Cutaneous manifestations of methotrexate-associated lymphoproliferative disorders: report of two cases and a review of the literature

Cutaneous Methotrexate-Related Epstein-Barr Virus-Positive Diffuse Large B-Cell Lymphoma in a Patient with Granulomatous Cutaneous T-Cell Lymphoma: A Case Report and Literature Review

Methotrexate-related lymphoproliferative disorders (MTX-LPDs) are immunodeficiency diseases following methotrexate (MTX) administration, mainly occurring in rheumatoid arthritis patients. Although uncommon, MTX-LPDs have been reported in some patients with psoriasis, dermatomyositis, and cutaneous T-cell lymphoma (CTCL) who received MTX. Granulomatous mycosis fungoides (GMF) is a rare subtype of cutaneous T-cell lymphoma, where MTX is one of the treatment options in recalcitrant cases. Herein, we report a case of a 72-year-old female patient with GMF who additionally developed cutaneous Epstein-Barr virus (EBV)-positive diffuse large B-cell lymphoma (DLBCL) during MTX treatment. According to the 5th edition of the WHO classification of Haematolymphoid Tumors (WHO-HAEM), this condition is currently categorized as "lymphoma arising in immunodeficiency/dysregulation". In this article, we also reviewed published literature on cutaneous MTX-LPDs in the setting of CTCL. This entity should be considered in cases of new, atypical skin nodules and/or plaques in CTCL patients receiving long-term MTX treatment.

Skin-Limited, Methotrexate-Associated Epstein-Barr Virus-Positive Mucocutaneous Ulcer-A Mimicker of High-Grade Lymphoma. A Report of 4 Cases and Review of the Literature

ABSTRACT

Immunodeficiency-associated lymphoproliferative disorders (IA-LPDs) constitute a diverse range of conditions including posttransplant lymphoproliferative disorders, other iatrogenic IA-LPDs, and lymphoproliferative disorders associated with an underlying primary immune disorder or HIV infection. IA-LPDs are clinically and pathologically heterogeneous, and there is a lack of standardization of diagnostic terminology. They can represent a potential serious diagnostic pitfall because the histological features of clinically indolent proliferations may mimic those of high-grade lymphoma. However, correct identification of these entities is essential given that complete remission may occur upon reversal of the underlying cause of immunosuppression without the need for systemic therapy. IA-LPDs presenting in the skin are rare but well documented. One form of iatrogenic IA-LPD, methotrexate-associated lymphoproliferative disorder (MTX-LPD), can present with cutaneous nodules, plaques, or ulcers. Predominantly, MTX-LPD develops in the context of long-term treatment of autoimmune conditions, such as rheumatoid arthritis, dermatomyositis, and Sjögren syndrome, and may be associated with underlying Epstein-Barr virus (EBV) infection. We present 4 cases of cutaneous EBV-positive B-cell MTX-LPD and describe their clinical and morphological findings. Comparison of our histological findings to the diagnostic criteria for EBV-positive mucocutaneous ulcer (EBVMCU) revealed significant overlap, highlighting the intersection between MTX-LPD and EBVMCU. Withdrawal of methotrexate resulted in healing of all lesions at a mean time of 2 months. In summary, close clinicopathological correlation is vital to identify MTX-LPD presenting as cutaneous EBVMCU given that the initial treatment strategy is that of withdrawal of methotrexate without the need for immediate systemic therapy.

Primary cutaneous methotrexate-associated B-cell lymphoproliferative disorders other than EBV-positive mucocutaneous ulcer: clinical, pathological, and immunophenotypic features

Methotrexate (MTX)-associated B-cell lymphoproliferative disorders (B-LPD) may first present in the skin. Epstein-Barr virus (EBV)-positive mucocutaneous ulcer (EBVMCU) is now a well known disease listed in the 2017 World Health Organization classification. However, primary cutaneous MTX-associated B-LPD (pcMTX B-LPD), other than EBVMCU, appear to be underestimated, and their distinctiveness remains unproven. This study aimed to document the clinicopathological characteristics of nine patients with pcMTX B-LPD that were not EBVMCU to extend our understanding of this peculiar disease. The cohort included three males and six females, with a median age of 74 years (range 54-83 years). All patients were treated with MTX for RA. Of nine patients, four presented with a solitary lesion, and five had multiple lesions. Histologically, five cases showed a polymorphic pattern, and four showed a monomorphic pattern. Immunohistochemically, four cases showed positive EBER staining, and one showed positive CD5 staining. In eight cases, once pcMTX B-LPD was diagnosed, methotrexate was immediately withdrawn. All eight of these patients experienced spontaneous regression and achieved complete remission (CR), without relapse. The patient with CD5 positivity received cytotoxic chemotherapy as the initial treatment. This patient achieved a CR after the initial treatment, but eventually experienced disease relapse resulting in death. We also revealed that pcMTX B-LPD and MTX-associated EBVMCU exhibited similar biological behaviours. We concluded that most pcMTX B-LPD cases could be cured by stopping MTX treatment. We also highlighted the fact that pcMTX B-LPD and MTX-EBVMCU had overlapping features. This finding suggested that pcMTX B-LPD and MTX-EBVMCU might share an underlying mechanism.

Clinical management for other iatrogenic immunodeficiency-associated lymphoproliferative disorders

Other iatrogenic immunodeficiency-associated lymphoproliferative disorders (OIIA-LPD), a category of immunodeficiency-associated LPD according to the World Health Organization classification, is associated with immunosuppressive drugs (ISDs). Several factors, including autoimmune disease (AID) activity, Epstein-Barr virus (EBV) infection, ISD usage, and aging, influence the development of OIIA-LPD, resulting in complicated clinical courses and outcomes. Most OIIA-LPD develops in patients with rheumatoid arthritis using methotrexate (MTX-LPD). The management of MTX-LPD is based on the clinical course, i.e., with/without regression, with/without relapse/regrowth event (RRE), LPD subtype, and ISDs for AIDs after LPD development. There are three clinical courses after ISD withdrawal: regressive LPD without relapse/regrowth (R-G), regressive LPD with RRE (R/R-G), and persistent LPD (P-G). The majority of EBV+ diffuse large B-cell lymphomas are classified in R-G, whereas classic Hodgkin lymphoma is generally classified in R/R-G. Polymorphic LPD (P-LPD) in MTX-LPD develops with heterogeneous pathological features similar to monomorphic LPD. Chemotherapy for MTX-LPD is selected according to that for de novo LPD, although the strategy for aggressive P-LPD and non-specific LPD is not well established. The absolute lymphocyte count in the peripheral blood has been suggested as a candidate marker for MTX-LPD development and RRE. Several clinical issues, including correct diagnosis among overlapping clinicopathological features in MTX-LPD and clinical management of LPD by ISDs other than MTX, require further investigation.

Methotrexate-Associated Lymphoproliferative Disorder: Dermoscopic Features

Methotrexate-related lymphoproliferative disorder (MTX-LPD) is a rare disorder caused by long-term MTX therapy for autoimmune diseases. There has been no report of the dermoscopic features of MTX-LPD to date. A 64-year-old female presented with a slightly elevated indurated erythematous plaque with scales on her right thigh. The patient had been treated for rheumatic arthritis with MTX and prednisolone for more than 15 years, and 18 mg/week MTX without prednisolone had been administered in the last year. Dermoscopy revealed dotted vessels and glomerular vessels on pink homogeneous areas and multiple surface scales. Enhanced computed tomography showed multiple nodules and lymphadenopathies at the mediastinum and axillae. Histopathological examination revealed telangiectasia in the superficial dermis. Atypical lymphoid cells were scattered in the whole dermis and subcutaneous tissue. A perivascular infiltrate of atypical lymphocytes and histiocytoid cells partially destroyed the vessel walls. Epstein-Barr virus in situ hybridization showed a positive result. The cessation of MTX reduced the erythematous plaque, and lymphadenopathies at the neck, mediastinum, and axillae were not palpable. We discuss the relevance of these dermoscopic and histopathological features. The accumulation of such cases will reveal the dermoscopic features of MTX-LPD and the utility of dermoscopy for the diagnosis of MTX-LPD.