Microvascular structure and perfusion imaging of colon cancer by means of contrast-enhanced ultrasonography

Objective: To determine whether contrast-enhanced ultrasonography (CEUS) can be used to discriminate between colon cancer and acute inflammation, and between mucinous and non-mucinous carcinoma. Materials and methods: CEUS (with perflubutane microbubbles) was performed in two study groups: colon cancer (n = 34) and acute inflammation (n = 14). For evaluation, the microvascular structure was classified as irregular or regular, and vessel diameter was classified as ≥2 mm or < 2 mm. Tumor enhancement was classified as homogeneous, heterogeneous (obvious defect), or hypoenhancement. Moreover, the defect area was classified according to the presence or absence of vessels. Differences in imaging features between the two groups or between types of tumors were examined statistically. Results: The vascular structure was irregular in 76.5% of colon cancers but only 28.6% of acute inflammations (P < 0.01). A significantly greater number of cancers contained vessels ≥2 mm (70.6% vs. 7.1%) (P < 0.001). Both abnormalities were found in 58.8% of colon cancers but in none of the acute inflammations. Enhancement patterns differed between tumor types, with mucin pools being readily identifiable. Conclusion: Differentiation between colon cancer and acute inflammation is possible with CEUS. Furthermore, prediction of mucinous vs. non-mucinous adenocarcinoma is possible.