Impact of Systemic Inflammatory and Autoimmune Diseases on Outcomes in Patients With Myelodysplastic Syndrome and Chronic Myelomonocytic Leukemia.

[OBJECTIVE] Systemic inflammatory and autoimmune diseases (SIADs) are frequently reported in association with myeloid neoplasms; however, their prognostic relevance in myelodysplastic syndromes (MDS) and chronic myelomonocytic leukemia (CMML) remains unclear. This study aimed to evaluate the frequency of SIADs and their impact on survival outcomes in patients with MDS and CMML.

[MATERIALS AND METHODS] We retrospectively analyzed patients diagnosed with MDS, CMML, or acute myeloid leukemia transformed from MDS between 2000 and 2020. Medical records were reviewed for the presence of SIADs, demographic and laboratory characteristics, bone marrow findings, cytogenetics, treatments, and responses. Overall survival (OS), progression-free survival (PFS), and leukemia-free survival (LFS) were assessed.

[RESULTS] A total of 178 patients were included (mean age 66.5 years; 52.2% male). MDS was diagnosed in 75.3% of cases, most commonly refractory cytopenia with multilineage dysplasia, while 15% had CMML. SIADs were identified in 29.7% of patients, most frequently Hashimoto's thyroiditis, seronegative arthritis, Behçet syndrome, and panniculitis. Patients with SIADs were significantly younger than those without SIADs (P = .005). No significant differences were observed in gender, comorbidities, cytogenetic risk, or baseline laboratory parameters. Overall survival, progression-free survival, and leukemia-free survival were comparable between groups. Although SIADs were associated with a nonsignificant trend toward increased disease progression and leukemic transformation, high-risk disease scores were independently associated with inferior survival outcomes.

[CONCLUSION] SIADs were common in patients with MDS and CMML but did not significantly affect survival outcomes, supporting previous reports that SIADs may not independently influence prognosis in this population.