Long-term complete remission of multiple extranodal natural killer/T-cell-type posttransplant lymphoproliferative disorder after surgical resection: a case report

Epstein-Barr Virus-Associated Lymphomatoid Papules: A Sign of Immunosuppression Resembling Lymphomatoid Papulosis

ABSTRACT

Epstein-Barr virus (EBV)-positive lymphoproliferative disorders associated with immunodeficiency constitute a spectrum of lymphoid and plasma cell proliferations that vary in cytomorphology, immunophenotype, and clinical behavior. CD30-positive cutaneous lymphocytic infiltrates with EBV expression and lymphomatoid papulosis-like presentations have been rarely reported. This retrospective study assessed the clinical and histopathological characteristics of EBV-positive cases with papulonodular morphologies and CD30 positivity seen by Northwestern Medicine Dermatopathology. Twelve patients (7M:5F, mean age 69 years) were presented with papular cutaneous lesions without antecedent patch/plaque disease. Nine cases were associated with known immunosuppression in the setting of transplant-related therapies (n = 4), hematopoietic malignancy (n = 2), post-transplant hematopoietic malignancy (n = 1), and autoimmune disease treatment (n = 2). Two patients had age-related immunosenescence. Four patients demonstrated EBV viremia; for 2 patients, this finding comprised the first sign of immunosuppression. Workup was negative for systemic lymphoma in all patients. Various treatment strategies were used, including observation (n = 3), discontinuation/reduction of immunosuppression (n = 3), rituximab (n = 4), and steroids (n = 4). At mean 30-month follow-up, 4 patients (33.3%) were alive, 3 with and 1 without disease. Eight patients (67.6%) had died, 3 after lesional resolution and 5 with recurrent disease. Biopsies revealed mixed lymphoid infiltrates composed of atypical CD30-positive T cells (n = 5) or B cells (n = 7) with variable EBV-encoded small RNA expression. These cases suggest clinicopathologic presentations resembling lymphomatoid papulosis with atypical, large CD30-positive, EBV-positive cells could comprise first sign of potentially serious immunodeficiency and should prompt evaluation for EBV viremia. These cases also broaden the current picture of immunodeficiency-associated lymphoproliferative disorders to include lymphomatoid papulosis-like clinical presentations.

Natural Killer Cells in Post-Transplant Lymphoproliferative Disorders

Post-transplant lymphoproliferative disorders (PTLDs) are life-threatening complications arising after solid organ or hematopoietic stem cell transplantations. Although the majority of these lymphoproliferations are of B cell origin, and are frequently associated with primary Epstein-Barr virus (EBV) infection or reactivation in the post-transplant period, rare cases of T cell and natural killer (NK) cell-originated PTLDs have also been described. A general assumption is that PTLDs result from the impairment of anti-viral and anti-tumoral immunosurveillance due to the long-term use of immunosuppressants in transplant recipients. T cell impairment is known to play a critical role in the immune-pathogenesis of post-transplant EBV-linked complications, while the role of NK cells has been less investigated, and is probably different between EBV-positive and EBV-negative PTLDs. As a part of the innate immune response, NK cells are critical for protecting hosts during the early response to virus-induced tumors. The complexity of their function is modulated by a myriad of activating and inhibitory receptors expressed on cell surfaces. This review outlines our current understanding of NK cells in the pathogenesis of PTLD, and discusses their potential implications for current PTLD therapies and novel NK cell-based therapies for the containment of these disorders.

Immunodeficiency-associated lymphoproliferative disorders: time for reappraisal?

Immunodeficiency-associated lymphoproliferative disorders (IA-LPDs) are pathologically and clinically heterogeneous. In many instances, similar features are shared by a spectrum of IA-LPDs in clinically diverse settings. However, the World Health Organization (WHO) classifies IA-LPDs by their immunodeficiency setting largely according to the paradigm of posttransplant lymphoproliferative disorders but with inconsistent terminology and disease definitions. The field currently lacks standardization and would greatly benefit from thinking across immunodeficiency categories by adopting a common working vocabulary to better understand these disorders and guide clinical management. We propose a 3-part unifying nomenclature that includes the name of the lesion, associated virus, and the specific immunodeficiency setting for all IA-LPDs. B-cell lymphoproliferative disorders (LPDs) are usually Epstein-Barr virus (EBV)⁺ and show a spectrum of lesions, including hyperplasias, polymorphic LPDs, aggressive lymphomas, and, rarely, indolent lymphomas. Human herpes virus 8-associated LPDs also include polyclonal and monoclonal proliferations. EBV^- B-cell LPDs and T- and NK-cell LPDs are rare and less well characterized. Recognition of any immunodeficiency is important because it impacts the choice of treatment options. There is an urgent need for reappraisal of IA-LPDs because a common framework will facilitate meaningful biological insights and pave the way for future work in the field.

Native lung pneumonectomy for post-transplantation lymphoproliferative disorder refractory to rituximab following contralateral lung transplantation

Post-transplantation lymphoproliferative disorder (PTLD) is a life-threatening complication following lung transplantation. We report a PTLD case of high-grade, B-cell lymphoma following contralateral single-lung transplantation. The disease involved the liver, right kidney and right native lung. While the PTLD affecting the abdominal organs regressed with rituximab chemotherapy, the native lung disease progressed and was treated surgically (right pneumonectomy). Some aspects are unique in this case: (i) different response to medical treatment between lung and abdominal organs; (ii) absolute absence of involvement of the native lung and (iii) surgical treatment with a pneumonectomy, still very rarely described in the literature. We hypothesized that a different morphotype of the disease involved the abdominal organs or the penetrance of rituximab, and chemotherapy could have been impaired by the presence of pulmonary fibrosis.