Abstract: Disclosed is a three-dimensional (3-D) in vitro model for studying and subsequently treating cancer dormancy. The model is specifically useful in studying breast cancer and may be used for drug discovery because it maintains the breast cancer cells in a dormant state, unlike conventional two-dimensional (2-D) tissue culture plastic (TCP). Tumor-forming breast cancers cells were seeded on the 3-D model scaffolds and remained viable without proliferation. They also express stem cell markers typical for dormant cells. Dormant breast cancer cells also maintain their phenotype when seeded on the 3-D model unlike conventional 2-D models. The 3-D model includes a fibrous polycaprolactone with 30 wt. % hydroxyapatite. The 3-D model mimics the structure of bone tissue.