Risk Factors of Disseminated Tumor Cells in the Bone Marrow of Patients With Angioimmunoblastic T-Cell Lymphoma and Their Impact on Prognosis.

Abstract

Introduction: Angioimmunoblastic T-cell lymphoma (AITL) is a mature T-cell proliferative tumor characterized by an aggressive clinical course and low incidence. The risk factors for the presence of disseminated tumor cells (DTCs) in the bone marrow (BM) of patients and their impact on prognosis remain incompletely understood. In this study, we used multiparametric flow cytometry (MFC) to detect DTCs in the BM of AITL patients. We aimed to assess risk factors for the presence of DTCs, investigate correlations between the immunophenotype of DTCs and clinical indicators or efficacy, and identify prognostic factors. Our findings provide insights that may aid in the early diagnosis, disease monitoring, and efficacy evaluation of AITL.

Methods: Based on the presence or absence of DTCs in the BM, 90 patients with an initial diagnosis of AITL were classified into DTCs⁺ and DTCs^- groups. The differences between the two groups were then compared. Clinical and survival data were collected from AITL patients to analyze the correlations between immunophenotypes and clinical characteristics or prognosis. Univariate logistic regression was employed to analyze the factors influencing efficacy.

Results: MFC detected neoplastic T cells of AITL in 65.56% (59/90) of BM samples. Compared to the DTCs^- patients, DTCs⁺ patients had a higher frequency of fever, splenomegaly, extranodal involvement ≥ 2 sites, and elevated lactate dehydrogenase (LDH). The 2-year progression-free survival (PFS) rates were 31.3% and 52.5%, and the 2-year overall survival (OS) rates were 65.6% and 65.3% in the DTCs⁺ and DTCs^- groups, respectively. Multivariate survival analysis demonstrated that pleural effusion was a risk factor affecting PFS and OS. Furthermore, loss of CD7 expression on DTCs was associated with shorter OS. AITL patients with CD7 loss were more likely to present with rash, elevated immunoglobulins, and CXCL13 loss by histopathological immunohistochemistry. Finally, CD3 expression, elevated LDH, and decreased hemoglobin (HGB) were collectively identified as high-risk factors for disease progression.

Conclusion: The presence of DTCs in the BM is associated with the prognosis of AITL. Pleural effusion constitutes an independent adverse prognostic factor. Loss of CD7 correlates with shorter OS, and a profile combining CD3 expression, elevated LDH, and decreased HGB serves as a useful predictor of disease progression.