Sentinel lymph node detection in thyroid carcinoma using [68Ga]Ga-tilmanocept PET/CT: a proof-of-concept study

• Published in: European journal of nuclear medicine and molecular imaging Vol. 51; no. 2; pp. 512 - 520
• Main Authors: de Vries, Lisa H., Lodewijk, Lutske, Ververs, Tessa, Poot, Alex J., van Rooij, Rob, Brosens, Lodewijk A. A., de Krijger, Ronald R., Rinkes, Inne H. M. Borel, Vriens, Menno R., de Keizer, Bart
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.01.2024; Springer Nature B.V
• Subjects: Biopsy; Cancer; Cardiology; Computed tomography; Gallium Radioisotopes; Humans; Imaging; Injection; Lymph nodes; Lymph Nodes - pathology; Lymphatic Metastasis - diagnostic imaging; Lymphatic Metastasis - pathology; Lymphatic system; Lymphoscintigraphy - methods; Medicine; Medicine & Public Health; Metastases; Nuclear Medicine; Oncology; Original; Original Article; Orthopedics; Positron emission; Positron Emission Tomography Computed Tomography; Radiology; Radiopharmaceuticals; Sentinel Lymph Node - surgery; Sentinel Lymph Node Biopsy - methods; Thyroid cancer; Thyroid carcinoma; Thyroid Neoplasms - pathology; Tc-nanocolloid; ICG; Sentinel lymph node; Ga-tilmanocept PET/CT; Thyroid carcinoma; 68Ga-tilmanocept PET/CT; ICG-99mTc-nanocolloid
• ISSN: 1619-7070; 1619-7089
• DOI: 10.1007/s00259-023-06449-0

Purpose Sentinel lymph node (SLN) biopsy is rarely used for thyroid carcinoma staging. This is due to challenges associated with conventional Tc-99m-labeled tracers, often producing a large hotspot at the injection site, potentially hiding nearby SLNs (shine-through effect). The aim of this study was to demonstrate the feasibility and effectiveness of SLN visualization using the new PET tracer [ 68 Ga]Ga-tilmanocept. Methods Patients with thyroid carcinoma underwent ultrasound-guided peritumoral injection of [ 68 Ga]Ga-tilmanocept and ICG-[ 99m Tc]Tc-nanocolloid. [ 68 Ga]Ga-tilmanocept PET/CT scans were conducted at 15 min and 60 min post-injection to visualize the SLNs. SLN biopsy was performed using ICG-[ 99m Tc]TC-nanocolloid for intraoperative identification. The corresponding lymph node level was resected for reference. Results Seven differentiated thyroid carcinoma (DTC) and 3 medullary thyroid carcinoma (MTC) patients were included, of which 6 were clinically node-negative. The median number of SLNs detected on [ 68 Ga]Ga-tilmanocept PET/CT and resected was 3 (range 1–4) and 3 (range 1–5), respectively. Eight SLNs were found on PET/CT in the central compartment and 19 in the lateral compartment. The SLN procedure detected (micro)metastases in all patients except one. Seventeen of 27 pathologically assessed SLNs were positive, 8 negative, and 2 did not contain lymph node tissue, which led to upstaging in 5 out of 6 clinically node-negative patients. Conclusions [ 68 Ga]Ga-tilmanocept PET/CT identified SLNs in all patients, mainly in the lateral neck. The SLNs were successfully surgically detected and resected using ICG-[ 99m Tc]Tc-nanocolloid. This technique has the potential to improve neck staging, enabling more personalized treatment of thyroid cancer according to the lymph node status. Trial registration 2021–002470-42 (EudraCT).