Pulmonary embolism: a fatal complication of arterial chemoembolization for advanced hepatocellular carcinoma

Pulmonary complications of transcatheter arterial chemoembolization for hepatocellular carcinoma

Transcatheter arterial chemoembolization (TACE) is an effective palliative intervention that is widely accepted for the management of hepatocellular carcinoma (HCC). Post-TACE pulmonary complications resulting in acute lung injury (ALI) or acute respiratory distress syndrome (ARDS) are rare events. Pulmonary complications after TACE are thought to be related to chemical injury subsequent to the migration of the infused ethiodized oil or chemotherapeutic agent to the lung vasculature, facilitated by arteriovenous (AV) shunts within the hyper-vascular HCC. We review herein the literature on pulmonary complications related to TACE for HCC. Post-TACE pulmonary complications have included pulmonary oil embolism, interstitial pneumonitis, chemical pneumonitis, ALI, ARDS, lipoid pneumonia, acute eosinophilic and neutrophilic pneumonia, bilious pleuritis, pulmonary abscess, pulmonary tumor embolism, and possibly pulmonary metastasis with HCC. The risk factors associated with post-TACE pulmonary complications identified in the literature include large hyper-vascular HCC with AV shunts, large-volume Lipiodol infusion, and embolization via the right inferior phrenic artery. However, the absence of known risk factors is not a guarantee against serious complications. An astute awareness of the potential post-TACE pulmonary complications should expedite appropriate therapeutic interventions and increase potential for early recovery.

Risk factors for the development of pulmonary oil embolism after transcatheter arterial chemoembolization of hepatic tumors

Pulmonary oil embolism (POE) is a rare fatal complication after transcatheter arterial embolization (TAE) and transcatheter arterial chemoembolization (TACE). As risk factors have not been clearly delineated, the aim of the present study was to identify the risk factors for development of POE after TACE. A retrospective analysis was carried out on patients with unresectable hepatocellular carcinoma who received TAE or TACE at the Tri-Service General Hospital (Taiwan) between January 2005 and December 2008. The diagnosis of TAE-induced or TACE-induced POE was based on development of respiratory signs and symptoms relatively soon after the procedure, as well as based on characteristic radiographic findings. Of the 219 enrolled patients in this study, 20 were diagnosed with POE after TAE or TACE. On univariate logistic regression analysis, patients developing POE were found to be older (67.95±15.95 vs. 61.44±12.59 years, P=0.033), with a lower serum albumin level (3.25±0.58 vs. 3.62±0.57 g/dl, P=0.009), a higher grade of liver cirrhosis as classified on the basis of Child's criteria (P<0.006), a larger tumor size (8.55±4.52 vs. 4.78±3.97 cm in diameter, P<0.001), a higher lipioidol dose (22.35±11.01 vs. 13.69±7.66 ml, P=0.003), and a higher doxorubicin dose (50.27±7.05 vs. 40.75±13.61 mg, P<0.001). Following multivariate logistic regression analysis, only lipiodol dose was found to be a significant risk factor for POE (odds ratio=1.133, 95% confidence interval: 1.004, 1.279; P=0.044). The receiver operator characteristic curve cutoff point for lipiodol dose level was 14.5 ml, with a sensitivity of 80% and a specificity of 66.3%. In conclusion, the lipiodol dose could be considered as a predictive factor for POE after TAE or TACE in hepatic malignant tumor patients. On the basis of this retrospective study, the safe lipiodol dose to minimize the risk for POE is 14.5 ml or lower; however, larger, prospective studies are needed to determine the optimally safe and yet efficacious dose.

Pulmonary embolism after arterial chemoembolization for hepatocellular carcinoma: An autopsy case report

We report an extremely rare case of pulmonary lipiodol embolism with acute respiratory distress syndrome (ARDS) after transcatheter arterial chemoembolization (TACE) for hepatocellular carcinoma (HCC). A 77-year-old man who was diagnosed with a huge HCC was admitted for TACE. Immediately after the procedure, this patient experienced severe dyspnea. We suspected that his symptoms were associated with a pulmonary lipiodol embolism after TACE, and we began intensive treatment. However, his condition did not improve, and he died on the following day. A subsequent autopsy revealed that the cause of death was ARDS due to pulmonary lipiodol embolism. No cases have been previously reported for which an autopsy was performed to explain the most probable mechanism of pulmonary lipiodol embolism; thus, ours is the first report for such a rare case.

Multidetector computed tomography findings of dense pulmonary emboli in oncologic patients

Pulmonary embolism is a frequent condition for which multidetector computed tomography (MDCT) plays an important role in its detection. Occasionally, on MDCT studies, dense linear branching opacities may be found within the pulmonary vessels. They represent dense emboli within the pulmonary arteries (DEPA). These may occur in oncologic patients that undergo specific treatments or interventional procedures, such as cement embolus from vertebroplasty, catheter or coil migration after embolization procedures, radioactive seed embolus in patients treated with local brachytherapy for prostate, lung, or liver cancer, and also in chronic pulmonary embolism. Usually DEPA does not have any clinical significance but may be fatal when massive or when in patients with impaired cardiopulmonary function. Being familiar with their radiologic appearance and knowing about the good clinical outcome of these patients will avoid unnecessary imaging testing. In this article, we describe some examples of DEPA. Based on the MDCT imaging findings, these emboli have very few or no side effects on the underlying lung parenchyma. We would like to stress the need for using bone window values for identifying these emboli. We provide examples of dense linear nonvascular images (pulmonary calcification secondary to tuberculosis (TBC) or radiotherapy, calcified mucous plugs, lung sutures, etc) that may mimic DEPA.

Acute respiratory distress syndrome after transcatheter arterial chemoembolization of hepatocellular carcinomas

BACKGROUND

Acute respiratory distress syndrome (ARDS) associated with pulmonary lipiodol embolism is a rare complication of transcatheter arterial chemoembolization (TACE). We performed a survey of ARDS associated with pulmonary lipiodol embolism after TACE.

METHODS

A retrospective analysis of the cases of all patients with hepatic tumors who received transcatheter arterial embolization or TACE between January 2006 and December 2006 was performed. The diagnosis of pulmonary lipiodol embolism was confirmed by chest computed tomography (CT).

RESULTS

The diagnosis of ARDS associated with pulmonary lipiodol embolism was confirmed in 4 patients. All had large (> or =5 cm) and hypervascular tumors. There was no evidence of hepatocellular carcinoma arteriovenous shunting in any of our patients as determined by angiography and multidetector CT. The volumes of lipiodol infused in the 4 patients were 50, 20, 30, and 20 mL. Only 2 patients received injections of carcinostatic agents. The onset of respiratory symptoms occurred between 1 hour and 4 days after TACE. Respiratory symptoms consisted of dyspnea and tachypnea. Chest CT scans revealed linear high-density shadows, suggestive of lipiodol retention in both lungs of all patients.

CONCLUSION

Pulmonary lipiodol embolism after TACE can occur within a short time frame. Whether or not there is intrahepatic arteriovenous shunting detected by multidetector CT and angiography, clinicians should avoid high doses of iodized oil and carcinostatic agents. We suggest that CT should be used for the diagnosis of pulmonary lipiodol embolism.

Use of angioembolization as an effective technique for the management of pediatric solid tumors

PURPOSE

In oncology practice, angioembolization has been reported for tumor reduction before surgery, treatment of life-threatening conditions, and for palliative care. Nevertheless, the overall experience with angioembolization for the treatment of tumors is limited. We report our experience in 7 nonvascular solid pediatric tumors.

MATERIALS AND METHODS

A retrospective review was carried out of medical records from pediatric patients (0-18 years) with solid nonvascular tumors who underwent angioembolization in the last 5 years at our institution.

RESULTS

Seven patients underwent embolization: 2 neuroblastomas, 1 metastatic paraganglioma, 1 hepatoblastoma, 1 myofibroblastic tumor, 1 osteosarcoma, and 1 undifferentiated sarcoma. The reason for angioembolization was preparation for surgery (3), treatment of a life-threatening event (1), or palliative care (3). Each case is presented and discussed. The outcome was subsequent complete surgical resection in 3 cases, tumor vanished in 1 case, symptom control was achieved in 1, and the other 2 patients improved their survival and quality of life, however, died of disease progression.

CONCLUSIONS

Tumor angioembolization may enter the treatment algorithm for selected patients who have to face difficult or unwarranted surgical procedures or have diseases where conventional therapies have failed.

TACE versus TAE as therapy for hepatocellular carcinoma

Transarterial chemoembolization (TACE) improves survival in cirrhotic patients with hepatocellular carcinoma (HCC). The optimal schedule, best anticancer agent and best technique are still unclear. TACE may not be better than transarterial embolization (TAE). HCC is very chemoresistant, thus embolization may be more important than chemotherapy. Lipiodol cannot be considered as an embolic agent and there are no data to show that it can release chemotherapeutic agents slowly. It can mask residual vascularity on CT imaging and its use is not recommended. Both TACE and TAE result in hypoxia, which stimulates angiogenesis, promoting tumor growth; thus combination of TACE with antiangiogenic agents may improve current results. To date, there is no evidence that TACE pre-liver transplantation or resection helps to expand current selection criteria for patients with HCC, nor results in less recurrence after surgery. Combination with other techniques, such as radiofrequency ablation and drugs, may enhance the effect of TACE. New trials are being conducted to clarify these issues.