Individualized use of methadone and opioid rotation in the comprehensive management of cancer pain associated with poor prognostic indicators.

This case report describes a patient affected by a neuropathic pain syndrome, which was secondary to a renal cell carcinoma metastatic to the spine, and complicated by incidental components and somatization. Due to a rapid development of tolerance and toxicity from hydromorphone, a rotation to methadone was made, with a decrease of the morphine equivalent daily dose (MEDD) from 1050 to 36. After 4 mos of good pain relief, a switch over back to hydromorphone was necessary due to worsening pain, associated with myoclonus and sedation secondary to methadone; the MEDD this time escalated from 480 to 4950. The use of hydromorphone was complicated by the onset of intractable nausea and sedation. After 2 wks, the patient was rotated again to methadone, with a decrease of the MEDD to 24. He achieved good pain control and was free of opioid toxicity. Our findings illustrate a role of methadone in the management of cancer pain associated with poor prognostic indicators, the development of tolerance towards its effects, and the regaining of sensitivity to methadone, by temporary rotation to another opioid. Possible mechanism for opioid tolerance and its reversal are discussed.