Clinical characteristics of 131 DLBCL patients.
The characteristics of the 131 patients with DLBCL (51 cases of GI-DLBCL patients and 80 N-DLBCL patients) were presented in Table 1. In 51 patients with GI-DLBCL, 31 (60.8%) patients were male and the median age was 67 years (range, 22-83 years).37 (72.4%) GI-DLBCL patients were categorized into Ann-arbor stage III-IV, and 32 (62.7%) patients had high level of IPI scores (IPI score >3). About half of the GI-DLBCL patients underwent surgical resection and postoperative chemotherapy. Of the 80 N-DLBCL patients, 39 (48.8%) patients were male, the median age was 64 years (range, 23-85 years), 60 (75.0%) patients were categorized into Ann-arbor stage III-IV, and 43 (53.8%) patients had high level of IPI scores (IPI score >3).
Infections were observed in 80 (61.1%) patients with DLBCL, including 28 patients with GI-DLBCL and 52 patients with N-DLBCL. The sites of infection were showed in Table 2. The most common sites of infection were respiratory tract (63.8%), followed by blood stream infection (12.5%).
The univariate analysis of 131 DLBCL patients.
In the univariate analysis, Ann-arbor stage (P<0.001), IPI scores (P=0.027), some laboratory blood examination parameters at diagnosis including CRP and hemoglobin (P=0.003 and 0.006), and some pre-infected laboratory indicators from blood biochemical examination before infection including the levels of CRP (P=0.011), erythrocyte (P=0.033), hemoglobin (P=0.004), NLR (P=0.021), platelet (P=0.015) and total bilirubin (P=0.001) were statistically significant factors associating with infection in follow up. (Table 3)
Independent risk factors of infectious events in 131 DLBCL patients
Factors which significant predictors of infection in the multivariable analysis included Ann-arbor stage III (P: 0.008; OR: 11.991; 95% CI: 1.938-74.183) and IV (P: < 0.001; OR: 64.163; 95% CI: 7.636-539.136). Patients with DLBCL who had high LDH level at the time of diagnosis (LDH ≥252 U/L) had a higher risk of infection, as compared with patients with LDH <252 U/L (P: 0.015; OR: 3.106; 95% CI: 1.241-7.773). (Table 4)
The univariate analysis of GI-DLBCL patients.
The univariate analysis of risk factors for infection in GI-DLBCL patients were summarized in Table 5. Among the 51 patients with GI-DLBCL, 28 (54.9%) patients experienced infection during treatment. Variables associated with the development of infection during treatment in this study were Ann-arbor stage (P=0.016), IPI scores (P = 0.022), the levels of LDH at diagnosis (P=0.013) and pre-infected white blood cell (WBC) (P=0.025), pre-infected neutrophils (P=0.025) and pre-infected neutrophil/lymphocyte ratio (NLR) (P=0.034). However, surgical treatment was not a risk factor as no statistically significant differences were observed between infected and non-infected groups (P >0.05) (Table 5).
The multivariate logistic regression analysis of risk factors for developing infection in GI-DLBCL patients.
The multivariate logistic regression method was used to further study the risk factors for infection in GI-DLBCL patients. The results were detailed in Table 6. Ann-arbor stage IV (P: 0.046; OR: 22.867; 95% CI: 1.053-496.508) and high LDH level at the time of diagnosis (LDH ≥252U/L; P: 0.036; OR: 1.110; 95% CI: 1.105-21.456) were identified as independent risk factors for infection in the GI-DLBCL group.
The univariate analysis of N-DLBCL patients.
The univariate analysis of possible risk factors for infection was also conducted in patients with N-DLBCL and present in Table 7. 52 of the 80 (65%) patients with N-DLBCL developed infection during treatment. Ann-arbor staging (P < 0.01), IPI scores (P = 0.005) and some pre-infected laboratory indicators including total bilirubin (P=0.001), NLR (P=0.021), erythrocyte (P=0.013) and platelets (P=0.015) were statistical different between infected group and non-infected group. Moreover, hemoglobin (Hb) and C-reactive protein (CRP) whether at diagnosis or before infection were significantly different between the infected group and the non-infected group in N-DLBCL patients (P < 0.05).
The multivariate logistic regression analysis of risk factors for developing infection in N-DLBCL patients.
Multivariate logistic regression analysis of N-DLBCL patients was carried out and detailed in Table 8. Low level of Hb at diagnosis (P: 0.037; OR: 0.970; 95%CI: 0.943-0.998), elevated pre-infected CRP (P: 0.046; OR: 4.869; 95%CI: 1.020-1.209) and pre-infected platelet (P: 0.016; OR: 0.991; 95%CI: 0.982-1.000) were observed as independent risk factors for infection in N-DLBCL patients.