Objective: To describe the clinical characteristics, overall survival as well as to evaluate the prognostic factors in Chinese diffuse large B cell lymphoma (DLBCL) patients.
Methods: DLBCL patients who were initially diagnosed and treated in Peking University Cancer Hospital from January 1995 to December 2008 were identified and analyzed,retrospectively.The 5-year OS rates were estimated with Kaplan-Meier. Log-rank test was used to compare the survival curves of the different groups. The multivariate analysis of prognostic factors was conducted with Cox regression model, which included all statistically significant prognostic factors in the univariate analyses.
Results: A total of 525 DLBCL patients were included in this retrospective analysis, of whom, 294 were male and 231 female (male:female=1.27:1). The median age at the initial diagnosis was 55 (range 16-90) years, and 37.0% (n=194) were 60 years and above. Regarding the clinical staging at the initial diagnosis, 54 patients (10.3%) were diagnosed as Stage I of the disease, 152 (28.9%) as Stage II, 117 (22.3%) as Stage III and 202 (38.5%) as Stage IV. The "B symptoms" and increased serum LDH were presented in 206 (39.2%) and 192 (36.6%) patients, respectively. A total of 197 (37.5%) patients were treated with rituximab (R). The survival follow-up continued till 31 January 2014 with a median follow-up time of 77.5 (range: 0-205) months. A total of 267 patients (50.9%) died during the follow-up period. The medial overall survival (OS) time was 84 months, and 5-year OS rate was 52.3%. There were six statistically significant prognostic factors that were identified in both univariate and multivariate analyses: gender, Ann Arbor stage, B symptom, serum LDH, age at initial diagnosis and rituximab treatment. The relative risk (RR) of these prognostic factors in the multivariate analyses were: age > 60 years / ≤ 60 years=1.380 (95%CI 1.078-1.765), male / female=1.315 (95%CI 1.025-1.687), stage III/stage I=3.034 (95%CI 1.667-5.522), stage IV/I=3.748(95%CI 2.102-6.681), with B symptoms/without B symptoms=1.278(95%CI 0.999-1.636), serum LDH increased/LDH not increased=1.351(95%CI 1.057-1.726), without R treatment / with R treatment=1.543 (95%CI 1.182-2.015).Compared with the IPI, age >50 years/ ≤ 50 years was a statistically significant factor in both univariate and multivariate analyses RR=1.478 (95%CI 1.148-1.902), P=0.002.
Conclusion: Six factors were related to DLBCL survival: gender, Ann Arbor stage, B symptom, serum LDH, age at initial diagnosis and rituximab treatment. Compared with the IPI, several specific factors may predict a poor prognosis in Chinese DLBCL patients: male, age>50 years and the presence of "B symptoms". But this result is not conclusive until these factors are further tested.