FOXP3 and carcinoma of esophagus: Conversely, increased infiltration of FoxP3+ Tregs was found to be associated with improved OS in colorectal (OR 0.71, 95% CI 0.62 to 0.82, P = 0.01), head and neck (OR 0.69, 95% CI 0.50 to 0.95, P = 0.024), and oesophageal cancer (OR 0.51, 95% CI 0.33 to 0.79, P = 0.002).