Adult T-cell Leukemia/Lymphoma as a Methotrexate-associated Lymphoproliferative Disorder in a Patient with Rheumatoid Arthritis

Human T-lymphotropic virus type 1 and antiretroviral therapy: practical considerations for pre-exposure and post-exposure prophylaxis, transmission prevention, and mitigation of severe disease

Human T-lymphotropic virus type 1 (HTLV-1) is a retrovirus associated with substantial risk of secondary (often life-threatening) disease for the estimated 10 million to 20 million people infected globally. Despite a clear need, no HTLV-1-specific vaccine or antiretroviral therapy has been developed to date. Instead, existing public and primary health-care interventions inadequately focus on infection prevention and management of secondary diseases. In this Personal View, we discuss the evidence that exists to support the sensitivity of HTLV-1 to antiretroviral therapies approved by the US Food and Drug Administration for the treatment of HIV-1, how this sensitivity is affected by clinically relevant virological and immunological features, and additional practical considerations for the use of antiretroviral therapies in the context of HTLV-1.

Effect of HTLV-1 Infection on the Clinical Course of Patients with Rheumatoid Arthritis

Human T-cell leukemia virus type 1 (HTLV-1) is the causative agent of adult T-cell leukemia/lymphoma (ATL) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). The effects of HTLV-1 on health are not fully elucidated. Epidemiological studies have shown that the prevalence of HTLV-1 infection is high in patients with rheumatic diseases. The prevalence of comorbidities, such as Sjögren’s syndrome and rheumatoid arthritis (RA), is higher in patients with HAM/TSP than the in general population. Studies have shown the effects of HTLV-1-infection on the clinical course of RA. Major questions on the association between HTLV-1 infection and RA: (1) Is it possible that HTLV-1 infection causes RA? (2) Do patients with RA who are infected with HTLV-1 have different clinical features? (3) Are immunosuppressants associated with an increased prevalence of HAM/TSP or ATL in RA patients with HTLV-1 infection? Is ATL an immunosuppressive therapy-associated lymphoproliferative disorder? No large-scale studies have investigated the incidence of ATL in patients with RA. However, several studies have reported the development of ATL in patients with RA who have HTLV-1 infection. This review aimed to shed light on the association between HTLV-1 infection and RA and summarize the unmet medical needs of RA patients with HTLV-1 infection.

The Association of Increase of Human T-Cell Leukemia Virus Type-1 (HTLV-1) Proviral Load (PVL) With Infection in HTLV-1-Positive Patients With Rheumatoid Arthritis: A Longitudinal Analysis of Changes in HTLV-1 PVLs in a Single Center Cohort Study

Objective

We evaluated changes of HTLV-1 proviral loads (PVLs) during treatment for rheumatoid arthritis (RA) and investigated whether these changes affect the clinical course in HTLV-1-positive RA patients.

Methods

A total of 41 HTLV-1-positive RA patients were analyzed. Their clinical picture including disease activity [Disease Activity Score in 28 joints-erythrocyte sedimentation rate (DAS28-ESR), DAS28-CRP, simplified disease activity index (SDAI), and clinical disease activity index (CDAI)] and comorbidity were evaluated over a 2-year period. PVLs from peripheral blood mononuclear cells were investigated by real-time polymerase chain reaction (PCR). We investigated whether HTLV-1 PVLs is altered, or which clinical characteristics affect changes of HTLV1-PVLs during 2-year treatment.

Results

Clinical disease activity was not changed during the 2-year observational period. The mean HTLV-1 PVL value change from baseline to 2 years was -1.2 copies/1000 PBMCs, which was not statistically significant. No baseline clinical characteristics influenced changes in HTLV-1 PVL. However, a numerical change of HTLV-1 PVLs was increased in 4 patients initiating the new biological/targeted synthetic disease-modifying antirheumatic drugs (b/tsDMARDs) at 2−10 months after starting the new b/ts DMARDs (numerical increase was 24.87 copies/1000 PBMCs). Infection occurred in 4 patients, and 3 of those patients showed an increased HTLV-1 PVL. Univariate analysis revealed an association between increase of HTLV-1 PVL and incidence of infection.

Conclusions

Over 2 years, HTLV-1 PVL did not significantly change in our HTLV-1-positive RA patients. Individual changes in HTLV-1 PVL were correlated with incidence of infection but not disease activity which indicate that we may take precaution toward infection at the uptick of HTLV-1 PVL in HTLV-1-positive RA patients.

Case Report: Composite Angioimmunoblastic T-Cell Lymphoma and Epstein-Barr Virus-Positive B-Cell Lymphoproliferative Disorder as Other Iatrogenic Immunodeficiency-Associated Lymphoproliferative Disorders

Immunosuppressants are widely used to treat patients with rheumatoid arthritis (RA), and their adverse effects have been known to cause other iatrogenic immunodeficiency-associated lymphoproliferative disorders (OIIA-LPDs). We report a patient with RA who had been treated with methotrexate (MTX) and tacrolimus (TAC) and who developed whole body lymphadenopathy. We simultaneously confirmed angioimmunoblastic T-cell lymphoma (AITL) through a right cervical lymph node biopsy and Epstein-Barr virus-positive B-cell lymphoproliferative disorder (EBV-positive B-LPD) through a bone marrow examination. After cessation of immunosuppressant therapy, both LPDs completely disappeared. Patients with AITL are occasionally reported to develop B-cell lymphoma through reactivation of the EBV, which leads to clonal expansion in the microenvironment. Immunohistochemistry results revealed that both LPD components were positive for EBV-encoded RNA. Moreover, in this patient, the plasma EBV DNA level was found to be high; therefore, EBV infection was a probable etiology. Synchronous coexistence of AITL and B-LPD as an OIIA-LPD has rarely been reported. This case report is the first to discuss the disappearance of both LPDs on withdrawal of immunosuppressants only. AITL occasionally accompany B-LPD; however, this composite lymphoma comprised AITL and B-LPD, and OIIA-LPDs should not be overlooked.

Bilateral Wrist Tenosynovitis owing to Acute Conversion of Adult T-Cell Leukemia-Lymphoma in a Patient with Rheumatoid Arthritis

Human T-cell leukemia virus type 1- (HTLV-1-) associated arthritis is a relatively common disease. However, tenosynovitis owing to adult T-cell leukemia-lymphoma (ATL) is a rare condition. To the best of our knowledge, there have been no reports of tenosynovitis caused by conversion to acute ATL from one of the other ATL types. We present the case of a 60-year-old woman with rheumatoid arthritis (RA) with bilateral wrist tenosynovitis owing to the conversion to acute ATL from one of the other ATL types. She had swelling around the bilateral wrist joint under well controlled RA inflammation. She had no symptoms, physical findings, or laboratory findings indicative of conversion to acute ATL from one of the other ATL types. She underwent tenosynovectomy on the volar and dorsal sides of the left wrist joint to diagnose the cause of swelling around the bilateral wrist joint. Pathological analysis revealed diffuse proliferation of medium-sized atypical CD4(+) lymphocytes. Interestingly, she was diagnosed with wrist tenosynovitis caused by an acute ATL type. This diagnosis suggested that clinicians must consider ATL in connection with atypical wrist tenosynovitis in HTLV-1-endemic areas.

Effective Treatment with Tocilizumab in a Rheumatoid Arthritis Patient Complicated with Human T-cell Leukemia Virus Type 1-associated Myelopathy

A 61-year-old woman with human T-cell leukemia virus type 1 (HTLV-1)-associated myelopathy (HAM)/tropical spastic paraparesis (TSP) and interstitial pneumonia (IP) was admitted to our hospital. She complained of sicca symptoms, polyarthralgia, and swollen joints. She was diagnosed with rheumatoid arthritis (RA) and Sjögren's syndrome. Methotrexate and anti-tumor necrosis factor therapy were not utilized because of the inclusion of severe respiratory disorders among the complications and the neurological symptoms of HAM/TSP. Tocilizumab monotherapy improved the RA disease activity without exacerbating HAM/TSP. The present case suggests that tocilizumab might be a suitable treatment option in patients with RA and HAM/TSP.

HTLV-1 Infection and Rheumatic Diseases

Some major research and clinical questions about human T-cell leukemia virus type 1 (HTLV-1) infection and rheumatic diseases remain: (1) Does HTLV-1 infection cause rheumatic diseases? (2) Do patients with rheumatic diseases display different responses to treatment with anti-rheumatic agents when they are HTLV-1 carriers? (3) Is adult T-cell leukemia/lymphoma (ATL) or HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) more prevalent in HTLV-1 carriers with rheumatic diseases who are treated with anti-rheumatic agents? These questions are important because increasing numbers of patients with rheumatic diseases are currently receiving treatment with aggressive medicines such as immunosuppressants and biologics. Studies on HTLV-1 gene-transgenic mice have shown manifestations resembling rheumatic diseases. Epidemiological studies have shown a high incidence of HTLV-1 infection in patients with rheumatic diseases including rheumatoid arthritis (RA), Sjogren’s syndrome, and polymyositis. HTLV-1-positive and HTLV-1-negative patients with RA have displayed similar immunological features including the seroprevalence of anti-citrullinated peptide antibodies. Conversely, attenuated effectiveness of tumor necrosis factor inhibitors for HTLV-1-positive patients with RA in Japan has been reported. Therefore, although no direct evidence has shown that HTLV-1 infection alone causes rheumatic diseases, HTLV-1 may affect the inflammation of RA. Although the incidence of ATL or HAM/TSP among patients with rheumatic diseases has not been investigated in large-scale studies, ATL or HAM/TSP has developed among HTLV-1-positive patients with rheumatic diseases. HTLV-1 infection may affect the clinical course of patients with rheumatic diseases, particularly after receiving anti-rheumatic agents. Because studies on these issues are limited, further investigation with large sample sizes is necessary.

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.

Other Iatrogenic Immunodeficiency-Associated Lymphoproliferative Disorders with a T- or NK-cell phenotype

Other iatrogenic immunodeficiency-associated lymphoproliferative disorders (OIIA-LPDs) with a T- or NK-cell phenotype are markedly rare, with only a limited number of cases having been reported thus far. Methotrexate (MTX) is the most common agent used for OIIA-LPD patients, and 43 cases of MTX-associated T-LPDs (MTX T-LPDs) and five cases of MTX-associated NK/T-LPDs (MTX NK-LPDs) have been described. In addition to MTX T-LPDs and MTX NK/T-LPDs, T-LPD and NK/T-LPDs have been reported in patients receiving other immunosuppressive agents such as thiopurines, TNF antagonists, and cyclosporine. Hepatosplenic T-cell lymphoma (HSTL) is specifically associated with iatrogenic immunodeficiency, and 10% of HSTL cases develop in patients receiving thiopurines and/or TNF antagonists for inflammatory bowel disease (IBD). In this review, we focused on MTX T-LPD, MTX NK/T-LPD, and HSTL in patients with IBD. These T- and NK/T-cell associated OIIA-LPDs are the most common in daily medical practice.

Methotrexate-associated lymphoproliferative disorders of T-cell phenotype: clinicopathological analysis of 28 cases

Methotrexate-associated lymphoproliferative disorders are categorized as "other immunodeficiency-associated lymphoproliferative disorders in the WHO classification. Methotrexate-associated lymphoproliferative disorder is mainly a B-cell lymphoproliferative disorders or Hodgkin lymphoma type, whereas T-cell lymphoproliferative disorders are relatively rare (4-8%). Only a small number of methotrexate-associated T-cell lymphoproliferative disorders have been detailed thus far. Because of the rarity, methotrexate-associated T-cell lymphoproliferative disorder has not been well studied and its clinicopathological characteristics are unknown. A total of 28 cases of methotrexate-associated T-cell lymphoproliferative disorders were retrospectively analyzed. Histologically and immunohistochemically, they were divided into three main types: angioimmunoblastic T-cell lymphoma (n = 19), peripheral T-cell lymphoma, NOS (n = 6), and CD8⁺ cytotoxic T-cell lymphoma (n = 3). Among the 28 cases, only one CD8⁺ cytotoxic T-cell lymphoma case was Epstein-Barr virus-positive. The other 27 cases were negative for Epstein-Barr virus on tumor cells, but scattered Epstein-Barr virus-infected B-cells were detected in 24 cases (89%), implying the reactivation of Epstein-Barr virus caused by immunodeficient status of the patients. After the diagnosis of methotrexate-associated T-cell lymphoproliferative disorder, methotrexate was immediately withdrawn in 26 cases. Twenty (77%) cases presented with spontaneous regression. Compared to methotrexate-associated B-cell lymphoproliferative disorder, patients with methotrexate-associated T-cell lymphoproliferative disorder had a significantly higher proportion of males (p = 0.035) and presence of B-symptoms (p = 0.036), and lower proportion of Epstein-Barr virus⁺ tumor cells (p < 0.001). Although the difference was not significant, the methotrexate-associated T-cell lymphoproliferative disorder also had more frequent spontaneous regression (p = 0.061). In conclusion, methotrexate-associated T-cell lymphoproliferative disorder was divided into three main types: angioimmunoblastic T-cell lymphoma, peripheral T-cell lymphoma, NOS, and CD8⁺ cytotoxic T-cell lymphoma. Angioimmunoblastic T-cell lymphoma was the most common type. Methotrexate-associated T-cell lymphoproliferative disorder was characterized by a high rate of spontaneous regression after methotrexate cessation. Epstein-Barr virus positivity was relatively rare in methotrexate-associated T-cell lymphoproliferative disorder, significantly less frequent than methotrexate-associated B-cell lymphoproliferative disorder, suggesting different pathogenesis.

Clinical features and human T-cell leukemia virus type-1 (HTLV-1) proviral load in HTLV-1-positive patients with rheumatoid arthritis: Baseline data in a single center cohort study

Objective: Recently, Human T-cell leukemia virus type-1 proviral load (HTLV-1 PVL) has been evaluated as an important predictor of adult T-cell leukemia/lymphoma (ATL) in HTLV-1 carriers. We aimed to evaluate whether HTLV-1 PVL is also important for the development of ATL among HTLV-1-positive patients with rheumatoid arthritis (RA).Methods: We established a cohort of 82 HTLV-1-positive RA patients between 2017 and 2018. Of those, 27 (32.9%) were treated with biological disease-modifying anti-rheumatic drugs (bDMARDs) with/without methotrexate. We measured HTLV-1 PVL in peripheral blood mononuclear cells (PBMCs) at study entry and compared the value by clinical status and treatment options.Results: The median PVL for all was 9.6 copies per 1000 PBMCs without sex difference (male 17.2 and female 8.6; p = .24). The median PVL was significantly higher for patient's comorbid bronchiectasis, malignancies, and opportunistic infectious diseases, compared with patients without comorbidity. There were no significant differences in PVL levels among types of bDMARDs, although the level was tended to be higher for patients treated with JAK inhibitor.Conclusions: HTLV-1 seropositive RA patients comorbid for any diseases having higher HTLV-1 PVLs will be a higher risk for developing ATL. Careful follow-up of these patients is necessary to detect ATL development.

The time-sequential changes of risk factors for adult T-cell leukemia development in human T-cell leukemia virus-positive patients with rheumatoid arthritis: a retrospective cohort study

Objective: This study aimed to investigate the time-sequential changes of risk factors for adult T-cell leukemia (ATL) development in human T-cell leukemia virus type 1 (HTLV-1)-positive rheumatoid arthritis (RA) patients. Methods: HTLV-1 infection was screened using particle agglutination assay and confirmed via western blotting in 365 RA patients. Twenty-three HTLV-1-positive RA patients were included in the study cohort. Blood samples were obtained from these patients at each observation time point. The values of HTLV-1 proviral load (PVL) and serum soluble IL-2 receptor (sIL2-R), which are risk factors for ATL development, were measured using real-time PCR and enzyme immunoassay, respectively. Results: The study cohort comprised 79 person-years. The median HTLV-1 PVL and sIL2-R values of the HTLV-1-positive RA patients were 0.44 copies per 100 white blood cells (WBCs) and 406 U/mL, respectively. Three HTLV-1-positive RA patients showed a high PVL value. No remarkable changes were observed in the PVL and sIL2-R values during the observation period. However, one elderly HTLV-1-positive RA patient who had a high PVL value developed ATL during treatment with methotrexate and infliximab. Conclusion: A thorough clinical assessment of the risk factors for ATL development may be necessary in daily clinical practice for RA patients in HTLV-1-endemic areas in Japan.