Tumor growth was monitored with weekly caliper measurements, as well as weekly MR scans using a GE 1.5 T Signa MR scanner (GE Healthcare, Waukesha, WI) and a 3-in diameter surface coil, on which 1–2 mice were imaged per scan. MR images were acquired using the FSE T2-weighted sequence (TR/TE = 2200/85 ms), resulting in a resolution of 0.243 × 0.243 × 1.2 mm3 per voxel and a field of view of 7 × 7 cm2 for axial scans.
Tumor volume was measured with the calipers by measuring two perpendicular lengths of the tumor and using a formula found elsewhere in the literature (Takahashi et al 2013 (link)):
where d is the shorter diameter and D is the larger diameter. Tumor volume was measured from the MR scans by contouring each slice of the axial scans on a program developed within our institution. Tumors were contoured used Canny edge detection to define tumor boundaries. Tumor growth for each tumor was quantified as the ratio of tumor volume one and two weeks after treatment to that immediately before treatment:
Tumor volume was measured with the calipers by measuring two perpendicular lengths of the tumor and using a formula found elsewhere in the literature (Takahashi et al 2013 (link)):
where d is the shorter diameter and D is the larger diameter. Tumor volume was measured from the MR scans by contouring each slice of the axial scans on a program developed within our institution. Tumors were contoured used Canny edge detection to define tumor boundaries. Tumor growth for each tumor was quantified as the ratio of tumor volume one and two weeks after treatment to that immediately before treatment:
