Journal of Hematopathology最新文献

Lymphocytic variant of hypereosinophilic syndrome (LV-HES) is a rare T-cell lymphoproliferative disorder characterized by an immunophenotypically abnormal Th2 T-cell clone which produces eosinophilopoietic cytokines, resulting in eosinophilia and end-organ damage. A 38-year-old woman presented to an outside institution with a 10-year history of a pruritic, recurrent, steroid-responsive skin eruption and a 3-year history of mild lymphadenopathy. Excisional lymph node biopsy demonstrated a clonal, surface CD3-CD4+ T-cell infiltrate, prompting a diagnosis of peripheral T-cell lymphoma, not otherwise specified. Further workup revealed bone marrow and peripheral blood involvement. She received multiagent chemotherapy with temporary resolution of her skin eruption and lymphadenopathy, but persistent bone marrow disease. Presenting to our institution 3 years later, she exhibited numerous flesh-colored papules involving the extremities, without patches or plaques of mycosis fungoides. Skin biopsies demonstrated a dermal perivascular and interstitial proliferation of monotonous small T-cells without significant epidermotropism. T-cell receptor gene rearrangement studies of skin and peripheral blood specimens revealed identical clonal peaks, and peripheral blood flow cytometry showed persistence of the previously identified T-cell clone. Laboratory workup demonstrated a markedly elevated IgE level (66,580 kU/L) with a normal eosinophil count and IL-5 level. Next-generation sequencing of a peripheral blood sample revealed a pathogenic STAT3 S614R variant, previously documented in LV-HES. Although lacking eosinophilia, the patient's indolent course, characteristic skin lesions, steroid responsiveness, and pathologic features are typical of LV-HES, and the elevated IgE and STAT3 activation underscore a similar biology. We thus propose that this case expands the spectrum of indolent Th2-T cell lymphoproliferative disorders that need to be distinguished from peripheral T-cell lymphoma clinically.

A 56-year-old male presented to the clinic with complaints of multiple skin lesions. A complete blood count (CBC) was not available. No constitutional symptoms were present, and physical examination revealed tender skin lesions of the back, arms, legs, and scalp. A skin punch biopsy showed fragments of skin with extensive lymphoid infiltrates. The initial lymphoma workup by immunohistochemistry demonstrated negative staining for CD45, CD3, and CD20. Additional stains were performed which revealed the atypical lymphoid infiltrate to be positive for PAX5, TdT, CD10, CD34, CD79a, and CD99 and negative for CD4, CD8, Keratin, S100, CD56, CD138, and EMA. These histologic and immunophenotypic findings supported the diagnosis of skin involvement by B-lymphoblastic leukemia/lymphoma (B-ALL/LBL). Consequent peripheral blood and bone marrow biopsy evaluations supported this diagnosis. To avoid misdiagnosis, it is important to remember that B-ALL/LBL can rarely present as a skin lesion and can be negative for the most commonly used lymphoma immunohistochemical markers: CD45, CD3, and CD20. Additionally, skin involvement by B-ALL/LBL, although very uncommon, is most often reported in children or young adults, unlike this unique case occurring in an adult.

Testicular follicular lymphoma (TFL) is an exceedingly rare lymphoma that typically occurs in young male patients and is now recognized as a distinct diagnostic entity in the International Consensus Classification. TFL shows some clinicopathologic and genetic overlap with pediatric-type follicular lymphoma (PTFL). We report a case of TFL occurring in an otherwise healthy 4-year-old boy who presented with painless scrotal swelling. Orchiectomy revealed a 1.5-cm left testicular mass. Histologic sections showed a dense lymphoid infiltrate with nodular/follicular architecture growing between the seminiferous tubules. The infiltrate was composed of CD20/PAX5-positive B-cells that coexpressed germinal center markers (CD10, BCL6, MEF2B); they were negative for BCL2. No BCL2 or BCL6 rearrangements and no TNFRSF14 deletion were detected by FISH. Chromosomal microarray analysis detected copy-neutral loss of heterozygosity (CN-LOH) at 1p36.33-p36.32 (region of TNFRSF14). Next-generation sequencing detected variants in GNA13, RHOA, and TNFRSF14. In conclusion, this case shows the classic clinical, pathologic, and genetic features of TFL and highlights the similarities to PTFL and the importance of distinguishing this entity from other subtypes of FL. Patients with TFL typically respond favorably to orchiectomy and chemotherapy and have excellent clinical outcomes.

Primary gastric T-cell lymphomas (PGTL) are exceedingly rare with an estimated incidence of 0.0091 per 100,000 person-years, affecting mainly elderly males. PGTL can present with a variety of gastrointestinal symptoms, but patients only rarely present with perforation. We report the case of a 68-year-old male who presented to the emergency department with a history of chronic abdominal pain that was localized to the epigastrium over the last few days. Computed tomography (CT) identified pneumoperitoneum. Exploratory laparotomy revealed gastric antral perforation. Histologically, perforation margins were diffusely involved by large pleomorphic lymphoma cells with multilobated nuclei and focal anaplastic morphology. Immunohistochemically, neoplastic cells were positive for CD3 (partial), CD4, CD5, CD7, CD43, CD45, BCL2, and BCL6 (dim). The neoplastic cells were negative for CD1a, CD2, CD8, CD10, CD20, CD21, CD23, CD30, CD34, CD56, ALK1, TdT, lysozyme, CXCL13, ICOS, PD1, myeloperoxidase (MPO), human herpesvirus-8 (HHV-8), and keratin. Ki-67 showed a proliferation rate of 80-90%, and in situ hybridization was negative for Epstein-Barr virus. Polymerase chain reaction (PCR) of the T-cell receptors gamma (TRG) and beta (TRB) demonstrated monoclonal peaks. Quantitative PCR for HTLV-1 integration was negative. The diagnosis was peripheral T-cell lymphoma, not otherwise specified, stage IV, consistent with primary gastric lymphoma. To better understand this neoplasm, we performed a comprehensive English language literature review, retrieving clinical, pathologic, immunophenotypic, and molecular data when available, and discussed the most relevant features for diagnosis and classification using the 5th edition of World Health Organization, as well as prognostic features and outcomes of this lymphoma.

Leprosy, caused by Mycobacterium leprae (M. leprae), primarily manifests with cutaneous and peripheral nerve involvement. Systemic involvement, particularly in the bone marrow, is exceedingly rare. This report presents a case of lepromatous leprosy with bone marrow involvement, emphasizing the systemic nature of the disease and the importance of comprehensive diagnostic and management approaches. We aim to present a case of lepromatous leprosy with bone marrow involvement, detailing the clinical presentation, diagnostic evaluation, and management approach. A 65-year-old male with lepromatous leprosy and severe erythema nodosum leprosum developed pancytopenia. After undergoing comprehensive clinical evaluation, including history taking, physical examination, and laboratory investigations, bone marrow examination and molecular diagnostics using polymerase chain reaction (PCR) were performed to confirm the presence of M. leprae as an etiology for his pancytopenia. The bone marrow aspirate revealed hypercellularity with erythropoiesis and thrombopoiesis within normal limits. Foamy histiocytes with erythrophagocytosis were observed, along with the presence of M. leprae on Modified Ziehl-Neelsen stain. Molecular analysis confirmed M. leprae DNA in the bone marrow aspirate. Treatment with multi-drug therapy (MDT) and thalidomide resulted in normalization of blood counts and healing of skin lesions. This case underscores the systemic nature of leprosy and the rarity of bone marrow involvement, highlighting the importance of thorough evaluation in cases of persistent symptoms. Comprehensive diagnostic approaches, including bone marrow examination and molecular diagnostics, are essential for accurate diagnosis and timely initiation of appropriate treatment, ultimately improving patient outcomes and minimizing disease complications.

Anaplastic large cell lymphoma with primary presentation in, and disease limited to, the central nervous system (primary CNS ALCL) is a rare and aggressive lymphoma found in a sensitive anatomic site. We report the clinical and pathologic characteristics of 17 primary CNS ALCL cases that are newly reported from six academic medical centers. We are investigating the characteristics of these cases, alongside their commonalities and differences from systemic ALCL arising at conventional anatomic sites. Clinical, pathologic, and outcome data were extracted by medical record review. The median patient age was 32 years with a male-to-female ratio of 2.4:1. Cases presented with either localized or multifocal central nervous system (CNS) disease without coinciding systemic disease. Histologically, the common pattern prevailed, and loss of pan-T-cell markers was frequent. There was a similar proportion of anaplastic lymphoma kinase (ALK) positivity in primary CNS ALCL (12/17, 71%) compared to that reported in systemic ALCL (70-80%). Our data indicate a 5-year overall survival (OS) rate of 65% and a 5-year progression-free survival (PFS) rate of 48%. Five patient deaths occurred in this study of which all were in the ALK-negative group, and all were patients over 40 years old. ALK-positive patients were significantly younger than ALK-negative patients, and survival analyses showed that both ALK-positive and younger age (≤ 40 years) were favorable prognostic factors. This is the largest series of primary CNS ALCL reported to date, which demonstrates a high proportion of ALK-positive cases and favorable outcomes for both younger and ALK-positive patients despite the involvement of a sensitive anatomic site.

Targeted immunotherapy is a promising approach in treating high-risk and refractory/relapsed lymphoid malignancies. Although this strategy has shown a significant success in treating non-Hodgkin B-cell lymphomas and plasma cell myeloma, relapse with loss of targeted antigen can occur. Rarely, complete loss of multiple lineage specific markers can happen. We are describing 2 cases of B-cell neoplasms along with contributing immunohistochemistry, cytogenetic, and molecular results. Post-targeted CAR-T therapy, both cases, one aggressive B-cell lymphoma and the other plasma cell myeloma, lost B-cell, and plasma cell antigens, respectively. Complete loss of lineage specific markers post-targeted therapy is a rare event that makes the diagnosis of the relapsed neoplasm challenging. In this article, we also reviewed the literature and highlighted possible mechanisms of antigen loss following targeted therapy.