Eyelid erythema as the first manifestation of subcutaneous panniculitis-like T-cell lymphoma mimicking dermatomyositis: a case-based review

Panniculitis: a narrative review

Panniculitis is associated with a variety of disease processes that can be challenging to distinguish clinically. While diagnosis often relies on histopathology, sometimes this is not sufficiently diagnostic, which requires careful consideration of clinical features. We sought to provide an overview of the most common adult noninfectious panniculitis by reviewing not only the histological distinguishing features but also the clinical characteristics of various types of panniculitis including patient history, distribution, morphology, and other clues. A narrative review of both common and rare panniculitis primarily affecting the adult patient population was performed, with focus on recent English language publications. Additionally, both traditional and emerging therapeutic options are discussed. This article focused on diseases affecting predominantly adult populations and does not detail pediatric panniculitis or infectious etiologies. Overall, histopathology remains a key component in the diagnosis of panniculitis, but clinical characteristics provide substantial aid.

Hematologic malignancies and hematopoietic stem cell transplantation

Paraneoplastic neurologic syndromes are rarely associated with hematologic malignancies. In their rarity, lymphomas are the diseases with more frequent paraneoplastic neurologic syndrome. High-risk antibodies are absent in most lymphoma-associated paraneoplastic neurologic syndromes, with the exception of antibodies to Tr/DNER in paraneoplastic cerebellar degeneration, mGluR5 in limbic encephalitis, and mGluR1 in some cerebellar ataxias. Peripheral nervous system paraneoplastic neurologic syndromes are rare and heterogeneous, with a prevalence of demyelinating polyradiculoneuropathy in non-Hodgkin lymphoma. Polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, skin changes (POEMS) is a rare, paraneoplastic syndrome due to an underlying plasma cell disorder. The diagnosis is based on defined criteria, and vascular endothelial growth factor (VEGF), not an antibody, is considered a reliable diagnostic marker that also mirrors therapy response. As with the paraneoplastic neurologic syndromes in solid tumors, therapies rely on cancer treatment associated with immunomodulatory treatment with better response in PNS with antibodies to surface antigens. The best outcome is generally present in Ophelia syndrome/limbic encephalitis with anti-mGluR5 antibodies, with frequent complete recovery. Besides patients with isolated osteosclerotic lesions (where radiotherapy is indicated), hematopoietic stem-cell transplantation is the therapy of choice in patients with POEMS syndrome. In the paraneoplastic neurologic syndromes secondary to immune checkpoint inhibitors, discontinuation of the drug together with immunomodulatory treatment is recommended.