Application of intraluminal brachytherapy for malignant obstruction in the porta hepatis: a retrospective control study

Abstract

Purpose and background: Malignant obstructions in the porta hepatis mainly include malignant obstructive jaundice (MOJ) and portal vein tumor thrombus (PVTT). Stent placement has been one of the most commonly recommended methods to alleviate the physical suffering of these patients, but the long-term outcome has been frustrating in terms of stent occlusion. The aim of this study was to discuss the clinical effect and technical feasibility of intraluminal brachytherapy (ILBT) in patients with malignant obstruction in the porta hepatis.

Methods and materials: From 2016 to 2018, 68 patients diagnosed with malignant obstruction in the porta hepatis were retrospectively included in this study. Twenty-eight patients (group A) received stent placement with iodine-125 seed-strand implantation, and 40 patients (group B) received stent placement only. All patients underwent numerous transarterial chemoembolizations (TACE) after stent implantation. All patients were followed up until death. Clinical data, stent patency and survival time were recorded for further analysis.

Results: There was no significant difference between the two groups in terms of length of malignant obstruction and baseline characteristics. 68 stents were successfully implanted in both groups.Iodine-125 seed strands were successfully deployed and completely covered the length of the stent in group A. Liver function and jaundice improved continuously in the first 9 months after treatment (P<0.05). Compared to group B, the mean stent patency time was significantly longer in group A (5.5 ± 2.09 months versus 6.86 ± 1.82 months, P<0.001). The mean survival time is longer in group A than in patients in group B (10.03 ± 3.04 months VS 7 ± 2.44 months, P<0.001).

Conclusion: ILBT in combination with stent implantation and TACE has proven to be a feasible and effective palliative treatment to maintain stent patency in patients with PVTT and MOJ.

Keywords: iodine-125 seed strands; malignant obstructive jaundice; portal vein tumor thrombus; stent placement; transarterial chemoembolization (TACE).

Figure 1

Patient with MOJ. (A) Cholangiogram showing dilatation of the intrahepatic bile ducts and the initial common bile duct and severe stenosis of the common bile duct. (B) Two 0.018-inch hydrophilic guidewires and a stiff wire were carefully advanced through the stenotic segment into the distal duodenum. (C) After stent placement, two 0.018-inch wires were left outside the stent to introduce a seed strand. (D) Two seed strands were implanted over two 0.018-inch wires each.

Figure 2

A patient with PVTT. (A) Angiography of the splenic vein showed blood flow away from the liver, the direction corresponding to the arrow. (B) The obstruction was located at the main portal boot (arrow). (C) After implantation of a self-expandable stent and an iodine-125 seed string under DSA, the seeds moved in the tube as the patient’s position changed, causing internal irradiation of normal tissue (arrow). (D) Finally, portal venography showed patency of the stent.

Figure 3

(A, B) In group A, there were significant differences in GPT and TBIL between baseline, 3 days, 3 months and 6 months later (P<0.01, respectively). (C, D) In group B, GPT and TBIL levels 3 days later were lower than at baseline (P<0.01), while GPT and TBIL levels 6 months later were similar to baseline (P=0.07 and P=0.45, respectively). *P<0.05, **P<0.01.

Figure 4

(A) Mean stent patency time was significantly longer in group A than in group B (P=0.032); (B) Mean survival time was significantly longer in group A than in group B (P<0.001).