Abstract 1735P
Background
Thymic Epithelial tumors (TETs) are rare malignancies of the anterior mediastinum with a high incidence of associated autoimmune disorders (AIDs) up to 30%, being Myasthenia Gravis (MG) the most frequent. Loss of CD28 and expression of CD57, and KLRG1 have been previously identified as markers of T-cell immunosenescence. The impact of immunosenescence in patients with TETs and with AIDs is unknown.
Methods
We prospectively selected a representative set of consecutive patients (pts) suffering TETs from Gustave Roussy Center. The percentage of CD28-, CD57+, KLRG1+ among CD8+ T cells [senescent immune phenotype (SIP)] was assessed by flow cytometry on blood from patients with TETs as an exploration set. A SIP cut-off was identified by log-rank maximization method and patients with TETs reporting or not AIDs were classified accordingly.
Results
20 pts were included in the cohort. Median age at diagnosis of 48 (29-65) years. 70% were women. 40% reported AIDs with 75% of MG. Thymoma B2 was the most frequent (n=7, 35%). 60% of the pts reported advanced disease at diagnosis. 70% and 75% had history of radiotherapy (RT) or chemotherapy (CT), respectively. 39.5% was established as cut-off for SIP phenotype (SIP+). 5/20 (25%) of pts were SIP+ (≥39.5%). No clinicopathological pts characteristics were shown as independent factors for SIP+. Pts with SIP+ immune phenotype shown eleven-fold higher risk of presenting AIDs (OR:11, 95%CI [0.92-130,32; p=0.057). Indeed, pts with active AID at sample collection shown higher tend (OR:4.3, 95%CI [0.42-44.42; p=0.21). Women (OR: 2, p=0.68), previous RT (OR:1.45, p=0.71) and previous CT (OR:2, p=0.57) tend to correlate with SIP+ phenotype in our cohort. Table: 1735P
Represents the association between AIDs and SIP+
| AID | Total | |||
| Yes | No | |||
| SIP+ | Yes | 4 | 1 | 5 |
| No | 4 | 11 | 15 | |
| Total | 8 | 12 | 20 |
Conclusions
Circulating T-cell immunosenescence is observed in up to 25% of patients with TETs. Our results suggest a higher rate of autoimmunity in patients with an immunosenescence profile. Previous RT and CT may be associated to SIP+. Further analyses are expected.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Gustace Roussy Cancer Center.
Funding
Has not received any funding.
Disclosure
O. Mercier: Financial Interests, Personal and Institutional, Invited Speaker: AstraZeneca. D. Planchard: Financial Interests, Personal and Institutional, Invited Speaker, Funding: AstraZeneca; Financial Interests, Personal and Institutional, Invited Speaker, Funding: Bristol Myers Squibb; Financial Interests, Personal and Institutional, Invited Speaker, Funding: Boehringer Ingelheim; Financial Interests, Personal and Institutional, Invited Speaker, Funding: Celgene; Financial Interests, Personal and Institutional, Invited Speaker, Funding: Daiichi Sankyo; Financial Interests, Personal and Institutional, Invited Speaker, Funding: Eli Lilly; Financial Interests, Personal and Institutional, Invited Speaker, Funding: Merck; Financial Interests, Personal and Institutional, Invited Speaker, Funding: Novartis; Financial Interests, Personal and Institutional, Invited Speaker, Funding: Pfizer; Financial Interests, Personal and Institutional, Invited Speaker, Funding: prIME Oncology; Financial Interests, Personal and Institutional, Invited Speaker, Funding: Peer CME; Financial Interests, Personal and Institutional, Invited Speaker, Funding: Roche; Financial Interests, Personal and Institutional, Invited Speaker, Funding: Samsung. F. Barlesi: Financial Interests, Personal and Institutional, Invited Speaker: AstraZeneca; Financial Interests, Personal and Institutional, Invited Speaker: Bayer; Financial Interests, Personal and Institutional, Invited Speaker: Bristol Myer Squibb; Financial Interests, Personal and Institutional, Invited Speaker: Boehringer Ingelheim; Financial Interests, Personal and Institutional, Invited Speaker: Eli Lilly; Financial Interests, Personal and Institutional, Invited Speaker: Roche; Financial Interests, Personal and Institutional, Invited Speaker: Novartis; Financial Interests, Personal and Institutional, Invited Speaker: Merck; Financial Interests, Personal and Institutional, Invited Speaker: MSD; Financial Interests, Personal and Institutional, Invited Speaker: Pierre Fabre; Financial Interests, Personal and Institutional, Invited Speaker: Pfizer; Financial Interests, Personal and Institutional, Invited Speaker: Takeda. J-C. Soria: Financial Interests, Personal, Advisory Board: AstraZeneca; Financial Interests, Personal, Advisory Board: Relay Therapeutics; Financial Interests, Personal, Advisory Board: Gritstone Oncology; Financial Interests, Personal, Member of the Board of Directors: Hookipa Pharmaceutical. N. Chaput: Financial Interests, Personal and Institutional, Sponsor/Funding: AstraZeneca; Financial Interests, Personal and Institutional, Sponsor/Funding: Bristol Myers Squibb; Financial Interests, Personal and Institutional, Sponsor/Funding: GSK; Financial Interests, Personal and Institutional, Sponsor/Funding: Roche; Financial Interests, Personal and Institutional, Sponsor/Funding: Sanofi; Financial Interests, Personal and Institutional, Sponsor/Funding: Cytune Pharma. All other authors have declared no conflicts of interest.