Abstract 3583
Background
Tumor Associated Macrophages (TAMs) and ARF-MDM2 pathway seem to be interconnected actors in malignant pleural mesothelioma (MPM) pathogenesis, treatment outcome and prognosis. On the basis of such evidence, this prospective study aims at comparing tumor immune microenvironment (TME) and checkpoint expression (PD-L1) in naïve tumor samples and immune cells in blood samples of ARF+ vs. ARF- MPM.
Methods
Tumor samples were collected at the baseline (T0) in all enrolled patients and at the time of surgery (T1) in resectable patients. Immunohistochemistry was carried out to evaluate p14/ARF, PD-L1, CD3+, CD4+, CD8+ T lymphocytes; CD20+ B-lymphocytes; CD68+ macrophages. Blood samples were collected in a subset of patients at T0 and T1 and analyzed for CD3+CD4+, CD3+CD8+, CD4+CD25+FoxP3+ peripheral T lymphocytes, CD68 + (total) and CD163 + (M2-like) peripheral monocytes by flow cytometry analysis.
Results
Preliminary data on the first 52 chemonaive MPM samples (32 epithelioid, 16 biphasic and 4 sarcomatoid) were evaluated. P14/ARF was detected in 11 patients (21%). P14/ARF+ cases were characterized by higher CD4+ T-lymphocyte percentage (median value 10% vs 1%, p = 0.05), mainly in peritumoral areas, while p14/ARF – cases were characterized by higher CD163+ M2 macrophages percentage (50% vs 40% in p14/ARF+ cases) and higher CD163+/CD68+ ratio (1.3 vs. 1 in p14/ARF+ cases), even though without statistical significance. Paired (T0 and T1) blood samples of five patients were also assessed for CD8+ and CD4+CD25+FoxP3+ T-reg lymphocytes levels change before and after chemotherapy. We observed a T-reg decrease in 2 patients achieving a disease control to first-line platinum-based chemotherapy, while an increase in 3 progressing patients, without major difference between p14/ARF + and p14/ARF- cases.
Conclusions
p14ARF+ MPM samples seem to be characterized by lower CD163+ M2-polarized macrophages and higher CD4+ T lymphocytes. The amount of T-reg in blood samples may be useful to anticipate radiological and/or clinical progression to chemotherapy. Larger case series and wider TME characterization in tissue and immune cells quantification in blood samples are needed to validate our preliminary findings and will be presented at the conference.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Istituto Oncologico Veneto IRCCS.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
5519 - Is there a difference of Palliative care problems and needs between cancer and non-cancer hospitalized elderly patients?
Presenter: Ioanna Chatzi
Session: Poster Display session 1
Resources:
Abstract
2505 - There is a lack of clinical research for patients with cancer in palliative care
Presenter: Marie Vinches
Session: Poster Display session 1
Resources:
Abstract
5273 - Specialist Palliative Care (SPC) in Haematological Malignancy: Establishing practices in a UK Tertiary Cancer Centre (TCC)
Presenter: Emma Kedgley
Session: Poster Display session 1
Resources:
Abstract
5864 - Evaluation of the relationship between the attachment styles and psychological resilience of cancer patients receiving chemotherapy
Presenter: Fatma Bugdayci Basal
Session: Poster Display session 1
Resources:
Abstract
770 - Gefitinib along with Methotrexate as palliative therapy in PS 3 and above in metastatic squamous cell carcinoma head and neck cancer patients
Presenter: Vidya Dusi
Session: Poster Display session 1
Resources:
Abstract
4232 - High intensity end-of-life care in pediatrics, adolescent and young adult patients with cancer using an administrative database.
Presenter: Seiko Bun
Session: Poster Display session 1
Resources:
Abstract
4845 - Embedded outpatient palliative care service within the oncology clinic: Preliminary experience in Hacettepe Oncology Hospital
Presenter: Deniz Can Guven
Session: Poster Display session 1
Resources:
Abstract
3270 - Internet-based stepped care for individuals with cancer and concurrent anxiety or depression symptoms – results from a randomized controlled trial
Presenter: Birgitta Johansson
Session: Poster Display session 1
Resources:
Abstract
5503 - Impact of Cognitive-Behavioral-Therapy (CBT) on levels of anxiety, depression and distress in cancer patients (pts)
Presenter: Daniela Tregnago
Session: Poster Display session 1
Resources:
Abstract
5553 - Cytokine genetic variations and worse quality of life among family caregivers of head and neck cancer patients in palliative care
Presenter: Daniel Pequeno
Session: Poster Display session 1
Resources:
Abstract