Endoscopy 2002; 34(5): 426-427
DOI: 10.1055/s-2002-25290
Letter to the Editor

© Georg Thieme Verlag Stuttgart · New York

Reply to Dr. Mosca

A.  Ferlitsch1
  • 1Department of Internal Medicine IV, Division of Gastroenterology and Hepatology, University of Vienna, Vienna, Austria
Further Information

Publication History

Publication Date:
22 April 2002 (online)

Dear Sir,

We are pleased by Dr. Mosca’s interest in our paper on a prospective multicenter evaluation of the Diamond stent for drainage of malignant biliary obstruction [1].

There was particular interest in the performance of the Diamond stent in patients with papillary and jejunal cancer: The subgroup of patients with ”other causes for biliary obstruction“ contained one case of papillary cancer, one jejunal cancer, one case of a pancreatic metastasis from a Merkel cell tumor, one pancreatic metastasis of a breast cancer, one metastasis of a leiomyosarcoma and one metastasis of an esophageal cancer. In this group all the implanted stents remained patent until the death of the patients; the median survival for this subgroup was 115 days. Patients with papillary, duodenal and metastatic cancer seem to benefit from metal stents also, but survival is shorter in this group.

Mosca notes that there were hilar stenoses in 12 % of the patients but 23 % of the inserted stents crossed the hilum, and enquires about the performance of these stents: Besides the 12 % of patients with hilar obstruction, in 14 patients the common bile duct stenosis was located so far proximally that the necessary overlap of the stenosis by the stent (2 cm) led to a bridging of the bifurcation. In addition there were three patients in whom two stents were implanted in parallel and coaxially (one to the right, one to the left side) crossing the bifurcation. The outcome in this subgroup did not differ significantly from the overall results.

Mosca enquires about the patients with stents ending above the papilla and about any difference in the patency of these stents: Some of the stents ended above the papilla simply because in some proximal stenoses even the longest stent did not reach the papilla; patency was not significantly different in this group.

Concerning the definition of successful drainage, the mean bilirubin value before procedure was 11.8 mg/dl, the mean value 5 days after the procedure was 5.2 mg/dl and it was 1.09 mg/dl after 3 months. Reviewing our data, we have to admit that our statement concerning a 50 % drop of bilirubin in 98 % of the patients 5 days after the procedure is misleading, since not every patient had elevated bilirubin levels and jaundice before implantation and not every patient with a previously placed plastic stent had stent occlusion. However, clinical improvement with reduction of jaundice or immediate drop of elevated bilirubin levels was seen in 98 % of our patients, but a drop below 50 % pre-procedure bilirubin level in this short period was seen only in 52 % after 5 days. We agree with Mosca that multifactorial parameters determine the bilirubin decrease and more than 5 days are usually needed to obtain a 50 % decrease in bilirubin, which therefore might be an inadequate marker for short-term drainage success.

Mosca notes that for one patient there was a 130-month period before Diamond stent insertion: This was a 85-year-old lady who was suffering from colorectal cancer with lymph node metastases diagnosed 130 months earlier. Before Diamond stent implantation this patient was treated with chemotherapeutic regimens; she died 28 days after stent insertion, due to cancer progression and cachexia.

There was specific interest concerning two patients who died from sepsis several days after stenting. Both patients died in other hospitals, and had the clinical diagnosis of septicemia. There were no statements from the pathologists concerning the stent function; however insufficient drainage as reason for early death after stent implantation due to sepsis cannot be ruled out.

The use of balloon dilation pre and post-implantation was challenged. In three patients balloon dilation was used to treat insufficient stent expansion; all these patients suffered from pancreatic head cancer, and special features of the tumor or the stenoses were not reported. In these patients there was no case of balloon dilation before stent implantation. Among the 11 patients, in whom balloon dilation was used prior to Diamond stent implantation, 10 were suffering from pancreatic head cancer and one had bile duct cancer, but the outcomes in these patients regarding stent patency and survival did not differ significantly from the overall results. Comparing the patients in whom lymph node metastases were the reason for bile duct obstruction with the remaining patients, no significantly different outcome was seen, as mentioned in our article.

Another point of interest is the frequency of duodenal stenoses: Duodenal stenoses were not registered systematically, although we agree that this is certainly an important point.

Mosca enquires about the eight long-term survivors, whose stents remained patent until day 477: When calculating the stent patency with the Kaplan-Meier method, the analysis takes into account that patients are lost due to death or unwillingness to participate, but do not reach the defined end point (stent occlusion). This is the reason why at day 477 (median stent patency) the patency analysis is based on just eight surviving patients. In this group stent occlusion occurred in four of the eight by the end of their follow-up in January 2000. Just one of these patients had distant metastasis; the other tested parameters of this subgroup are not significantly different.

Generally, we want to outline that the Diamond stent is not ideal, simply because there is no ideal stent, but we feel that this particular one is very useful and easy to handle in most clinical situations.

References

  • 1 Ferlitsch A, Oesterreicher C, Dumonceau J M. et al . Diamond stents for palliation of malignant bile duct obstruction: a prospective multicenter evaluation.  Endoscopy. 2001;  33 645-650

A. Ferlitsch, M.D.

Department of Internal Medicine IV · Divison of Gastroenterology and Hepatology ·University of Vienna

Waehringer Guertel 18 - 20 · 1090 Vienna · Austria

Fax: + 43-1-404004735 ·

Email: arnulf.ferlitsch@akh-wien.ac.at

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