Review


Focus on TILs: Prognostic significance of tumor infiltrating lymphocytes in head and neck cancers

Ravindra Uppaluri1, Gavin P. Dunn2 and James S. Lewis Jr.1,3

1Department of Otolaryngology/Head and Neck Surgery and John Cochran VA Medical Center, Washington University School of Medicine, St. Louis, MO, USA

2Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA

3Department of Pathology/Immunology, Washington University School of Medicine, St. Louis, MO, USA

Keywords: human, head and neck cancer, tumor-infiltrating lymphocytes, prognosis, therapy


Abstract

The expanding and established literature that correlates tumor infiltrating lymphocytes (TILs) with outcomes of patients with solid tumors has contributed greatly to the appreciation of the interaction between the host immune system with neoplastic growth. This analysis has been limited to specific tumors, such as melanoma and ovarian cancer, and our understanding of TILs in relation to many other malignancies has yet to be explored. We review one less well studied malignancy, head and neck squamous cell carcinoma (HNSCC), and the initial attempts to examine the impact of TILs on outcomes of these patients. To provide a context for the discussion of TILs and HNSCC, we first review the epidemiology, relevant head and neck anatomy, immune responses and discuss the historical data regarding the unique immunobiology of these tumors. Finally, with this perspective, we describe our current understanding of tumor infiltrating lymphocyte data for head and neck cancers.