Development of a new reagent for endoscopic ultrasound-guided celiac plexus neurolysis and tumor ablation therapy

BACKGROUND: Both endoscopic ultrasound-guided celiac plexus neurolysis (EUS-CPN) and tumor ablation using ethanol are very common procedures, and the utility of these therapies has already been reported in prominent journals. However, their effectiveness appears temporary and insufficient, especially EUS-CPN. We therefore have to consider new reagents for improving the results. The present study examined the best concentration of ethanol and povidone iodine mixed with atelocollagen for more effective therapies. METHODS: The effects of the new reagents were confirmed in three live pigs. At first, we injected three kinds of reagents (including indigo carmine) in three separate areas of para-aortic tissue under EUS guidance in one pig. At more than 4 hours after injection, we checked ethanol injection sites after dissection. In next study, we performed EUS-guided injection of a total of six kinds of reagents (two kinds of ethanol, three kinds of povidone iodine, and control atelocollagen) into the livers of two living pigs. After 2 weeks, we examined tissue damage to the liver in the two pigs. RESULTS: The 75% ethanol (absolute ethanol 3.75 mL + 1% atelocollagen 1.25 mL + a very small amount of indigo carmine) was seen like blue gel, and still remained in the para-aortic tissue. Brownish areas of povidone iodine mixed with 3% atelocollagen exhibited clear, regular borders with greatly reduced infiltration into surrounding tissue compared to others. CONCLUSION: We concluded that 75% ethanol mixed with 1% atelocollagen appears optimal for EUS-CPN. Povidone iodine mixed with 3% atelocollagen may be suitable for small tumor ablation therapy.

A Case of Pancreatic Cancer and Opioid Withdrawal after Endoscopic Ultrasound-guided Celiac Plexus Neurolysis / 대한소화기내시경학회지

Pancreatic cancer is usually unresectable upon diagnosis, and treatment aims to optimize the quality of the patient's life by managing symptoms, and, particularly, by providing adequate pain control. When the pain is refractory to opioids, interventions such as celiac plexus neurolysis (CPN) can be considered. Endoscopic ultrasound (EUS)-guided CPN has been introduced for pancreatic cancer. Reported herein is a case of a 75 year-old man with pancreatic cancer who was treated with opioids due to severe abdominal pain. EUS-guided CPN was performed for pain control, and the opioid administration was discontinued as the pain improved dramatically. However, the patient experienced opioid withdrawal symptoms, including anxiety, insomnia, nausea, and vomiting. Thus, although EUS-guided CPN successfully reduced pain in a patient undergoing such treatment and to whom opioid was administered, opioid administration should not be abruptly discontinued. Rather, the opioid dose should be reduced gradually to avoid drug withdrawal.