Immunoarchitectural Pattern and Its Potential Prognostic Value in Mucoepidermoid Carcinoma

Area of Science:

• Oncology
• Immunology
• Pathology

Background:

• Salivary gland mucoepidermoid carcinoma (MEC) is a complex malignancy.
• Understanding its immune microenvironment is crucial for treatment strategies.

Purpose of the Study:

• To define tumor immunoarchitectural patterns (IPs) in MEC.
• To characterize the immune profile and its prognostic significance.
• To explore implications for immunotherapy.

Main Methods:

• Analysis of 41 MEC cases using whole-slide imaging and AI-assisted assessment.
• Evaluation of tumor immunoarchitectural patterns and tumor-infiltrating lymphocyte (TIL) parameters.
• Immunohistochemistry for CD3 and CD8 markers to assess lymphocyte subpopulations.

Main Results:

• Immune-rich (I-rich) tumors showed high TIL density, associated with aggressive behavior, especially in high-grade MEC.
• Increased TIL density in the inner invasive margin correlated with poorer disease-free survival (DFS).
• Aggressive MEC cases had heterogeneous TIL profiles, but no specific TIL pattern significantly impacted DFS.

Conclusions:

• MEC exhibits high immunogenicity, but the protective role of CD8+ T lymphocytes is not prominent.
• I-rich tumors are linked to more aggressive disease and unfavorable outcomes.
• Investigating TILs in the invasive margin may reveal new immunotherapy targets.