Graft-versus-host disease-type colitis: an unusual association of malignant thymoma

Remission of Thymoma on Steroid Therapy in a Patient With Atypical Thymoma-Associated Multiorgan Autoimmunity: A Case Report and Literature Review

In up to 34% of cases, thymoma, itself a rare neoplasm, is accompanied by autoimmune disorders, two of which are thymoma-associated multiorgan autoimmunity (TAMA) and paraneoplastic autoimmune multiorgan syndrome (PAMS). Unfortunately, differential diagnosis between these two entities can be challenging since no strict PAMS definition exists and PAMS can overlap with a subgroup of TAMA patients with skin lesions as leading presentation. We present a case of a 68-year-old woman with a diagnosis of thymoma accompanied by myasthenia gravis, hypothyroidism and GvHD-like mucocutaneous lesions that initially could account to both TAMA and PAMS diagnosis. However, following the exclusion of humoral autoimmunity against components of epithelial cells junction, TAMA was finally established. Interestingly, the introduction of corticosteroid therapy for TAMA symptom management resulted in unexpected partial remission of thymoma with no impact on mucocutaneous lesions. Our case study is an example of two extremely rare phenomena accompanying thymomas: unprecedented TAMA presentation with GvHD-like mucositis, which as we postulate should be placed in the spectrum of TAMA, and tumor remission on steroids.

Autoimmune disorders and paraneoplastic syndromes in thymoma

Thymomas are counted among the rare tumour entities which are associated with autoimmune disorders (AIDs) and paraneoplastic syndromes (PNS) far more often than other malignancies. Through its complex immunological function in the context of the selection and maturation of T cells, the thymus is at the same time highly susceptible to disruptive factors caused by the development and growth of thymic tumours. These T cells, which are thought to develop to competent immune cells in the thymus, can instead adopt autoreactive behaviour due to the uncontrolled interplay of thymomas and become the trigger for AID or PNS affecting numerous organs and tissues within the human body. While myasthenia gravis is the most prevalent PNS in thymoma, numerous others have been described, be they related to neurological, cardiovascular, gastrointestinal, haematological, dermatological, endocrine or systemic disorders. This review article sheds light on the pathophysiology, epidemiology, specific clinical features and therapeutic options of the various forms as well as courses and outcomes of AID/PNS in association with thymomas. Whenever suitable and backed by the limited available evidence, the perspectives from both the thymoma and the affected organ/tissue will be highlighted. Specific issues addressed are the prognostic significance of thymectomy on myasthenia gravis and other thymoma-associated AID/PND and further the impact and safety of immunotherapies on AID and PND relating to thymomas.

Autoimmune Pituitary Disease: New Concepts With Clinical Implications

Some endocrine disorders, including hypophysitis and isolated adrenocorticotropic hormone (ACTH) deficiency, are caused by an autoimmune response to endocrine organs. Although the pathogenesis of some autoimmune endocrine diseases has been elucidated, it remains obscure for most. Anti-PIT-1 hypophysitis (anti-PIT-1 antibody syndrome) is a newly described pituitary autoimmune disease characterized by acquired and specific growth hormone (GH), prolactin (PRL), and thyroid-stimulating hormone (TSH) deficiencies. This disorder is associated with a thymoma or neoplasm that ectopically expresses pituitary-specific transcription factor 1 (PIT-1) protein. Circulating anti-PIT-1 antibody is a disease marker, and PIT-1-reactive cytotoxic T cells (CTLs) play a pivotal role in disease development. In addition, isolated ACTH deficiency appears to be caused by autoimmunity to corticotrophs; however, the pathogenesis remains unclear. A recently described case of isolated ACTH deficiency with large cell neuroendocrine carcinoma (LCNEC) showed ectopically expressed proopiomelanocortin (POMC), and circulating anti-POMC antibody and POMC-reactive CTLs were also detected. As CTL infiltrations around corticotrophs were also observed, isolated ACTH deficiency may be associated at least in part with a paraneoplastic syndrome. Although several underlying mechanisms for pituitary autoimmunity have been proposed, these observations highlight the importance of paraneoplastic syndrome as a cause of pituitary autoimmune disease. In this review, we focus on the pathophysiology and connection of anti-PIT-1 hypophysitis and isolated ACTH deficiency and discuss the state-of-art knowledge for understanding pituitary autoimmunity.

A systematic review of paraneoplastic syndromes associated with thymoma: Treatment modalities, recurrence, and outcomes in resected cases

OBJECTIVE

Paraneoplastic syndromes associated with thymomas remain incompletely understood. The objective was to examine the association between surgically resected thymomas and paraneoplastic syndromes over the past half century.

METHODS

A primary PubMed/MEDLINE search was used to identify published articles describing paraneoplastic syndromes associated with thymomas from 1960 to 2019. A secondary search identified additional articles referenced in the articles found in the primary search. Kaplan-Meier and log-rank test were used for time-to-event data analyses.

RESULTS

From 407 articles describing 507 patients, 123 different paraneoplastic syndromes were associated with thymoma. The 5 most common paraneoplastic syndromes were myasthenia gravis, pure red cell aplasia, lichen planus, Good syndrome, and limbic encephalitis. Complete or partial resolution of paraneoplastic syndrome symptoms after surgery was noted in 76% of patients, of whom 21% had a relapse or new paraneoplastic syndrome onset after surgery. The most common adjunctive therapy associated with resolution of paraneoplastic syndrome was corticosteroids (30%). For all patients after surgery, thymoma recurrence was observed in 17% of cases, whereas recurrence of paraneoplastic syndrome was observed in 34% of cases, and both were observed in approximately 11% of cases. The 5- and 10-year overall survivals were 78% and 66%, respectively. Improved overall survival was associated with patients who had total resolution from paraneoplastic syndrome.

CONCLUSIONS

A comprehensive assessment of publications over the past half century suggests that a multimodal treatment approach that includes surgical resection of thymomas is able to achieve paraneoplastic syndrome resolution in a majority of patients. Onset of new paraneoplastic syndromes after surgery is associated with the recurrence of the first paraneoplastic syndrome, and resolution of paraneoplastic syndrome is associated with improved overall survival.

Successful combined treatment with thymectomy, rituximab and tocilizumab for severe thymoma-associated multi autoimmune syndrome

We present a 53-year-old woman who presented simultaneously with acute inflammatory demyelinating polyneuropathy, Graves' disease, leukocytoclastic vasculitis, elevated acetylcholine antibody receptor antibodies and a mediastinal mass. Thymectomy was performed and revealed a type A thymoma and the clinical picture and paraclinical findings were consistent with a thymoma-associated multi-autoimmune syndrome (TAMA). Beside prednisolone and plasmapheresis, the patient was treated with tocilizumab and rituximab. After surgical and immunomodulatory treatment with tocilizumab and rituximab the patient's condition slowly started to improve. TAMA is associated with a spectrum of autoantibodies and immune-mediated damage to multiple organs. Even if thymectomy is crucial for long term prognosis, aggressive immunomodulation should be considered early in the disease course, especially in cases showing involvement of the peripheral and/or central nervous system.

Thymoma-associated multiorgan autoimmunity with exclusive gastrointestinal tract involvement: case report and review of the literature

Thymoma-associated multiorgan autoimmunity (TAMA) is a recently delineated and rare paraneoplastic syndrome reported in patients with thymoma. The disorder is characterized by graft-versus-host disease-like pathology affecting the skin, gastrointestinal tract (GIT), and liver, and is usually associated with a poor outcome. We document a case of TAMA with exclusive GIT involvement which included the stomach, small and large bowel, presenting in a 66-year-old male patient 5 years after complete resection of a type B2 thymoma. A brief review is provided of this scarce syndrome, the GIT pathology described in the 21 TAMA cases reported to date, and the unique characteristics of patients with exclusive GIT involvement by this acquired autoimmune disorder.

Case of thymoma-associated cutaneous graft-versus-host disease-like disease successfully improved by narrowband ultraviolet B phototherapy

Thymoma-associated graft-versus-host disease (GVHD)-like disease is a rare paraneoplastic disease seen in patients with thymoma. Here, we describe the first case of thymoma-associated GVHD-like disease localized to the skin that was successfully improved by a combination of systemic corticosteroids and whole-body narrowband ultraviolet (UV)-B phototherapy. The patient had developed toxic epidermal necrolysis-like erosive skin lesions over the whole body. Although systemic corticosteroids were effective up to a point, we were unable to begin the steroid taper. The addition of systemic narrowband UV-B phototherapy improved the skin manifestation of this disease, allowing corticosteroids to be reduced to a third of the original dose. Histopathologically, it was confirmed that the proportion of Foxp3-positive lymphocytes in the skin increased after narrowband UV-B irradiation. We propose that whole-body narrowband UV-B phototherapy is a good therapeutic option for the skin manifestation of thymoma-associated GVHD-like disease.

Thymoma-Associated Graft-Versus-Host-Like Disease With Skin Manifestations Improved by Complete Resection of Thymoma

A 69-year-old woman with refractory skin eruptions, which had first appeared 3 years previously, was examined, and an anterior mediastinal tumor was detected. The tumor was resected, and a diagnosis of type B2 thymoma, stage III disease (according to the World Health Organization classification), was made. Retrospectively, histologic findings of the skin before the operation were consistent with graft-versus-host disease. The final diagnosis of her skin lesions was thymoma-associated graft-versus-host-like disease. The skin lesions improved gradually during the 1-month period after resection with only a topical steroid, and further improvement was seen at 3 months.

Diminished regulatory T cells in cutaneous lesions of thymoma-associated multi-organ autoimmunity: a newly described paraneoplastic autoimmune disorder with fatal clinical course

Thymoma-associated multi-organ autoimmunity is a rare, autoimmune disease that causes colitis, liver dysfunction and cutaneous graft-versus-host (GVH)-like skin damage. This paraneoplastic autoimmune disorder may be due to inadequate T cell selection in the tumour environment of the thymus. Although sporadic case reports have revealed its clinical features, little is known about its pathological mechanism. By comparing the skin-infiltrating T cell subsets with those of GVH disease (GVHD) and other inflammatory skin diseases, we sought to elucidate the pathological mechanism of thymoma-associated multi-organ autoimmunity. Histopathological and immunohistochemical analysis of skin biopsies was performed for three patients with thymoma-associated multi-organ autoimmunity. Histopathological findings of thymoma-associated multi-organ autoimmunity were indistinguishable from those of patients with acute GVHD, although the aetiologies of these diseases are completely different. The frequency of regulatory T cells (T(regs)) is reduced in cutaneous lesions and CD8+ cytotoxic T lymphocytes that massively infiltrate into the epidermis of patients with thymoma-associated multi-organ autoimmunity. Additionally, the ratio of T helper type 17 (Th17) cells to CD4+ cells in patients with thymoma-associated multi-organ autoimmunity and acute GVHD was higher than that in healthy controls, but similar to that in psoriasis vulgaris patients. Similarity of the skin-infiltrating T cell subsets with those of acute GVHD suggested that skin damage in patients with thymoma-associated multi-organ autoimmunity might be induced by self-reactive cytotoxic T lymphocytes under the diminished suppressive capacity of T(regs).

Chemotherapy improves thymoma-associated graft-versus-host-disease-like erythroderma

Graft-versus-host-disease (GVHD) with erythroderma can rarely occur in the context of thymoma and is associated with a poor prognosis due to an increased risk of infection-related death. The present study describes a case of a 50-year-old man with malignant thymoma who developed sepsis in addition to skin manifestations similar to that seen in GVHD. This patient experienced marked improvement in skin lesions in response to steroids and combination chemotherapy with carboplatin and paclitaxel, with subsequent resolution of infection. The present study describes the clinical course of this patient, followed by a review of pertinent reports of thymoma associated with GVHD with particular focus on the efficacy of treatment strategies.

Thymoma-associated graft-versus-host disease-like erythroderma

We report a 40-year-old woman with recurrent thymoma associated with myasthenia gravis, in whom an unusual form of erythroderma developed. A histological examination revealed a graft-versus-host disease (GVHD)-like reaction. After high-dose steroid therapy, the metastatic thymoma lesion in the abdominal cavity was reduced in size from 9.5 x 6 x 7.5 cm to 4 x 3 x 1 cm in diameter. Nevertheless, the GVHD-like erythroderma become aggravated, her condition worsened, and the patient finally suffered from respiratory failure and died of sepsis. A GVHD-like reaction may be a rare presentation of thymoma-associated immunological disorders such as myasthenia gravis or pure red cell aplasia. Herein, we discuss the present case and review pertinent reports of thymoma cases associated with GVHD.

Thymoma-associated multiorgan autoimmunity: A graft-versus-host–like disease

Graft-versus-host disease (GVHD) is a T cell-mediated disease seen most commonly after hematopoietic stem cell transplantation. Rarely, a GVHD-like disease can be seen in patients with malignant thymoma. We describe a 50-year-old man with malignant thymoma who developed skin, liver, and intestinal manifestations similar to that seen in GVHD. We also review other reported cases of GVHD-like manifestations in the setting of thymoma and propose "thymoma-associated multiorgan autoimmunity" as a name for this novel disease. Specifically, thymoma-associated multiorgan autoimmunity is defined as a disease of the liver, intestine, or skin, which on histopathology resembles GVHD but is seen in the setting of malignant thymoma and not after hematopoietic stem cell transplantation.

Thymoma with chronic diarrhea: report of two cases and review of the literature

Thymoma associated with hypogammaglobulinemia and profound susceptibility to recurrent and serious infections was first reported by Good in 1954, after whom it was named as Good's syndrome. Chronic diarrhea associated with thymoma is almost always seen in patients with hypogammaglobulinemia. However, chronic diarrhea in a setting of normal gammaglobulins have been rarely reported. We hereby report two cases of thymoma with normal immune functions, presenting with chronic diarrhea as the only symptom of thymic malignancy. We discussed the etiopathogenic relation between thymic pathology and diarrhea and review the cases of thymoma associated with chronic diarrhea in the English literature.