Diaphragmatic hernia after radiofrequency ablation of liver metastases: a case report and review of the literature.

A diaphragmatic hernia is the protrusion of abdominal tissues into the thoracic cavity secondary to a defect in the diaphragm. Reviewing the literature, we found only 44 references to diaphragmatic hernia secondary to percutaneous radiofrequency treatment. The vast majority of these cases were secondary to the treatment of hepatocellular carcinoma in segments V and VIII. Nevertheless, to date, this is the first reported case of diaphragmatic hernia after radiofrequency ablation of a liver metastasis from colorectal cancer. Complications secondary to diaphragmatic hernias are very diverse. The principal risk factor for complications is the contents of the hernia; when small bowel or colon segments protrude in the thoracic cavity, they can become incarcerated. Asymptomatic cases have also been reported in which the diaphragmatic hernia was discovered during follow-up. The pathophysiological mechanism is not totally clear, but it is thought that these diaphragmatic hernias might be caused by locoregional thermal damage. Given that most communications correspond to asymptomatic and/or treated cases, it is likely that the incidence is underestimated. However, due to the advent of percutaneous treatments, this complication might be reported more often in the future. Most cases are treated with primary herniorrhaphy, done with a laparoscopic or open approach at the surgeon's discretion; no evidence supports the use of one approach over the other. Nevertheless, it seems clear that surgery is the only definitive treatment, as well as the treatment of choice if complications develop. However, in asymptomatic patients in whom a diaphragmatic hernia is discovered in follow-up imaging studies, management should probably be guided by the patient's overall condition, taking into account the potential risks of complications (contents, diameter of the opening into the thoracic cavity …).