Tumor lymphocytic infiltration in non-small cell lung cancer: the ultimate prognostic marker?

Lung cancer is still the leading cause of death worldwide despite recent improvements in early diagnosis and treatment. Only about 20–25% of patients are resectable at the time of diagnosis (stage I–IIIA), but clinical outcomes vary among the same TNM stage. The high recurrence rate has prompted many authors to look for new biomarkers to identify patients who can benefit from adjuvant therapies.