Feasibility Study to Develop Sentinel Lymph Node Mapping in Rectal Cancer Patients

Novel Sentinel Lymph Node Mapping Technique in Early Stage Rectal Cancer

The purpose of this study is to see if investigators can develop a technique to identify sentinel lymph nodes in the rectum for rectal cancer patients with the use of a radiotracer (Tc-sulfur colloid), a dye (Spot), and imaging, both pre- and intraoperatively. Eligible patients are those with stage I-III rectal cancer undergoing standard low anterior resection or abdominoperineal resection.

Investigators hypothesize that use of a unique intraoperative lymphatic mapping technique using a mobile gamma camera will identify the sentinel lymph node in patients with rectal cancer with greater than 80% sensitivity.

Subjects will receive injections of the tracer and dye prior to surgery, have preoperative SPECT/CT imaging to be used as a guide to the rectal lymphatic system and then proceed to their scheduled surgery. During surgery, images of the rectum will be taken with a unique mobile gamma camera prior to removal and upon resection.

If surgeons are able to identify the sentinel lymph nodes surrounding the rectal tumor, the hope is to combine this technique with a less invasive surgery called transanal endoscopic microsurgery (TEM) for early stage rectal cancer patients.

Inclusion Criteria:

• Adult patients with stage I,II, or III rectal cancer undergoing standard trans- abdominal low anterior resection or abdominoperineal resection surgery at the University of Virginia
• Willing and able to give written informed consent

Exclusion Criteria:

• Patients less than 18 years of age
• Women who are pregnant and/or breastfeeding
• Prisoners
• Unable to give written informed consent
• Participants with medical contradictions or have potential problems complying with the requirements of the protocol, in the opinion of the investigator