K

K. Knyrim

Kliniken der Stadt Köln

Publishes on Gallbladder and Bile Duct Disorders, Colorectal Cancer Screening and Detection, Pediatric Hepatobiliary Diseases and Treatments. 37 papers and 2.2k citations.

37Publications
2.2kTotal Citations

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A Controlled Trial of an Expansile Metal Stent for Palliation of Esophageal Obstruction Due to Inoperable Cancer
K. Knyrim, Hans‐Joachim Wagner, N. Bethge et al.|New England Journal of Medicine|1993
Cited by 751Open Access

BACKGROUND: Esophageal obstruction due to cancer can produce debilitating dysphagia. Rapid palliation is usually possible with endoscopic placement of a plastic esophageal prosthesis, but this device has a high rate of complications. A new alternative is a metal-mesh stent that collapses to 3 mm in diameter at placement but can then expand up to 16 mm. METHODS: Patients with esophageal carcinoma (39 patients) or malignant extrinsic obstruction (3 patients) were randomly assigned to treatment with either a plastic prosthesis (16 mm in diameter) or an expansile metal-mesh stent. The patients were evaluated every six weeks until death. The degree of palliation was expressed as a dysphagia score and a Karnofsky performance score. RESULTS: Complications were significantly less frequent with the metal stents than with the plastic prostheses (no complications vs. nine; P < 0.001). The dysphagia and Karnofsky scores improved significantly and to a similar degree in both treatment groups. The most common causes of recurrent dysphagia were migration of the plastic prostheses (five patients) and ingrowth or overgrowth of the metal stents by tumor (five patients). The rates of reintervention were similar in both treatment groups, as were the 30-day mortality rates. The period of hospitalization after placement of a prosthesis was significantly longer in the group given plastic prostheses than in the group given metal stents (mean +/- SE, 12.5 +/- 2.1 vs. 5.4 +/- 1.0 days; P = 0.005). Despite their higher initial cost, the metal stents were cost effective because of the absence of fatal complications and the decrease in the hospital stay. CONCLUSIONS: Expansile metal stents are a safe and cost-effective alternative to conventional plastic endoprostheses in the treatment of esophageal obstruction due to inoperable cancer.

A Prospective, Randomized, Controlled Trial of Metal Stents for Malignant Obstruction of the Common Bile Duct
Cited by 498

Endoscopic insertion of biliary stents is the preferred method of palliation for inoperable malignant biliary obstruction; however, migration and clogging are frequent problems with conventional endoprostheses. We sought to determine if expandable metal stents offer improved palliation compared to conventional stents. Sixty-two patients with common bile duct lesions were randomized to receive polyethylene or metal stents. Stents were placed endoscopically or by the combined percutaneous-endoscopic route. Early results (< 1 month) were similar in both groups. Long-term follow-up (n = 28 polyethylene, median: 5 months; n = 27 metal, median: 5 months) showed a higher stent failure rate in the polyethylene (n = 12; 43%) compared to the metal group (n = 6; 22%). The incidence of cholangitis was significantly higher (p < 0.05) in the polyethylene (n = 10; 36%) compared to the metal group (n = 4; 15%). Life-table analysis showed a significantly reduced incidence of stent failure (p = 0.0035) in the metal stent compared to the polyethylene group. The total duration of hospital stay for treatment of stent related problems was significantly higher in the polyethylene (11.8 +/- 3 days) compared to the metal group (4 +/- 1.9 days; p = 0.02). The costs for retreatment because of stent failure were significantly higher in the plastic (DM 5900 +/- 1516) compared to the metal group (DM 2070 +/- 977). As a result, the overall costs (treatment of stent related complications & stents) were higher in the polyethylene group (DM 6000 +/- 1500).(ABSTRACT TRUNCATED AT 250 WORDS)

Plastic Endoprostheses versus Metal Stents in the Palliative Treatment of Malignant Hilar Biliary Obstruction. A Prospective and Randomized Trial
Cited by 335

This prospective and randomized trial sought to compare large-bore plastic endoprostheses (14 French) and self-expanding metal stents (24 French) in the palliative treatment of obstructive jaundice due to biliary hilar malignancies. Twenty patients with Type II-IV (Bismuth classification) hilar obstruction were randomized to treatment with either plastic or metal stents. Both treatment groups were well matched with regard to all assessed clinical criteria before stenting. Stent placement was uniformly successful in the metal group and in 88.9% of the plastic group. Early stent failure (< 30 days) occurred in two patients of the plastic stent group. Longterm (> 30 days), stent failure was observed in 50% of the plastic group and 18.2% of the metal stent group. All differences were not statistically significant. The number of re-interventions required to manage stent-related problems proved to be significantly higher in the plastic group (2.4 +/- 2.6) compared to the metal group (0.4 +/- 0.5). Hospitalization for treatment of stent complications was also significantly higher in the plastic treatment group. The costs calculated for stents and hospital stay for required re-interventions were therefore higher in the plastic stent group. In conclusion, metal stent insertion for palliation of hilar malignancies does not only offer higher success rates and higher patency rates compared to plastic stent insertion, but is also cost-effective since patients require fewer re-interventions.