Clinical Significance of Tumor-Infiltrating Lymphocytes in Lung Neoplasms

Tumor-infiltrating lymphocytes are observed in about one fourth of resected lung neoplasms: they are rare in neuroendocrine tumors. Tumor-infiltrating lymphocytes are more frequent in poorly differentiated tumors and in tumors with microscopic vascular invasion. The presence of TIL correlates with an improved survival in squamous cell carcinomas, particularly at early stage. The survival advantage increases with the duration of follow-up.