A technology capable of imaging tissue, at or near the cellular level, could lead to the detection of neoplasias at earlier stages than currently possible. This could significantly improve patient outcomes, since once cancer becomes metastatic, cure is difficult. Optical coherence tomography (OCT), a recently developed imaging technology, has ben shown to achieve resolution in the cellular and subcellular range, and it could improve the diagnostic range of clinical imaging procedures. To assess the clinical applicability of OCT, neoplastic specimens from the urinary, gastrointestinal and female reproductive tract were imaged. Sharp differentiation of structures included the mucosa/submucosal/muscularis boundaries, epithelium, glands, supportive tissue, and intramural cysts. The ability of optical coherence tomography to image tissue microstructure at or near the cellular level make it a potentially powerful technology for minimally invasive assessment of tissue microstructure. The resolution of optical coherence tomography, which is greater than any current clinical imaging modality, make it particularly attractive for the assessment of early neoplastic changes.