Endovascular denervation can improve pain in patients with abdominal cancer and may offer a new approach to palliative care, according to a study recently published in the Journal of Vascular and Interventional Radiology. The study investigators, Qi Zhang, Gao-Jun Teng (both Center of Interventional Radiology and Vascular Surgery, Zhongda Hospital, Nanjing, China) and colleagues, conclude that the procedure is safe and effective for the alleviation of pain caused by cancer.
The study enrolled seven patients (two men and five women) with diagnoses including pancreatic cancer (n=3), cervical carcinoma (n=2), cholangiocarcinoma (n=1), and oesophageal cancer with retroperitoneum lymph nodes invasion (n=1) from April 2017 to February 2018.
A surface electrode was placed on the back of each patient and connected to the denervation device. Denervation was carried out at the abdominal aorta close to the origin of celiac artery and superior mesenteric artery with the use of a multi-electrode radiofrequency ablation catheter with the time and temperature settings respectively at 120 seconds and 60°C.
The authors report that all patients experienced pain relief after treatment, meeting the primary endpoint of improvement in pain score. At one, two, four, eight, and 12 weeks after the procedure pain scores, measured by visual analogue score, decreased significantly compared with baseline (p<0.001). All patients experienced a greater than four-point score reduction.
Secondary endpoints included changes in quality of life, intake of narcotics, and the safety of endovascular denervation.
Narcotics use was significantly reduced within the first three months after treatment, and quality of life scores were improved significantly (p<0.005) with better sleep. There were no severe treatment-related adverse events or major complications reported.
Speaking to Interventional News of how these results will influence clinical practice, corresponding author Gao-Jun Teng, president of the Zhongda Hospital, Southeast University, Nanjing, China, says “Our report presented the preliminary results in a small number of patients, but it showed very promising and encouraging results. It will certainly inspire further research using endovascular denervation. I would not be surprised to see endovascular denervation become a useful tool in pain management in the very near future.”
Writing in the Journal of Vascular and Interventional Radiology, the authors conclude: “Cancer pain management is a formidable problem for physicians and may result in a substantial burden to the public health care system. Opioid analgesics are often required to control cancer pain. Adverse effects from opioids are debilitating and worsen as larger doses are administered,” the authors write. “This preliminary trial demonstrated that endovascular denervation is a promising and safe method for the palliation of pain caused by abdominal cancers. It could be a new approach for management of cancer pain.”
A new approach to palliative care
“This may give interventional radiologists a brand-new approach to treating pain”, Teng adds, “thus [acting to] solidify their place in the field of pain management. Endovascular denervation provides interventional radiologists a new and big territory for treating non-hypertension diseases, which has previously been considered a procedure performed by cardiologists.”
Teng believes it is important to find a new approach to palliative care, telling this newspaper: “It is well known that cancer pain has significant impacts on patients’ quality of life, as well as their prognosis. Traditional management uses narcotics, sometimes in large quantities, which often result in severe side effects such as impairment of judgement and respiratory suppression. Interventional neurolysis under CT/US [computed tomography/ultrasound] is a traditional interventional radiology procedure, which involves the deep puncture of a needle and injects chemical (alcohol, phenol) agents. Accurate needle localisation may be a challenge for inexperienced interventional radiologists. The outcomes vary from the operator’s skill, and the degree of diffusion of the neurolytic agents is sometimes out of control, which may cause serious complications.
“New approaches—especially nonopioid methods—in pain management are still in need clinically. Due to the ubiquitous nature of the vascular network and anatomical accompany of nerves and arteries, endovascular denervation could be a great approach in pain management. It has the advantages of being minimally invasive, [enabling] easy access to any part of the body, and having fewer side effects.”
However, Teng also states that the mechanism for endovascular denervation on uncontrollable cancer pain is “still unclear”, and that more work is required to elucidate the procedure’s machinations. He is the principal investigator in a large scale clinical trial currently ongoing in China and involving more than 10 national medical centres. Speaking of this trial, and what it means for the future of endovascular denervation, he says: “We are exploring different ablation sites for controlling cancer pain in other parts of the body. We are also working to expand the application of the technique to manage pain caused by other diseases.”