Nynke S. van den Berg MSc, Abstract Co-Author: Nothing to Disclose

Oscar Brouwer, Abstract Co-Author: Nothing to Disclose

Bob Schaafsma, Abstract Co-Author: Nothing to Disclose

Martin Klop, Abstract Co-Author: Nothing to Disclose

Alfons Balm, Abstract Co-Author: Nothing to Disclose

Fijs van Leeuwen, Presenter: Nothing to Disclose

Michiel W. Van Den Brekel MD, PhD, Abstract Co-Author: Nothing to Disclose

Alexander Vahrmeijer, Abstract Co-Author: Nothing to Disclose

Omgo Nieweg, Abstract Co-Author: Nothing to Disclose

Renato Valdes Olmos, Abstract Co-Author: Nothing to Disclose

In head and neck melanoma and oral cavity cancers, sentinel lymph node (SLN) mapping is generally performed by injection radio-colloid surrounding the primary tumor followed by lymphoscintigraphy. Intra-operatievely, SLNs can then be localized using a handheld gamma ray detection probe combined with patent blue dye for visual detection. In this study we assed the added value of intra-operative fluorescence imaging to the conventional radio guided procedure using ICG-99mTc-nanocolloid, a hybrid tracer that is both radioactive and fluorescent.

Fourty-eight patients were peritumorally injected with ICG-99mTc-nanocolloid. SLNs were pre-operatively defined using lymphoscintigraphy and SPECT/CT. Prior to surgery, patent blue dye was injected in 16 melanoma patients. Intra-operatively, SLNs were detected with a handheld gamma ray detection probe and a handheld near-infrared fluorescence camera. To confirm complete removal of all SLNs, pre-incision and post-excision imaging with a portable gamma camera was performed.

Preoperatively, a total of 118 SLNs were identified on the lymphoscintigraphy and SPECT/CT images. In-tra-operatively, 91% of the SLNs could be localized using both the gamma ray detection probe and the fluorescence camera. The remaining SLNs (9%) were located close to the injection site and were solely detected using the fluorescence camera. In patients in whom blue dye was used, 49% of SLNs stained blue. With the portable gamma camera 8 additional SLNs could be identified. Ex vivo all radioactive lymph nodes were fluorescent and vice versa, underlining the value of the tracer during the procedures. Pathological SLN analysis revealed a SLN metastases in 5 patients.

With the use ICG-99mTc-nanocolloid both pre-operative SLN mapping and intra-operative radio- and fluorescence guidance towards the SLNs in head and neck cancer patients were feasible. The addition of fluorescence imaging was found to be of particular value when SLNs were located in close proximity to the primary injection site, and in cases where vital blue dye is of limited value.

The addition of fluorescence imaging to the conventional radio guided procedure may improve SLN detection which can lead to more accurate staging and less invasive surgical procedures.

van den Berg, N, Brouwer, O, Schaafsma, B, Klop, M, Balm, A, van Leeuwen, F, Van Den Brekel, M, Vahrmeijer, A, Nieweg, O, Valdes Olmos, R, Hybrid Radio and Fluorescence-guided Sentinel Lymph Node Biopsy in Head and Neck Malignancies.  Radiological Society of North America 2012 Scientific Assembly and Annual Meeting, November 25 - November 30, 2012 ,Chicago IL. http://archive.rsna.org/2012/12028771.html