190 / 366
PS-13-001
Gastric carcinoma with lymphoid stroma: Analysis of microsatellite
instability and Epstein-Barr virus status
J. Ribeiro
*
, D. Montezuma, A. Pires-Luís, P. Lopes, H. Sousa, L. Afonso,
R. Henrique
*
IPO - Porto, Molec.Onc. & Viral Pat. Group, Portugal
Objective:
Analyze microsatellite instability (MSI) and Epstein-Barr vi-
rus (EBV) status in gastric carcinoma with lymphoid stroma (GCLS), and
characterize its clinicopathological features.
Method:
GCLS cases were retrieved from the archives and reviewed by an
experienced dedicated gastrointestinal pathologist. Expression of EBV
encoded small RNA (EBER) by in situ hybridization and MSI status were
assessed in 18 cases of GCLS diagnosed between 2000 and 2017. MSI status
was evaluated by MLH1, MSH2, MSH6 and PMS-2 immunoexpression.
Relevant clinical data was collected from patients
’
charts.
Results:
GCLS was more prevalent in men (61.1 %) and in proximal lesser
gastric curvature (55.5 %) with a mean age of 60.7 years. During follow-up
one patient presented metastasis and died from disease. Diffuse positivity for
EBV hybridization was observed in 13 (72.2 %) GCLS, whereas weak and
focal positivity was detected in 3 (16.6 %) cases. Loss of MLH1 and PMS2,
indicating altered expression of MLH1, was found in 2 (11.1 %) cases, one of
them with simultaneous weak and focal EBER expression.
Conclusion:
The global characteristics of this series are in accordance
with previous publications. Although EBV infection and MSI, considered
the two main carcinogenic pathways involved in GCLS, have been con-
sidered mutually exclusive, our results suggest that some cases might
share both features.
PS-13-002
Histopathological evaluation of gastric polypoid lesions: A single in-
stitutional study
E. Gün
*
, F. H. Dilek, E. Cakir, D. O. Buyuktalanci, A. Avci, S. Vatansever
*
Izmir Katip Celebi University, Pathology, Turkey
Objective:
To identify the prevalance and characteristics of the gastric
polypoid lesions detected by endoscopy.
Method:
The records of 45270 patients who underwent endoscopy be-
tween January 2007 and March 2017 were reviewed retrospectively. The
patients with gastric polypoid lesions were evaluated in terms of age,
gender, histopathological diagnosis and anatomical location.
Results:
A total of 996 (%2.2) patients were found to have at least one
polypoid lesion whereas 214 patients had 2 or more. Of all 1209 lesions,
19.2 % were neoplastic and 80.8 % were non-neoplastic lesions.
Hyperplastic polyp was the most common (58.6 %) followed by foveolar
hyperplasia (17.4 %), fundic gland polyp (11.5 %) and well-differentiated
neuroendocrine tumour (4.7 %). Adenomatous and inflammatory fibroid
polyps (2.2 %) were less common. H.pylori incidence in hyperplastic
polyps was 27.7 %. The most common anatomical location was the an-
trum (42.5 %). The mean age was 60.3 and female to male ratio was 1.59.
Focal dysplastic changes were seen in 1.6 % of hyperplastic polyps and
0.5 % showed adenocarcinoma within the polyp.
Conclusion:
Gastric polypoid lesions are common endoscopical findings
and histopathological diagnosis should be made carefully since there is a
variety of lesions that can present as polyps. The dysplastic changes and
malignant transformation in hyperplastic and adenomatous polyps should
be kept in mind.
PS-13-003
Endoscopical submucosal dissection of leiomyomas in the oesophagus:
7 cases
E. Gün
*
, N. Ekinci, D. O. Buyuktalanci, F. H. Dilek, B. B. Kucukzeybek,
F. Aslan
*
Izmir Katip Celebi University, Pathology, Turkey
Objective:
Endoscopical submucosal dissection (ESD) is being used
more frequently in recent years for en bloc resection of large gastric and
colonic tumours and now for the removal of esophageal tumours. Here,
we report a case series of esophagial tumours resected by ESD all of
which were diagnosed as leiomyomas.
Method:
The records of patients who underwent ESD for esophagial
lesions between 2014 and 2016 were retrieved and seven cases of
esophagial smooth muscle tumours were found. The cases were then
evaluated depending on gender, localisation, size and immunohistochem-
ical profile.
Results:
Five of the patients were female whereas 2 were male. The
median age was 58 years (range 39
–
62 years). The locations of all
tumours were in the lower 1/3 portion of the oesophagus. The largest
tumour had a diameter of 4.5 cm, the mean tumour size was 2.7 cm
and the cut surface was solid and grey in all. Microscopically, the
tumours were made of fascicles of spindle cells with no atypia and
mitosis. Immunohistochemical studies showed diffuse positivity for
smooth muscle actin and desmin and negativity for CD117 and
CD34 in all of the cases. Six of the cases were negative for S-100
protein whereas one case showed focal weak positivity. The Ki-67
index was <1 % and complete resection was achieved in all of the
tumours.
Conclusion:
ESD is a safe and effective procedure for treating esoph-
ageal tumours and complete resection is possible in experienced
hands.
PS-13-004
Study of a metastatic colon cancer model to the liver: Clinicopathological
results
A. Alonso Fernández-Velasco
*
, R. Ugalde Herrá, M. P. González
Gutiérrez, M. González Guerrero, I. Husain Calzada, I. Fernández Vega
*
Hospital Universitario Central de Asturias, Avilés, Spain
Objective:
This study aimed to analyze clinicopathological features of 57
patients that developed adenocarcinomas in the colon with progression to
liver metastasis.
Method:
Fifty-seven colon adenocarcinomas (CA) and their respective
hepatic metastatic adenocarcinomas (MA) were microscopically exam-
ined. Diverse histological parameters such us necrosis, mitotic activity,
grade of differentiation, inflammation, tumour buds
…
were analyzed.
Clinical data such as survival rates and demographic parameters were
also recollected.
Results:
Our database is composed of 38 men and 19 women with a mean
age of 66.2 ± 9.6 years. About 79 % of cases were from the left colon.
Histopathologically, almost 89 % CA presented tumour buds and almost
52 % showed metastatic regional lymph nodes on diagnosis. The
tumoural grade was higher in CA (1.8/3 in CA vs 1.6/3 in MA); mitotic
activity per 10HPF was almost equal (35 ± 22 in CA vs 34 ± 20 in MA);
intratumoural necrosis was significantly higher in MA (3.6/4 in MA vs
2.0/4 in CA). Minimal differences were observed concerning
peritumoural chronic inflammation (1.3/4 in CA vs 1.2/4 in MA) .
Statisticlally, presence of tumour buds in CA correlated with lower
progression-free survival (
p
= 0.013).
Conclusion:
We have described relevant histopathological differences be-
tween CA and MA. Tumour buds in CA correlated with lower progression-
time survival.
Tuesday, 5 September 2017, 09:30
–
10:30, Hall 3
PS-13 Digestive Diseases Pathology - GI
Virchows Arch
(
2017
)
471
(
Suppl 1
):
S1
–
S352
S176