Abstract
The method for cancer pain relief proposed by the World Health Organization consists of guidelines for a three-step treatment, from non-opioids to weak and then strong opioids. The immunomodulatory effects of opioids have been documented by numerous reports. However, little is known about how morphine may alter immune functions in terminally ill cancer patients. This study was designed to evaluate the effect of morphine on immune status as designated by the lymphocyte cluster in peripheral blood of terminally ill cancer patients.
Consecutive terminally ill cancer patients admitted to Palliative Care Center in Tohoku University Hospital from January to May 2001 were enrolled in this study. Of 61 patients who gave a written informed consent, 37 had been treated for their pain with morphine. Common serum enzyme markers were determined using standard hospital laboratory methods. Cellular immunity status was evaluated by lymphocyte-subset analysis in peripheral blood by flow cytometry.
No difference was seen in pain control between the morphine group and the control group (numerical rating score: 1.4±2.2vs. 1.2±1.9). We found significant difference in C- reactive protein (morphine group: 9.08±1.96vs. control group: 3.24±4.16, p=0.023), CD3- CD56+ cell- counts (117.5±156.1vs. 277.3±339.5, p=0.017) and CD8+ cell- counts (122.7±104.8vs. 247.0±231.0, p=0.006). Single regression analysis, however, revealed that the immune alteration of terminally ill patients was not associated with the serum concentration of morphine.
