FOXP3 and carcinoma of esophagus: High FoxP3+ Tregs infiltration was significantly associated with poor prognosis in the majority of solid tumors studied; no prognostic effect of FoxP3+ Tregs were observed in ovarian, pancreatic cancers and et al.; whereas, in colorectal, head and neck, and oesophageal cancers, tumor infiltrating FoxP3+ Tregs were associated with favorable prognosis.