We investigated the effect of
ibandronate on three-dimensional (3-D) microstructure and bone mass in experimentally induced
tumor osteolysis. Walker
carcinosarcoma cells were implanted into the left femur of female rats that received 26-day
ibandronate pretreatment followed by continued
therapy or
ibandronate posttreatment only. A
tumor-only group received isotonic saline. At endpoint, excised femurs were scanned using microcomputed tomography (microCT) to assess bone volume density, bone mineral content, trabecular number/thickness, and separation for cortical plus trabecular bone or trabecular bone alone. Compared with the nonimplanted right femur, bone volume and surface density and trabecular number and thickness were reduced in the distal left femur following
tumor cell implantation. microCT analysis revealed greater cortical and trabecular bone
mineral content in the preventative and interventional (pre-post
tumor)
ibandronate group, and the interventional (post-
tumor)
ibandronate group, versus the
tumor-only group. Bone volume density was significantly higher in pre-post and post-
tumor groups compared to the
tumor-only group. After preventative and interventional
ibandronate, bone volume density and trabecular thickness were 13% and 60% greater, respectively, than in the post-
tumor treatment group. 3-D microCT images confirmed microstructural changes. We conclude that combined interventional and preventative
ibandronate preserves bone strength and integrity more than intervention alone.