Analysis of correlation between the number of circulating DLBCL cells and marrow tumor burden by FCM and its clinical significance / 中华检验医学杂志

ABSTRACT

Objective:To investigate the correlation between the number of circulating DLBCL cell and the marrow tumor cell burden and the prognostic indicators in patients with DLBCL, and to evaluate the feasibility of circulating DLBCL cell reflecting the marrow tumor burden and disease progression. Optimization of FCM for screening circulating DLBCL cell was done to monitor MRD and recurrence.Methods:We conducted a retrospective study in 75 diagnosed DLBCL patients in the First Affiliated Hospital of Zhengzhou University from June 2020 to February 2021, including 43 males and 32 females aged 61 (37-85) years. According to the diagnosis and treatment criteria, the patients were divided into initial and recurrence group ( n = 53), partial response(PR)group ( n=14) and complete response(CR)group ( n=8). According to the positive criteria of circulating DLBCL cells, 48 cases were divided into circulating DLBCL positive group and 27 cases were negative group. 30 anemia patients with non-B-cell tumor-related diseases were selected as the control group, including 16 males and 14 females, aged 52 (30-79) years. 70 healthy subjects, including 36 males and 34 females, aged 39 (25-57), were selected for methodology optimization. FCM was used to detect the ratio of marrow and circulating DLBCL cells in each group, and analyze the connection between circulating DLBCL cells and clinical indicators. Statistical analysis was performed using t test, χ 2 test, Kruskal-Wallis H test, Spearman rank correlation, and Logistic regression. Results:(1) Bone marrow and circulating DLBCL cells were not detected in CR group and control group; The positive rate of circulating DLBCL cells in the initial/recurrent group and PR groups was 75.47% and 57.14%, respectively. The proportion of bone marrow and circulating DLBCL cells was positively correlated in the two groups ( P value was <0.001 and 0.020, respectively). (2) The proportion of bone marrow and circulating DLBCL cells in the initial and recurrent groups, PR group, CR group and control group decreased successively ( P<0.05). The proportion of DLBCL cells was 27.72% (initial and recurrent bone marrow group), 26.92% (initial and recurrent circulating group), 3.23% (bone marrow PR group) and 1.67% (circulating PR group), respectively. (3) Compared with the negative group, the circulating DLBCL cell positive group had increased LDH, β 2-MG, and CMYC expression(≥80%), with decreased LYM, HGB<100 g/L, B symptoms, PD-L1 expression, and age ≥60 years, showing higher ECOG, aaIPI/IPI scores and Ann staging ( P<0.05). Age ≥60, B symptoms, and PD-L1 expression were independent risk factors for circulating DLBCL cells ( P<0.05). Conclusions:The detectable rate of circulating DLBCL cell could be improved by optimizing the preoperative treatment conditions of FCM. Circulating DLBCL cells can reflect the tumor burden and disease progression. Detecting circulating DLBCL cells may improve patients′ compliance.