adolescent

Rosai-Dorfman disease (RDD) is an unusual, non-malignant proliferative disorder involving non-Langerhans cell histiocytes, characterized by a wide range of clinical presentations and distinctive atypical morphological patterns. The concurrent manifestation of acute lymphoblastic leukemia (ALL) alongside RDD is exceptionally rare. Here, we present the case of a 14-year-old male patient diagnosed with ALL who, during the consolidation phase of chemotherapy, developed multifocal bone, dural, and liver lesions, as confirmed through CT and MRI imaging. Histopathological evaluations of the bone and liver lesions identified features consistent with Rosai-Dorfman disease. To the best of our knowledge, this case represents the first reported instance of RDD co-occurring with high-risk pre-B-cell ALL in an adolescent undergoing chemotherapy. Unfortunately, the patient experienced a relapse of ALL and died due to a fungal infection. In this report, we analyze the distinct clinical features and disease progression of both conditions and offer an extensive review of relevant literature.

A novel mutation of LYST and haemophagocytic lymphohistiocytosis as the first symptom in children with ph+ALL: A case report and literature review

Haemophagocytic lymphohistiocytosis (HLH) is a rare disorder. This study sheds light on a rare and intriguing case of HLH as the initial symptom in a child with Philadelphia chromosome-positive acute lymphoblastic leukaemia (ph+ALL). This case report, accompanied by a comprehensive literature review, highlights the diagnostic challenges and treatment complexities encountered in the management of such rare manifestations. Moreover, the identification of a novel mutation in the LYST gene adds a unique genetic perspective to the understanding of HLH pathogenesis, potentially opening avenues for further research in this area.

Hemophagocytic Lymphohistiocytosis in the Context of Hematological Malignancies and Solid Tumors

Hemophagocytic lymphohistiocytosis (HLH) has been described for decades in association with malignancies (M-HLH). While its mechanism is unknown, M-HLH has a poor prognosis, ranging from 10% to 30% overall survival. Mature T-cell lymphomas, diffuse large B-cell lymphoma, and Hodgkin lymphoma, with or without viral co-triggers such as Epstein-Barr virus, are among the most frequent underlying entities. Most M-HLH cases occur at the presentation of malignancy, but they may also occur during therapy as a result of immune compromise from chemotherapy (HLH in the context of immune compromise, IC-HLH) and (typically) disordered response to infection or after immune-activating therapies (Rx-HLH, also known as cytokine release syndrome, CRS). IC-HLH typically occurs months after diagnosis in the context of fungal, bacterial, or viral infection, though it may occur without an apparent trigger. Rx-HLH can be associated with checkpoint blockade, chimeric antigen receptor T-cell therapy, or bispecific T-cell engaging therapy. Until recently, M-HLH diagnosis and treatment strategies were extrapolated from familial HLH (F-HLH), though optimized diagnostic and therapeutic treatment strategies are emerging.

Langerhans cell histiocytosis developing acute lymphoblastic leukemia

The sequential occurrence of Langerhans cell histiocytosis and acute leukemia in only one individual has been reported previously; however, it is rarely observed that Langerhans cell histiocytosis can transform into acute lymphoblastic leukemia, and the underlying mechanisms remain unclear. In this report, we have analyzed a case of acute lymphoblastic leukemia converted from Langerhans cell histiocytosis using high-throughput sequencing method, and found that mitogen-activated protein kinase gene mutation, which can act as a marker for poor prognosis, might be involved in disease transformation. This is the first description about acute lymphoblastic leukemia B-cell type after Langerhans cell histiocytosis diagnosis and therapy in China.

Aggressive Langerhans cell histiocytosis following T-cell acute lymphoblastic leukemia

A 4-year-old female child developed cutaneous Langerhans cell histiocytosis 6 months following a diagnosis of T-cell acute lymphoblastic leukemia. Imaging revealed no evidence of systemic disease. Seven months later, the first systemic lesion was discovered on laryngoscopy. Restaging Positron Emission Tomography - Computed Tomography at that time revealed new 18-fluorodeoxyglucose-positive lesions in the left apical pleural margin, right lower peri-esophageal region, left ventricular myocardium, pancreas, upper pole of the left kidney, and inguinal and gluteal regions consistent with progressive systemic disease. Genomic testing revealed a low tumor mutational burden as well as mutations in KRAS G12A, ARID1A Q524, CDKN2A/B loss, and an alteration in NOTCH1.

STIM1 and STIM2 Mediate Cancer-Induced Inflammation in T Cell Acute Lymphoblastic Leukemia

T cell acute lymphoblastic leukemia (T-ALL) is commonly associated with activating mutations in the NOTCH1 pathway. Recent reports have shown a link between NOTCH1 signaling and intracellular Ca2+ homeostasis in T-ALL. Here, we investigate the role of store-operated Ca2+ entry (SOCE) mediated by the Ca2+ channel ORAI1 and its activators STIM1 and STIM2 in T-ALL. Deletion of STIM1 and STIM2 in leukemic cells abolishes SOCE and significantly prolongs the survival of mice in a NOTCH1-dependent model of T-ALL. The survival advantage is unrelated to the leukemic cell burden but is associated with the SOCE-dependent ability of malignant T lymphoblasts to cause inflammation in leukemia-infiltrated organs. Mice with STIM1/STIM2-deficient T-ALL show a markedly reduced necroinflammatory response in leukemia-infiltrated organs and downregulation of signaling pathways previously linked to cancer-induced inflammation. Our study shows that leukemic T lymphoblasts cause inflammation of leukemia-infiltrated organs that is dependent on SOCE.

Histiocytic cell neoplasms involving the bone marrow: summary of the workshop cases submitted to the 18th Meeting of the European Association for Haematopathology (EAHP) organized by the European Bone Marrow Working Group, Basel 2016

The bone marrow is a preferential site for both reactive and neoplastic histiocytic proliferations. The differential diagnosis ranges from reactive histiocyte hyperplasia in systemic infections, vaccinations, storage diseases, post myeloablative therapy, due to increased cell turnover, and in hemophagocytic lymphohistiocytosis, through extranodal Rosai-Dorfman disease to neoplasms derived from histiocytes, including histiocytic sarcomas (HS), Langerhans cell histiocytoses (LCH), Erdheim-Chester disease (ECD), and disseminated juvenile xanthogranuloma (JXG). One of the most important recent developments in understanding the biology of histiocytic neoplasms and in contributing to diagnosis was the detection of recurrent mutations of genes of the Ras/Raf/MEK/ERK signaling pathway, in particular the BRAF^V600E mutation, in LCH and ECD. Here, we summarize clinical and pathological findings of 17 histiocytic neoplasms that were presented during the bone marrow symposium and workshop of the 18th European Association for Haematopathology (EAHP) meeting held in Basel, Switzerland, in 2016. A substantial proportion of these histiocytic neoplasms was combined with clonally related lymphoid (n = 2) or myeloid diseases (n = 5, all ECD). Based on the latter observation, we suggest excluding co-existent myeloid neoplasms at initial staging of elderly ECD patients. The recurrent nature of Ras/Raf/MEK/ERK signaling pathway mutations in histiocytic neoplasms was confirmed in 6 of the 17 workshop cases, illustrating their diagnostic significance and suggesting apotential target for tailored treatments.

A systematic review of malignancy-associated hemophagocytic lymphohistiocytosis that needs more attentions

As an infrequent but potentially life-threatening hyperinflammatory syndrome, hemophagocytic lymphohistiocytosis (HLH) is clinically characterized with prolonged fever, hepatosplenomegaly, cytopenia, hypertriglyceridemia, hyperferritinemia and hemophagocytosis in bone marrow, liver, spleen or lymph nodes. Malignancy-associated HLH (M-HLH), one type of acquired HLH, usually presents variable overlaps of symptoms with other types of HLH, thus resulting in higher incidence of misdiagnosis and mortality. In recent years, with the increasing awareness to this disease, the diagnosis and management of HLH have gained more and more attention, and improvements have been made accordingly. As a result, the survival of patients is greatly prolonged. However, there is still no consensus on the diagnostic criteria and treatment strategies due to lack of large samples or prospective clinical trials. In order to improve recognition and diagnosis, and provide guidance regarding the treatment of M-HLH, the Study Group in HLH Subtypes of the Histiocyte Society has developed consensus recommendations for the diagnosis and management of M-HLH in 2015. In the present article, we summarized and discussed some updated understandings in M-HLH.

Histiocytic and dendritic cell neoplasms: what have we learnt by studying 67 cases

Tumors derived from histiocytic and dendritic cells encompass a large and heterogeneous group of neoplastic and reactive conditions, and their diagnosis is challenging both for pathologists and clinicians. Diagnosis is based on morphological and phenotypical findings, but hybrid features are not uncommon. Furthermore, recent studies uncovered the molecular mechanisms driving some of these tumors, improving diagnostic adequacy, and providing the basis for effective therapeutic breakthroughs.Sixty-seven cases were submitted to the accessory cell and histiocytic neoplasms session at the European Association of Haematopathology/Society for Hematopathology workshop 2016 held in Basel, Switzerland. The cases included histiocytic sarcomas (HS), Langerhans cell tumors (LCT), Erdheim-Chester disease, interdigitating dendritic cell sarcomas (IDCS), indeterminate dendritic cell tumors (IND-DCT), follicular dendritic cell sarcomas, and blastic plasmacytoid dendritic cell neoplasms. Rosai-Dorfman disease and, more rare, conditions such as ALK-positive histiocytosis were also submitted. These cases illustrated classical and unexpected features at morphological, phenotypical, and molecular levels, providing a valuable compendium for pathologists confronting with these tumors.The paper summarizes the most notable features of every single group of diseases, with comments about the most challenging issues, in the attempt to provide practical indications for their recognition.

Hemophagocytosis by Leukemic Blasts in T Cell Acute Lymphoblastic Leukemia: An Unusual Finding

Hemophagocytosis shows engulfment of hematopoietic cells by histiocytes and is a property generally associated with cells of the histiocytic lineage. It can be familial or is seen in a wide spectrum of acquired disorders. Hemophagocytosis by leukemic blasts is an uncommon phenomenon and has been reported mainly in acute myeloid leukemia. Its association with acute lymphoblastic leukemia is rare. We present a case of hemophagocytosis by blasts in the bone marrow in a 11 year old boy with T cell-acute lymphoblastic leukemia.

Consensus recommendations for the diagnosis and management of hemophagocytic lymphohistiocytosis associated with malignancies

The hyperinflammatory syndrome hemophagocytic lymphohistiocytosis can occur in the context of malignancies. Malignancy-triggered hemophagocytic lymphohistiocytosis should be regarded separately from hemophagocytic lymphohistiocytosis during chemotherapeutic treatment, which is frequently associated with an infectious trigger. The substantial overlap between the features of hemophagocytic lymphohistiocytosis with features of neoplasms makes its identification difficult when it occurs in malignant conditions. To facilitate recognition and diagnostic workup, and provide guidance regarding the treatment of malignancy-associated hemophagocytic lymphohistiocytosis, consensus recommendations were developed by the Study Group on Hemophagocytic Lymphohistiocytosis Subtypes of the Histiocyte Society, an interdisciplinary group consisting of pediatric and adult hemato-oncologists and immunologists.

B-acute lymphoblastic leukemia/lymphoblastic lymphoma

OBJECTIVES

This session of the 2013 Society of Hematopathology/European Association for Haematopathology Workshop was dedicated to B-acute lymphoblastic leukemia (B-ALL)/lymphoblastic lymphoma (LBL) with recurrent translocations and not otherwise specified.

METHODS

In this review, we summarize the cases discussed during the workshop, review the pertinent and most recent literature on the respective topics, and provide a few key points that may aid in the workup of patients with B-ALL/LBL.

RESULTS

Many of the submitted cases showed interesting diagnostic, immunophenotypic, or clinical aspects of B-ALL with BCR/ABL1, MLL-associated, and other recurrent chromosomal abnormalities. Several cases showed rare aberrancies such as coexistent IGH/BCL2 and MYC rearrangements and raised issues in classification. Other cases had unusual clinical presentations, including B-ALL with hypereosinophilia and therapy-related B-ALL. Several cases highlighted the role of flow cytometry immunophenotyping in distinguishing benign B-cell precursors from aberrant lymphoblasts, and other cases raised questions regarding the clinical importance of myeloperoxidase positivity in acute lymphoblastic leukemia.

CONCLUSIONS

The complexity and spectrum of cases presented in this review highlight the importance of clinicopathologic correlation and the value of ancillary studies in the classification and workup of patients with B-ALL/LBL.

Malignancy-associated haemophagocytic lymphohistiocytosis in children and adolescents

Haemophagocytic lymphohistiocytosis (HLH) in the context of malignancy is mainly considered a challenge of adult haematology. While this association is also observed in children, little is known regarding inciting factors, appropriate treatment and prognosis. We retrospectively analysed 29 paediatric and adolescent patients for presenting features, type of neoplasm or preceding chemotherapy, treatment and outcome. Haemophagocytic lymphohistiocytosis was considered triggered by the malignancy (M-HLH) in 21 patients, most of whom had T- (n = 12) or B-cell neoplasms (n = 7), with Epstein-Barr virus as a co-trigger in five patients. In eight patients, HLH occurred during chemotherapy (Ch-HLH) for malignancy, mainly acute leukaemias (n = 7); an infectious trigger was found in seven. In M- and Ch-HLH, median overall survival was 1·2 and 0·9 years, and the 6 month survival rates were 67% and 63%, respectively. Seven of 11 deceased M-HLH patients exhibited active malignancy and HLH at the time of death, while only two out of five deceased Ch-HLH patients had evidence of active HLH. To overcome HLH, malignancy- and HLH-directed treatments were administered in the M-HLH cohort; however, it was not possible to determine superiority of one approach over the other. For Ch-HLH, treatment ranged from postponement of chemotherapy to the use of etoposide-containing regimens.

Clonal Relationships Between Malignant Lymphomas and Histiocytic/Dendritic Cell Tumors

Tumors of histiocytic or dendritic cell origin appear to occur with increased frequency in patients with lymphoma. Recent molecular data have demonstrated clonal relationships between the lymphoma and the histiocytic/dendritic cell tumor in some of these cases. Clinical, pathologic, and experimental data suggest that this phenomenon probably represents transdifferentiation of the lymphoma clone to a histiocytic/dendritic cell lineage in most cases. Awareness of this entity is necessary to prompt comparative molecular studies in appropriate cases.

Second malignant neoplasms after treatment of childhood acute lymphoblastic leukemia

PURPOSE

Second malignant neoplasms (SMNs) after diagnosis of childhood acute lymphoblastic leukemia (ALL) are rare events.

PATIENTS AND METHODS

We analyzed data on risk factors and outcomes of 642 children with SMNs occurring after treatment for ALL from 18 collaborative study groups between 1980 and 2007.

RESULTS

Acute myeloid leukemia (AML; n = 186), myelodysplastic syndrome (MDS; n = 69), and nonmeningioma brain tumor (n = 116) were the most common types of SMNs and had the poorest outcome (5-year survival rate, 18.1% ± 2.9%, 31.1% ± 6.2%, and 18.3% ± 3.8%, respectively). Five-year survival estimates for AML were 11.2% ± 2.9% for 125 patients diagnosed before 2000 and 34.1% ± 6.3% for 61 patients diagnosed after 2000 (P < .001); 5-year survival estimates for MDS were 17.1% ± 6.4% (n = 36) and 48.2% ± 10.6% (n = 33; P = .005). Allogeneic stem-cell transplantation failed to improve outcome of secondary myeloid malignancies after adjusting for waiting time to transplantation. Five-year survival rates were above 90% for patients with meningioma, Hodgkin lymphoma, thyroid carcinoma, basal cell carcinoma, and parotid gland tumor, and 68.5% ± 6.4% for those with non-Hodgkin lymphoma. Eighty-nine percent of patients with brain tumors had received cranial irradiation. Solid tumors were associated with cyclophosphamide exposure, and myeloid malignancy was associated with topoisomerase II inhibitors and starting doses of methotrexate of at least 25 mg/m(2) per week and mercaptopurine of at least 75 mg/m(2) per day. Myeloid malignancies with monosomy 7/5q- were associated with high hyperdiploid ALL karyotypes, whereas 11q23/MLL-rearranged AML or MDS was associated with ALL harboring translocations of t(9;22), t(4;11), t(1;19), and t(12;21) (P = .03).

CONCLUSION

SMNs, except for brain tumors, AML, and MDS, have outcomes similar to their primary counterparts.

Parvovirus B19-associated hemophagocytic lymphohistiocytosis in a child with precursor B-cell acute lymphoblastic leukemia under maintenance chemotherapy

Development of hemophagocytic lymphohistiocytosis (HLH) is quite rare among acute lymphoblastic leukemia (ALL) patients. We present a 3-year-old boy with precursor B-cell ALL, who was complicated by HLH because of parvovirus B19 infection during maintenance chemotherapy. Remarkable erythroid hypoplasia, giant normoblasts, and hemophagocytosed macrophages in bone marrow were important clues for the diagnosis. The patient was successfully treated with high-dose steroids and intravenous immunoglobulins. To our knowledge, this is the first report describing parvovirus B19-associated HLH in ALL. Our case highlights that parvovirus B19 can cause HLH, a potentially fatal disorder, and prolonged unexpected cytopenia in childhood ALL.

Hemophagocytic lymphohistiocytosis associated with precursor B acute lymphoblastic leukemia

We report a case of a child with precursor-B acute lymphoblastic leukemia (ALL) who experienced refractory thrombocytopenia and massive splenomegaly during standard induction chemotherapy. He was diagnosed with hemophatocytic lymphohistiocytosis (HLH) during induction. Clinical and laboratory evaluation showed no evidence of infectious cause to HLH. Pancytopenia and HLH persisted after consolidation therapy even with remission from leukemia. After failure to control HLH with ALL-directed therapy and HLH-directed therapy, the patient underwent unrelated donor hematopoietic stem cell transplantation 8 months after diagnosis. He is 34 months post-transplant and in remission from leukemia and HLH.

Acute respiratory distress syndrome as an initial presentation of hemophagocytic lymphohistiocytosis after induction therapy for acute myeloid leukemia

A 7-month-old girl with acute myeloid leukemia (AML) developed acute respiratory distress syndrome (ARDS) during the pancytopenic period after induction chemotherapy. Respiratory failure did not improve despite intensive treatments. Eventually, hemophagocytic lymphohistiocytosis (HLH) was diagnosed based on hemophagocytosis in bone marrow, and high soluble interleukin-2 receptor (sIL-2R) and ferritin levels. Even after cyclosporin A was started against HLH, she did not recover. Autopsy showed macrophage proliferation in bone marrow and lymph nodes. HLH should be considered, even in the pancytopenic period after chemotherapy, when patients develop ARDS that does not respond to supportive therapies.

Clinicopathologic features of histiocytic lesions following ALL, with a review of the literature

We describe the clinicopathologic features of 15 patients who had histiocytic lesions that followed acute lymphoblastic leukemia (ALL). Twenty-one separate histiocytic lesions were evaluated that covered a wide spectrum, some conforming to the usual categories of juvenile xanthogranulomas (5), Langerhans' cell histiocytosis (1), Langerhans' cell sarcoma (4), Rosai-Dorfman disease (1), and histiocytic sarcoma (4). Most were atypical for the category by histology, phenotype, or abnormally high turnover rate. Seven low-grade lesions defied easy categorization and were characterized only as "atypical histiocytic lesion" following ALL. For those evaluated, the molecular signature of the prior leukemia was present in the histiocytic lesion. In 3 of 15 patients, the leukemia and histiocytic lesion shared immunoglobulin H or monoclonal TCR gene rearrangements and, in 4 of 15 patients, clonal identity was documented by fluorescence in situ hybridization. Four patients died of progressive disease, 3 of whom had histiocytic sarcoma and 1 who had an atypical lesion. One patient died of recurrent ALL. The other 10 patients are alive, 7 after recurrences and treatment with surgery and/or chemotherapy. The post-ALL lesions are more aggressive than their native counterparts, but despite the demonstration of the presence of the leukemia signature in 7 of 15 patients, the prognosis is generally favorable, except for patients with histiocytic sarcoma. It remains unclear whether the histiocytic lesions arise as a line from the original ALL or whether transdifferentiation is involved.

Rosai-Dorfman disease following bone marrow transplantation for pre-B cell acute lymphoblastic leukemia

A child with acute pre-B cell lymphoblastic leukemia underwent haploidentical bone marrow transplantation (BMT) after first relapse. Approximately 8 months after the BMT, he developed a soft tissue mass overlying a defect in the left frontal bone. He was found to have several additional osteolytic lesions but no evidence of lymphadenopathy or organomegaly. A biopsy of the presenting lesion demonstrated a polymorphous infiltrate composed predominantly of S-100 protein and CD68 immunoreactive histiocytic cells. Together with the presence of emperipolesis, the process was interpreted as Rosai-Dorfman (R-D) disease. He received chemotherapy with vinblastine, prednisone, 6-mercaptopurine and methotrexate and has been in remission for over 4 years. Only one previous example of acute lymphoblastic leukemia in childhood has been reported with R-D disease.

When T cells and macrophages do not talk: the hemophagocytic syndromes

PURPOSE OF REVIEW

Hemophagocytic lymphohistiocytoses represent a rare but biologically and clinically important group of disorders. This review focuses on the clinical, pathophysiologic and genetic manifestations of these disorders along with critical aspects of timely and appropriate treatment.

RECENT FINDINGS

Detailed laboratory investigations have led to significant advances in our understanding of the molecular and pathophysiologic features of hemophagocytic lymphohistiocytoses. These studies have provided new diagnostic tools and potential new therapeutic targets for future development. Parallel to these laboratory studies have been enormous advances in the treatment and improved clinical outcomes of patients with both primary and secondary hemophagocytic lymphohistiocytoses. The eventual merging of the improved understanding of the molecular pathway with novel gene therapy approaches may prove to be the final frontier in the optimal curative treatment of these disorders.

SUMMARY

Several key molecular events have been defined which lead to a final common etiologic pathway of natural killer cell dysfunction leading to the hemophagocytic lymphohistiocytosis syndromes. In part through international clinical trials, effective curative therapies for about half of patients with severe forms of hemophagocytic lymphohistiocytosis have been developed. Although a significant advance, the fact that about 50% of patients are still not able to be cured with currently used approaches challenges physician-scientists to develop more innovative and effective diagnostic and therapeutic approaches.

Precursor B-cell acute lymphoblastic leukemia presenting with hemophagocytic lymphohistiocytosis

Hemophagocytic lymphohistiocytosis (HLH) is a hyperinflammatory syndrome which can be an inherited congenital disorder or can develop secondary to malignancy, infection, or autoimmune disease. Secondary HLH due to malignancy occurs most commonly with T or NK-cell lymphoid neoplasms. HLH with B-cell malignancies is less common and HLH has rarely been described in association with precursor B-cell acute lymphoblastic leukemia (B-ALL). We report three cases of HLH associated with B-ALL and review 17 cases of ALL-associated HLH previously reported in the literature.