The role of mutant IDH1 and IDH2 inhibitors in the treatment of acute myeloid leukemia.

For decades, researchers have looked into the pathophysiology of acute myeloid leukemia (AML). With the advances in molecular techniques, the two-hit hypothesis was replaced by a multi-hit model, which also emphasizes the importance of aberrant epigenetic regulation in the pathogenesis of AML. IDH1 and IDH2 are two isoforms of isocitrate dehydrogenase that perform crucial roles in cellular metabolism. Somatic mutations in either of these two genes impart a neomorphic enzymatic activity upon the encoded enzymes resulting in the ability to convert α-ketoglutarate (αKG) into the oncometabolite R2-hydroxyglutarate (R2-HG), which can competitively inhibit multiple αKG-dependent dioxygenases. Inhibition of various classes of αKG-dependent dioxygenases results in dramatic epigenetic changes in hematopoietic cells, which has been found to directly impair differentiation. In addition to a global dysregulation of gene expression, other mechanisms have been described through which R2-HG promotes leukemic transformation including the induction of B cell lymphoma 2 dependency and stimulation of the EglN family of prolyl 4-hydroxylases (EglN). Due to the fact that mutations in IDH1 and IDH2 are acquired early during AML clonal evolution as well as because these mutations tend to remain stable during AML progression, the pharmaceutical industry has prompted the development of specific mutant IDH enzyme inhibitors. More recently, the FDA approved the first mutant IDH2 inhibitor, enasidenib (AG-221), for patients with relapsed or refractory IDH2-mutated AML (RR-AML). This has brought a lot of excitement to researchers, clinicians, and patients, especially because the treatment of AML remains challenging and is still associated with a high mortality.

PD-1 signaling and inhibition in AML and MDS.

Acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) are clinically and molecularly heterogeneous clonal myeloid disorders with a poor prognosis especially in the relapsed refractory setting and in patients above the age of 60. While allogeneic hematopoietic stem cell transplantation (ASCT) is a potentially curative approach, high relapse, morbidity, and mortality rates necessitate the development of alternative therapies. Immune checkpoint inhibitors unmask tumoral immune tolerance and have demonstrated efficacy in the treatment of chemotherapy-resistant hematologic and solid malignancies. The rationale for the investigation of those agents in AML and MDS is supported by an observed increased expression of programmed cell death 1 protein (PD-1) and ligand 1 (PD-L1) in the hematopoietic microenvironment of AML and MDS, and its association with low TP53 and a poor prognosis. Early clinical experience in combination with a hypomethylating agent has shown encouraging responses; however, larger clinical trials are needed to determine the role of checkpoint inhibition in myeloid malignancies.

Herpes simplex virus encephalitis during treatment with etanercept.

Tumor necrosis factor alpha (TNF-α) inhibitors are widely used for the treatment of various inflammatory conditions. They are associated with an increased risk for infections. We report a case of herpes simplex virus type 1 (HSV-1) encephalitis in a patient receiving etanercept and review the literature on TNF-α and TNF-α inhibitors, and their importance in the pathophysiology of herpes simplex encephalitis.

Integrating Immunotherapy into Multimodal Treatment of Head and Neck Cancer.

Patients with locally advanced head and neck squamous cell carcinoma (HNSCC) have a poor prognosis, with a significant risk of progression or death despite multimodal treatment with surgery, chemotherapy, and radiotherapy. Immune checkpoint inhibitors targeting the programmed death receptor-1 (PD1) have dramatically changed the treatment landscape for recurrent/metastatic disease, improving overall survival in both the first- and second-line palliative settings. This success has driven the investigation of treatment strategies incorporating immunotherapy earlier into the multimodal curative-intent or salvage treatment of both locally advanced and recurrent/metastatic HNSCC. This review encompassed the following three subjects, with a focus on recently reported and ongoing clinical trials: (1) the use of neoadjuvant immunotherapy prior to surgery for locally advanced HNSCC, (2) the use of immunochemoradiotherapy for locally advanced head and neck cancers, and (3) novel uses of immunotherapy in the salvage of recurrent/metastatic HNSCC via a combined modality, including reirradiation paradigms. The results of these studies are eagerly awaited to improve patient outcomes in this challenging disease.

Intensified Adjuvant Treatment for High-Risk Resected Cutaneous Angiosarcoma of the Head and Neck.

OBJECTIVE: Previous studies have highlighted the poor survival of patients with cutaneous angiosarcoma of the head and neck. Therapeutic options are limited, and effective treatment strategies are yet to be discovered. The objective of this study is to evaluate overall survival following intensified adjuvant treatment for high-risk resected angiosarcoma of the head and neck. STUDY DESIGN: Retrospective observational. SETTING: National Cancer Database (NCDB). METHODS: Patients diagnosed with nonmetastatic cutaneous angiosarcoma of the head and neck from 2004 to 2016 were identified by NCDB. We retrospectively compared demographics and overall survival between patients who received surgery and radiation therapy (SR) and patients who received surgery and chemoradiation (SRC). The χ2 test, Kaplan-Meier method, and Cox regression models were used to analyze data. RESULTS: A total of 249 patients were identified, of which 79.5% were treated with surgery and radiation alone and 20.5% were treated with surgery and chemoradiation. The addition of chemotherapy, regardless of the sequence of administration, was not associated with significantly higher overall survival. Factors associated with worse survival in both groups included positive nodal status and positive margins. Patients with positive nodes had higher overall survival with radiation doses >50.4 Gy compared to ≤50.4 Gy (hazard ratio: 2.93, confidence interval: 1.60-5.36, p < 0.001). CONCLUSION: Adjuvant chemotherapy was not significantly associated with higher overall survival for resected nonmetastatic angiosarcoma of the head and neck. Higher radiation doses appear to be prognostic for high-risk diseases.

Filgrastim induced thrombocytopenia.

Drug-induced thrombocytopenia (DITP) is suggested by severe thrombocytopenia with subsequent recovery of platelet count after removal of the offending drug. The diagnosis is ascertained when there is reproducibility of thrombocytopenia with repeated exposure. Filgrastim is used during peripheral blood progenitor cell harvest during autologous stem cell transplantation in the setting of multiple myeloma to prolong event-free survival and overall mortality. The following case illustrates all of the suggestive features of DITP after filgrastim exposure during elective stem cell harvest. Due to the inability to tolerate filgrastim, autologous stem cell transplant was aborted in this patient and he was maintained on induction chemotherapy.

Novel Immunotherapeutic Agents for the Treatment of Multiple Myeloma.

Multiple myeloma (MM) is a B-cell malignancy characterized by the abnormal proliferation of clonal plasma cells in the bone marrow leading to end-organ manifestations. Despite the advancement in the therapy and care of patients with MM, relapse and resistance to standard therapy remain significant. The development of immunotherapy as a treatment modality for many types of cancers has led investigators to explore its use in MM in order to elicit myeloma-targeted immune responses, especially given that immune dysregulation is an underlying feature in the pathogenesis and progression of MM. In this concise review, we discuss the different advances in the immune-based therapy of MM, from immunomodulation, vaccines, to monoclonal antibodies, checkpoint inhibitors, adoptive T-cell therapies, and future promising therapies under investigation.

An atypical presentation of Sweet's syndrome in a myelofibrosis patient.

A 46-year-old man with no significant medical history presented to haematology with symptoms of fatigue, dyspnoea on exertion and weight loss. Physical examination revealed a lesion on the right shin and splenomegaly. Labs were significant for leucocytosis with immature components, thrombocytosis and 3% peripheral blasts on smear. A bone marrow biopsy confirmed a diagnosis of myelofibrosis (MF). Dynamic International Prognosis Scoring system was 2. He was started on ruxolitnib, with decitabine added subsequently prior to definitive therapy with an allogenic haematopoietic stem cell transplant. His course with decitabine was complicated with febrile neutropaenia with multiple tender erythematous plaques unresponsive to antibacterial and antifungal coverage. A skin biopsy showed neutrophilic dermatitis, consistent with a diagnosis of Sweet's syndrome (SS) and empirical treatment with glucocorticoids was initiated resulting in resolution of symptoms. This report reviews the literature for cases of SS in the setting of MF.

Two distinct histological Richter's transformations 23 years apart in a patient with chronic lymphocytic leukaemia.

A 53-year-old man with a 1-year history of chronic lymphocytic leukaemia (CLL) presented with a left bicep mass. Biopsy and staging workup revealed Richter's transformation (RT) Ann Arbor stage 1E diffuse large B-cell lymphoma in the bicep. The patient was treated with combination chemotherapy with cyclophosphamide, doxorubicin, Vincristine and prednisone followed by site radiation and did well thereafter. His CLL progressed and required treatment on two more occasions 11 and 18 years after his initial diagnosis with fludarabine, Cytoxan and Rituxan and then with bendamustine and rituximab. 23 years after initial presentation, he developed diffuse lymphadenopathy and B-symptoms. A biopsy of an enlarged cervical lymph node demonstrated only CLL for which he was started on ibrutinib. Treatment was shortly discontinued thereafter due to intolerance and worsening symptoms. A second biopsy was performed which revealed concurrent CLL and Hodgkin's lymphoma representing a second and histologically distinct RT.

Erdheim-Chester Disease: Comprehensive Review of Molecular Profiling and Therapeutic Advances.

The revised 2016 World Health Organization classification introduced Erdheim-Chester disease (ECD) as a provisional entity within the histiocytic and dendritic cell neoplasms separate from the juvenile xanthogranuloma family based on distinct molecular features. However, evolving knowledge regarding the molecular and genetic aberrations in addition to common clinical features of ECD support the classification of ECD together with Langerhans cell histiocytosis (LCH). Accordingly, ECD can be thought of as an inflammatory myeloid clonal disorder based on the detection of various activating mutations along the mitogen activated protein kinase-extracellular signal regulated kinase (MAPK-ERK) pathway with most notable variant being a valine to a glutamic acid substitution at amino acid 600 in the B-rapidly accelerated fibrosarcoma protein (BRAFV600E). In this group, targeted therapy with a B-Raf inhibitor alone or combined with a MAPK-ERK (MEK) inhibitor has shown promising results based on several case reports. Currently, two phase II trials with BRAF inhibitors are underway and could potentially change the standard of care. MEK inhibitors may also be efficacious in ECD harboring mutations in MAP2K1; other potential targetable aberrations include programed cell death receptor 1 and mutations in phosphoinositide 3-kinase.

Extramedullary haematopoiesis presenting with cardiac tamponade in a patient with polycythaemia vera.

A 71-year-old man with a history of polycythaemia vera, diagnosed 4 years ago, presented to the emergency room with shortness of breath. A bedside echocardiogram revealed a large pericardial effusion with features concerning for pericardial tamponade. A left anterior thoracotomy and a pericardial window were emergently performed in the operating room and relieved the patient's symptoms. Histology evaluation of the pericardial fragments and pericardial fluid revealed the presence of trilineage haematopoietic elements without any increase in the blasts. A bone marrow core biopsy revealed an increase in reticulin fibre and increase in the number of blasts of 5%-10%, whereas peripheral blood testing was positive for JAK2 V617F mutation. This case report reviews the literature for cases of extramedullary haematopoiesis associated with myeloproliferative neoplasms.

Anaemia with inflammation responding to lenalidomide.

We present a case of a 73-year-old woman with transfusion-dependent anaemia thought to be secondary to an unidentifiable inflammatory condition. Anaemia evaluation including multiple bone marrow biopsies was unrevealing, with the exception of a non-specific elevation of her erythrocyte sedimentation rate and C-reactive protein. She had no identifiable inflammatory condition and did not meet the criteria for myelodysplastic syndrome. She was empirically treated with lenalidomide and achieved a complete response, suggesting that this immunomodulatory drug could potentially have a role in treating a subgroup of patients with immune-mediated anaemia.