Volume 1, Issue 2, September 2016


MDS or M6: The dilemma in classifying early leukemias Page 74-76
X. Frank Zhao


The many rare faces of follicular lymphoma – Part 2 Page 77-89
Stefano Fratoni and X. Frank Zhao

Follicular lymphoma (FL), a well defined mature B-cell lymphoma, rarely presents with great morphological variations that could mimic either other malignancies or disguise themselves with only subtle neoplastic feature. In the second part of this series, we present more FL morphologic variants, including FL with signet ring cells, FL with HRS-like cells, FL with anaplastic/pleomorphic cells, FL with sclerosis, FL microlymphoma, FL with prominent sinus histiocytosis, and FL neurolymphomatosis. Although uncommon, some of these FL variants pose diagnostic pitfalls for the practicing pathologists.

Case Reports

EBV-positive gastric plasmablastic lymphoma in an HIV-negative adult Page 90-95
Eva M. Amenta, Elvira A. Allakhverdieva, John C. Huston, and Neil G. Haycocks

Plasmablastic lymphoma (PBL) is a rare B-cell lymphoma most commonly observed in the oral mucosae of HIV-positive patients, with increasing recognition of cases occurring in HIV-negative individuals. There is a noted association between PBL and Epstein-Barr virus (EBV), and chromosomal rearrangements involving c-MYC have been implicated in oncogenesis. There have been eight previously described cases of PBL involving the stomach in HIV-negative patients. This report details the first known case of EBV- positive gastric PBL, which was identified in an 82-year-old HIV-negative man. The patient was treated with CHOP-based chemotherapy followed by radiation, and expired eleven months after the initial diagnosis. PBL may be an under recognized entity when it presents in HIV-negative individuals, and should be considered in the differential diagnosis of high-grade lymphomas with plasmacytic or plasmablastic differentiation. Further studies are required to elucidate the pathogenesis of this neoplasm and define optimal treatment strategies.

CD34 positive dysplastic giant platelets masquerading as blasts on flow cytometry Page 96-101
Anmaar Abdul-Nabi, Yvette Reese, Susan Treese, John L. Frater, and Nabeel R. Yaseen

Giant platelets are commonly seen in myelodysplastic syndrome (MDS), however their immunophenotypic characteristics are not well studied. Here we report a patient with a history of MDS that demonstrated a dysplastic, immunophenotypically abnormal subpopulation of giant platelets. In this patient, flow cytometric analysis of the marrow aspirate showed that 59% of events were with characteristics of CD34 positive blasts, raising the possibility of acute leukemia. However, microscopic examination of the bone marrow aspirate smears showed only 8% blasts and many dysplastic giant platelets. Immunohistochemistry showed CD34 positivity in the patient’s megakaryocytes. Flow cytometric analysis of the patient’s peripheral blood platelets showed that the dysplastic platelets were positive for CD34. This case shows that large dysplastic platelets in MDS may express CD34 and show CD45 staining and side scatter characteristics similar to blasts and can cause a dramatic but spurious increase in the blast count detected by flow cytometry.

ALK-positive Anaplastic Large Cell Lymphoma presenting as a solitary bladder neoplasm: A case report and review of the literature Page 102-107
Ying Huang, Ji Yuan, Hong He, Xiaomei Li, Qiubo Yu, Gang Li, and Dan Li

Anaplastic large-cell lymphoma (ALCL) with involvement of the urinary bladder is rare. We report a unique case of ALK-positive ALCL in a 17-year-old male patient. He presented with dysuria for three months and gross hematuria for one month. The computed tomography scan and the cystoscopy revealed a single broad-based lesion measuring 3×2 cm on the right lateral wall of the urinary bladder. There was no lymphadenopathy and no tumor outside of the bladder. Biopsy of the lesion showed diffuse large pleomorphic cells infiltrating the lamina propria and strongly expressing CD30, ALK, and T-cell markers. A clonal TCR-gamma gene rearrangement was detected by PCR and ALK gene rearrangement was observed by fluorescence in situ hybridization. The patient was not treated and remains asymptomatic 6 months after the diagnosis. This is the eleventh documented instance of ALCL involving the bladder and the second reported cases of localized primary bladder ALK-positive ALCL.

Central nervous system relapsed B-Lymphoblastic Leukemia with t(9;22)(q34;q11) BCR/ABL1 mimicking acute myeloid leukemia Page 108-113
Ruijun J Su, Eric C Huang, and Mingyi Chen

The presence of the Philadelphia (Ph) chromosome is one of the worst prognostic factors in B-cell acute lymphoblastic leukemia (B-ALL). Cerebrospinal fluid (CSF) involvement is a high-risk factor and serious complication in patients with B-ALL. Here we report a 21-year-old female diagnosed with Ph positive B-ALL and subsequently developed CSF relapse and rapid demise. Her CSF contained numerous blasts resembling myeloblasts. The relevant clinicopathologic distinctive scenarios and differential diagnoses are discussed.