In Situ Follicular B-Cell Neoplasm Presenting as Miliary Facial Papules: A Unique Clinical Presentation and Spontaneous Regression.

In situ follicular B-cell neoplasm (ISFN) is a variant of follicular lymphoma, presenting as an incidental histologic finding in lymph node biopsy or excisional specimens. ISFN presents with a B-cell population that strongly expresses BCL2 and CD10 within the germinal centers of a lymph node or extranodal site. Genetic analysis shows t(14;18) translocation.

Deep immunophenotypic analysis of the bone marrow progenitor cells in myelodysplastic syndromes.

Background: Diagnosis of myelodysplastic syndromes (MDS) is often challenging and requires integration of clinical, morphologic, cytogenetics and molecular information. Flow cytometry immunophenotyping (FCIP) can support the diagnosis by demonstration of numerical and immunophenotypic abnormalities of progenitor and maturing myelomonocytic and erythroid populations. We have previously shown that comprehensive immunophenotypic analysis of the progenitor population is valuable in the diagnosis of MDS and myelodysplastic/myeloproliferative neoplasms (MDS/MPN).

Primary Follicular Dendritic Cell Sarcoma of Urinary Bladder.

Follicular dendritic cell sarcoma is a rare malignant mesenchymal neoplasm composed of follicular dendritic cells. A subset of cases can be found at extranodal sites. Only 2 follicular dendritic cell sarcomas were previously reported in the urinary bladder.

Exploring blast composition in myelodysplastic syndromes and myelodysplastic/myeloproliferative neoplasms: CD45RA and CD371 improve diagnostic value of flow cytometry through assessment of myeloblast heterogeneity and stem cell aberrancy.

Background: Flow cytometry immunophenotyping (FCIP) can improve diagnosis of myelodysplastic syndromes (MDS) and myelodysplastic/myeloproliferative neoplasms (MDS/MPN), although its application is challenging due to difficulties in standardization, complexity of antibody panels and subjective interpretation of data. Since blasts are invariably affected in these disorders, we developed a FCIP approach for detailed and objective analysis of the blast population.

Methods: FCIP using a one-tube 10-color (13-marker) antibody panel was performed on bone marrow samples from 23 MDS and 8 MDS/MPN patients, 21 cytopenic patients non-diagnostic for MDS (Non-MDS), and 16 Control samples.

Cerebrospinal Fluid Flow Cytometry: Utility in Central Nervous System Lymphoma Diagnosis.

Background: Flow cytometry of the cerebrospinal fluid (CSF) is used in isolation or as an adjunct to cytology to increase the sensitivity of detecting central nervous system (CNS) lymphoma. We aimed to evaluate the sensitivity of CSF flow cytometry as a diagnostic screening tool for primary CNS lymphoma in patients presenting with undifferentiated neurologic symptoms.

Methods: We retrospectively reviewed all CSF samples received by the Calgary Laboratory Services Flow Cytometry Laboratory from 2012 to 2015.

Epstein-Barr virus-associated inflammatory pseudotumor presenting as a colonic mass.

Epstein-Barr virus (EBV)-positive inflammatory pseudotumor (IPT) commonly involves spleen and liver and has only rarely been reported in the gastrointestinal (GI) tract. The spindle cells may express myofibroblastic or follicular dendritic cell markers. We report a challenging case of EBV-positive IPT arising in the ascending colon.

Multiple lymphomatous diverticulosis and comorbid chronic lymphocytic leukemia: novel manifestations of ileocolic mantle cell lymphoma.

Mantle cell lymphoma (MCL) has tropism for the gastrointestinal tract (GIT) identifiable as multiple polyps and mass lesions throughout the GIT. We describe 2 novel manifestations of MCL. A 60-year-old woman with known chronic lymphocytic leukemia (CLL) had an exophytic mass of the appendiceal orifice.

Cyclin D1 and t(11;14)-positive B-cell neoplasms resembling marginal zone B-cell lymphoma: a morphological variant of mantle cell lymphoma.

We describe 3 unusual B-cell non-Hodgkin's lymphomas in which the entire tumors histologically mimicked marginal zone B-cell lymphoma. All patients were male (mean age, 65 years). Excisional biopsy from lymph node (2 of 3) and parotid gland (1 of 3) showed proliferation of monocytoid B-cells with plasmacytoid features (2 of 3) and conspicuous absence of large lymphoma cells (3 of 3).

Reovirus oncolysis as a novel purging strategy for autologous stem cell transplantation.

Hematologic stem cell rescue after high-dose cytotoxic therapy is extensively used for the treatment of many hematopoietic and solid cancers. Gene marking studies suggest that occult tumor cells within the autograft may contribute to clinical relapse. To date purging of autografts contaminated with cancer cells has been unsuccessful.