A Case of Complete Response to Computed Tomography-Guided Celiac Plexus Neurolysis of Pain Associated with Postoperative Recurrence of Colon Cancer

The patient was a man in his 40s, who had undergone laparoscopic ileocecal resection with lymph node dissection(D3)for cecal cancer in January 2012. Histopathological examination of the resected specimens had revealed StageⅡ primary tumor with subserosal invasion and positive metastasis in 1-3 regional lymph nodes(pT2[SS]n1[+]). The pathological stage was Ⅲa(fStage Ⅲa), and the tumor showed RAS gene mutation. The patient was administered 5 cycles of postoperative adjuvant chemotherapy with oral tegafur/uracil(UFT)in combination with calcium folinate(UZEL). Abdominal computed tomography( CT)performed 1.5 years postoperatively revealed liver metastasis, and a laparoscopic partial hepatectomy was performed in August 2015. In addition, a node in the greater omentum, located in the inferior surface of the liver, was also resected. Histopathological examination of the resected specimens revealed peritoneal metastasis, based on the identification of the same type of adenocarcinoma as the colon cancer. The patient was given 8 cycles of adjuvant chemotherapy with capecitabine and oxaliplatin(CapeOX). Then, he presented with colonic ileus, caused by recurrent dissemination, and underwent a laparoscopic transverse colectomy in October 2015. Multiple perineal disseminations were found intraoperatively, and chemotherapy was initiated with irinotecan plus tegafur/gimeracil/oteracil(S-1)plus bevacizumab(IRIS/BV)for the recurrent and unresectable disease. After 27 cycles of this regimen, lung metastasis was detected; in addition, progression of the para-aortic node metastasis around the celiac plexus was also observed, and the patient was considered as having pro- gressive disease(PD). Treatment with trifluridine/tipiracil(TAS102)was started in September 2017. Prior to the initiation of this regimen, the dose of opioid rescue medication previously started for back and abdominal pain was rapidly increased. Accordingly, the base dose was increased, but the pain could not be controlled, and the major pain was consistently located along the area of innervation in the celiac plexus. Therefore, celiac plexus neurolysis(CPN)was performed as a local therapy. A CT-guided injection technique was used to administer urografin, bupivacaine, and absolute ethanol to complete the procedure. The patient was discharged without major complications, and the base opioid dose was gradually reduced. Since the patient did not require any rescue medication during daytime on some days, the reduction of the base opioid dose was significantly effective in improving the patient's quality of life(QOL). In patients with pain possibly caused by metastasis to the para-aortic nodes, this local therapy technique may be considered.