Surgical Science, 2011, 2, 418-421
doi:10.4236/ss.2011.28091 Published Online October 2011 (http://www.SciRP.org/journal/ss)
Management of Recurrent Large Bowel Obstruction Due
to Stent Occlusion by ‘Stent-Over-Stent’:
A Case Report and Literature Review
Yi-Po Tsang, Hester Yui-Shan Cheung, Cliff Chi-Chiu Chung, Michael Ka-Wah Li
Department of Surgery, Pamela Youde Nethersole Eastern Hospital, Hong Kong SAR, China
Received May 8, 201 1; revised July 19, 2011; accepted September 9, 2011
Abstract
Endoscopic stenting for malignant large bowel obstruction is common nowadays. However, recurrent ob-
struction secondary to stent occlusion due to tumour ingrowth or overgrowth might occur. We reported a
case of a 70-year-old man with large bowel obstruction initially treated with colonic stenting. It was compli-
cated with recurrent intestinal obstruction, with colonoscopy showing stent blockage by tumour ingrowth
over distal part of the stent. Successful endoscopic implantation of additional colonic stent over the old stent
was achieved and intestinal obstruction was resolved afterwards.
Keywords: Colon, Intestinal Obstruction and Stenting
1. Introduction
Surgery was the only option in the past for malignant
large bowel obstruction (LBO), which usually presents
as sur gical e merge ncy. Ho wever, emergenc y surge ry per
se, and the associated stoma creation, carries high mor-
bidity and mortality [1-4]. On the other hand, endoscopic
placement of self-expandable metallic stent (SEMS) is
increasingly practised nowadays with lo w mortality rates
[1]. While clinical resolution of intestinal obstruction
usually happens within several days of successful place-
ment of SEMS, delayed stent occlusion due to tumour
ingrowth or overgrowth had been reported in literatures
[1], especially with the use of uncovered stents, leading
to recurrent obstruction. Herein we report a case of ma-
lignant LBO using covered stent, resulting in recurrent
intestinal obstruction due to ingrowth in the distal part,
which was successfully managed by endoscopic implan-
tation of additional colonic stent.
2. Case Report
A 70-year-old man who was lately diagnosed to have
inoperable lung cancer was admitted to the surgical ward
for intestinal obstr uction. Co mputed to mography sho wed
a tumour in descending colon with features of LBO; mul-
tiple liver metastases were present. In view of dissemi-
nated disease, SEMS was attempted as a palliative
measure to relieve the obstruction. Colonoscopy con-
firmed the presence of an obstructive growth in de-
scending colon, and a 10 cm ComVi enteral covered
colonic stent® (Taewoong Medical Co., Seoul, Korea)
was inserted under both endoscopic and fluoroscopic
guidance (Figure 1 and Figure 2). Following this the
intestinal obstruction resolved rapidly, with bowel open-
ing on the same day. The patient made an uneventful
recovery afterwards, and was discharged 3 days after
stent placement.
Figure 1. Endoscopic view of the obstructing tumour.

Y. -P. TSANG ET AL.419
Figure 2. Intestinal obstruction resolved after placement of
first colonic stent. Arrow points to the stent.
Figure 3. Recurrent intestinal obstruction resolved after
Two months later, the patient was readmitted with a
pi
. Discussion
urgery was the only option in the past for relieving ma-
EMS
ha
Colo-
ni
“stent-over-stent”—implantation of second colonic covered
stent (white arrow). Broken arrow indicates the original
stent.
cture of recurrent intestinal obstruction which failed to
resolve with conservative measure. Colonoscopy was
repeated for suspected stent blockage. On endoscopic
examination, tumour ingrowth was found over the distal
“uncovered” part of the stent, leading to recurrent ob-
struction; proxi mal to this the stent was other wise patent.
An additional 12 cm ComVi enteral covered colonic
stent® (Taewoong Medical Co., Seoul, Korea) was
placed over the distal part of the original stent. Bowel
opening resumed immediately after stent placement.
Subsequent abdominal x-rays showed r esolving i nt estinal
obstruction (Figure 3). The patient was discharged after
one week’s hospitalisation.
3
S
lignant LBO, which usually presents as surgical emer-
gency. However, emerge ncy surgery itself carries a hi gh
morbidity and mortality, and curative resection is feasi-
ble in only 30% of patients d ue to exte nsive tu mour [1,2 ].
In addition, emergency surgical procedures would often
end up in stoma creation, which again is associated with
high morbidity and mortality [3-4]. Moreover, stoma
creation was shown to have a high negative impact on
patients’ psychological well-being and quality of life
[5,6]. Around 40% - 60% of patients never have their
colostomies reversed in the rest of their lives [7,8].
Since first reported by Dohmoto in 1991 [9], S
s been e mplo yed a s a non- inva si ve mean s for reli eving
acute malignant LBO and a bridge to definitive elective
surgery in potentially resectable colorectal tumours
[10-12]. In palliative settings, SEMS also significantly
reduce the chance of stoma creation, length of hospital
stay, mortality rate, and medical complications compared
with palliative surgery [1,13-15]. Additionally, it allows
these patients to enjoy the full benefits of minimally in-
vasive surgery [16]. It is a safe procedure with low mor-
tality rates of approximately 1% [1,17]. Various reviews
have reported technical and clinical success rates of 75% -
100% and 84% - 100% respectively [1,10,18,19].
However, SEMS is not without complications.
c perforation, stent migration, stent occlusion, and
bleeding have been reported [1,10,17]. In particular, stent
occlusion is seen in around 10-16% of patients and oc-
curs more frequently in palliative settings [1,6,14,20]. It
is a common cause of delayed recurrent obstruction fol-
lowing apparently successful initial SEMS implantation,
especially with the use of uncovered stents [10,21]. Pro-
spective studies and systemic reviews showed that the
time for colonic reobstruction ranged from 48 hours to
480 days after stent placement [6,13,14,21]. This varia-
tion in stent pate ncy duration may be d ue to difference in
demographic factors, underlying malignancies, or types
of stents used [6,14].

Y. -P. TSANG ET AL. 420
stents are subject to tumour in-
gr
. Conclusions
conclusions, the present report serves as a reminder
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carried out to investigate the efficacy of this strategy.
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