The tumor microenvironment of benign and malignant salivary gland tumors.

Authors :: Wai KC
Okholm TLH
Ha PK
Marquez DM
Tenvooren I
Jones KB
Spitzer MH
Source :: Head & neck [Head Neck] 2024 Jul; Vol. 46 (7), pp. 1625-1636. Date of Electronic Publication: 2024 Mar 07.
Publication Year :: 2024
Abstract: Background: Treatment of salivary gland tumors (SGTs) remains challenging. Little is known about the immune landscape of SGTs. We aimed to characterize the tumor microenvironment in benign and malignant SGTs.<br />Methods: Eleven benign and nine malignant tumors were collected from patients undergoing curative intent surgery. Specimens were analyzed using mass cytometry by time-of-flight. Immune cell populations were manually gated, and T cells were clustered using the FlowSOM algorithm. Population frequencies were compared between high-grade and low-grade malignancies, corrected for multiple hypothesis testing.<br />Results: There were trends towards increased CD4+ and CD8+ T cells among malignant tumors. High-grade malignancies exhibited trends towards higher frequencies of CD8+ PD-1+ CD39+ CD103+ exhausted T cells, CD4+ FoxP3+ TCF-1+ CD127- Tregs, and CD69+ CD25- CD4+ T cells compared to low-grade malignancies.<br />Conclusion: SGTs exhibit significant immunologic diversity. High-grade malignancies tended to have greater infiltration of exhausted CD8+ T cells and Tregs, which may guide future studies for immunotherapy strategies.<br /> (© 2024 The Authors. Head & Neck published by Wiley Periodicals LLC.)