Much prostate cancer research is based on cell culture results. Recent genomic studies found major differences between primary prostate cancer tissue and established prostate cancer cell lines, which calls into question the clinical relevance of study results based on cell cultures.Using primary cultures of prostate cancer cells from prostatectomy specimens seems to be a reasonable solution, but primary cell cultures are much more difficult to establish. In this study, a primary cell culture model was combined with an invasion assay. With this combination it was possible not only to select invasive cell clones from the primary culture but also to culture these cells in a three-dimensional model, forming spheroids. A further characterization of this cell population was done by comparative genomic hybridization, showing numerous genetic alterations. The presented cell culture model offers, for the first time, an opportunity to isolate invasive growing cells from primary prostate cancer tissue and cultivate these cells for further analyses.