Detection of the sentinel lymph node with hybrid tracer (ICG-[99mTc]Tc-albumin nanocolloid) in intermediate- and high-risk endometrial cancer: a feasibility study

Nuria Sánchez-Izquierdo; Sergi Vidal-Sicart; Francisco Campos; Aureli Torné; Martina Aida Angeles; Federico Migliorelli; Meritxell Munmany; Adela Saco; Berta Diaz-Feijoo; Ariel Glickman; Jaume Ordi; Andrés Perissinotti; Marta Del Pino; Pilar Paredes

doi:10.1186/s13550-021-00863-x

Detection of the sentinel lymph node with hybrid tracer (ICG-[^99mTc]Tc-albumin nanocolloid) in intermediate- and high-risk endometrial cancer: a feasibility study

EJNMMI Res. 2021 Dec 14;11(1):123. doi: 10.1186/s13550-021-00863-x.

Authors

Nuria Sánchez-Izquierdo¹, Sergi Vidal-Sicart^{1

2}, Francisco Campos¹, Aureli Torné^{3

2

4}, Martina Aida Angeles^{3

5}, Federico Migliorelli⁶, Meritxell Munmany³, Adela Saco^{7

2

4}, Berta Diaz-Feijoo^{3

2

4}, Ariel Glickman³, Jaume Ordi^{7

4

8}, Andrés Perissinotti¹, Marta Del Pino^{3

2

4}, Pilar Paredes^{9

10

11}

Affiliations

¹ Department of Nuclear Medicine, Hospital Clínic of Barcelona, Villarroel 170, 08036, Barcelona, Spain.
² Institut d'Investigacions Biomèdiques August Pi I Sunyer (IDIBAPS), Barcelona, Spain.
³ Institute Clinic of Gynecology, Obstetrics, and Neonatology, Hospital Clínic of Barcelona, Barcelona, Spain.
⁴ Faculty of Medicine, University of Barcelona, Barcelona, Spain.
⁵ Department of Surgical Oncology, Institut Claudius Regaud, Institut Universitaire du Cancer de Toulouse - Oncopole, Toulouse, France.
⁶ Department of Gynecology and Obstetrics, Centre Hospitalier Intercommunal des Vallées de l'Ariège, Saint-Jean-de-Verges, France.
⁷ Department of Pathology, Hospital Clínic of Barcelona, Barcelona, Spain.
⁸ ISGlobal, Barcelona Institute for Global Health, Hospital Clínic-Universitat de Barcelona, 08036, Barcelona, Spain.
⁹ Department of Nuclear Medicine, Hospital Clínic of Barcelona, Villarroel 170, 08036, Barcelona, Spain. pparedes@clinic.cat.
¹⁰ Institut d'Investigacions Biomèdiques August Pi I Sunyer (IDIBAPS), Barcelona, Spain. pparedes@clinic.cat.
¹¹ Faculty of Medicine, University of Barcelona, Barcelona, Spain. pparedes@clinic.cat.

Abstract

Purpose: Indocyanine green (ICG) is frequently used for the detection of the sentinel lymph node (SLN) in gynecology, but it carries the loss of the presurgical SLN mapping provided by [^99mTc]-based colloids. Hybrid tracers such as ICG-[^99mTc]Tc-albumin nanocolloid combine the benefits of both components. The aim of this study was to evaluate the feasibility and applicability of this hybrid tracer injected by transvaginal ultrasound-guided myometrial injection of radiotracer (TUMIR) approach in the detection of SLNs in patients with intermediate- and high-risk EC.

Methods: Fifty-two patients with intermediate- and high-risk EC underwent SLN biopsy after injection of a hybrid tracer using the TUMIR approach, followed by pelvic and paraaortic lymphadenectomy. SLNs were detected preoperatively by lymphoscintigraphic study and intraoperatively by gamma probe and near-infrared (NIR) optical laparoscopic camera.

Results: Preoperative lymphatic drainage was obtained in 69% and intraoperative detection in 71.4% of patients. A total of 146 SLNs (4.17 SLNs/patient) were biopsied. Pelvic bilateral detection was observed in 57% of the women and paraaortic drainage in 34% of the patients. The radioactive component allowed the detection of SLN in 97.1% of the patients, while the fluorescent component detected 80%. In more than 17% of the patients with intraoperative detection, SLNs were detected only by the radioactive signal. Lymph node metastasis was identified in 14.3% of patients submitted to SLNB. The sensitivity and negative predictive value for metastatic involvement were 100%.

Conclusion: TUMIR injection of a hybrid tracer in patients with intermediate- and high-risk EC combines the benefits of the radiotracer and the fluorescence methods with a single tracer. The method increases the paraaortic detection rate and allows a potential increase in SLN detection. Notwithstanding, based on our findings, the radioactive component of the hybrid tracer cannot be obviated.

Keywords: Endometrial cancer; Hybrid tracer (ICG-[99mTc]Tc-albumin nanocolloid); ICG; Lymphatic mapping; Radiotracer; Sentinel lymph node.