Introduction
Superficial duodenal epithelial neoplasia (SDET) was previously considered a rare
disease [1]
[2]
[3]
[4]; estimated prevalence rates of 0.02 % to 0.5 % have been reported in autopsy series
[5]
[6]
[7]. However, the ability to detect SDET has been increasing with recent advances in
endoscopic technologies [8]. Due to the rarity of SDET, there are no established guidelines for treatment of
SDET except for ampullary tumors [9].
Endoscopic mucosal resection (EMR) is a simple procedure but sometimes fails in piecemeal
resection and is related to 20% to 30 % of local recurrence after piecemeal EMR [10]
[11]
[12]. Alternatively, ESD achieves secure en bloc resection even in larger lesions [13]
[14]
[15]
[16]
[17]. Recently we reported that ESD achieved more than 90 % of en bloc resection even
in lesions larger than 20 mm [17]. On the other hand, previous studies reported that duodenal ESD is associated with
more complications such as perforation and bleeding [17]
[18]
[19]
[20]
[21]
[22]
[23]
[24]
[25]. In particular, 13 % to 50 % incidence of perforation is reported in previous studies
[17]
[19]
[20]
[22]
[23]
[24]
[25]. Duodenal ESD is more effective as a secure local treatment but considered technically
challenging.
If we can predict technical difficulty of ESD, it would have clinical impact in that
we could better prepare according to technical difficulty for each patient. For example,
we could choose general anesthesia in the operating room for cases in which technical
difficulty is expected or conscious sedation in the endoscopy unit for cases anticipated
to be easier. In other organs, such as the stomach and colorectum, some clinical features
of the lesion such as location and size would predict technical difficulty [26]
[27]. However, to date, few studies have objectively analyzed predictors of technical
difficulty of duodenal ESD. Therefore, the aim of the current study was to elucidate
predictors of technical difficulty of duodenal ESD.
Patients and methods
Study design and patient eligibility
This was a retrospective observational study. From June 2010 to June 2017, a total
of 174 consecutive patients with SDET who underwent resection with ESD at our institute
were included. There was a case of intraoperative perforation requiring conversion
to surgery, and that case was excluded from data analysis. This study was performed
in accordance with the 2008 revision of the Helsinki Declaration. This is an accompanying
research study [17], and patient consent was obtained in the original research study. The study protocol
was approved by the institutional review board (20150221).
ESD procedure
In our institute, duodenal ESD is performed under either conscious sedation consisting
of benzodiazepine, pethidine, and dexmedetomidine or general anesthesia with intratracheal
intubation. The latter is applied for challenging cases (for example, lesions exceeding
40 mm or with poor scope maneuverability). ESD procedures were performed by six expert
endoscopists who had performed more than 1,000 ESD procedures and at least 200 in
each organ (esophagus, stomach, and colorectum) at the beginning of this study. ESD
procedures were performed principally using a therapeutic endoscope with a water jet
function (GIF- Q260 J, Olympus Medical Systems, Tokyo, Japan). This endoscope has
a 9.8-mm outer diameter, 3.2-mm working channel, and 210° upward angle.
A tapered tip hood was put on the tip of the endoscope to facilitate to enter narrow
submucosal space (ST Hood Fujifilm Corp, Tokyo, Japan). Generally, a submucosal injection
of 10 % glycerine solution (Glyceol Chugai Pharmaceutical Co., Ltd, Tokyo, Japan)
with epinephrine (dilution 1:400,000) was administered. In difficult cases, 0.4 %
sodium hyaluronate (Mucoup, Boston Scientific Japan, Tokyo, Japan) was used as needed.
A mucosal incision was made or submucosal dissection was performed using a DualKnife
or a DualKnife J with a length of 1.5 mm (Olympus Medical Systems, Tokyo, Japan).
A HooKknife (Olympus Medical Systems, Tokyo, Japan) was used in difficult cases, such
as in cases with poor scope maneuverability. Minor bleeding was treated with these
devices by placing the tip of the device into the outer sheath; however, in cases
of spurting bleeding, hemostatic forceps (Coagrasper, Olympus Medical Systems, Tokyo,
Japan) were used. These energy devices were powered by a high-frequency electrosurgical
unit (VIO 300 D, ERBE Elektromedizin, Tübingen, Germany) with dry cut (effect 3 – 30 W)
for mucosal incision, swift coagulation (effect 4 – 30W) for submucosal dissection,
and soft coagulation (effect 5 – 50 W) for hemostasis.
Post-ESD management
Patients were fasted for 2 days, including the day of the ESD procedure, and received
intravenous hydration. After evaluating results of blood examinations and abdominal
X-rays, the patients were allowed to drink on postoperative Day (POD) 2. The patients
were allowed to begin a liquid diet on POD 3 and were generally discharged on POD
5. The timing of permitting patients to drink and eat did not differ even in cases
of perforation unless there were no symptoms. We did not use prophylactic antibiotics
routinely. Patients took proton pump inhibitors (rabeprazole 20 mg/day, lansoprazole
30 mg/day, or esomeprazole 20 mg/day) for 3 weeks after ESD.
Measured outcomes
We collected information on procedure time and intraprocedural perforation rate as
data associated with the technical difficulty of duodenal ESD. In this study, we defined
patients with technical difficulty as patients with either a prolonged procedure time
or intraprocedural perforation. We defined prolonged procedure time as procedure time
exceeding the procedure time of the first quartile.
Statistical analysis
In this study, we performed logistic regression analysis to identify risk factors
for technical difficulty, intraprocedural perforation, and prolonged procedure time.
Longitudinal lesion location (duodenal flexure including the supraduodenal angle (SDA)
or inferior duodenal angle [IDA] vs. other locations), site (posterior wall vs. others),
lesion size (–39 mm vs. ≥ 40 mm), and occupied circumference (less than half vs. more
than half the duodenum) were selected as influencing factors. Statistical analysis
was performed using JMP software (ver. 13.0.0, SAS Institute, Inc., Cary, North Carolina,
United States), and a P < 0.05 was considered statistically significant.
Results
Patient characteristics
Characteristics of patients included in the study are described in [Table 1]. Approximately 20 % of lesions were located in the duodenal flexure. Mean lesion
size was 27.4 ± 0.96 mm. More than 90 % of lesions occupied a circumference of less
than one-half the duodenum. There were three cases of local residual recurrence after
previous treatment.
Table 1
Clinical characteristics of the analyzed cases.
Age
|
Mean ± SEM
|
62.8 ± 0.91
|
Sex
|
Female
|
67 %
|
Location
|
Bulbs
|
14 %
|
Superior duodenal angle
|
9 %
|
Descending part
|
66 %
|
Inferior duodenal angle
|
8 %
|
Transverse part
|
3 %
|
Site
|
Anterior wall
|
15 %
|
Lateral wall
|
20 %
|
Posterior wall
|
33 %
|
Medial wall
|
32 %
|
Lesion size
|
Mean ± SEM, mm
|
27.4 ± 0.96
|
Occupied circumference
|
> 1/2
|
92 %
|
< 1/2
|
8 %
|
Macroscopic type
|
0-I
|
7 %
|
0-IIa
|
77 %
|
0-IIc
|
16 %
|
Clinical outcomes of duodenal ESD
Clinical outcomes of duodenal ESD are shown in [Table 2]. Resection in a single piece and R0 resection rate were performed in 97.7 % and
84.4 % of cases, respectively. In one case, conversion to laparoscopic partial duodenectomy
was required due to massive bleeding and perforation caused by poor maneuverability
of endoscope. Median procedure time was 50 minutes and 26.6 % of patients had a procedure
time longer than 100 minutes, which was the first quartile of the procedure time.
Intraprocedural perforation occurred in 12.7 % of the included patients. Thus, 34.5 %
of patients had technical difficulties during duodenal ESD.
Table 2
Clinical outcomes of duodenal ESD.
Procedure time
|
Median [range], min
|
50 [10 – 360]
|
> 100 min, n (%)
|
46 (26.6 %)
|
Resection in a single piece
|
Possible, n (%)
|
170 (97.7 %)
|
R0 resection
|
Possible, n (%)
|
147 (84.4 %)
|
Perforation
|
Present, n (%)
|
22 (12.7 %)
|
Bleeding
|
Present, n (%)
|
164 (5.2 %)
|
Cases with technical difficulty
|
Present, n (%)
|
60 (34.5 %)
|
Predictors for difficult ESD, intraprocedural perforation, and prolonged procedure
time
We performed logistic regression analysis to determine predictors for difficult ESD,
intraprocedural perforation, and prolonged procedure time. In univariate analysis,
lesion location in the duodenal flexure, larger lesion size, and an occupied circumference
of more than half the duodenum were associated with a significant increase in technical
difficulty of duodenal ESD, while lesion location in the posterior wall was associated
with significant decrease in technical difficulty of ESD. In multivariate analysis,
lesion location in the duodenal flexure (OR, 2.61; 95 % confidence interval [CI],
1.02 – 6.68), larger lesion size (OR, 5.26; 95 % CI, 2.15 – 12.9), and an occupied
circumference of more than half the duodenum (OR, 5.80; 95 % CI, 1.83 – 18.4) were
associated with a significant increase in technical difficulty ([Table 3]).
Table 3
Predictors of technical difficulty.
Variable
|
Univariate
|
Multivariate
|
Odds ratio
|
95 % CI
|
P value
|
Odds ratio
|
95 % CI
|
P value
|
Location
|
Duodenal flexure (SDA/IDA)
|
2.83
|
1.25 – 6.37
|
0.012[1]
|
2.61
|
1.02 – 6.68
|
0.047[1]
|
Others
|
1
|
|
|
1
|
|
|
Site
|
Posterior wall
|
1.49
|
0.75 – 2.96
|
0.26
|
0.94
|
0.42 – 2.11
|
0.89
|
Others
|
1
|
|
|
1
|
|
|
Lesion size
|
> 40 mm
|
1.08
|
0.86 – 1.53
|
< 0.01[1]
|
5.26
|
2.15 – 12.9
|
< 0.01[1]
|
≤ 39 mm
|
1
|
|
|
1
|
|
|
Occupied
|
More than 1/2
|
12.6
|
4.47 – 35.7
|
< 0.01[1]
|
5.80
|
1.83 – 18.4
|
< 0.01[1]
|
circumference
|
Less than 1/2
|
1
|
|
|
1
|
|
|
SDA, supraduodenal angle; IDA, inferior duodenal angle.
1 Statistically significant
Larger lesion size and an occupied circumference of more than half the duodenum were
significantly associated with intraprocedural perforation in univariate analysis,
while only larger lesion size was significantly associated with intraprocedural perforation
(OR, 3.84; 95 % CI, 1.22 – 12.1) in multivariate analysis ([Table 4]).
Table 4
Predictors of intraprocedural perforation.
Variable
|
Univariate
|
Multivariate
|
Odds ratio
|
95 % CI
|
P value
|
Odds ratio
|
95 % CI
|
P value
|
Location
|
Duodenal flexure (SDA/IDA)
|
1.56
|
0.52 – 4.62
|
0.44
|
1.06
|
0.31 – 3.59
|
0.93
|
Others
|
1
|
1
|
Site
|
Posterior wall
|
1.58
|
0.63 – 3.96
|
0.33
|
2.38
|
0.85 – 6.66
|
0.10
|
Others
|
1
|
1
|
Size of lesion
|
> 40 mm
|
5.04
|
1.99 – 12.8
|
< 0.01[1]
|
3.84
|
1.22 – 12.1
|
0.022[1]
|
≤ 39 mm
|
1
|
1
|
Occupied circumference
|
More than 1/2
|
5.12
|
1.92 – 13.7
|
< 0.01[1]
|
2.70
|
0.81 – 8.95
|
0.10
|
Less than 1/2
|
1
|
1
|
SDA, supraduodenal angle; IDA, duodenal angle.
1 Statistically significant
Lesion location in the duodenal flexure, larger lesion size, and occupied circumference
of more than half the duodenum were associated with a significant increase in technical
difficulty of ESD in terms of prolonged procedure time, while lesion location in the
posterior wall was associated with a significant decrease in technical difficulty
of ESD in univariate analysis. In multivariate analysis, lesion location in the duodenal
flexural (OR, 3.31; 95 % CI, 1.21 – 9.07), larger lesion size (OR, 5.59; 95% CI, 2.20 – 14.2),
and an occupied circumference of more than half the duodenum (OR, 7.83; 95 % CI, 2.52 – 24.3)
were associated with a significant increase in technical difficulty ([Table 5]).
Table 5
Predictors of prolonged procedure time.
Variable
|
Univariate
|
Multivariate
|
Odds ratio
|
95 % CI
|
P value
|
Odds ratio
|
95 % CI
|
P value
|
Location
|
Flexural part (SDA/IDA)
|
3.27
|
1.43 – 7.47
|
< 0.01[1]
|
3.31
|
1.21 – 9.07
|
0.020[1]
|
Others
|
1
|
1
|
Site
|
Posterior wall
|
0.43
|
0.19 – 0.97
|
0.032[1]
|
2.00
|
0.72 – 5.52
|
0.18
|
Others
|
1
|
1
|
Lesion size
|
> 40 mm
|
11.5
|
5.11 – 25.7
|
< 0.01[1]
|
5.59
|
2.20 – 14.2
|
< 0.01[1]
|
≥ 39 mm
|
1
|
1
|
Occupied circumference
|
More than 1/2
|
16.9
|
6.20 – 46.2
|
< 0.01[1]
|
7.83
|
2.52 – 24.3
|
< 0.01[1]
|
Less than 1/2
|
1
|
1
|
SDA, supraduodenal angle; IDA, inferior duodenal angle.
1 Statistically significant
Discussion
In this retrospective study, we tried to find predictors of technical difficulty of
duodenal ESD through analysis of outcomes of duodenal ESD in 174 consecutive patients.
Longitudinal lesion location in the duodenal flexure, lesion size larger than 40 mm,
and an occupied circumference of more than half the duodenum were significantly associated
with technical difficulty. In terms of intraprocedural perforation, larger lesion
size was the only predictor, and for prolonged procedure time, longitudinal lesion
location in the duodenal flexure, lesion size larger than 40 mm, and an occupied circumference
of more than half the duodenum were independent predictors.
Advances in endoscopic devices and accumulation of knowledge of management of complications
and technical tips for ESD have contributed to widespread of ESD especially in Japan.
Many studies have revealed favorable outcomes of ESD with low morbidity rates, favorable
R0 resection rates, and high organ preservation rates for lesions in the esophagus,
stomach, and colorectum [14]
[15]
[28]. Thus, ESD for superficial esophageal, gastric, or colorectal epithelial lesions
is a standard treatment in Japan. Indeed, more than 50 % of early gastric cancers
are treated by ESD, and esophageal, gastric, and colorectal ESD have been approved
by healthcare insurance.
On the other hand, duodenal ESD has been considered to be very high risk, with a 13 %
to 50 % incidence of perforation in previous studies [19]
[20]
[22]
[23]
[24]
[25]. This high complication rate reflects the technical difficulty of duodenal ESD.
In fact, the duodenum, especially the distal part, is very far from the mouth so that
the maneuverability of the endoscope is often limited, and sometimes it is quite difficult
to even approach the lesion. Due to the narrow space of the submucosal layer, it is
difficult to go beneath the lesion. Burner’s glands and vessels are rich in the submucosal
layer; therefore, visualization tends to be poor while dissecting this layer. Most
importantly, the wall of the duodenum is extremely thin; therefore, perforation occurs
easily [29].
As mentioned above, duodenal ESD is technically difficult; however, recent advances
in devices and endoscopic techniques have contributed to improvement in outcomes.
Recently, we reported a novel ESD technique, the “water pressure method,” which utilizes
a pressure jet of water through a transparent hood with a small-caliber tip to open
a narrow space in the submucosa after initial mucosal incision and submucosal dissection
[30]. The pocket creation method (PCM) is also a novel endoscopic technique proposed
by Miura and Yamamoto. In this method, a submucosal pocket is created at the beginning
without extending the mucosal incision; as a result, stable conditions and good submucosal
visualization can be obtained [31]. And a traction-assisted ESD technique has been reported [32]
[33]. Using these modified endoscopic treatments, outcomes of duodenal ESD have improved.
In fact, in the latest report about short-term outcomes of duodenal ESD [17], the perforation rate was 15.5 %, and this is one of the lowest incidences despite
the large sample size of the study.
With improvement in outcomes, duodenal ESD is expected to become used more widely;
therefore, it is important to identify features of difficult lesions. Here, we found
that longitudinal lesion location in the duodenal flexure, lesion size larger than
40 mm, and occupied circumference of more than half the duodenum were predictors of
technical difficulty. It is reasonable that the proportion of difficult ESD procedures
increased with increasing lesion size. In addition, our results suggest that there
are two possible reasons for technical difficulty. In lesions located in the duodenal
flexure, maneuverability of the endoscope tends to be poor. Furthermore, it is difficult
to adjust device direction in situations in which lesions occupy a large circumference
within the duodenum because the working channel of the endoscope is commonly located
at the 6- to 7-o’clock position, making it difficult to almost impossible to access
the lesion when the lesion is located in the opposite direction.
Our study has several limitations, mainly due to its single-centered retrospective
study design. First, all procedures were performed by expert endoscopists at a high-volume
center, and the results are difficult to generalize. Second, we could not eliminate
a certain degree of selection bias, although we only included consecutive patients.
Third, we could not analyze subjective factors associated with technical difficulty,
such as the psychological stress of the operator. Due to these limitations, the results
of our study should be interpreted carefully.
Conclusion
In conclusion, the current study revealed that longitudinal lesion location in the
duodenal flexure, lesion size larger than 40 mm, and occupied circumference of more
than half the duodenum were significantly associated with technical difficulty of
duodenal ESD. These findings would be helpful for risk stratification and management
of patients undergoing duodenal ESD.