Prostate cancer microvessels: A novel method for three-dimensional reconstruction and analysis

BACKGROUND. Studies of prostate cancer microvessels to date have relied on routine two-dimensional images from histologic tissue sections, and there have been no previous reports of three-dimensional (3D) reconstruction and analysis of prostatic microvessels in benign or malignant specimens. Knowledge about the 3D architecture of microvessels would be useful for determining the utility and limitations of two-dimensional (2D) measures, as well as for determining the usefulness of 3D measures to predict pathologic stage and patient outcome in prostate cancer. However, the ability to study microvessels in 3D must first be demonstrated. METHODS. We developed a novel method to visualize and analyze prostate microvessels in three dimensions from serially-sectioned prostate specimens, including tissue preparation, reconstruction of serial histologic sections into 3D volumes, extraction of vessels from this data set, and calculation of geometric characteristics. Eleven regions of benign and cancer tissue were studied and compared in an effort to validate our methodology. RESULTS. Microvessels and glandular elements from benign and malignant tissue were visualized together in three dimensions. In the 3D visualizations, microvessels associated with cancer were seen to have more arbitrary pathways, increased tortuosity, and a more casual relationship with glandular elements than microvessels associated with benign tissue. A quantitative measure, the volume length density, discriminated between benign tissue and cancer better than simple microvessel density in this exploratory study. CONCLUSIONS. Microvessels in prostate cancer have a more homogeneous distribution and greater tortuosity than those in benign tissue. Volume length density of microvessels shows promise as a 3D marker in prostate cancer.