[Metal endoprostheses for endoscopic therapy in malignant bronchial tumors]

Treatment of inoperable tracheobronchial obstructive lesions with the Palmaz stent

PURPOSE

The treatment of inoperable tracheobronchial stenoses with Palmaz stents is analyzed in terms of the clinical effect, typical complications, and long-term follow-up.

METHODS

Twenty-seven Palmaz stents were placed in 22 patients with the help of a rigid bronchoscope.

RESULTS

Stents were implanted in the distal trachea, the main bronchi, and the lower lobe bronchi. Twenty-one of 22 patients reported an immediate subjective improvement in their respiratory situation. The mean survival time was 12 months; in two patients the stents were well tolerated for up to 40 months. A redilation of three stents was successful up to 33 months. In three cases a dislocation of the stent was observed; after bronchoscopic retraction a new stent was successfully implanted in each case. CONCLUSIONoff Treatment of inoperable tracheobronchial stenoses with the Palmaz stent is a safe procedure that provides an immediate improvement of the patient's pulmonary situation. The Palmaz stent shows a minimal complication rate in the long-term follow-up.

Implantation of Accuflex and Strecker stents in malignant bronchial stenoses by flexible bronchoscopy

Silicone and metal stents are available for the treatment of malignant bronchial stenoses. This project sought to compare the self-expanding nitinol Accuflex stent (Boston Scientific Corp; Watertown, Mass) with the passively expandable tantalum Strecker stent (Boston Scientific Corp; Watertown, Mass), both implanted by flexible bronchoscopy under local anesthesia and sedation. In 51 patients with malignant bronchial stenosis, 14 nitinol and 51 tantalum stents were used and stenoses of 75 to 100% were treated. The intervention was successful in all but one patient; a mean patency of 93% was achieved. In the follow-up period, the probability of survival was significantly lower in patients with total bronchus occlusion than in patients with stenotic alterations (44 vs 109 days; p<0.05). In 10 patients, lung function analysis after stent implantation revealed a significant increase in PaO2 (65 vs 71 mm Hg; p<0.01), inspiratory vital capacity (2.5 vs 2.7 L; p<0.05), and FEV1 (1.8 vs 2.0 L; p<0.05). Mucus retention was the main (39%) adverse factor in the early phase after stent implantation, whereas tumor penetration became the most frequent problem (67%) in the later phase. Recanalizing interventions were necessary in 18% of the cases in which tumor penetration occurred. Stent distortion occurred in 12 patients with Strecker and in none with Accuflex stents. In comparison to the Strecker stent, the self-expanding Accuflex stent is preferable owing to its excellent flexibility and faster delivery system. Both types of stents could be sufficiently deployed within the lesion and allowed for highly precise positioning. Furthermore, no general anesthesia was required. The fiberbronchoscopic mode of implantation under sedation is very efficient even for tumor patients with severe impairment of their physical and respiratory condition.

The use of the covered Wallstent for the palliative treatment of inoperable tracheobronchial cancers. A prospective, multicenter study

STUDY OBJECTIVE

To investigate the safety, efficacy, and tolerance of the covered Wallstent for the palliative treatment of inoperable tracheobronchial cancer.

DESIGN

An 8-month prospective study employing either a rigid bronchoscope or a flexible delivery system for prosthesis insertion.

SETTING

Multicentric setting involving four teaching hospitals in Switzerland and Germany.

PATIENTS

Forty patients (29 men, 11 women), average age of 62 years, presenting with an inoperable tracheobronchial cancer.

INTERVENTIONS

After partial airway recanalization with an Nd-YAG laser, the covered Wallstent was inserted 23 times using a rigid bronchoscope (Rigidstep device), and 27 times using a flexible delivery system (Telestep device) under fluoroscopic and endoscopic visualization.

RESULTS

Clinical and endoscopic examination at 1, 30, and 90 days showed improvement in the bronchial lumen and in the dyspnea index. No serious complication (death, perforation, hemorrhage, inability to remove an improperly placed prosthesis) was observed during surgery. Late complications included migration (12%), inflammatory granulations or tumor regrowth at the tip of the prosthesis (36%), and symptomatic retention of secretion (38%).

CONCLUSIONS

Compared with other tracheobronchial prostheses, notably the Dumon stent, the covered Wallstent presents the following advantages: insertion with visual guidance, treatment of extrinsic compressions and esophagobronchial fistulas, and little chance of migration when the prosthesis diameter is chosen correctly. The following disadvantages can be noted: high price; both repositioning and extraction of the released stent are more difficult, though certainly possible; and risk of granulations at the tips of the prosthesis and retention of secretions. Suggestions are made for potential improvements to the stent and insertion system that may result in a significant decrease in early and late complications.