Visual probing of rectal neoplasia: near-infrared interrogation of primary tumors and secondary lymph nodes.

Laparoscopic and endoscopic colorectal intervention and operations have their basis in real-time, image-based decision-making and step-by-step sequenced technical progress. The capacity to visualize accurately malignant disease wherever it may be including within the primary lesion and its draining lymph node basin as well as at potential sites of metastatic harbor (i.e. peritoneum, liver and lung) would allow more accurate surgery at the time of operation and enable personalized, stratified surgical intervention. In addition, such capacity could efficiently compress the diagnostic and therapeutic stages of a patient's progress from presentation, through work-up and onto appropriate treatment, important in this era of restricted resource and increased user demand. Near-infrared endolaparoscopic illumination enables broad spectral imaging of tissue in situ, most often, at present, in conjunction with the approved safe and low-cost fluorophore indocyanine green. While additional targeted agents are in development, here we detail how this developed and available technology may be used as a visual probe of neoplasia to inform surgeons regarding functional, tissue characterization through the direct observation of metabolic and metabolomic processes within the area under inspection perhaps helping in the distinction between invasive cancer and non-invasive dysplastic lesions. This understanding can inform and accelerate development of specific agents and techniques that can better advance surgical practice into the era of surgical data science and true precision surgery.