Sentinel lymphonodectomy in early vaginal cancer using combined near infrared fluorescence from indocyanine green and technetium-99m nanocolloid – a first case report

Nowadays, sentinel diagnostic is been made with technetium-99m-(Tc-99m)-nanocolloide as a radioactive marker and sometimes patent blue. In the last years, indocyanin green has been evaluated for sentinel diagnostic in different tumor entities. Indocyane greene is a fluorescent molecule which emits a light signal in the near infrared band after excitation. Our study aims to evaluate indocyanin green compared to the gold standard Tc-99m-nanocolloid. We report over a patient with an unifocal vaginal cancer. Sentinel diagnostic was carried out using Tc-99m-nanocolloid, indocyanin green and patent blue. After SPECT/CT, we examined each groin for light signals from the near infrared band, for radioactivity and for blue staining. A sentinel lymph node was defined as a Tc99m-nanocolloide positive lymph node. All sentinel lymph nodes and all additional blue or fluorescent lymph nodes were excised and tested; then sent to histologic examination. The procedure could be accomplished without problems. We found four sentinel lymph nodes with indocyanin green fluorescence, which were positive for radioactivity from Tc-99m and therefore defined as sentinel lymph nodes. Two further lymph nodes, which showed positivity for indocyanin green signals, but not for Tc-99m were found in the left groin. The final tumor stage was pT1b, pN0 (0/6, 0/4 SLN). We saw no adverse events or complications in this patient. Our case report shows that near infrared fluorescence deriving from ICG is a promising approach for sentinel identification in vaginal cancer. If studies using sentinel lymphonodectomy will be planned, a combined approach using Tc-99m-nanocolloide and indocyanin green could be useful. Correspondence to: Philipp Soergel, MD, MHBA, Department of Obstetrics and Gynecology, Hannover Medical School, Carl-Neuberg-Strasse 1, 30625 Hannover, Germany; Tel: 0049 511 532 6144; Fax: 0049 511 532 6145; E-mail: [email protected]