ECP 2017 - Abstract Book

PD-L1 and PD-1 expression were observed in 12.5 % (24/192) and

88.8 % (167/188) of the cases, respectively. The majority of tumours were

T3 (79.8 %), N1 (40.1 %) and M0 (90.6 %) while lymphovascular and

perineural invasion and tumour budding were observed in 74.1 , 65.5 and

16.8 % of the tumours, respectively. PD-L1 expression in TILs signifi-

cantly correlated with M1-stage (

= 0.042) whereas PD-1 expression in

TILs significantly correlated with perineural invasion (

= 0.002). Cases

with PD-L1 expression presented with a better median overall survival of

69.4 ± 16.7 months compared to PD-L1 negative tumours with a survival

of 19.8 ± 2.5 months (

= 0.0058).

Conclusion:

Our results suggest that PD-L1 expression in gastric carci-

nomas may be associated with favorable tumour prognosis and that tu-

mour microenvironment including TILs should be routinely evaluated.

OFP-11-013

Olfactomedin 4 (OLFM4) expression predicts nodal status in patients

with oesophageal adenocarcinoma

L. Suzuki

, F. ten Kate, H. Stoop, M. Doukas, J. van Lanschot, B.

Wijnhoven, L. Looijenga, K. Biermann

Erasmus MC, Dept. of Pathology, Rotterdam, The Netherlands

Objective:

Endoscopic surgery is increasingly applied for early esopha-

geal adenocarcinoma (EAC) without lymph node metastasis (LNM).

OLFM4, an intestinal stem cell marker, is correlated with metastasis in

a variety of cancers. This study investigates the predictive value of

OLFM4 for LNM in EAC.

Method:

OLFM4 expression was evaluated immunohistochemically in

115 patients with advanced (pT2 or higher) EAC, treated by esophagec-

tomy alone in which at least 12 lymph nodes where retrieved (pN0

= 24

vs. pN+

= 91). Clinicopathological factors and low (defined as less than

30 % positive tumour cells) OLFM4 expression were subjected to logistic

regression and Cox regression analysis to assess prognostic value.

Results:

Low OLFM4 expression correlated with tumour grade

(

= 0.01), LNM (

= 0.023), and recurrence (

= 0.019). Furthermore,

lowOLFM4 (OR 3.08, 95%CI 1.04-9.14,

= 0.043) was identified as an

independent predictive factor for LNM in EAC. However, OLFM4 was

not predictive for overall or disease free survival.

Conclusion:

Loss of OLFM4 expression is independently predictive for

LNM in advanced EAC, but not for survival. Further studies on endo-

scopically treatable early EAC are required to evaluate the potential value

of OLFM4 for risk stratification of patients suitable for endoscopic vs.

conventional surgery.

OFP-11-014

Tumour-budding evaluated on cytokeratin stained sections in stage II

colon cancer patients, a population based study

S. Kjaer-Frifeldt

, J. Lindebjerg, F. B. Sørensen, A. K. M. Jakobsen,

DCCG.dk

Vejle Sygehus, Klinisk Patologi, Denmark

Objective:

Tumour-budding denotes the detachment tumour cells from

the adenocarcinoma bulk, either individually or gathered in small aggre-

gates (max. 5 cells). Several studies have stated the prognostic value of

tumour-budding in patients with colorectal cancer. Upcoming guidelines

base scoring of tumour-budding on HE sections, despite a well-known

fragility of the reproducibility.

Method:

The study included all patients (

= 589) diagnosed with

stage II colon cancer in Denmark in 2003. Tumour-budding was

defined as the presence of at least 10 buds at ×200 magnification,

using a paired set of HE and Cytokeratin-20 stained sections from

each case. Results were evaluated regarding Recurrence-Free

Cancer Specific Survival (RF-CSS) and Time-To-Recurrence

(TTR).

Results:

By the use of CK-20, an additional 66 patients (146 in total)

were classified with budding compared to the 80 patients identified, using

HE sections. Patients with tumours displaying tumour-budding by CK-20

had a significant worse prognosis of RF-CSS and TTR in both univariate

(RF-CSS: HR = 1.94 (1.27

–

2.96),

= 0.0009; TTR: HR = 2.31 (1.39

–

3.84),

= 0.0004), and multiple COX-analyses (RF-CSS: HR = 2.51

(1.64

–

3.83),

< 10-5; TTR: HR = 2.87 (1.71

–

4.80),

= 0.0001).

Conclusion:

Immunohistochemistry enhances detection of tumour-

budding compared to HE-sections, and provides improved prognostic

impact in stage II colon cancer patients.

OFP-11-015

MicroRNA-21 expression in budding colon cancer cells

—

multiplex

stained slides analysed by confocal scanning microscopy

B. Nielsen

, K. Knudsen, J. Lindebjerg, A. Kalmár, B. Molnár, F.

Sørensen, T. Hansen

Bioneer A/S, Molecular Histology, Horsholm, Denmark

Objective:

Expression of microRNA-21 (miR-21) in stromal fibroblastic

cells in colorectal cancers is well documented, whereas miR-21 expres-

sion in tumour budding cells is poorly described. Budding tumour cells

possess increased metastatic properties and characteristics of epithelial to

mesenchymal transition.

Method:

To characterize miR-21 budding cells, we first developed a

multiplex fluorescence staining method by combining miR-21 in situ

hybridization with immunohistochemical staining for cytokeratin and

laminin-gamma2, and stained 20 colon cancer cases (stage II,

= 7, stage

III,

= 13). We then employed a confocal scanning microscope to obtain

digital images covering the invasive front.

Results:

The high resolution of the confocal digital images allowed de-

tailed examination of the 4-fluorophore-stained slides e.g. in the discrim-

ination of epithelial cells from adjacent stromal cells. Five out of 16

successfully processed cases had more than 10 % miR-21 positive bud-

ding cells and were all stage III cancers, and generally laminin-gamma2

negative. The presence of miR-21 in the tumour budding cells was not

associated with the level of tumour budding.

Conclusion:

These observations suggest that the miR-21 expression in

tumour budding cells increases with cancer progression and is indepen-

dent of laminin-gamma2. The confocal digital images were crucial for

unambiguous examination of the complex staining patterns.

OFP-12-001

Expression of DcR3 in lung adenocarcinoma: Clinicopathological

correlation with 461 cases

W.-C. Chang

MacKay Memorial Hospital, Dept. of Pathology, Taipei, Taiwan

Objective:

Decoy receptor 3 (DcR3) has been reported to be expressed in

many malignant tumours. However, the role of DcR3 expression in lung

cancer, particularly adenocarcinoma, has not been well studied in the past.

In this study, we sought to investigate the expression profile and the clin-

icopathological implications of DcR3 expression in lung adenocarcinoma.

Method:

Immunohistochemistry was used to examine DcR3 expression

in lung adenocarcinoma tissue (

= 461). The differences in DcR3 ex-

pression among the various histopathologic patterns were analyzed. The

relationship between DcR3 expression and clinicopathological

Wednesday, 6 September 2017, 08:30

–

12:00, Emerald Room

OFP-12 Joint Session: Pulmonary Pathology / Thymic and

Mediastinal Pathology

Virchows Arch

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2017

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Suppl 1

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