Giuseppe Spinoglio, MD1, Dario Ribero1, Fabio Priora2, Wanda Petz1. 1European Institute of Oncology, 2Santi Antonio e Biagio e Cesare Arrigo Hospital Alessandria Italy
Background: Although type and extent of lymphadenectomy in colorectal cancer surgery are well established, potential aberrant lymphatic drainage in rectal cancer and risk of missed identification of lymph node (LN) metastases, particularly micrometastases, in initial colon tumours represent unsolved challenges. Accurate methods of LN mapping are therefore of pivotal importance.
Aims: To evaluate efficacy of indocyanine green (ICG) peritumoral injection and intraoperative fluorescence assessment in detecting the pattern of lymphatic drainage (i.e. sentinel LN and aberrant drainage).
Methods: In colon cancer patients, 1-3 mg of ICG were injected in the subserosal area around primary tumour during surgery, while in rectal cancer patients 5 mg of ICG were injected endoscopically in the submucosa 24-48 hours before the operation.
Surgical resection was realized robotically; standard lymphadenectomy was performed in all patients. In the presence of aberrant lymphatic drainage, stained LN were retrieved.
Immunohistochemistry was performed on stained LN with the aim of detecting micrometastases.
Results: 40 patients with colon cancer and 21 patients with rectal cancer were included in the study.
Detection rate of colon sentinel LN was 92.8 % (37/40 patients); in 18 patients (48%) more than one LN were identified, none outside of standard lymphatic basin.
In all, 54 LN were analyzed, with an incidence of micrometastases of 11.1% (6/54).
In rectal cancer patients, detection rate was 80.9 % (17/21 patients); in 8 patients (47%) multiple LN were identified (in all 25 LN were detected).
While no micrometastases were found, 13/25 identified LN (52%) were outside of the standard lympadenectomy area (8 para aortic, 5 lateral pelvic LN).
No adverse effects were observed.
Conclusions: ICG injection and intraoperative fluorescence is a reliable method for detection of sentinel LN and lymphatic drainage in colorectal cancer. Although more data are needed, our results suggest that this technique might have a significative impact on the surgical approach to colon and rectal cancers.
Presented at the SAGES 2017 Annual Meeting in Houston, TX.
Abstract ID: 84454
Program Number: ETP756
Presentation Session: Emerging Technology Poster
Presentation Type: Poster