Cancer metastasis to the bone can dysregulate normal bone remodeling process. Cancer cells can directly and indirectly send signals to the osteoclasts and vice versa. This can result in abnormal increase in osteoclast differentiation and activity, leading to heightened bone resorption, called osteoclastic osteolysis. There are medications for osteoclastic osteolysis, named bisphosphonate and denosumab(anti-RANKL), which reduces the abnormal osteoclast activity. However, observations have shown that cancer-induced osteolysis can still exist, suggesting that there are other agents in the bone responsible for the continued osteolysis. Studies in the last two decades have shown that osteocyte can remodel its perilacunar microenvironment during physiological and pathological processes. Based on these studies, it can be hypothesized that with spread of cancer cells to bone, osteocyte may be an agent partly causing osteolysis through remodeling its peripheral microenvironment, which is referred to as osteocytic osteolysis.

The objective of this research is to investigate the validity of the above hypothesis. For this purpose, herein, the effects of breast cancer cells metastasis on lacunar geometry are examined. The main parameters of interest are lacunar volume, aspect ratio, and surface area. The values of these parameters are determined by applying image processing techniques to the high-resolution micro-CT scans obtained from healthy and cancer-bearing mice tibiae