FOXP3 and squamous cell carcinoma: Patients with adenocarcinoma had a significant lower percentage of CD4+CD25+FoxP3+ (26.22 ± 3.53%) and a numerical lower percentage of CD4+CD25highFoxP3+ (41.89 ± 3.74%) than HD (35.46 ± 6.23, p = 0.03 and 54.81 ± 5.9%, p = 0.13,respectively), whereas patients with squamous cell carcinoma had significantly higher frequencies of CD4+CD25highFoxP3+compared to patients with adenocarcinoma (57.44 ± 4.83% versus 41.89 ± 3.74%, p = 0.006; Supplementary Table S2).