Tattoo of colonic neoplasms in 113 patients with a new sterile carbon compound

BACKGROUND: Endoscopic marking of intestinal lesions is essential when difficulty is anticipated with subsequent localization during surgical resection or postpolypectomy surveillance. The most commonly used indelible marker has been India ink, which must be diluted and sterilized, a cumbersome process. SPOT, a prepackaged, sterile Food and Drug Administration-approved formulation of pure carbon particles in suspension, eliminates the need for preinjection preparation. METHODS: Ten patients with colonic polyps deemed endoscopically unresectable or malignant-appearing had the area surrounding the lesions injected with SPOT and subsequently underwent surgical resection. An additional 103 patients underwent colonoscopic injection with SPOT and were followed endoscopically or underwent surgery at another hospital. RESULTS: The SPOT injection sites were visible to the surgeons in all 10 cases. On histopathologic evaluation, none of the resection specimens exhibited necrosis or abscess formation. In total, there were 118 SPOT injections in 113 patients; none had fever, abdominal pain, or any other signs or symptoms of inflammation develop. In the nonoperated group, 42 patients subsequently underwent colonoscopies at our institution, and in all cases stains were readily identifiable at the injection sites. CONCLUSIONS: SPOT is a safe and effective marker for use at colonoscopy when surgical resection is anticipated. It is also useful for endoscopic follow-up of patients who have not undergone surgery.