Radioguided localization of occult colonic lesions during open or laparoscopic surgery: an update

The applications of radioguided surgery, an approach to oncologic surgery involving a multidisciplinary team, are expanding at a rapid pace. The technique of radioguided occult lesion localization (ROLL) was originally introduced in the mid- 90s for applications in breast surgery, and later adapted also to other tumor lesions such as solitary pulmonary nodules (during either open or laparoscopic surgery) and colonic lesions. Concerning the latter, in particular, the technique called radioguided occult colonic lesion identification (ROCLI) consists of identifying, with the aid of intraoperative gammaprobe counts, small lesions that may escape colic intraoperative palpation, after prior tagging of the lesions performed endoscopically through peri- or intra-lesional injection of Technetium-99m-labeled human albumin macroaggregates (99mTc- MAA), a particulate radiopharmaceutical (25-100 μm) that does not migrate from the site of interstitial administration. Since September 2001, ROCLI has been employed in 12 patients, using a collimated gamma- probe measuring 11 mm in external diameter (Scintiprobe MR100 Pol.Hi.Tech.). All patients underwent preoperative colonoscopy in order to inject 0.2 mL of a 99mTc-MAA suspension (10-20 MBq) into the submucosa or intra-perilesionally; such tagging required only a few minutes. Eight of the 12 patients were then submitted to open laparotomy, while laparoscopic access was utilized in the remaining 4 patients. In all 12 patients, localization of the lesion with the ROCLI technique was technically feasible, safe, efficient and highly accurate, enabling quick detection of the lesion during surgery, with a 100% success rate. No complications occurred, and there was no risk of contamination by ionizing radiation.