Intrathecal betamethasone pain relief in cancer patients with vertebral metastasis: a pilot study

Background We have reported previously the usefulness of intrathecal betamethasone for pain relief in cancer patients who suffer from intractable pain caused by vertebral metastasis. The mechanism by which betamethasone relieves pain may be related to alterations in cerebrospinal fluid (CSF) concentrations of pro-inflammatory cytokines and prostanoids. Methods Thirteen cancer patients with intractable pain caused by vertebral metastasis received 2-3 mg betamethasone in the lumbar subarachnoid space. CSF concentrations of tumor necrosis factor-alpha (TNF-alpha), interleukin-1 beta (IL-1 beta), IL-6, IL-8 and prostaglandin E-2 (PGE(2)) were measured with an enzyme-linked immunosorbent assay (ELISA) and a chemiluminescence enzyme immunoassay. Pain was measured using a numerical pain score (range, 0-10; 0, no pain; 10, worst pain imaginable). Results Intrathecal betamethasone was associated with a significant decrease in the pain score in six patients. In these cases, the pain score decreased from 6.7 +/- 0.5 (mean +/- standard error of the mean) to 3.3 +/- 0.3 (P < 0.05), and the CSF concentrations of IL-8 and PGE(2) decreased significantly compared with pre-treatment levels (IL-8, 183.3 +/- 21.2 to 116.5 +/- 10.6 pg/ml; PGE(2), 43.8 +/- 10.3 to 14.7 +/- 3.0 pg/ml). There were no significant changes in the CSF concentrations of cytokines and PGE(2) in the remaining seven patients. Conclusions Pain relief with intrathecal betamethasone is related to decreases in the CSF concentration of IL-8 and PGE(2).