Abstract 10
Category: Clinical

At the end of the session, participants will be able to:

  1. By the end of this session, participants will be aware of the range of non-diffuse large B-cell lymphomas affecting the CNS, as well as their classifications and main differential diagnoses.
  2. Participants will also be able to recognize the major radiological and pathological findings in each of these non-diffuse large B-cell lymphomas affecting the CNS.

COI Disclosure:

None to disclose.

Presenter

I was a practicing board certified dermatologist in Iran before my immigration with my family to Canada in July 2017. After writing Canadian licensing exams and receiving my LMCC, I did a year of dermatopathology fellowship with late Dr. Ghazarian at University Health Network, then started my residency in Anatomical Pathology in 2020.
Currently, I am an Anatomical Pathology resident, PGY5 at University of Toronto.

Authors

Niloofar Sina1, Chris Heyn2, Co-senior authors: Zeina Ghorab1, Julia Keith1
1Laboratory Medicine and Molecular Diagnostics, Sunnybrook Health Sciences Centre, Laboratory Medicine and Pathobiology, University of Toronto
2Diagnostic Imaging, Sunnybrook Health Sciences Centre, University of Toronto

    Target Audience:

    Pathologists

    CanMEDS:
    Medical Expert (the integrating role), Scholar, Professional

    A 13 -year Review of Non-Diffuse Large B Cell Lymphomas of the Central Nervous System at a Tertiary Hospital; a Case Series Study

    Abstract

    Background: Non-diffuse large B cell lymphomas (non-DLBCL) of the central nervous system (CNS) are rare. The rarity of such involvement poses a diagnostic challenge for neuropathologists and increases the risk of misclassification, particularly in the absence of a preceding lymphoma diagnosis.
    Patients and methods: In this retrospective study, we reviewed the clinicopathologic and imaging characteristics of seventeen cases of non-DLBCL of the CNS diagnosed from 2010 to 2022 by neuropathology at our tertiary hospital.

    Results: The seventeen cases included eight primary lymphomas and nine secondary lymphomas of the CNS, fifteen neurosurgical cases and two autopsies. The tumours were extra-axial in nine9 and intra-parenchymal in eight cases, thirteen cases were B cell origin (including nine small mature B cell lymphomas, three large B cell lymphomas and one pleomorphic posttransplant lymphoproliferative disorder) and four cases were T cell origin (including two peripheral T cell lymphoma not otherwise specified, one anaplastic T cell lymphoma, ALK negative and one case of disseminated mycosis fungoides). Four distinct radiographic patterns were appreciated on central imaging review.

    Conclusion: Our study highlights the heterogeneity of non-DLBCL lymphomas of CNS. This associated with their rarity and variable atypical features increases the risk of misdiagnosis. Reports such as this foster consensus of the diagnostic and management strategies of these rare entities.

    Keywords: central nervous system, lymphoma, non-diffuse large B cell lymphoma