Abstract 3982
Background
A special role in the tumour progression is played by heterogeneous components of the microenvironment of tumours, premetastatic tumour niches, influencing which seems likely to change the disease course. Our purpose was to analyze some characteristics of the local cellular immunity in metastatic GC.
Methods
33 GC patients aged 30-80 years were divided into 2 groups: group 1 – M0, non-metastatic GC, n = 17, mean age 61.7±8.9 years (G2 – 11, G3 – 6 patients); group 2 – M1, GC with peritoneal and omentum metastases, n = 16, mean age 58.7±11.5 years (G2 – 7, G3 – 5, G4 - 3 patients). Tumours (T), peritumoral tissues (PT), omentum (O) and peritoneum (P) tissues were studied. Lymphocytes were determined by flow cytometry using FACSCantoII (BD) and T-, B-, NK antibody panels; quantitative content of DN (CD3+CD4-CD8-), DP (CD3+CD4+CD8+) T lymphocytes and regulatory (T-regs) T cells (CD4+CD25+CD127dim) was studied.
Results
Patients with M1 GC demonstrated increased CD3+ lymphocytic infiltration of T, PT, O and P tissues. IRI in M1 O was significantly higher than in M0 (1.95±0.3 vs 0.7±0.2), being similar in other tissues. Levels of DN lymphocytes were lower in O of M1, compared to M0 (7.7±2.5 vs 15.7±5.6, p ≤ 0.05). Contents of NK cells, NKT lymphocytes significantly decreased in O of M1 patients, compared to M0 (3.3≤1.1 vs 14.0≤2.3 and 1.7±0.5 vs 3.8±0.8, respectively). Higher levels of NKT lymphocytes were registered in M1 PT, compared to M0 (3.3±1.1 vs 1.3±0.4), as well as lower levels of NK cells in T (2.3±0.9 vs 5.33±0.2). Percentage of Treg lymphocytes in P and O were significantly lower in M1 than in M0 (respectively, 6.9±1.5 vs 12.6±4.9 and 5.9±1.3 vs 12.6±4.9). Higher amount of B lymphocytes was registered in all tissues of M1 patients, compared to M0, maximal in O (13.1±3.3 vs 3.4±1.5), T (23.5±5.1 vs 17.2±2.3) and P (8.2±3.4 vs 3.5±1.2), while in PT it was lower (15.7±4.2 vs 43.7±4.5).
Conclusions
GC metastasis to the omentum and peritoneum is characterized by a change in their immunological features – a decrease in the tissue level of NK and NKT lymphocytes, a loss in the prevalence of CD3+CD8+ due to an increase in the number of CD3+CD4+ cells, and an increase in the level of CD19 + (B2) lymphocytes. This probably contributes to the appearance of metastatic lesions in these organs in gastric cancer.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
4732 - Progesterone Receptor Isoform Ratio Dictates Antiprogestins/Progestins Effects on Metastatic Breast Cancer Models
Presenter: Maria Abascal
Session: Poster Display session 2
Resources:
Abstract
5737 - PAM50 and CGH-array genomic characterization of HER2-Equivocal Breast Cancers defined by the 2018 ASCO/CAP recommendations.
Presenter: Carine Ngo
Session: Poster Display session 2
Resources:
Abstract
1096 - OncotypeDX® predictive nomogram for recurrence score output: a machine learning system based on quantitative immunochemistry analysis - ADAPTED01
Presenter: Fabio Marazzi
Session: Poster Display session 2
Resources:
Abstract
5426 - Geriatric parameters predict both disease-related and patient-reported outcomes in older patients with breast cancer
Presenter: Willeke van der Plas-Krijgsman
Session: Poster Display session 2
Resources:
Abstract
5865 - Patients with a 21-gene assay in South East London differ from the TAILORx trial population
Presenter: Charalampos Gousis
Session: Poster Display session 2
Resources:
Abstract
1312 - Predictive tools in adjuvant breast cancer – what is the standard of evidence supporting their utility? A literature review examining validation of Adjuvant!, Cancermath and NHS Predict
Presenter: Alice Loft
Session: Poster Display session 2
Resources:
Abstract
2445 - Oncologic outcome of invasive lobular carcinoma: Is it different from that of invasive ductal carcinoma?
Presenter: Hee Jun Choi
Session: Poster Display session 2
Resources:
Abstract
2476 - Pathologic response and survival efficacy in patients with initial nodal involvement after neoadjuvant chemotherapy in early breast cancer
Presenter: SERAFIN MORALES Murillo
Session: Poster Display session 2
Resources:
Abstract
3761 - Chemotherapy-induced amenorrhea: prognostic impact on premenopausal Egyptian patients with breast cancer
Presenter: Khaled Abdel Karim
Session: Poster Display session 2
Resources:
Abstract
4687 - Predicting the presence of breast cancer using circulating small RNA in the serum
Presenter: Yumiko Koi
Session: Poster Display session 2
Resources:
Abstract