In this EAGER project a new engineering design for an endoscopic medical device is proposed. This new approach will allow a working channel to be included within an ultrathin and flexible endoscope of 1.7-mm diameter. Instead of shrinking the conventional endoscope of separate channels for illumination, imaging, flushing, and biopsy; the new approach will place an ultrasmall imager at the tip of a working channel that provides flushing and biopsy. This new approach is transformative for clinical imaging and critically helpful for accelerating the development of optical biopsy. The working channel will provide the key requirements of fluid exchange and tissue vacuum, biopsy, and retrieval. Testing will involve the biopsy apparatus, which is suction of the epithelial mucosa into a cutting chamber that is connected to the proximal end for biopsy retrieval. The biopsy apparatus will be modified in an iterative manner using test results from a synthetic phantom and ex vivo pig lung. The integrated microendoscope and biopsy apparatus will be fabricated and tested for endoscopic guidance to specific sites for biopsy. Fluorescently labeled cells and microspheres will be injected into the luminal wall so that accuracy as well as adequacy of the biopsy will be the quantitative milestones.