Aggressive systemic mastocytosis after germ cell tumor of the ovary: C-KIT mutation documentation in both disease states

A Review of the Clinical Features and Management of Systemic Congenital Mastocytosis through the Presentation of An Unusual Prenatal-Onset Case

Mastocytosis is a heterogeneous group of rare hematological disorders that can occur in infancy. We report a 16-year-old girl who presented with an aggressive form of systemic congenital mastocytosis, associated with a significant global developmental delay, deafness, and multiple anomalies. At 4 years of age, she developed a germinoma presenting as an invasive spinal mass. Extensive cytogenetic, metabolic, and molecular genetic studies that included whole-exome sequencing studies revealed a KIT alteration (NM_000222.3(KIT):c2447A > 7 pAsp816Val) and likely pathogenic variant in the DNA from peripheral blood and skin lesions. C-kit was also found to be overexpressed in the spinal tumor cells. We compared the features of this child to those of six previously reported pediatric patients with cutaneous mastocytosis, microcephaly, microtia, and/or hearing loss reported in OMIM as mastocytosis, conductive hearing loss, and microtia (MIM 248910), for which the etiology has not yet been determined. This report extends the currently recognized spectrum of KIT-related disorders and provides clues as to the potential etiology of a syndromic form of congenital mastocytosis. International efforts to understand the benefits of long-term targeted therapy with tyrosine kinase inhibitors for this KIT-altered rare disease should continue to be evaluated in clinical trials.

Structural equation model based on salutogenesis theory for evaluating factors affecting health-related quality of life in adolescents with moyamoya disease

Moyamoya disease is a cerebrovascular disorder and a significant chronic health concern requiring regular monitoring to control the disease and its related complications. We examined a hypothetical model by integrating the concepts of a structural health-related quality-of-life model based on the salutogenesis theory, and to identify how social support, sense of coherence, and stress contribute to health behaviors, subjective health status, and quality of life in adolescents with moyamoya disease among 239 adolescents in Korea. A structural equation model was used to analyze the data. The fitness of the hypothetical model with the salutogenesis theory was satisfactory, showing that the goodness-of-fit index = 0.91, adjusted goodness-to-fit index = 0.90, comparative fit index = 0.92, normed fit index = 0.91, incremental fit index = 0.91, standardized root mean squared residual = 0.04, root mean square error of approximation = 0.07, parsimony normed fit index = 0.61, parsimony goodness of fit index = 0.51. The model explained 68.9% of quality of life. Health behavior (β = -0.173, p = 0.467) and stress (β = -0.557, p < 0.001) had significant direct and total effects on quality of life. Sense of coherence had a significant direct (β = 0.371, p = 0.003), indirect (β = 0.220, p = 0.013), and total (β = 0.590, p < 0.001) effect on quality of life. This study found that sense of coherence was significant factors contributing to lower stress, improved health status, and quality of life in adolescents with moyamoya disease. To improve the quality of life for adolescents with moyamoya disease, comprehensive nursing interventions need to be developed and applied.

Mast cell sarcoma: clinicopathologic and molecular analysis of 10 new cases and review of literature

Mast cell sarcoma (MCS) is an exceedingly rare form of mastocytosis characterized by invasive malignant mast cell growth and metastatic potential. Diagnosis of MCS is very challenging due to its marked morphologic variations and significant immunophenotypic overlap with other neoplasms. In this study, we undertook an extensive study of 10 cases of MCS from our series, with review of additional 24 cases from the literature, to better clarify the clinicopathologic and molecular features of MCS. From the analyses of our 10 cases, MCS equally involved males and females with a median age of 54.5 years (range 1-63). The bone was the most common site of involvement, as noted in 9/10 of cases. Two patients had prior germ cell tumors (mediastinal germ cell tumor and ovarian dysgerminoma), and concurrent systemic mastocytosis was noted in one of nine patients. Serum tryptase levels were elevated in 6/7 of patients, and 3/9 of patients had mast cell activation symptoms. Morphologically, the tumor cells were typically large and pleomorphic with frequent reactive eosinophils. By immunohistochemical staining, MCS consistently expressed CD43 (8/8), CD117 (10/10), and mast cell tryptase (10/10), as well as CD13 (3/3) and CD33 (10/10), with variable positivity of CD2 (1/9), CD25 (4/9), CD30 (5/8), and CD68 (5/9). Notably, KIT D816V was not detected in nine cases in our study, although two cases had other mutations of KIT gene. Seven out of eight patients received chemotherapy with or without radiotherapy. However, the response was poor, and four out of eight patients died within a median follow-up interval of five months. Taken together, there are no standardized therapeutic regimens available for MCS at this time, and the prognosis is dismal. Therefore, it is critical to further investigate and characterize this rare entity, with the hope of improving diagnostic accuracy and providing more effective, targeted therapies.

Ovarian germ cell tumor/mastocytosis with KIT mutation: A unique clinicopathological entity

Most tumors are sporadic and originated from somatic mutations. Some rare germline mutations cause familial tumors, often involving multiple tissues or organs. Tumors from somatic mosaicism during embryonic development are extremely rare. We describe here a pediatric patient who developed both an ovarian germ cell tumor and systemic mastocytosis. Targeted DNA next-generation sequencing analysis revealed similar genomic changes including the same KIT D816V mutation in both tissues, suggesting a common progenitor cancer cell. The KIT mutated cells are likely from early embryonic development during germ cell migration. A literature search found additional eight similar cases. These diseases are characterized by pediatric-onset, all-female, neoplastic proliferation in both gonad and bone marrow, and a common oncogenic cause, that is, KIT mutation, constituting a clinically and genetically homogenous disease entity. Importantly, the association of germ cell tumors with hematopoietic neoplasms suggests that the primordial germ cells are the primitive hematopoietic stem cells, a much-debated and unsettled question.

An aggressive systemic mastocytosis preceded by ovarian dysgerminoma

BACKGROUND

Aggressive systemic mastocytosis (ASM) is a rare malignant disease characterized by disordered mast cell accumulation in various organs. We here describe a female ASM patient with a previous history of ovarian dysgerminoma.

METHODS

Molecular cytogenomic analyses were performed to elucidate an etiological link between the ASM and dysgerminoma of the patient.

RESULTS

This patient was affected by ovarian dysgerminoma which was treated by chemotherapy and surgical resection. Having subsequently been in complete remission for 2 years, she developed symptoms of ASM. A somatic D816A mutation in the KIT gene was detected in her bone marrow, which facilitated the diagnosis of ASM. Unexpectedly, this KIT D816A variant was also detected in the prior ovarian dysgerminoma sample. Whole-exome sequencing allowed us to identify a somatic nonsense mutation of the TP53 gene in the bone marrow, but not in the dysgerminoma. Microarray analysis of the patient's bone marrow revealed a copy-number-neutral loss of heterozygosity at the TP53 locus, suggestive of the homozygous nonsense mutation in the TP53 gene. In addition, the loss of heterozygosity at the TP53 locus was also detected in the dysgerminoma.

CONCLUSIONS

These results indicated that either the mast cells causing the ASM in this case had originated from the preceding ovarian dysgerminoma as a clonal evolution of a residual tumor cell, which acquired the TP53 mutation, or that both tumors developed from a common cancer stem cell carrying the KIT D816A variation.

Mastocytosis in Children

PURPOSE OF REVIEW

In this review, we examine the current understanding of the pathogenesis, clinical presentations, diagnostic tools, and treatment options of pediatric mastocytosis as well as the natural history of the disease.

RECENT FINDINGS

We discuss the emerging concept of mast cell activation syndrome. Mastocytosis in children presents most commonly as isolated cutaneous lesions and is a relatively rare occurrence with excellent prognosis and spontaneous regression often occurring by adolescence. Systemic mastocytosis with organ system involvement is a more serious condition and is likely to persist into adulthood.

Abnormal bone marrow histopathology in paediatric mastocytosis

The diagnostic criteria for paediatric mastocytosis are largely based on adult studies and bone marrow findings are not well described in children. We evaluated use of the World Health Organization (WHO) criteria for the diagnosis of systemic disease in paediatric mastocytosis. In addition, we identified unique clinico-histopathological features within the biopsies. One hundred and thirteen children with paediatric mastocytosis were evaluated at the National Institutes of Health between 1986 and 2013. Complete bone marrow evaluations were performed in 50 cases. Seven children had repeat procedures. Bone marrows were analysed by histopathology, flow cytometry and for KIT D816V. Bone marrow biopsies displayed mild atypical haematopoietic maturation, increased haematogones and hypocellularity in a sub-set of patients with urticaria pigmentosa, diffuse cutaneous mastocytosis and indolent systemic mastocytosis. Hypocellularity was most pronounced in those with urticaria pigmentosa. Haematogones were highest, on average, in patients with diffuse cutaneous mastocytosis or mastocytomas. There was no evidence of peripheral blood cytopenias, myelodysplastic syndrome, myeloproliferative neoplasm or leukaemia within this cohort. The WHO criteria are applicable for the diagnosis of systemic mastocytosis in paediatrics. Although unsuspected bone marrow findings typically seen in myeloproliferative disorders are frequent in paediatric mastocytosis, patients within this study remained clinically stable without progression to a more aggressive variant.

Mastocytosis

Mastocytosis is a disorder of abnormal mast cell proliferation, with clinical features that include flushing, pruritus, abdominal pain, diarrhea, hypotension, syncope, and musculoskeletal pain. These features are the result of mast cell mediator release and infiltration into target organs. Patients of all ages may be affected, although in children, manifestations primarily involve the skin. Most patients with systemic disease have a somatically acquired activating mutation in the KIT oncogene. This article discusses the causes and pathogenesis of mastocytosis, with an overview of the clinical features and the approach to diagnosis, evaluation, and therapy in adults and pediatric patients.

Synchronous development of KIT positive acute myeloid leukemia in a patient with gastrointestinal stromal tumor

We report a case of synchronous occurrence of KIT-positive acute myeloid leukemia (AML) and gastrointestinal stromal tumor (GIST). A 63-year-old woman was hospitalized for dizziness, and abdominal computed tomography revealed an exophytic gastric mass and hepatic metastasis. The patient was diagnosed with GIST and was administered imatinib (400 mg/day) for the metastatic unresectable tumor. After 2 weeks of imatinib treatment, the patient developed pancytopenia, which persisted even after the drug was discontinued, thereby necessitating bone marrow biopsy. Biopsy examination indicated AML, and karyotyping revealed a complex karyotype. We did not observe point mutations at residues D816 and N822 of KIT. Therefore, the patient received standard induction chemotherapy, but on the 18^th day after completion of chemotherapy, she died of septic shock and multi-organ failure. Since KIT plays an important role in both GIST and AML, we consider that both these malignancies may have been associated with each other.