Safety and Efficacy of Surgical Implantation of Intrathecal Drug Delivery Pumps in Cancer Patients with Refractory Pain

Introduction: Pain management in cancer patients is a critical issue in oncology palliative care, as clinicians aim to enhance quality of life and mitigate suffering. Most cancer patients experience cancer-related pain, though pain control is oftentimes inadequate, with 30-40% of cancer patients experiencing intractable pain despite maximal medical therapy. Intrathecal pain pumps (ITPs) have emerged as an option for achieving pain control in patients with refractory cancer pain. Due to the potential benefits of ITPs in cancer-related pain, we sought to study the long-term outcomes of this form of pain management in a tertiary cancer center.

Methods: We retrospectively reviewed medical records of all adult cancer patients who underwent ITP placement at a tertiary comprehensive cancer center between 2016 and 2021. Baseline characteristics, pre- and postoperative pain control, and postoperative complication rate data were collected.

Results: A total of 193 patients were included with an average follow-up time of 10 months. We found that the average numerical rating scale (NRS) score decreased significantly by 4.08 points (SD = 2.13, p < 0.01), from a pre-operative NRS of 7.38 (SD = 1.64) to 3.27 (SD 1.66). Of 189 patients with follow-up (NRS) pain scores, 176 (93.1%) experienced a decrease in NRS and two (1.0%) patients had an increase in NRS. Mean overall survival from time of pump placement was 3.62 months (95% confidence interval 2.73-4.54). A total of 43 adverse events were reported during the study period. The most common complications were pneumonia (6), urinary tract infection (6), surgical site infection (5), and deep venous thrombosis (4). Twelve (6.2%) patients required re-operation during the study period. Only one patient experienced meningitis.

Conclusion : Our study demonstrates that ITP implantation for the treatment of cancer-related pain is a safe and effective method of pain palliation with a low complication rate in a medically complex patient population. While there was a significant rate of mortality within three months of pump placement, this may be ameliorated by earlier referral for ITP placement evaluation.