Evolution of low back pain in cancer patients treated with interventional pain management

Abstract

Objective: To identify the evolution of low back pain in cancer patients treated with interventional pain management. Material and methods: Descriptive and retrospective study. A search was carried out in data patients treated at Pain Clinic of the National Cancer Institute who underwent an interventional procedure for low back pain in the period from January 2017 to December 2019. The statistical analysis was performed in SPSS 15.0 program and information was presented in frequency tables. Results: 143 patients were analyzed, the highest percentage being women (69 %) with a mean age of 65 years. Most frequent risk factors identified were type 2 diabetes mellitus (18.2 %) and arterial hypertension (14.7 %). Most frequent oncological diagnoses were breast cancer (38.5 %), prostate cancer (14 %), multiple myeloma (13.3 %), and cervical cancer (10.5 %). Opioids used were tramadol (48.3 %), morphine (32.2 %), buprenorphine and tapentadol (5.6 %), oxycodone (1.4 %), fentanyl and methadone (0.7 %). Interventional approaches in greater proportion were steroid deposition in dorsal medial branch of the lumbar zygapophyseal joint of 3 segments (11.2 %), steroid deposition of dorsal medial branch of the lumbar zygapophyseal joint of 4 or more segments (7.7 %) and vertebroplasty (5.6 %), it was also observed that 60.8 % of patients received more than one interventional approach. Therapeutic response greater than or equal to 50 % was presented in 86.7 % of patients and 35.7 % showed a mean reduction in opioids of 22.2 milligrams / day. Low back pain with a neuropathic component occurred in 57.3 % of patients. According to verbal analogue scale evaluation before and a week after treatment, changes in mild pain were observed from 8.4 % to 77.6 %, moderate pain from 21.7 % to 46.9 % and severe pain from 44.8 % to 0.7 %. One month after the procedure, 70.6 % were observed for mild pain, 23.8 % moderate pain and 5.6 % severe. Evaluation of Douleur Neuropathique-4 items questionnaire before therapeutic approach, 42.7 % of patients presented a score lower than 4, while 57.3 % presented a score greater than 4. After one week percentage was 85.3 % and 14.7 % respectively, and after one month, 84.6 % of patients presented a score lower than 4. Conclusions: Steroid deposition in dorsal medial branch of the lumbar zygapophyseal joint of 3 segments, 4 or more segments and vertebroplasty were the most frequent approaches. Therapeutic response greater than or equal to 50 % was presented in 86.7 % of patients, however, due to the multiple etiology of this condition, administering different approaches in the same patient could improve lumbar pain, this was reflected in persistence of pain one month after the procedure where a significant change was observed from moderate and severe pain to mild pain (70.6 %) as well as a decrease in opioid analgesics; however, prospective studies are required to further characterize its effectiveness. The choice to perform these techniques is recommended after an individualized analysis of the patients to seek the greatest benefit and avoid complications.