Alleviation of Pain in Cancer Patients by Adrenal Medullary Transplants in the Spinal Subarachnoid Space

Abstract

The treatment of intractable pain with currently available therapeutic regimens is often unsatisfactory due to tolerance and untoward complications. Studies in our laboratory have suggested that the transplantation of adrenal medullary tissue into the spinal subarachnoid space can significantly reduce pain in animal models, most likely via release of opioid peptides and catecholamines. The current study was an initial attempt to assess the potential for adrenal medullary transplants in the spinal subarachnoid space to alleviate pain in humans. Donor adrenal medullary tissue was prepared for transplantation in our laboratory. One cc of adrenal medullary tissue was transplanted via lumbar puncture in five patients suffering from terminal cancer pain. Pain levels were determined using a Visual Analog Pain Scale prior to and following the transplantation procedure. In addition, records of narcotic intake and activity were kept. When possible, CSF samples were collected via lumbar puncture for biochemical and cytological analysis. Four of the patients demonstrated progressive decreases in pain scores following the procedure, with concomitant reductions in narcotic intake. Three patients remained pain free, two for over 10 mo. One patient, who developed spinal cord compression secondary to metastasis, was initially pain free, but the pain returned after 10 wk. The fifth patient had no pain reduction by 1 mo following the procedure, but further information was unavailable due to poor patient compliance. In most cases, spinal cerebrospinal fluid (CSF) samples revealed increased levels of met-enkephalin and/or catecholamines following the transplants. The results of this study suggest that adrenal medullary transplants in the spinal subarachnoid space have potential as an alternative approach to the management of chronic pain in humans.