Carbon Black Tattoo in Colon Cancer

The study is designed to elucidate whether carbon black suspension endoscopic tattoo enhances visibility of lymph nodes or tumor tissue on dissection of colonic surgical specimen, thereby making improvement in staging defined as better pTNM stage via better visualisation of carbon marked metastatic or sentinel lymph nodes or marked primary tumor or adjacent tissues.

Other objectives are: to assess intraoperative visibility of carbon black tattoo in the tumor region and surrounding tissues to assess microscopic distribution of carbon ink in the layers of the colonic wall and adjacent tissues to assess complications related to carbon black tattoo procedure like microscopic fibrosis, micro- or macroscopic scarring, inflammatory reactions to assess long-term effects of ink injections on control endoscopies at 6 and 12 months to assess dissection time in tattooed-non tattooed lymphatic tissues

Examine the SPOT syringe to verify that the pigment is fully suspended. A 23 or 25 G sclerotherapy needle is recommended for this procedure, attach the syringe and prime with SPOT. After injection catheter is primed, manoeuver with the endoscope for optimal injection position and inject tangentially, at a 30-40˚ angle to the mucosa and create a saline bleb to find the submucosal plane prior to injecting SPOT to reduce risk of intramural injection. Document both the depth of scope and anatomic location of each tattoo and the ink consumption as well. Place injection 2-3 cm distal (downstream) of the area of interest. Use 0.5-0.75 mL per injection site and no more than 8 mL per patient. Place SPOT tattoos in 3-4 quadrants around the lumen to increase likelihood of visualisation.

Number of tumors visualised from peritoneal cavity/number of tattoos visualised form peritoneal cavity

Distance in cm from tumor wich far carbon injection marked mucosa and adjacent tissues Number of inflammatory cells per field of view in injection site vs. non-injected mucosa Number of dissected total/normal/metastatic/carbon colored lymph nodes

Inclusion Criteria: Male or female aged 18 years or above undergoing colonoscopy for suspected colonic malignancy Participant is able to give informed consent for participation in the study Patient is presumably selected for surgery within 30 days following tattoo injection Exclusion Criteria: Patients under the age of 18 Patients unable to give informed consent or ineligible for surgery Tumor in the coecum dome or in the rectum (<15 cm) Known allergy to suspension ingredients

Askin MP, Waye JD, Fiedler L, Harpaz N. Tattoo of colonic neoplasms in 113 patients with a new sterile carbon compound. Gastrointest Endosc. 2002 Sep;56(3):339-42. doi: 10.1016/s0016-5107(02)70035-7.