We used vernier calipers to measure B16F10 induced solid melanoma tumors; where measuring the volume of tumor was easy (L*W*H). However, we now are geared to induce Braf/Pten mediated tumors and unlike B16F10, these tumors have inconsistent vertical growth. Also, at times we observe lot of small tumors induced post tamoxifen and they don't coalesce posing problems in radial and vertical growth measurements. Your suggestions are much appreciated.