Introduction
The incidental finding of gastric polyps occurs in about 1.2 % – 8.0 % of patients
undergoing upper gastrointestinal endoscopy [1]
[2]
[3]
[4]. The exact prevalence of gastric hyperplastic polyps (GHPs) is unknown, being reported
in 7 % – 88 % of lesions resected in the stomach [4]
[5]
[6]. Several risk factors for GHPs have been identified, such as chronic Helicobacter pylori infection, chronic atrophic gastritis [7], liver cirrhosis and portal hypertension [8], autoimmune gastritis [9], partial gastric surgery [10], and Ménétrier’s disease [11].
Although mostly asymptomatic, GHPs can present as anemia due to occult bleeding or,
in rare cases, as severe gastrointestinal bleeding. Their potential for neoplastic
transformation has been demonstrated, with a prevalence of dysplasia (low and high
grade) ranging from 1.5 % to 4.4 %, and a prevalence of adenocarcinoma of between
1.1 % and 2.1 % [12]
[13]
[14]. A GHP size > 10 mm has been identified as a risk factor for neoplastic transformation
[12]. Current French guidelines recommend the resection of gastric polyps when symptomatic
or when their size is > 10 mm [15]. For the latter, the goal of endoscopic resection is to diagnose and treat the GHP
with neoplastic transformation. However, many cases of local recurrence are reported
in the literature, sometimes with severe profuse gastric spreading, even following
R0 resection with free lateral and deep margins [16]. Thus, the benefit – risk balance of the resection remains unclear.
The present study aimed to evaluate the risk of GHP recurrence after endoscopic resection
of large GHPs (≥ 10 mm), and to identify risk factors for recurrence and neoplastic
transformation.
Methods
Study design
This work was a retrospective European multicenter study focusing on GHPs, and included
patients from seven academic and three nonacademic hospitals in France, Spain, and
Croatia, between June 2007 and August 2018. All participating operators had extensive
experience in endoscopic mucosal resection (EMR) and endoscopic submucosal dissection
(ESD).
Inclusion and exclusion criteria
Patients were included if they fulfilled the following criteria: age ≥ 18 years, endoscopic
resection of at least one GHP with a size ≥ 10 mm, and an endoscopic follow-up at
least 3 months after resection. Patients were excluded if the GHP was already a recurrence
at the time of the first endoscopy, or if they underwent surgical resection of GHPs
or had hereditary gastric polyposis (familial adenomatous polyposis or hamartomatous
polyposis).
Definitions
The histological diagnosis of GHP was made using the following criteria: the presence
of foveolar hyperplasia, with long, deep, and hypersecreting crypts, an inflammatory
and abundant chorion, and sometimes an ascension of smooth muscle cells. A large GHP
was defined as a size ≥ 10 mm. A GHP was considered recurrent if it had grown at the
site of the previous resection, on the scar when visible. En bloc resection was defined
as a complete resection without fragmentation during removal of the piece. R0 resections
were defined histologically by free lateral and deep margins. Neoplastic transformations
were defined histologically by the presence of dysplasia or adenocarcinoma within
GHPs.
Patients and data collection
All patients were retrospectively included using either the disease coding software
or the prospectively collected databases of each center. All data were retrieved from
the endoscopy, pathology, and hospitalization reports, collected anonymously, and
collated in an Excel spreadsheet (Excel; Microsoft, Redmond, Washington, USA).
Objectives
The primary end point was the proportion of recurrence, defined by the presence of
a histologically confirmed GHP at the site of a previous complete endoscopic resection
at least 3 months after the initial complete resection.
Secondary end points were: risk factors for recurrence of GHPs, proportion and risk
factors for neoplastic transformation in GHPs, proportion of en bloc and R0 resections
according to the technique used (EMR, ESD, hybrid), and safety of the procedure (within
the first month) including perforations (complete or partial, i. e. with target sign)
and bleedings.
Statistical analyses
Quantitative variables were described by the mean and standard deviation (SD), the
range, or the median and interquartile range (IQR); qualitative variables were described
by the frequency and percentage of each modality (excluding missing data from percentages).
The effect of factors on the risk of recurrence or neoplastic transformation was quantified
using odds ratios (ORs) with their 95 % confidence intervals (CIs). Comparison between
groups was performed by Student’s t, chi-squared or Kruskall – Wallis tests. Univariate analyses were performed using
mixed logistic regressions (multiple polyp by patient). Multivariate analysis was
then performed by including all factors with P values < 0.2 in univariate analyses, followed by backward selection. The survival
without recurrence curve was produced by the Kaplan – Meier method. A P value < 0.05 was considered significant. Analyses were performed using R software
version 3.4.4 (R Foundation for Statistical Computing, Vienna, Austria. https://cran.r-project.org/mirrors.html). Statistical analyses were performed on all available data.
Ethical considerations
The study was conducted according to the Declaration of Helsinki and received approval
from the ethics committee of the Hospices Civils de Lyon (28 August 2018).
Results
Patient and lesion characteristics
From June 2007 to August 2018, 145 GHPs of ≥ 10 mm were included in the study. Macroscopic
aspects of GHPs are presented in [Fig. 1]. Endoscopic resection of GHPs was performed in 108 patients (mean age 65.9 years
[SD 11.9]; 56.1 % male (n = 60). The mean number of GHPs was 1.34 per patient (range
1 – 6). A single polyp was recorded in 79.6 % of patients, two polyps in 13.0 % of
patients, and three or more polyps in 7.4 % of patients.
Fig. 1 Endoscopic pictures of different cases of gastric hyperplastic polyps. a Large reddish hyperplastic polyp of the fundus on white light imaging. b Hyperplastic polyp of the antrum on narrow band imaging, with large regular mucosal
pattern. c Flat hyperplastic polyp of the corpus, with reddish aspect. d Irregular mucosal pattern of large hyperplastic polyp without dysplasia on narrow
band imaging.
Of the 108 patients, 17.8 % had cirrhotic and 13.6 % had a noncirrhotic chronic liver
disease. A history or ongoing infection with H. pylori was detected in 14.7 % of patients. Histological findings showed gastritis in 77.5 %
of patients, intestinal metaplasia in 30.2 %, and gastric atrophy in 28.1 % of patients.
Finally, 45.4 % of patients had a clinical manifestation of their GHPs. Of these,
80.0 % had anemia, 11.4 % had upper gastrointestinal bleeding, and 8.6 % had an isolated
iron deficiency. Other nonspecific upper gastrointestinal symptoms were reported,
such as epigastric pain and gastroesophageal reflux disease.
The median size of GHPs was 15.0 mm (IQR 10.0 – 25.3) and 66.2 % of were located in
the antrum (including the angulus). ESD was used in 17.9 % of GHP resections, EMR
in 77.2 %, and a hybrid technique in 4.8 %. R0 resection was achieved in 108 resections
(75.5 %) ([Table 1]). The median time to the first endoscopic follow-up was 8.8 months (IQR 3.7 – 16.6).
The number of endoscopic follow-ups following the first resection ranged from 1 (57.2 %
of GHP resections) to 5 (2.0 % of GHP resections).
Table 1
Baseline characteristics of patients and risks factors of recurrence in univariate
analysis.
|
Characteristic
|
Total numbers[1]
|
Recurrence[2]
|
Univariate analysis
|
|
Patients n = 108
|
GHPs n = 145
|
No n = 71
|
Yes n = 74
|
OR (95 %CI)
|
P
|
|
Age
|
65.9 (11.9)
|
65.6 (11.2)
|
66.7 (12.3)
|
64.5 (10.2)
|
|
0.24
|
|
mean (SD), years
|
|
|
43 (39.8)
|
63 (43.4)
|
24 (38.1)
|
39 (61.9)
|
|
|
|
|
65 (60.2)
|
82 (56.6)
|
47 (57.3)
|
35 (42.7)
|
0.34 (0.12 – 0.96)
|
0.03
|
|
Sex, n (%)
|
|
|
60 (56.1)
|
88 (61.1)
|
37 (42.0)
|
51 (58.0)
|
2.48 (0.91 – 6.73)
|
0.06
|
|
|
47 (43.9)
|
56 (38.9)
|
34 (60.7)
|
22 (39.3)
|
|
|
|
|
1
|
1
|
0
|
1
|
|
|
|
Cirrhosis, n (%)
|
|
|
19 (17.8)
|
29 (20.1)
|
6 (20.7)
|
23 (79.3)
|
6.57 (1.74 – 24.84)
|
0.002
|
|
|
88 (82.2)
|
115 (79.9)
|
65 (56.5)
|
50 (43.5)
|
|
|
|
|
1
|
1
|
0
|
1
|
|
|
|
H. pylori infection, n (%)
|
|
|
15 (14.7)
|
19 (13.7)
|
9 (47.4)
|
10 (52.6)
|
1.22 (0.30 – 4.91)
|
0.78
|
|
|
87 (85.3)
|
120 (86.3)
|
58 (48.3)
|
62 (51.7)
|
|
|
|
|
6
|
6
|
4
|
2
|
|
|
|
Gastritis, n (%)
|
|
|
79 (77.5)
|
106 (76.3)
|
50 (47.2)
|
56 (52.8)
|
2.20 (0.62 – 7.80)
|
0.20
|
|
|
23 (22.5)
|
33 (23.7)
|
19 (57.6)
|
14 (42.4)
|
|
|
|
|
6
|
6
|
2
|
4
|
|
|
|
Gastric intestinal metaplasia, n (%)
|
|
|
29 (30.2)
|
41 (30.8)
|
18 (43.9)
|
23 (56.1)
|
1.83 (0.58 – 5.76)
|
0.30
|
|
|
67 (69.8)
|
92 (69.2)
|
50 (54.3)
|
42 (45.7)
|
|
|
|
|
12
|
12
|
3
|
9
|
|
|
|
Gastric atrophy, n (%)
|
|
|
27 (28.1)
|
33 (24.8)
|
20 (60.6)
|
13 (39.4)
|
0.61 (0.60 – 0.62)
|
0.41
|
|
|
69 (71.9)
|
100 (75.2)
|
48 (48.0)
|
52 (52.0)
|
|
|
|
|
12
|
12
|
3
|
9
|
|
|
|
PPI intake, n (%)
|
|
|
66 (62.3)
|
97 (67.8)
|
44 (45.4)
|
53 (54.6)
|
1.87 (0.68 – 5.20)
|
0.22
|
|
|
40 (37.7)
|
46 (32.2)
|
27 (58.7)
|
19 (41.3)
|
|
|
|
|
2
|
2
|
0
|
2
|
|
|
|
NSAID or aspirin intake, n (%)
|
|
|
22 (22.4)
|
31 (23.0)
|
10 (32.3)
|
21 (67.7)
|
3.04 (0.89 – 10.33)
|
0.07
|
|
|
76 (77.6)
|
104 (77.0)
|
58 (55.8)
|
46 (44.2)
|
|
|
|
|
10
|
10
|
3
|
7
|
|
|
|
History of gastric surgery, n (%)
|
|
|
6 (6.1)
|
8 (5.8)
|
5 (62.5)
|
3 (37.5)
|
0.61 (0.08 – 4.87)
|
0.64
|
|
|
94 (95.9)
|
129 (94.2)
|
64 (49.6)
|
65 (50.4)
|
|
|
|
|
10
|
8
|
2
|
6
|
|
|
|
GHP size
|
|
|
|
|
15.0 (12.0 – 25.0)
|
20.0 (10.0 – 29.0)
|
|
|
|
|
|
108 (75.0)
|
54 (50.0)
|
54 (50.0)
|
|
|
|
|
|
36 (25.0)
|
17 (47.2)
|
19 (52.8)
|
1.42 (0.50 – 4.04)
|
0.51
|
|
|
|
1
|
0
|
1
|
|
|
|
Location, n (%)
|
|
|
|
96 (66.2)
|
39 (40.6)
|
57 (59.4)
|
|
|
|
|
|
49 (33.8)
|
32 (65.3)
|
17 (34.7)
|
0.35 (0.14 – 0.87)
|
0.02
|
|
Neoplastic transformation at the resection time, n (%)
|
|
|
|
15 (10.4)
|
8 (53.3)
|
7 (46.7)
|
1.06 (0.25 – 4.59)
|
0.94
|
|
|
|
129 (89.6)
|
63 (48.8)
|
66 (51.2)
|
|
|
|
|
|
1
|
0
|
1
|
|
|
|
En bloc resection, n (%)
|
|
|
|
124 (86.7)
|
62 (50.0)
|
62 (50.0)
|
0.71 (0.19 – 2.68)
|
0.61
|
|
|
|
19 (13.3)
|
9 (47.4)
|
10 (52.6)
|
|
|
|
|
|
2
|
0
|
2
|
|
|
|
R0 resection, n (%)
|
|
|
|
108 (75.5)
|
55 (50.9)
|
53 (49.1)
|
0.91 (0.31 – 2.67)
|
0.86
|
|
|
|
35 (24.5)
|
16 (45.7)
|
19 (54.3)
|
|
|
|
|
|
2
|
0
|
2
|
|
|
|
Endoscopic resection procedure, n (%)
|
|
|
|
112 (77.2)
|
52 (46.4)
|
60 (53.6)
|
|
|
|
|
|
26 (17.9)
|
14 (53.8)
|
12 (46.2)
|
0.87 (0.27 – 2.78)
|
0.61
|
|
|
|
7 (4.8)
|
5 (71.4)
|
2 (28.6)
|
0.34 (0.04 – 3.06)
|
|
GHP, gastric hyperplastic polyp; OR, odds ratio; CI, confidence interval; SD, standard
deviation; PPI, proton-pump inhibitor; NSAID, nonsteroidal anti-inflammatory drug;
IQR, interquartile range; EMR, endoscopic mucosal resection; ESD, endoscopic submucosal
dissection.
1 Missing data not included in percentage calculations.
2 Percentages calculated as proportion of GHPs for the respective characteristics.
Primary objective
After initial resection, 74 recurrent GHPs (51.0 %, 95 %CI 42.6 – 59.4) were identified
in 55 patients ([Table 1]). At 48 months, survival without recurrence was estimated at 22.2 % (95 %CI 13.8 – 35.7).
The median survival without recurrence was 20.0 months (95 %CI 15.8 – 31.9) ([Fig. 2]).
Fig. 2 Survival without recurrence. solid line, survival curve; dashed lines, 95 % confidence
interval.
Risk factors for GHP recurrence
Univariate analysis found that patients aged ≤ 65 years, or with cirrhosis, or GHPs
located in the antrum had a higher risk of recurrence. Among patients with cirrhosis,
79.3 % of resected GHPs recurred vs. 43.5 % in the noncirrhotic population. Following
a resection of antral GHP, the recurrence proportion was 59.4 % vs. 34.7 % for corpus
GHPs ([Table 1]).
Multivariate analysis followed by backward selection found that, although antral location
tended to be a risk factor (P = 0.08), only cirrhosis remained significant for GHP recurrence after endoscopic
resection (adjusted OR 4.82, 95 %CI 1.33 – 17.46; P = 0.02) ([Table 2]).
Table 2
Risk factors for recurrence in multivariate analysis after backward selection.
|
OR (95 %CI)
|
P
|
|
Cirrhosis (yes)
|
4.82 (1.33 – 17.46)
|
0.02
|
|
Location (corpus vs. antrum-angulus)
|
0.44 (0.17 – 1.10)
|
0.08
|
OR, odds ratio; CI, confidence interval.
Patients with cirrhosis
In patients with cirrhosis, the proportion of males was higher (78.9 %) than in the
noncirrhotic population (51.1 %), but the proportions of en bloc and R0 resections
were similar in both populations (85.8 % and 77.0 % vs. 89.7 % and 69.0 %, respectively).
Neoplastic transformation was found in 6.9 % of GHPs in patients with cirrhosis vs.
11.4 % of GHPs in the noncirrhotic population.
Recurrence after several endoscopic resection
Of the 74 recurrent GHPs, 43 were re-treated endoscopically. Of these, six were lost
to follow-up. A recurrence frequency of 78.4 % (29/37) was reported after endoscopic
resection of the first recurrence. After a third resection, without taking into account
the large number of patients lost to follow-up, this proportion reached 88.9 % (8/9).
Risk factors for neoplastic transformation
Data were missing for one GHP. Of the 144 GHPs, 15 showed neoplastic transformation,
with dysplastic or carcinomatous tissue found during their work-up, representing a
percentage of 10.4 % (95 %CI 6.2 – 16.9). Low grade dysplasia was observed in 12 GHPs,
high grade dysplasia in 2, and adenocarcinoma in 1 GHP; these latter 3 GHPs measured
≥ 50 mm. It should be noted that before therapeutic endoscopy, 10 of these polyps
had been biopsied and 50.0 % of them did not reveal any neoplastic tissue. Finally,
7 of the 15 GHPs (46.7 %) with neoplasia recurred after resection. Of these, two retained
low grade dysplasia and one had progressed to adenocarcinoma (initially low grade
dysplasia before resection). Furthermore, neoplastic transformation appeared in six
recurrent GHPs that were non-neoplastic at the histological examination of the initial
resection.
Univariate analyses found that age > 65 years, gastric intestinal metaplasia, no PPI
intake, and GHP size > 25 mm were associated with neoplastic transformation. The median
size of GHP containing neoplasia was 40.0 mm (IQR 17.0 – 55.0) compared with 15.0 mm
(IQR 10.0 – 25.0) for those without any neoplastic component. The occurrence of neoplastic
transformation was significantly higher in GHPs > 25.0 mm than in those ≤ 25.0 mm
(28.6 % vs. 4.6 %; OR 8.24, 95 %CI 2.59 – 26.26; P < 0.001) ([Table 3]). The proportion of GHPs with neoplastic transformation reached 58.3 % in GHPs > 40 mm.
Multivariate analysis after backward selection found that gastric intestinal metaplasia
(OR 5.93, 95 %CI 1.56 – 22.47; P = 0.01) and GHP size > 25.0 mm (OR 10.24, 95 %CI 2.71 – 38.69; P < 0.001) remained significantly associated with neoplastic transformation ([Table 4]).
Table 3
Risk factors of neoplastic changes in univariate analysis.
|
Neoplastic transformation[1]
|
Univariate analysis
|
|
No n = 129
|
Yes n = 15
|
OR (95 %CI)
|
P
|
|
Age
|
|
|
65.01 (11.61)
|
69.08 (6.44)
|
|
|
|
|
60 (95.2)
|
3 (4.8)
|
|
|
|
|
69 (85.2)
|
12 (14.8)
|
3.48 (0.94 – 12.91)
|
0.04
|
|
Sex, n (%)
|
|
|
80 (90.9)
|
8 (9.1)
|
0.69 (0.23 – 2.01)
|
0.49
|
|
|
48 (87.3)
|
7 (12.7)
|
|
|
|
|
1
|
0
|
|
|
|
Cirrhosis, n (%)
|
|
|
27 (93.1)
|
2 (6.9)
|
0.58 (0.12 – 2.71)
|
0.46
|
|
|
101 (88.6)
|
13 (11.4)
|
|
|
|
|
1
|
0
|
|
|
|
H. pylori Infection, n (%)
|
|
|
14 (77.8)
|
4 (22.2)
|
3.14 (0.87 – 11.37)
|
0.10
|
|
|
110 (91.7)
|
10 (8.3)
|
|
|
|
|
5
|
1
|
|
|
|
Gastritis, n (%)
|
|
|
93 (88.6)
|
12 (11.4)
|
2.00 (0.42 – 9.43)
|
0.35
|
|
|
31 (93.9)
|
2 (6.1)
|
|
|
|
|
5
|
1
|
|
|
|
Gastric IM, n (%)
|
|
|
33 (80.5)
|
8 (19.5)
|
4.22 (1.29 – 13.82)
|
0.02
|
|
|
87 (94.6)
|
5 (5.4)
|
|
|
|
|
7
|
2
|
|
|
|
Gastric atrophy, n (%)
|
|
|
28 (84.8)
|
5 (15.2)
|
2.05 (0.62 – 6.78)
|
0.25
|
|
|
92 (92.0)
|
8 (8.0)
|
|
|
|
|
9
|
2
|
|
|
|
PPI intake, n (%)
|
|
|
90 (93.8)
|
6 (6.2)
|
0.32 (0.10 – 0.98)
|
0.04
|
|
|
38 (82.6)
|
8 (17.4)
|
|
|
|
|
1
|
1
|
|
|
|
NSAID or aspirin intake, n (%)
|
|
|
28 (90.3)
|
3 (9.7)
|
1.01 (0.26 – 3.91)
|
0.99
|
|
|
94 (90.4)
|
10 (9.6)
|
|
|
|
|
7
|
2
|
|
|
|
GHP size
|
|
|
15.0 (10.0 – 25.0)
|
40.0 (17.0 – 55.0)
|
|
|
|
|
103 (95.4)
|
5 (4.6)
|
|
|
|
|
25 (71.4)
|
10 (28.6)
|
8.24 (2.59 – 26.26)
|
< 0.001
|
|
|
1
|
0
|
|
|
|
Location, n (%)
|
|
|
89 (92.7)
|
7 (7.3)
|
|
|
|
|
40 (83.3)
|
8 (16.7)
|
2.54 (0.86 – 7.49)
|
0.99
|
OR, odds ratio; CI, confidence interval; SD, standard deviation; IM, intestinal metaplasia;
PPI, proton-pump inhibitor; NSAID, nonsteroidal anti-inflammatory drug; GHP, gastric
hyperplastic polyps; IQR, interquartile range.
1 Data were missing for one GHP.
Table 4
Risk factors of neoplastic changes in multivariate analysis after backward selection.
|
OR (95 %CI)
|
P
|
|
Gastric intestinal metaplasia (yes)
|
5.93 (1.56 – 22.47)
|
0.01
|
|
Size of GHP (> 25 mm)
|
10.24 (2.71 – 38.69)
|
< 0.001
|
OR, odds ratio; CI, confidence interval; GHP, gastric hyperplastic polyp.
En bloc and R0 resection
At the first endoscopy, the proportion of en bloc resections was 86.7 %. After considering
specimen fragmentation (12.9 %) and final histological analysis, an endoscopic R0
resection was obtained in 75.5 % of cases. The mean size of the resected GHPs was
40.2 mm (SD 39.4) when treated with ESD, 17.9 mm (SD 10.6) with EMR, and 38.9 mm (SD
23.7) with the hybrid procedure (P < 0.001). There was no significant difference in the rate of en bloc resection when
using ESD (96.1 %), EMR (85.4 %) or a hybrid technique (71.4 %) (P = 0.12). Similarly, the R0 resection rate did not differ significantly according
to the endoscopy technique used (ESD 76.9 %, EMR 76.4 %, and hybrid 57.1 %; P = 0.53).
Adverse events
The only adverse event recorded was digestive bleeding: 3 (11.5 %) in the ESD group,
5 (4.5 %) in the EMR group, and none in the hybrid technique group. No gastric perforations
or deaths occurred. As the occurrence of adverse events was very low, no comparative
analysis was carried out.
Discussion
The present study showed local recurrence in more than half of GHPs ≥ 10 mm after
endoscopic resection. To our knowledge, this study represents the largest European
cohort of stomach supra-centimetric hyperplastic polyps in which the proportion of
GHP recurrence following endoscopic resection has been investigated. Surprisingly,
GHP recurrence occurred even when the initial lesion underwent en bloc and R0 resection.
In contrast with other digestive neoplasia, R0 resection does not seem to protect
against the risk of local recurrence. Moreover, unlike the observations reported for
gastric adenomas and early gastric cancer, the present study showed that ESD does
not seem to offer a benefit over piecemeal EMR [17]
[18]. Furthermore, the occurrence of profuse recurrence (i. e. more extensive than the
initial lesion) suggests that these lesions are partly related to an exuberant wound
healing process [16]. Medical history of liver cirrhosis was the only risk factor for recurrence. It
has been shown previously that cirrhosis is a risk factor for the development of GHPs
[8], possibly related to portal hypertension [19]. However, the notion of increased risk of recurrence after resection in patients
with cirrhosis is novel and should probably be considered in order to limit endoscopic
treatment in this population. Conversely, when resection has been performed, systematic
follow-up should be proposed to patients with cirrhosis in order to detect recurrence
or metachronous GHPs; this follow-up could be performed, for example, during variceal
evaluation surveillance.
The study showed that GHP recurrence was much more frequent in the antrum than in
the corpus, although antral location did not remain significantly associated with
the risk of recurrence in multivariate analysis. This could be explained by a lack
of power of the study; therefore, the impact of location of GHP recurrence should
be considered in future studies. One of the possible hypotheses for taking into account
GHP location is that the mucosal trauma induced by contractions of the antrum or duodenogastric
reflux could promote the hyperplastic wound healing process [20]. Recurrent lesions can be treated by endoscopic resection despite the presence of
submucosal fibrosis; however, the proportion of recurrence gradually increases with
the number of repeat resections, supporting the notion that recurrence is induced,
at least in part, by the iteration of the wound healing process. In any case, the
mechanism of recurrence remains unclear; for example, are there any precursor abnormalities
in the submucosa or the surrounding mucosa that could explain GHP recurrence? As the
etiology of recurrence remains unclear, long term follow-up seems necessary in order
to detect and treat recurrences to prevent a poor outcome (i. e. a larger recurrent
lesion and/or neoplastic changes). However, the presence of a neoplastic component
in 10 % of GHPs does not favor a watchful waiting strategy for all cases. It is important
to note that the majority of neoplastic polyps contained low grade dysplasia and that
high grade dysplasia or early adenocarcinomas were found in only 2.1 % of cases (in
GHPs measuring ≥ 50 mm) compared with 6.2 % of GHPs > 10 mm in the cohort of Han et
al. [12]. The neoplastic progression sequence in GHPs is poorly known and extrapolating the
Correa cascade [21]
[22] to these lesions would be premature. Nevertheless, in the current study, the presence
of intestinal metaplasia emerged as a risk factor for neoplastic transformation of
GHPs, as previously demonstrated [21]
[22]. The relationship between polyp size and risk of neoplastic transformation had already
been demonstrated by others [12]
[13], with 5.2 % of neoplastic transformations in all GHPs vs. 8.3 % in those > 10 mm
[12]. We were able to identify a threshold of 25 mm, above which the risk of neoplastic
transformation became unacceptable. According to our pathologist’s experience, the
diagnosis of low grade dysplasia is not easy, particularly for polyps with an ulcerative
component. Distinguishing low grade dysplasia from common dystrophy or inflammation
can be very difficult. Therefore, it is possible that some GHPs with low grade dysplasia
were false positives, which could explain the larger proportion of dysplastic component
observed in this study compared with other studies. Furthermore, in the present study,
the sizes of high risk GHPs (with high grade dysplasia or adenocarinoma) ranged from
50 mm to 200 mm. These last two points suggest that resection of GHPs could be performed
on a size-dependent basis, but further prospective studies are needed to validate
this hypothesis. At the first follow-up endoscopy, almost half of GHPs with neoplasia
had recurred, two of them still had dysplasia, and one had progressed to invasive
adenocarcinoma, demonstrating an unusual risk of neoplasia in recurrent lesions despite
complete initial resection. The risk of neoplastic transformation of GHPs is low but
difficult to predict based on their endoscopic aspect. Indeed, the biopsies performed
on polyps detected neoplastic foci in only half of GHP cases with dysplasia. In the
absence of endoscopic criteria to predict malignant transformation, an alternative
option could be to perform biopsies of the GHPs before considering resection.
While resection is indicated for all patients with clinical manifestations, resection
of asymptomatic hyperplastic polyps is more questionable. Indeed, the risk – benefit
balance does not seem to favor resection in the case of polyps containing no dysplasia.
It is even more surprising to note that neoplasia appeared in six local recurrences
despite no dysplasia found in the initial lesion, indicating that neoplastic transformation
might be induced by the healing process. These findings do not support the systematic
resection of polyps ≥ 10 mm but instead favor a tailored approach in which the risk
of neoplasia and the risk of local recurrence is assessed for each patient. Lesions
containing dysplasia on biopsies, or those ˃25 mm, or developing on diffuse intestinal
metaplasia should be resected, while lesions without these elements, particularly
in patients with cirrhosis, should be monitored by repeated endoscopies with biopsies
to detect neoplastic progression as early as possible ([Fig. 3]).
Fig. 3 Suggested algorithm for the management of gastric hyperplastic polyps ≥ 10 mm.
All these results need to be put into perspective. The present study shows some biases
associated with the retrospective design, mainly due to missing data. Moreover, one
of the main biases concerns the endoscopic follow-up of patients. Indeed, the time
to first follow-up endoscopy was highly variable, ranging from 3 months to more than
81 months. Furthermore, the majority of patients underwent only one follow-up endoscopy,
whereas others had up to five. In addition, the diagnosis of polyp recurrence in itself
can be considered a bias. Although a recurrence was defined as a GHP developing at
the resection site, including on the resection scar if present, it is possible that
a number of de novo GHPs were mistakenly considered as recurrent lesions, owing to
close proximity, a faded scar, or evaluation by another endoscopist. Finally, the
study does not define a follow-up protocol after endoscopic resection. A prospective
cohort study seems warranted to confirm these results and better define the recurrence
timing and patterns. Further studies concerning the management of recurrence are needed
to compare a systematic resection of recurrences with a long-term follow-up strategy
using biopsy samples to resect only neoplastic recurrent lesions.
In conclusion, GHPs are a very different entity from gastric adenomas and should be
managed differently. The risk of neoplastic change is significantly increased for
lesions > 25 mm, with a risk of high grade dysplasia and cancer appearing in lesions
≥ 50 mm. The risk of recurrence is high, particularly in patients with cirrhosis,
and long term follow-up is recommended in these patients.