|
Back to 2014 Annual Meeting Posters
Intraoperative Portable Gammacamera for Sentinel Node Mapping in Colon Cancer
Rocio Anula*1, Julio Mayol1, Patricia Fierro2, Roberto Delgado-Bolton2, María JesúS Peña1, Jaime Otero De Pablos1, José Luis Carreras2, Jesus Alvarez1
1Surgery, Hospital Clínico San Carlos, Madrid, Spain; 2Nuclear Medicine, Hospital Clínico San Carlos, Madrid, Spain
BACKGROUND
Sentinel lymph node (SLN) biopsy has been proposed for ultrastaging in patients with stage II colon cancer. However the optimal technique for SNL detection in the colon has not been established. The purpose of this study was to evaluate the safety and feasibility of in vivo SLN mapping in colon cancer patients using an intraoperative portable gammacamera, and to determine if upstaging occurrs.
PATIENTS AND METHODS
Between Feb 2007 and Oct 2012, consecutive patients who underwent elective curative surgery for histologically confirmed non-disseminated colon cancer were included this study. Those patients with metastatic disease and/or with tumors invading adjacent organs were excluded. Intraoperatively, 0.5 mCi of 99Tc - radiocolloid was subserosally injected in the four cardinal points around the tumor. In vivo lymphatic navigation was accomplished with dynamic intraoperative lymphoscintigraphy using a portable gammacamera (Sentinella, OncoVision, Spain) and assisted by a gamma probe. SLN was defined as the first identified node with the highest gamma emission. The ex vivo technique was used in those cases in which no in vivo migration occurred. All lymph nodes were analysed by conventional haematoxylin-eosin (HE) staining, and negative SLNs underwent in depth analysis using immunohistochemical (IHC) staining. Patients with positive lymph nodes were offered adjuvant chemotherapy, and all of them were routinely monitored at 1, 6, and 12 month-intervals.
RESULTS
A total of 55 patients were included in the study, 31 were men and 24 women. The average age was 73.6 years (range: 38.6- 89.9). The success rate of SLN identification was 74.5% (41/55), with 20% of them with more than one SNL. Histological analysis identified 20% of positive SLNs (11/41). SLN identification rate decreased with increasing T (p=0.010), as well as positive SLNs with increasing N (p<0,001). False negative rate was 26.6%. (8/30). The average follow-up time was 17.5 months (IQR: 3.47- 35.16), with 16,4% (9/55) of recurrence. Overall disease-free-survival at 48 months was 67.7%, 47.6% in patients with positive SLNs, and 83.5% in patients with negative SLNs.
CONCLUSIONS
SLN detection using a portable gammacamera intraoperatively is a feasible procedure for colorectal cancer. Tumor size directly correlates with SLN identification failure and higher false negative rates. This might be explained by direct tumoral invasion of lymphatic vessels.
Back to 2014 Annual Meeting Posters
|
