Erdheim-Chester Disease with BRAF V600E Mutation and a Concomitant Myeloid Malignancy Sharing NRAS and IDH2 Mutations.

Erdheim-Chester disease (ECD) is a rare clonal histiocytic process that is characterized by a foamy (xanthomatous) proliferation often associated with Touton giant cells. The diagnosis is often challenging and not exclusively a histologic diagnosis, as it requires correlation with unique clinical, radiographic, and recently described molecular findings. Activating mutations involving the MAPK pathway including BRAF, ARAF, N/KRAS, and MEK are recurrent in the disease. However, it is increasingly being described that mutations associated with clonal hematopoiesis are also found in bone marrow specimens of patients with ECD, as well as higher frequency of overt concomitant myeloid malignancy including acute myeloid leukemia, myeloproliferative neoplasms, myelodysplastic syndromes, and mixed myeloproliferative neoplasms/myelodysplastic syndromes. Herein, we report a unique case of a patient presenting with BRAFV600E-positive ECD with peripheral blood findings consistent with a concurrent myeloid malignancy featuring co-occurrence of NRAS and IDH2 mutations.

Intravascular Large B Cell Lymphoma of the Breast: A Rare Entity.

Intravascular large B-cell lymphoma (IVLBCL) is a rare and high-grade disease of neoplastic lymphoid cells within the vascular lumina of small- to medium-sized vessels. The disease carries a grim prognosis despite robust treatment protocols. We discuss the case of a 58-year-old female who presented with mammographic screening abnormality which led to more investigations and ultimately to this diagnosis. The patient had no prior history of a lymphoma or in situ and invasive carcinoma of the breast. To our knowledge, IVLBCL of the breast is a very rare and an unusual location for this type of a lymphoma and so far, only five reported cases. Through our case report, we not only discuss the case but also review literature on this rare entity.

The utility of thromboelastography and tranexamic acid in plasminogen activator inhibitor deficiency during pregnancy: a rare case report.

: Complete plasminogen activator inhibitor-1 (PAI-1) deficiency is a very rare genetic disorder that is associated with an increased risk of bleeding diathesis. Patients with PAI-1 deficiency are also known to be at increased risk for massive postpartum hemorrhage. We discuss one such rare case of PAI-1 deficiency in a young pregnant patient at 22 weeks of gestation with history of prolonged bleeding. Tranexamic acid was administered for menorrhagia and resumed later for labor and continued into the postpartum period since antifibrinolytics have been the mainstay in the management of PAI-1 deficiency. The patient delivered a healthy infant at 39 weeks. As PAI-1 deficiency causes increased fibrinolysis, the patient's coagulation panel was monitored by performing serial thromboelastograms to monitor for any increase in fibrinolysis. We believe that thromboelastograms might be a useful tool in the monitoring and management of fibrinolytic conditions such as PAI-1 deficiency.

Extraneural Metastasis of Primary Glioma Occurring in a Setting of Occupational Ionizing Radiation Exposure.

Malignant gliomas account for 60% of all primary brain tumors in adults. Glioblastoma Multiforme (GBM) is the most common primary glial tumor with a dismal prognosis and a median survival of approximately 14 months. Extra-neural metastases from primary brain tumors are unusual with an incidence rate of less than 2%. This has been attributed to factors such as short survival, lack of true lymphatics in the CNS, and physical barriers provided by the dura, extracellular matrix, and basement membrane. Although most GBMs occur sporadically, there is a known association with therapeutic radiation exposure and with work in nuclear disaster cleanup. To our knowledge, no case of GBM with metastasis occurring in a patient with occupational radiation exposure currently exists in the literature. In this article, we present a case of GBM with lung metastasis occurring in a 51-year-old Caucasian male, whose history is significant for occupational exposure to ionizing radiation, and review the literature on GBM risk factors and potential mechanisms of metastasis.

Cell block cellularity: A comparison of two fixatives and their impact on cellularity.

BACKGROUND: Ancillary testing including immunohistochemistry and molecular diagnostics has become an increasingly important component for the evaluation of cytologic specimens. Ancillary testing is important not only for diagnosis but also for predictive and prognostic evaluation. While a number of substrates are appropriate for ancillary testing, cell block specimens are commonly utilized and the success of ancillary testing depends on cell-block cellularity. METHODS: Forty-six pairs of cases each fixed in both formalin and CytoLyt were each analyzed by two evaluators for overall cellularity. Linear regression was used to assess inter-rater reliability of cell counts for each method. Cellularity scores for each case were obtained by averaging the scores for each rater and cellularity was compared between the methods. RESULTS: Inter-rater agreement was very good for both methods. The coefficient of determination was 1.0 and 0.99 for the CytoLyt and formalin methods respectively. Cell blocks using the CytoLyt method have lower levels of cellularity than cell blocks performed by the formalin method. CONCLUSIONS: Cell blocks prepared using a formalin fixative yield significantly greater cellularity than those produced by the CytoLyt method. Formalin fixation appears to optimize cellularity of cell blocks useful for ancillary testing.

Novel TLE4-NTRK2 fusion in a ganglioglioma identified by array-CGH and confirmed by NGS: Potential for a gene targeted therapy.

Gangliogliomas are rare neoplasms of the central nervous system that mostly originate in the temporal lobe and are associated with seizures. Literature mentions that BRAF mutations are most commonly associated with gangliogliomas. We discuss a unique case of ganglioglioma originating in the posterior fossa that showed multiple losses and a unique interstitial deletion at 9q21 by an array-comparative genome hybridization (array-CGH). The deletion led to a novel molecular fusion (TLE4-NTRK2) which was confirmed by next generation sequencing and provides a potential for a gene-targeted therapy.