Gastrointestinal tract complications after hepatic radiofrequency ablation: CT prediction for major complications.

PURPOSE: To analyze CT features that predict major gastrointestinal tract (GIT) complication after hepatic radiofrequency ablation (RFA).

MATERIALS AND METHODS: Of 3933 patients who underwent RFA for hepatic malignancy from January 2005 to September 2016, 52 patients (1.32%) who had GIT complications were retrospectively enrolled. Electronic medical records and CT results were reviewed for location (left vs. right lobe, subcapsular vs. non-subcapsular) and tumor size, distance from the hepatic capsule, number and length of needles, ablation time, presence of artificial ascites, previous history of percutaneous treatment or operation, injured organs, length and thickness of injured GIT, presence of adjacent infiltration, ascites, mucosal discontinuity, and free air, and eccentricity. Patients were divided into those that recovered with conservative treatment (minor group) and those that required operation (major group). Chi-square test, Fisher's exact test, and Mann-Whitney U test analyzed differences between the two groups; however, the most significant variable was found using binary logistic regression analysis.

RESULTS: Of 52 patients who had GIT complications after hepatic RFA, 2 patients (0.05%) had major GIT complications, while the remaining 50 patients (1.27%) had minor complications. Most (47/52, 90.4%) of the tumors were located at subcapsular portion. 66% of tumors were located at the left hepatic lobe. Stomach was the most frequent injured organ (28/52, 53.8%), followed by colon (17/52, 32.7%) and small bowel (7/52, 13.5%). Patients with major GIT complications had significantly thicker (1.8 vs. 1.1 cm) and concentric (2/2, 100% vs. 1/50, 2.0%) bowel wall thickening with mucosal discontinuity (2/2, 100% vs. 0/50, 0%) than those with minor complications (P < 0.05).

CONCLUSION: GIT complication after hepatic RFA is rare and often requires conservative treatment. However, patients who show >1.65-cm-thick, concentric bowel wall thickening with mucosal disruption on CT after hepatic RFA may have major GIT injury that requires bowel surgery.