Necrosis degree displayed in computed tomography images correlated with hypoxia and angiogenesis in breast cancer

The objective of this study was to investigate the correlation between the degree of necrosis displayed in computed tomography (CT) image and the expression of hypoxic and angiogenesis biomarkers of breast cancer.

Forty-four breast cancer cases were examined with CT before surgery. Tumor specimen expressions of glucose transporter 1 (Glut1), hypoxia-inducible factor 1α (HIF-1α), carbonic anhydrase IX (CA IX), vascular endothelial growth factor (VEGF), and CD34 (as a marker of vascular endothelial cells) were detected by immunohistochemistry.

The expressions of Glut1 and CA IX were localized primarily to the edges of necrotic areas or intraduct surface; there was a strong correlation between HIF-1α-positive expression and CA IX-positive expression (P < 0.001), and higher Glut1 or CA IX expression grade was associated with lower microvessel density (MVD) value. In CT enhanced images, lower relative CT (rCT) values were associated with more significant necrosis in the tumor; rCT value correlated positively with MVD significantly (r = 0.319, P = 0.035), and higher Glut1 or CA IX expression grade correlated with lower rCT values (P = 0.001 and 0.003, respectively). Although high VEGF expression was significantly correlated with high HIF-1α expression (P < 0.001), there were no correlations between VEGF and MVD, and HIF-1α and MVD (P = 0.559 and 0.710, respectively), and the difference of the mean rCT value between high VEGF or HIF-1α expression group and low VEGF or HIF-1α expression group was not significant.

In breast cancer tissues, Glut1 and CA IX are key hypoxia biomarkers. Importantly, detection of necrosis in breast cancer tissue via CT enhanced imaging may prognosticate hypoxia and angiogenesis status and help to determine treatment plan of advanced breast cancer.