Prognostic value of serum interleukin-6 in diffuse large-cell lymphoma.
BACKGROUND
Interleukin-6 has important lymphoid bioregulatory effects, and serum levels of interleukin-6 are often elevated in patients with lymphoma.


OBJECTIVE
To determine the relation between serum levels of interleukin-6 before treatment and outcome in patients with diffuse large-cell lymphoma.


METHODS
Retrospective cohort analysis with multivariate analysis.


METHODS
Tertiary referral center.


METHODS
118 untreated patients with diffuse large-cell lymphoma who were enrolled in frontline chemotherapy protocols and 45 healthy controls.


METHODS
Serum levels of interleukin-6 were measured by using a sensitive enzyme-linked immunosorbent assay. Levels below the upper limit of the range for controls were considered normal. Outcomes were complete response, failure-free survival, and overall survival.


RESULTS
Serum levels of interleukin-6 were higher in patients with lymphoma (median, 4.6 pg/ml [range, undetectable to 224 pg/mL]) than in controls (median, undetectable [range, undetectable to 4.3 pg/mL]) (P = 0.009). The complete response rate was 95% for persons with normal interleukin-6 levels and 55% for persons with high interleukin-6 levels (P = 0.001). Patients with high interleukin-6 levels had inferior failure-free and overall survival rates (P < 0.001 for both comparisons). The actuarial 4-year failure-free and overall survival rates were 72% and 85%, respectively, for persons with normal interleukin-6 levels and 37% and 46%, respectively, for persons with high interleukin-6 levels. In multivariate analysis, interleukin-6 was selected as the most significant predictor of complete response and failure-free survival. Failure-free and overall survival of patients stratified according to International Prognostic Index score could be further stratified by interleukin-6 level (P < or = 0.03 for all comparisons).


CONCLUSIONS
In patients with diffuse large-cell lymphoma, serum interleukin-6 levels are an independent prognostic factor for complete response and failure-free survival.
Preti
H A
HA
University of Texas M.D. Anderson Cancer Center, Houston, USA.
Cabanillas
F
F
Talpaz
M
M
Tucker
S L
SL
Seymour
J F
JF
Kurzrock
R
R
D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D018572:Disease-Free Survival; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D015850:Interleukin-6 / Q000097:blood*; D016403:Lymphoma, Large B-Cell, Diffuse / Q000097:blood* / Q000188:drug therapy / Q000401:mortality; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D012189:Retrospective Studies; D015996:Survival Rate; D016896:Treatment Outcome
D015850:Interleukin-6