Aplastic anemia related to thymoma: a survey on behalf of the French reference center of aplastic anemia and a review of the literature

[Pure white cell aplasia combined with thymoma and lung cancer: a case report and literature review]

Pure white cell aplasia (PWCA) is a rare hematologic disorder. In this case study, a 67-year-old man presented with severe neutropenia along with thymoma and lung cancer. A comprehensive diagnostic approach was done which included routine blood test, bone marrow cytology, bone marrow pathology, flow cytometry, and thymic pathology. Other potential causes, such as pure red blood cell aplasia and myelodysplastic syndrome, were ruled out. The final diagnosis was determined to be thymoma-related PWCA. Continuous treatment with human granulocyte colony-stimulating factor (G-CSF) was ineffective for treating PWCA in this patient. The patient's white blood cell and neutrophil count increased following treatment with cyclosporine and subsequently returned to normal levels by the 8th day after thymectomy. A recurrence of PWCA was identified 40 days after the operation and coincided with COVID-19 infection. The patient eventually succumbed to a severe infection. Therefore, in cases of severe neutropenia with an unclear etiology, prompt evaluation of mediastinal and bone marrow status is imperative.

Clinical efficacy of thoracoscopic surgery by subxiphoid approach for thymoma and its influence on intraoperative blood loss and postoperative complications

OBJECTIVE

To evaluate the clinical efficacy of thoracoscopic surgery by subxiphoid approach for patients with thymoma and its influence on intraoperative blood loss and postoperative complications.

METHODS

From January 2019 to January 2020, 90 patients who underwent thoracoscopic surgery were enrolled and evenly divided into a control group receiving surgery by lateral thoracic approach and an experimental group adopting the subxiphoid approach according to different surgical approaches, and their clinical data were retrospectively analyzed. The clinical efficacy, perioperative indexes, postoperative complications, pulmonary function, and inflammatory factors were compared between the two groups. Generic Quality of Life Inventory-74 (GQOLI-74) was used to assess the quality of life of the patients before and after surgery, and Mini-Mental State Examination (MMSE) was used to assess their mental state. The Numerical Rating Scale (NRS) was used to evaluate the postoperative pain of the two groups.

RESULTS

After treatment, the total clinical effectiveness rate of the experimental group was significantly higher than that of the control group (P<0.05). The experimental group obtained superior results in perioperative index and fewer postoperative complications compared with the control group (P<0.05). Better performance of FEV1 and FVC was observed in the experimental group than the control group (P<0.05). The experimental group had significantly higher postoperative GQOLI-74 scores (P<0.001) and MMSE scores (P<0.05) than the control group. Lower levels of C-reactive protein (CRP), and tumor necrosis factor-α (TNF-α), and lower NRS scores at 12 h and 24 h after surgery were witnessed in the experimental group compared to the control group (P<0.05).

CONCLUSION

For patients with thymoma, the thoracoscopic surgery by subxiphoid approach is safe and effective, and can reduce the intraoperative blood loss and postoperative complications.

Myasthenia gravis and paroxysmal nocturnal hemoglobinuria after thymectomy: A rare association

Paroxysmal nocturnal hemoglobinuria (PNH) is a very rare clonal autoimmune disease manifesting with hemolysis, thrombosis, or bone marrow failure. We present an atypical association of myasthenia gravis, aplastic anemia, and PNH occurring years after thymectomy. While this association might be extremely rare, it may not be coincidental as there is a common pathophysiology between PNH and aplastic anemia, with the latter reported in several thymoma/thymectomy cases. Eculizumab was introduced with good efficacy and without safety concern in our patient, leading to long-term control of PNH without worsening of myasthenia gravis.

A case of thymoma showing significant tumor reduction after anti-thymocyte globulin

A 71-year-old female with type B3 thymoma developed severe aplastic anemia. Anti-thymocyte globulin was administered with glucocorticoids and cyclosporin A as the treatment for aplastic anemia. Computed tomography scan revealed that thymoma apparently shrank and remained without regrowth for at least 7 months. As previously reported, glucocorticoid has therapeutic effects on thymoma especially with abundant lymphocytes. Anti-thymocyte globulin also depletes peripheral lymphocytes, but its efficacy in the treatment of thymoma is unknown. Anti-thymocyte globulin and glucocorticoids may have cooperated with each other in reducing thymoma in our case. More cases should be accumulated to elucidate the effects of anti-thymocyte globulin on thymoma.

Thymoma associated with severe pancytopenia and Good's syndrome: case report

We report a rare case of thymoma associated with pancytopenia and Good's syndrome. The patient was a previously healthy 60-year-old female who presented to the emergency department with a severe headache. Her initial work up was significant for a parenchymal hemorrhage and severe pancytopenia. A CAT scan of her chest, abdomen, and pelvis demonstrated a large mediastinal mass and core biopsy confirmed thymoma. Bone marrow aspirate was hypocellular. Initial multidisciplinary discussion recommended immunosuppressive therapy to treat her aplastic anemia prior to resection. However, she remained transfusion-dependent from her pancytopenia and required prolonged admission. Ultimately, the patient was unable to undergo immunosuppressive therapy due to persistent infection. Hematology/oncology believed that the initial response to immunosuppressive therapy would further compromise her immune function and would be detrimental for the patient. After undergoing thymectomy, she suffered from persistent severe pancytopenia, diarrhea, and pneumonia. She remained transfusion-dependent and despite remaining on broad spectrum antimicrobials, she continued to have fevers. She was diagnosed with Good's syndrome postoperatively after she was found to be hypogammaglobulinemic. She received intravenous immunoglobulin (IVIG) immediately, but ultimately expired from multi-system organ failure. This case report highlights the importance of early diagnosis and multidisciplinary treatment for patients who have hypogammaglobulinemia, severe pancytopenia, and thymoma. We recommend early treatment of IVIG.

Disseminated focal 18F-fluoro-deoxyglucose uptake upon granulocyte colony-stimulating factor therapy mimicking malignant bone infiltration: case report of a patient with very severe aplastic anemia

Combined ¹⁸F-fluoro-deoxyglucose ([18F]FDG) positron emission tomography and computed tomography ([18F]FDG-PET/CT) is increasingly used for the diagnostic and therapeutic management of hematologic and non-hematologic malignancies. Here, we describe a unique case of a patient presenting with very severe aplastic anemia and a mediastinal mass showing disseminated hypermetabolic lesions of the bones after receiving granulocyte colony-stimulating factor (G-CSF), highly suspicious for disseminated metastatic lesions. A 71-year-old patient presented with a 3 week history of dyspnea and fatigue. Blood tests showed severe pancytopenia and iliac crest bone marrow biopsy revealed an extensively hypoplastic bone marrow. Diagnostic work-up by histology, conventional cytogenetics and flow cytometry confirmed the diagnosis of very severe aplastic anemia. Besides blood transfusions, the patient was treated with G-CSF. Furthermore, computed tomography revealed a suspect mass in the anterior mediastinum, presenting with moderate glucose metabolism in the subsequent [18F]FDG-PET/CT scan. In addition, multiple disseminated and highly metabolic bone lesions of primarily the ribs were detected, suspicious of malignant bone infiltration. Since physiologic bone marrow activation by G-CSF-stimulation could not be ruled out, G-CSF therapy was interrupted to repeat the PET/CT scan 10 days later. On the second [18F]FDG-PET/CT the moderately hypermetabolic mediastinal mass persisted. However, the initially FDG-avid bone lesions almost completely resolved, rendering the diagnosis of G-CSF-induced bone marrow hypermetabolism very likely without the need for further invasive diagnostic procedures. The mediastinal mass was thereafter histologically verified as thymoma. Interpretation of [18F]FDG-PET/CT in patients with aplastic anemia may be complicated by the frequent therapeutic use of G-CSF. With G-CSF, islets of residual bone marrow activity can be visualized on [18F]FDG-PET/CT images that might be misinterpreted as malignant bone infiltration. Repeating PET/CT scan after G-CSF discontinuation can prevent unnecessary invasive diagnostic procedures in these patients.

Aplastic anemia in a patient with CVID due to NFKB1 haploinsufficiency

Acquired aplastic anemia (AA) is a life-threatening bone marrow failure caused by an autoimmune cytotoxic T lymphocyte attack on hematopoietic stem and progenitor cells. Factors contributing to aberrant autoimmune activation in AA include a deficit of T regulatory cells and high levels of inflammatory cytokines. Several acquired conditions of immune dysregulation and genetic polymorphisms in inflammatory cytokines and human leukocyte antigen genes have been linked to an increased risk of AA. However, AA has not been reported in patients with Mendelian disorders of immune regulation. Here we report a patient with familial common variable immunodeficiency (CVID) caused by a pathogenic variant in NFKB1, who developed AA as an adult. The patient had a difficult clinical course and was unable to tolerate standard AA therapy with cyclosporine A and eltrombopag, with complications attributed in part to the effect of cyclosporine A on NF-κB signaling. Our case suggests a novel link between genetic disorders of immune regulation and AA and highlights the importance of recognizing inherited autoimmunity syndromes in AA patients for the selection of optimal therapy and prognostic counseling.

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.