OBJECTIVE: To investigate the correlation between the expression of tumor-associated macrophages (TAM) and tumor neovascularization, as well as their impact on the prognosis of patients with early-stage esophageal cancer (EC).

PATIENTS AND METHODS: A sample of 83 esophageal cancer (EC) patients was collected, and the expression of cancer cells, tumor-associated macrophages (TAMs), and tumor neo-vessels in the tumor tissue and its surrounding areas was quantified using a quantum dots-based immunofluorescence technique. The relationship between the expression of these components and the patients' clinical and pathological characteristics, as well as overall survival (OS) and disease-free survival (DFS), was then analyzed.

RESULTS: Of the 83 EC tissues, 16 (19.28%) had low TAMs density and low microvessels density (MVD), 5 (6.02%) had high TAMs density and low MVD, 40 (48.19%) had low TAMs density and high MVD, and 22 (26.51%) had high TAMs density and high MVD. There was a statistically significant difference in MVD between different TAMs density subgroups (p = 0.002). High MVD risk with high TAMs density is significantly increased (OR = 0.421 [95% CI: 0.219-0.784], p = 0.011). A statistically significant difference in DFS was found between high and low TAMs density subgroups (p < 0.05), but no difference between high and low MVD subgroups (p > 0.05). Multivariate analysis by Cox regression indicated that both the TAMs density and MVD were the independent prognostic factors.

CONCLUSIONS: The TAMs density and MVD of tumor microenvironment in surgical specimens were strong prognosticators for EC patients. High TAMs and high MVD were associated with shorter DFS and shorter OS, respectively.