A Novel Segmented Stent Customized with the Aid of Three-Dimensional Printing for Inoperable Malignant Airway Stenosis Involving Carina or Distal Bronchi: A Proof-of-Concept Study

Abstract

Background: Malignant airway stenosis is life-threatening and leads to a reduced quality of life. The treatment of malignant stenosis involving the carina and distal bronchi is challenging because of the complicated anatomy that is variable among individual patients, which makes it necessary to customize stents individually. Methods: The stents were individually customized with the aid of 3D printing mold according to the anatomic features of the airway in individual patients. A segmented design was applied on the junction part of the main stem and the branches to fit the dynamic changes of carina angle. 10 patients underwent insertion of such stents for dyspnea due to airway stenosis caused by malignancies including esophageal cancer and lung cancer. The technical and clinical success of stenting procedure, and Hugh-Jones (HJ) classification, Karnofsky performance status (KPS) and stent-related complications of patients were evaluated. Findings: The stenting procedures were technically successful in all patients, and 9 patients showed significant palliation of dyspnea after stenting. The HJ and KPS classification of patients after stent insertion improved significantly compared with those before stenting (P = 0.007 and P=0.015, respectively). During follow-up, granulation tissue proliferation and sputum retention were found in 2 and 3 patients, respectively. Interpretation: The implantation of the novel segmented stent is feasible for relieving dyspnea and improving performance status of patients with inoperable malignant stenosis involving the carina and distal bronchi distal. Funding Statement: Supported by the Shanghai key specialty construction project (No. ZK2019A02); Clinical key specialist construction project of Shanghai municipal health commission (Interventional Radiology & 3D Printing); Shanghai municipal commission of health and family planning (No. 201640087). Declaration of Interests: Zhongmin Wang is a co-inventor on a patent of the stent used in this study. The owner of the patent is Micro-Tech, Nanjing, China. All other authors declare no conflict of interest. All authors declare that they conducted an independent research in the absence of any financial relationship with Micro-Tech, Nanjing, China. Ethics Approval Statement: This study was approved by the institutional review board, and written informed consent was obtained from all patients.