Detecting the sentinel lymph node in patients with differentiated thyroid carcinoma.

Area of Science:

• Oncology
• Nuclear Medicine
• Surgical Pathology

Background:

• Differentiated thyroid carcinoma (DTC) staging relies on accurate lymph node assessment.
• Sentinel lymph node (SLN) biopsy is a minimally invasive technique for nodal staging in various cancers.

Purpose of the Study:

• To assess the feasibility and accuracy of sentinel lymph node (SLN) mapping using technetium-99m nanocolloid in patients with differentiated thyroid carcinoma.
• To evaluate the efficacy of SLN detection in papillary versus follicular thyroid carcinoma subtypes.

Main Methods:

• Nine patients with suspected thyroid carcinoma underwent intratumoral injection of 37 MBq technetium-99m nanocolloid.
• Scintigraphic imaging and intraoperative gamma probe detection were used to identify and localize SLNs.
• Surgical excision of the primary tumor followed by SLN removal was performed.

Main Results:

• SLN identification was successful in all four patients with papillary thyroid carcinoma.
• SLN detection failed in both patients diagnosed with follicular carcinoma.
• One patient had no visible SLN on scintigraphy but three were identified intraoperatively with the gamma probe.
• No false-negative findings were reported in patients where SLNs were successfully mapped.

Conclusions:

• Sentinel lymph node mapping is a viable technique for staging papillary thyroid carcinoma.
• The current SLN mapping method demonstrated limitations in patients with follicular thyroid carcinoma.
• Further research with a larger patient cohort is recommended to validate these findings and refine the technique for different DTC subtypes.