Introduction

Refractory pain management is a tough challenge for Pain Therapist. Refractory pain is defined as a persistent pain despite proper therapies associated with absence of quality life improvement and non-tolerable side effects. (1) It represents a serious condition in one-third of advanced cancer patients. 

Intrathecal drugs (e.g. morphine, ziconotide) delivery (IDD) produces valid reduction in pain intensity and side effects (nausea, drowsiness) in patients unresponsive to systemic pain therapies.

An evaluation of cancer staging, prognosis and pre-procedural imaging is mandatory before an IDD device implantation. Life expectancy less than three months is generally a contraindication. (2)

Clinical case discussion

We report the case of a 50-year-old patient with breast cancer and bone metastasis, undergoing mastectomy and multiple hormone, chemo and radiotherapy treatments over the past 8 years.

Lumbar pain associated with legs paresthesia, due to a L5 bone metastasis, was surgical treated with L5S1 laminectomy in 2020. In 2021, the somas of D11 and L1 collapsed and surgical procedure was needed for a fracture of the right hemipelvis in presence of an enhancing metastatic lesion.

Lumbar and sacral pain, exacerbated by movements and orthostatic position, was severe and disabling. Several opioid therapies, at high doses and with various routes of administration were tried (oxycodone, transdermal fentanyl, hydromorphone, methadone) but with little or no pain relief.

Even intravenous oxycodone infusion at 400 mg/day, with i.v. bolus 80 mg three times a day, (especially for painful mobilization), gave a modest pain relief while it was associated with intense daytime sleepiness. Therefore, indication to IDD was given and a test, by intrathecal morphine administration at a dosage of 0.25 mg, was performed. After an hour, complete pain relief occurred, lasting for 20 hours, without the need for rescue doses with i.v. morphine. The following day, subarachnoid catheter and a Synchromed II type pump (Medtronic®) were implanted. No side effects appeared in the subsequent days, except for a moderate 48 hours headache.

The daily dosage of intrathecal morphine was maintained for approximately 45 days at 1.5 mg/day, without need for additional analgesics; in the next 8 months oral morphine adjunctions (40 mg every 6 hours) were needed, so progressive increase of the daily dosage was necessary, up to 3,2 mg/die.

Conclusion

This case shows how the intrathecal administration of analgesic drugs is a valid option in treatment of refractory cancer pain. New devices and technologies development makes possible to deliver the most patient-centered treatment.

 Before an IDD implant, proper clinical and social patient evaluations are mandatory; interdisciplinary (pain therapist, nurse, psychologist) approach to the patient, capable of managing the implant, drug delivery and complications also appears important for the success of this kind of therapy.

Bibliography

1. A Definition of Refractory Pain to Help Determine Suitability for Device Implantation. Deer, T.R., Caraway, D.L. and Wallace, M.S. 2014), Neuromodulation: Technology at the Neural Interface, Vol. 17, p. 711-715.

2. The Polyanalgesic Consensus Conference (PACC): Recommendations for trialing of intrathecal drug delivery infusion therapy. Deer TR, Hayek S, Pope JE, et al. 2017, Neuromodulation, Vol. 20(2), p. 133–54