PURPOSE

To explore the relationship between tumor-associated macrophages (TAMs) in gastric cancer and dual-energy computed tomography (DECT) parameters.

METHODS

This retrospective study was conducted with patients who underwent both DECT examination and gastric cancer resection. 89 patients (mean age ± standard deviations, 64.36 ± 9.37) were finally enrolled and analyzed. DECT parameters included iodine concentration (IC), normalized IC (NIC), effective atomic number (Z), the slope of the Hounsfield unit curve (λ), and CT value in the late arterial phase (LAP) and venous phase (VP). CD206+ TAM infiltration density was detected by immunohistochemistry. The relationships between DECT parameters and TAM were analyzed with the Spearman rank correlation test. DECT parameters in different TAM infiltration density groups were compared with the Mann-Whitney U test.

RESULTS

CD206+ TAM infiltration density demonstrated statistically significant weak correlations with several DECT parameters in LAP (r = 0.236-0.258, all P < 0.05) rather than in VP in all 89 patients. In 48 tubular adenocarcinoma (TAC) patients, correlations in LAP were weak-to-moderate and involved more parameters (r = 0.287-0.358, all P < 0.05), while no significant correlations existed in poorly cohesive carcinoma (PCC). Z, and λ significantly differed between low and high CD206+ TAM infiltration groups in TAC (P < 0.05), rather than in PCC.

CONCLUSION

DECT parameters in LAP showed weak to moderate correlations with TAM infiltration density in gastric adenocarcinoma. These correlations were statistically significant in TAC but absent in PCC. DECT has the potential to assess TAM infiltration density in an exploratory and adjuvant manner, though its assessment efficacy is affected by different WHO subtypes and heterogeneity of gastric cancer.