Immune-mediated diseases and immunodeficiencies associated with thymic epithelial neoplasms

Introduction: This retrospective study aimed to characterize the clinical hematological and immunological features of patients with thymic epithelial neoplasms. Methods: From a cohort of 512 patients with thymic epithelial neoplasms, 79 patients diagnosed with autoimmune/immunodeficiency conditions or signs and/or symptoms suggesting an autoimmune or immunodeficiency state were evaluated by standard immunological and hematological testing. Results: Elevated percentages of CD2+, CD3+, and CD8+ lymphocytes were observed in 44 (57.1%), 33 (41.8%), and 32 (40.5%) patients. Low CD4+ and CD19+ percentages were observed in 25 (31.6%) and 36 (46.2%), respectively; CD4+:CD8+ ratios were inverted in 18 (22.8%). IgG, IgA, and IgM levels were low in 12 (15.8%), 9 (11.7%) and 15 (19.7%) patients, respectively. Patients with immunodeficiency condition(s) were more likely to have high CD8+ percentages (p=0.040), low CD19+ percentages (p=0.025), and/or inverted CD4+/CD8+ ratios (p=0.034). Patients with autoimmune condition(s) were more likely to have a high/normal CD4+ percentage (p=0.038). High CD2+ percentages were associated with lower mean IgG and IgA levels (p=0.030 and p=0.017, respectively). High CD3+ and CD8+ percentages were associated with lower mean IgA levels (p=0.046 and p=0.013, respectively). Low CD19+ percentages were associated with lower mean IgG and IgA levels (p=0.004 and p<0.001, respectively). Conclusion: Signs/symptoms and history of autoimmune and immunodeficiency conditions among patients with thymic epithelial neoplasms are associated with high frequencies of abnormalities in immunoglobulin levels and lymphocyte immunophenotypes, suggesting a role for their assessment.