# Immunotherapy in thymic epithelial tumors: tissue predictive biomarkers for immune checkpoint inhibitors

## TL;DR

This paper discusses the use of immunotherapy in thymic epithelial tumors and the role of tissue biomarkers in predicting treatment response.

## Contribution

The paper highlights the evaluation of tissue biomarkers for immune checkpoint inhibitors in thymic epithelial tumors.

## Key findings

- Immune checkpoint inhibitors are being evaluated for advanced thymic epithelial tumors.
- PD-L1 and other biomarkers are being studied to predict response to immunotherapy.
- Low tumor mutation burden and immune-related adverse events pose challenges in treatment.

## Abstract

Thymic epithelial tumors (TETs) are rare malignant neoplasms arising in the thymus gland. Nevertheless, TETs, including thymomas (TMs), thymic carcinomas (TCs), and thymic neuroendocrine neoplasms (TNENs), are the most common mediastinal malignancies overall. A multidisciplinary approach is required for the appropriate diagnostic and therapeutic management of TETs. To date, the main therapeutic strategies are largely depended on the stage of the tumor and they include surgery with or without neoadjuvant or adjuvant therapy, represented by platinum-based chemotherapy, radiotherapy or chemoradiotherapy. Immune checkpoint inhibitors (ICIs) are ongoing under evaluation in the advanced or metastatic diseases despite the challenges related to the very low tumor mutation burden (TMB) and the high incidence of immune-related adverse events in TETs. In this regard, predictive impact of tissue biomarkers expression such as programmed cell death ligand-1 (PD-L1), and other emerging biomarkers, as well as their optimal and shared interpretation are currently under evaluation in order to predict response rates to ICIs in TETs.