Comparison of Two Seed Strand Implantation Techniques for Biliary Cancer

The First Affiliated Hospital of Anhui Medical University

Status: Completed

Conditions: Malignant Obstructive Jaundice

Treatments: Radiation: Percutaneous transhepatic biliary stenting with conventional linear ^125^I seeds strand; Radiation: Percutaneous transhepatic biliary stenting with novel spiral ^125^I seeds strand

Study type: Interventional

Funder types: Other

Identifiers

NCT07381439

LLSC20221301

Details and patient eligibility

About

This study aimed to compare the safety and effectiveness of two different methods for fabricating and implanting Iodine-125 (^125^I) radioactive seed strands combined with a metal stent for treating malignant obstructive jaundice. The conventional method uses a straight seed strand placed between the stent and the bile duct wall. A novel technique was developed that uses a spiral-shaped seed strand placed inside the stent lumen.

Between January 2018 and February 2024, 105 patients were randomly assigned to two groups. Group A (59 patients) received the conventional straight strand, while Group B (46 patients) received the novel spiral strand. The study compared therapeutic efficacy, the incidence of intraoperative and postoperative complications, stent patency duration, and patient survival.

Both methods successfully improved liver function. However, the novel spiral technique (Group B) caused significantly fewer complications, such as bile leakage and peritonitis, compared to the conventional method (Group A). Importantly, patients in Group B also had longer stent patency (305 days vs. 277 days) and longer overall survival (345 days vs. 300 days).

In conclusion, the novel spiral seed strand implantation technique is a safer and more effective treatment option for malignant obstructive jaundice.

Full description

Malignant obstructive jaundice often requires palliative drainage with self-expanding metallic stents. Combining stents with brachytherapy using Iodine-125 (^125^I) seed strands has been shown to prolong stent patency and patient survival compared to stenting alone. The conventional technique implants a linear seed strand between the stent and the bile duct wall, which is associated with risks of hemobilia, biliary fistula, and peritonitis due to the need for a larger puncture tract. This prospective, randomized controlled trial aimed to evaluate a novel, refined method involving a spiral-configured ^125^I seed strand implanted within the stent lumen, hypothesizing that it would reduce procedure-related complications while maintaining or improving therapeutic efficacy.

Study Design and Methods:

This was a single-center, prospective, randomized controlled trial. From January 2018 to February 2024, 105 patients with inoperable malignant obstructive jaundice were enrolled and randomly allocated into two groups.

Group A (Conventional, n=59): Received a straight ^125^I seed strand implanted between the metallic stent and the bile duct wall.

Group B (Novel, n=46): Received a spiral ^125^I seed strand implanted within the lumen of the metallic stent.

All patients first underwent percutaneous transhepatic biliary drainage (PTBD) for decompression, followed by the combined stent and seed strand (PTBSIS) procedure 3-7 days later.

Primary and Secondary Outcomes:

The primary endpoints were procedure-related complications (intraoperative and postoperative) and stent patency time. Secondary endpoints included technical success rate, improvement in liver function tests at one month, and overall patient survival. Complications assessed included nausea/vomiting, abdominal pain, hemobilia, vagal reflex, fever, biliary fistula, and biliary peritonitis.

Statistical Analysis:

Continuous data are presented as mean ± standard deviation or median (interquartile range). Categorical variables were compared using the Chi-square or Fisher's exact test. Stent patency and overall survival were analyzed using the Kaplan-Meier method with the log-rank test. A two-sided P-value < 0.05 was considered statistically significant. Analyses were performed using SPSS version 22.0.

Enrollment: 105 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• 1. Patients with a definitive diagnosis of Malignant Obstructive Jaundice (MOJ) confirmed by imaging (enhanced CT/MRCP), laboratory tests, and/or pathology.

  2. Assessed by a multidisciplinary team as not a candidate for curative surgical resection.

  3. No absolute contraindications for the combined implantation of a biliary metallic stent and an ^125^I seeds strand (e.g., severe coagulation dysfunction, significant renal impairment, or uncontrolled serious cardiovascular/cerebrovascular diseases).

  4. Willing and able to provide written informed consent.

Exclusion criteria

1. Obstructive jaundice attributable to benign etiology.
2. Presence of any absolute contraindication listed in the inclusion criteria.
3. Life expectancy estimated to be less than three months.
4. Unwillingness to participate in the study or provide informed consent.

Trial design

Primary purpose: Other

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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105 participants in 2 patient groups

Conventional linear implantation

Experimental group

Description:

In this group, participants received percutaneous transhepatic biliary stenting combined with a straight-configured \^125\^I seed strand. The strand was fabricated by loading the prescribed number of \^125\^I seeds into a 4F catheter, the ends of which were subsequently heat-sealed. During the procedure, after the deployment of a self-expanding metallic stent across the malignant stricture, the straight seed strand was implanted and fixed in the space between the outer wall of the stent and the bile duct wall to deliver localized brachytherapy.

Treatment:

Radiation: Percutaneous transhepatic biliary stenting with conventional linear ^125^I seeds strand

Novel spiral implantation

Experimental group

Description:

In this group, participants received percutaneous transhepatic biliary stenting combined with a spiral-configured \^125\^I seed strand. The strand was fabricated by first preparing a linear catheter strand and then shaping it into a spiral configuration using boiling water. A slightly higher number of seeds were used to compensate for foreshortening. During the procedure, after stent deployment, the spiral seed strand was implanted and secured within the inner lumen of the metallic stent. This method was designed to reduce tract-related injury by utilizing a single, smaller working sheath and minimizing manipulation of the bile duct wall.

Treatment:

Radiation: Percutaneous transhepatic biliary stenting with novel spiral ^125^I seeds strand