PMC

Box whisker plot of microvascular density evaluating region of interest drawn on hotspots.
Distribution of low and high groups is shown in K^trans (A) and K_ep (B).

Representative scatter diagrams showing relationships between microvascular density, necrotic fraction, and dynamic contrast enhanced MRI derived parameters from hotspots.
A, B. K^trans and microvascular density (Spearman's correlation = -0.61, p = 0.06) (A), K_ep and microvascular density (Spearman's correlation = -0.60, p = 0.07) (B). Dashed line indicates 95% confidence interval. C. Necrotic fraction and K^trans (Spearman's correlation = -0.34, p = 0.31). Solid circle represents group that shows low necrotic fraction and high K^trans. Dashed circle represents group who showed high necrotic fraction and low K^trans. MVD = microvascular density, NF = necrotic fraction

Pixel by pixel analysis of K^trans in tumor of another representative mouse (#10).
A. K^trans values of whole tumors and hotspots were 0.113/sec and 0.237/sec respectively. ROI 1 and ROI 2 are marked by red and green solid lines, respectively. B. Hematoxylin and Eosin staining of corresponding section of mouse #10. Large amount of necrosis is shown (original magnification, × 2). C. Hematoxylin and Eosin staining including hotspot region. Tumor necrotic fraction is 0.31 (original magnification, × 40). Yellow line indicates tumor border and red line indicates area of necrosis. D. CD 31 staining of tissue from mouse #10. Microvascular density count is 108 (original magnification, × 200).

Pixel-by-pixel analysis of K^trans in tumor of representative mouse #2 evaluated by dynamic contrast enhanced MRI with Tofts model.
A. K^trans values of whole tumor (ROI 1) and hotspot (ROI 2) are 0.285/sec and 0.429/sec, respectively. ROI 1 and ROI 2 are marked by red and green solid lines. B. Hematoxylin and Eosin staining of corresponding section of mouse #2 (original magnification, × 2). Necrosis is noted in center of tumor. C. Hematoxylin and Eosin staining includes hotspot area. Tumor necrosis fraction is 0.03 (original magnification, × 40). Yellow line indicates tumor border and red line indicates area of necrosis. D. CD 31 staining of tumor from mouse #2. Microvascular density count is 53 (original magnification, × 200).