First study on the efficiency of ^99mTc-rituximab for sentinel lymph node mapping and biopsy in oral squamous cell carcinoma

Objective: To explore the clinical efficiency of using the sentinel lymph node (SLN) imaging agent ^99mTc-rituximab for lymphoscintigraphy and SLN biopsy (SLNB) in oral squamous cell carcinoma (OSCC) patients.

Methods: A retrospective study was conducted on 23 patients with OSCC who underwent ^99mTc-rituximab lymphoscintigraphy and SLNB. The cohort comprised 16 men (69.6%) and 7 women (30.4%) with a median age of 64.0 years (range: 33-90 years). All patients received a preoperative peritumoral injection of ^99mTc-rituximab. The SLN detection rates (SDRs) of SLN imaging and SLNB were analyzed. The localizations of SLNs were counted. Patients were followed up after surgery. Differences were considered significant for a p-value of less than 0.05.

Results: The SDRs of lymphoscintigraphy and SLNB were 91.3% (21/23) and 100.0% (23/23), respectively. The SDRs of lymphoscintigraphy for patients in pathological stages I/II and III/IVa were 100.0% (15/15) and 75.0% (6/8), respectively. Among the 2 patients with negative imaging results, both were stage IVa and both had SLN metastasis. The SLNs were located in levels Ib, IIa, IIb, III, and IV, accounting for 45.0% (18/40), 40.0% (16/40), 10.0% (4/40), 2.5% (1/40), and 2.5% (1/40), respectively. The median follow-up duration was 32.0 months (range: 13.0-68.0 months). During follow-up, none of the 23 patients (100.0%) showed lymph node (LN) metastasis. As a result, the sensitivity, negative predictive value (NPV), and accuracy were all 100.0%.

Conclusions: The application of ^99mTc-rituximab for SLN imaging and SLNB in OSCC patients demonstrated high detection rates and accuracy, holding significant clinical value.