Evidence of clonality in cases of hypereosinophilia of undetermined significance

Clinical Management of Persistent Hypereosinophilia

Blood eosinophilia remains a common finding in the general population, whereas hypereosinophilia (HE) is extremely rare. Different non-hematologic and hematologic disorders may be accompanied by blood eosinophilia. Clinical manifestations of eosinophilia-related disorders range from mild to life-threatening. Given the various symptoms, a comprehensive approach and close multidisciplinary cooperation are strongly recommended. Hypereosinophilic syndromes (HES) encompass a complex group of disorders defined as persistent peripheral blood HE ≥ 1500/mm3 and end-organ damage. An initial step in a diagnostic algorithm of HE includes the evaluation of secondary, potentially easy-to-treat causes. This HES variant is called reactive and often remains beyond the interest of hematologists. The further evaluation for primary causes of HE relies on a combination of different specialized tests, which are mostly available in hematologic centers and include most of all morphologic assessments of peripheral blood and bone marrow, cytogenetics, and molecular studies. Using these sophisticated methods, one can diagnose the specific HES subtypes based on genetic findings and categorize them according to currently applicable classifications. The choice of therapy differs between HES variants, ranging from corticosteroids and anti-interleukin-5 monoclonal antibodies for not-molecularly defined variants to oral molecules directed against molecular targets. This review presents eosinophilia-related disorders from a hematologic perspective.

Chronic eosinophilic leukaemia-Not otherwise specified: Clinical features, genomic insight and therapeutic strategies

Chronic eosinophilia leukaemia-not otherwise specified (CEL-NOS) is a rare myeloproliferative neoplasm characterized by persistent clonal hypereosinophilia. Recent advances in genetics have refined diagnostic criteria, leading to the identification of CEL subtypes with specific cytogenetic and molecular abnormalities now classified as myeloid/lymphoid neoplasms with eosinophilia and tyrosine kinase gene fusions, which may benefit from targeted therapies. In contrast, CEL-NOS lacks specific genetic drivers and intervention points to halt leukemogenesis. Molecular techniques have also enabled the definition of clonality in a considerable percentage of cases otherwise classified as idiopathic hypereosinophilic syndrome. CEL-NOS poses a significant therapeutic challenge due to limited treatment options, poor prognosis and the risk of progression to acute leukaemia. Patients, often elderly and with comorbidities, face restricted access to transplantation, the only potentially curative treatment. Unfortunately, the prognosis remains poor even post-transplant, with a 5-year survival rate of only one-third of patients. Other therapies, including steroids, cytoreductive and immunomodulatory treatments, offer limited and temporary responses with significant side effects. This review aims to consolidate current knowledge on CEL-NOS, covering diagnostic approaches, genetic advancements and therapeutic challenges. It seeks to provide a comprehensive overview and highlight critical areas for future research.

Early Bereavement Psychosocial Outcomes in Parents of Children Who Died of Cancer With a Focus on Social Functioning

PURPOSE

The early grief experience of parents of children who died of cancer remains understudied. Understanding psychosocial symptomology and functioning of parents early in their bereavement is essential to developing supportive interventions aimed at offsetting poor mental and physical outcomes.

METHODS

Parents of children from two centers who died of cancer 6 to 24 months before were mailed a survey that included validated tools and additional Likert scale-based questions. We used correlation and univariate and multiple regression analyses to assess the associations between psychosocial and grief outcomes and parental social functioning.

RESULTS

One hundred twenty-five parents representing 88 children completed the survey. Most respondents identified as female (63%), White (84%), and non-Hispanic (91%). The mean time since child's death was 14.7 (range, 8-26) months. Bereaved parents' mean score for social functioning was only slightly below normative values, and most parents indicated post-traumatic growth and adaptive coping. Parents had high symptom levels for depression, anxiety, post-traumatic stress, and prolonged grief, with those identifying as female having significantly higher symptom scores. Using multivariate analysis, parental scores for resilience and continuing bonds were associated with higher social functioning scores and parental scores for depressive symptoms and prolonged grief were associated with lower social functioning scores.

CONCLUSION

Although bereaved parents exhibit resilience and positive coping, they also show high levels of psychosocial distress in the first 2 years after their child's death, which may reflect the typical parental bereavement experience. Screening for low parental social functioning may identify parents who would benefit from additional support early in bereavement.

Clinical Significance of Clonal Hematopoiesis of Indeterminate Potential in Hematology and Cardiovascular Disease

Liquid profiling uses circulating tumor DNA (ctDNA) for minimal invasive tumor mutational profiling from peripheral blood. The presence of somatic mutations in peripheral blood cells without further evidence of a hematologic neoplasm defines clonal hematopoiesis of indeterminate potential (CHIP). CHIP-mutations can be found in the cell-free DNA (cfDNA) of plasma, are a potential cause of false positive results in liquid profiling, and thus limit its usage in screening settings. Various strategies are in place to mitigate the effect of CHIP on the performance of ctDNA assays, but the detection of CHIP also represents a clinically significant incidental finding. The sequelae of CHIP comprise the risk of progression to a hematologic neoplasm including therapy-related myeloid neoplasms. While the hematological risk increases with the co-occurrence of unexplained blood count abnormalities, a number of non-hematologic diseases have independently been associated with CHIP. In particular, CHIP represents a major risk factor for cardiovascular disease such as atherosclerosis or heart failure. The management of CHIP requires an interdisciplinary setting and represents a new topic in the field of cardio-oncology. In the future, the information on CHIP may be taken into account for personalized therapy of cancer patients.

Chronic Eosinophilic Leukaemia Associated with JAK2 Exon 13 Insertion/Deletion Mutations

Chronic eosinophilic leukaemia, not otherwise specified (CEL, NOS), is a diagnosis of exclusion made in cases in which there is clonal eosinophilia but an absence of genetic aberrations that define other disease subtypes. There is a need for further characterization of these cases in order to inform risk stratification and management. The importance of JAK2 mutations in myeloproliferative neoplasms (MPN) as a whole is well established, although their role specifically in eosinophilic disorders is less clear, with only a minority of cases demonstrating JAK2 abnormalities. Here, we report 2 cases with an exon 13 insertion-deletion (indel) mutation in JAK2: one with CEL-NOS and the second with an unspecified eosinophilic disorder. JAK2 indels were not detected in a screen of suspected MPN cases (n = 592) without eosinophilia that tested negative for common MPN driver mutations. Our findings thus provide further evidence for a specific association between this rare mutation and clonal eosinophilic disorders.

Hypereosinophilic syndromes - An enigmatic group of disorders with an intriguing clinical spectrum and challenging treatment

Hypereosinophilic syndromes (HES) comprises a group of rare disorders characterized by blood hypereosinophilia (>1.5 × 10⁹/l) accompanied by eosinophil-associated organ damage. The 2016 World Health Organization classification recognizes a category of myeloid/lymphoid neoplasms with prominent eosinophilia (M/L_eo) and well-characterized gene rearrangements of PDGFRA/B, FGFR1 or JAK2. PDGFRA/B-rearranged patients usually manifest as imatinib-sensitive myeloproliferative neoplasms (MPNs). FGFR1- and JAK2- rearranged cases may manifest as MPNs or aggressive lymphomas/leukemias and historically have had a dismal prognosis, although clinical trials with targeted treatment are promising. A negative screen for M/L_eo in a patient with myeloid features should prompt consideration of a diagnosis of chronic eosinophilic leukemia-not otherwise specified. If these are excluded and a secondary cause is not identified, a diagnosis of idiopathic HES and/or other rare variants of HES should be considered. This review, through an illustrative case, summarizes current knowledge on HES pointing at new directions in diagnosis and treatment.