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Neuropathology Of Neuro-Ophthalmic Disorders
Published in Vivek Lal, A Clinical Approach to Neuro-Ophthalmic Disorders, 2023
Lymphomas can rarely involve orbit and ocular adnexal structures. Orbital lymphomas are usually seen in older age-group. Majority of the orbital lymphomas are B-cell type (97%). Among B-cell lymphomas, almost all types of lymphoma have been reported in the orbit. The low-grade B-cell lymphomas outnumber the high-grade B-cell lymphomas. Among the low-grade B-cell lymphomas in orbit, marginal zone lymphoma (MALToma) is the commonest type, followed by follicular lymphoma and mantle cell lymphoma. Low-grade B-cell lymphomas are composed of small size lymphocytes which are 1–1.5 times the size of mature lymphocytes, and they exhibit nodular to diffuse architecture. The MALTomas show presence of lymphoepithelial lesions. Among high-grade lymphomas, diffuse large B-cell lymphoma (DLBCL) is the commonest type. It shows diffuse architecture and is composed of large lymphoid cells, 2–3 times the size of mature lymphocytes containing frequent mitoses (Figure 25.19a). Immunohistochemistry is essential for exact categorization of the lymphoma, which is essential for adequate management (Figure 25.19a). MALToma and follicular lymphoma usually carry good prognosis, while mantle cell lymphoma and DLBCL are associated with poor prognosis.39,40
Cutaneous Lymphomas
Published in Ayşe Serap Karadağ, Lawrence Charles Parish, Jordan V. Wang, Roxburgh's Common Skin Diseases, 2022
Emily Correia, Shalini Krishnasamy, Neda Nikbakht
Differential diagnosis: Staging workup including imaging studies must be conducted to exclude cutaneous involvement of other types of marginal zone lymphomas. Secondary involvement of other lymphomas typically effects the head and neck of older adults. Urticaria, arthropod bites, and leukemia cutis should be included in the differential diagnosis.
Head and neck cancer
Published in Peter Hoskin, Peter Ostler, Clinical Oncology, 2020
The parotid is a relatively common site of extranodal non-Hodgkin lymphoma. Typically, this will be a marginal zone (MALTOMA) or diffuse large B cell lymphoma. Localized disease (stage I or IIa) can be treated by low dose (24 Gy) radiotherapy alone if indolent and short-course chemotherapy followed by radiotherapy for more aggressive lymphomas. Full course chemotherapy will be needed if there is more widespread lymphoma.
Orbital marginal cell lymphoma and mantle cell lymphoma subclone in patient with monoclonal gammopathy of unknown significance
Published in Orbit, 2021
Sitara H. Hirji, Michelle M. Maeng, Andrea A. Tooley, Craig Soderquist, Joseph Annunziata, Michael Kazim
Orbital lymphomas are rare, comprising 1% of all non-Hodgkin lymphomas.2 The majority of such lymphomas are extranodal marginal zone B cell lymphomas, as was the stem line of the case presented above. Ocular adnexal mantle cell lymphoma is most commonly found in older men, and it has a tendency to present bilaterally in the context of disseminated stage IV disease.21 The standard treatment for isolated marginal zone orbital lymphomas is radiation therapy alone,22 and that for isolated mantle cell orbital lymphoma is chemotherapy with or without radiation therapy.21 In this case, however, systemic treatment with rituximab was recommended due to the presence of the mantle cell subclone. The presence of lymphoid clonal expansion in peripheral blood and possible colonic involvement in the patient’s past medical history further supported the need for systemic treatment. To date, the patient has experienced incomplete response to rituximab alone.
Splenic marginal zone B-cell lymphoma associated with ruptured breast implants: case report and review of the literature
Published in Case Reports in Plastic Surgery and Hand Surgery, 2021
Mark G. Evans, Melissa A. Mueller, Frederik Chen, Larry S. Nichter
Splenic marginal zone B-cell lymphoma is a rare malignancy, accounting for less than 2% of all lymphoma cases [12]. It was first described in 1992 and is now considered a separate entity in the World Health Organization (WHO) classification [13]. The three types of marginal zone B-cell lymphomas are splenic marginal zone lymphoma (SMZL), nodal marginal zone lymphoma (NMZL), and extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma). The diagnosis of SMZL is made based on lymphocyte morphology, immunophenotype, cytogenetic abnormalities, bone marrow histology, and spleen histology if available. When microscopic examination of the spleen is not possible, clinical splenomegaly and typical morphologic and immunophenotypic blood and bone marrow findings are sufficient to make a diagnosis.
Use of electron microscopy to study megakaryocytes
Published in Platelets, 2020
Cyril Scandola, Mathieu Erhardt, Jean-Yves Rinckel, Fabienne Proamer, Christian Gachet, Anita Eckly
Remarkably, the ultrastructure of in situ and in vitro mature MKs display somme clear differences (Figure 2aii-iii). Firstly, in situ MKs contain α- and δ-granules having a similar appearance as in platelets. In contrast, cultured MKs contain numerous multivesicular bodies (MVBs) displaying internal vesicles and an electron dense matrix [26,27]. Another important distinction is the marginal zone of the cells. In situ, mature MKs are bordered by a thick peripheral zone (PZ) rich in actin filaments which forms a continuous network surrounding the entire cell. On the contrary, this actin-rich zone is absent from cultured MKs. Instead, the microtubules are located in the periphery of maturing MKs and fill the cortex of the proplatelets [28,29]. The exact role of the actin-rich PZ in situ remains poorly understood. It has been proposed that it forms a barrier preventing the premature extension of proplatelets until the MK is correctly located to release platelets [11,30]. More recently, we observed that short projections originate from this PZ and play a crucial role in the early phases of MK transendothelial crossing [31].