New microscope peers inside living tumors to see how they behave

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Age ≥ 18 years of age * Eastern Cooperative Oncology Group (ECOG)Performance Status of ≤ 2 * Measurable tumor by direct visualization requiring surgical resection in the operating room (OR) * Tumor types of origin include gastric, pancreatic, hepatobiliary, colorectal, sarcoma, brain, or breast cancer that may involve the axillary lymph nodes cancers. Tumors may be primary or metastatic * Subject must understand the investigational nature of this study and sign an Independent Ethics Committee/Institutional Review Board approved written informed consent * Subject must have a skin prick test pre-operatively (at the time of the preoperative visit and after signed informed consent for entry into this clinical trial is given) to determine any sensitivity to fluorescein Exclusion Criteria: * Uncontrolled intercurrent illness including, but not limited to, ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social situations * Renal dysfunction as defined as a glomerular filtration rate (GFR) \< 45 * Liver dysfunction as defined by Child-Pugh score \> 5, or liver function test (LFT)'s 1.5 x above normal range * Any known allergy or prior reaction to fluorescein or a positive skin prick test to fluorescein * Pregnant or nursing female subjects, determined preoperatively with a urine pregnancy test * Unwilling or unable to follow protocol requirements * Any condition which in the investigators' opinion deems the patient unsuitable (e.g., abnormal electrocardiography \[EKG\], including T wave inversion, elevated T waves, prolonged QRS interval, or conduction blocks) or that requires further work-up (including cardiac echo or stress test) * Any condition that excludes surgical resection as the standard of care for the patient