Sentinel lymph node detection in oral cancer: a within-patient comparison between [99mTc]Tc-tilmanocept and [99mTc]Tc-nanocolloid

Abstract

Purpose Sentinel lymph node (SLN) biopsy has proven to reliably stage the clinically negative neck in early-stage oral squamous cell carcinoma (OSCC). [99mTc]Tc-tilmanocept may be of benefit in OSCC with complex lymphatic drainage patterns and close spatial relation to SLNs. Methods A prospective within-patient evaluation study was designed to compare [99mTc]Tc-tilmanocept with [99mTc]Tc-nanocolloid for SLN detection. A total of 20 patients with early-stage OSCC were included, who underwent lymphoscintigraphy with both tracers. Both lymphoscintigraphic images of each patient were evaluated for SLN detection and radiotracer distribution at 2–4 h post-injection. Results The injection site’s remaining radioactivity was significantly lower for [99mTc]Tc-tilmanocept (29.9%), compared with [99mTc]Tc-nanocolloid (60.9%; p < 0.001). Radioactive uptake in SLNs was significantly lower for [99mTc]Tc-tilmanocept (1.95%) compared with [99mTc]Tc-nanocolloid (3.16%; p = 0.010). No significant difference was seen in SLN to injection site ratio in radioactivity between [99mTc]Tc-tilmanocept (0.066) and [99mTc]Tc-nanocolloid (0.054; p = 0.232). A median of 3.0 and 2.5 SLNs were identified with [99mTc]Tc-tilmanocept and [99mTc]Tc-nanocolloid, respectively (p = 0.297). Radioactive uptake in higher echelon nodes was not significantly different between [99mTc]Tc-tilmanocept (0.57%) and [99mTc]Tc-nanocolloid (0.86%) (p = 0.052). A median of 2.0 and 2.5 higher echelon nodes was identified with [99mTc]Tc-tilmanocept and [99mTc]Tc-nanocolloid, respectively (p = 0.083). Conclusion [99mTc]Tc-tilmanocept had a higher injection site clearance, but at the same time a lower uptake in the SLN, resulting in an SLN to injection site ratio, which was not significantly different from [99mTc]Tc-nanocolloid. The relatively low-radioactive uptake in SLNs of [99mTc]Tc-tilmanocept may limit intraoperative detection of SLNs, but can be overcome by a higher injection dose.

What is the role of sentinel lymph node biopsy in the management of oral cancer in 2020?

“…A recent prospective within-patient evaluation study compared 99mTc Tc-tilmanocept with 99m Tc-nanocolloid for SLN detection in 20 patients with early-stage OSCC, who underwent lymphoscintigraphy with both tracers. 99m Tctilmanocept had a higher injection site clearance, but at the same time, a lower uptake in the SLN, resulting in a comparable SLN to injection site ratio, using 99m Tc-nanocolloid [51]. 99m Tc-tilmanocept is registered at the FDA and EMA using an activity of 74 MBq, which is lower than activities routinely used with 99m Tc-nanocollidal tracers.…”

Novel Diagnostic Approaches for Assessment of the Clinically Negative Neck in Head and Neck Cancer Patients

“…Several other potential tracers and imaging modalities for SLN identification have been suggested. An alternative radioactive agent, 99m Tc tilmanocept, is characterized by a rapid injection site clearance, high retention within the SLN and lesser drainage to higher echelon lymph nodes and can therefore be particularly beneficial in flour of mouth tumors to overcome the shine-through effect ( 89 , 90 ). A multicenter study investigating 99m Tc tilmanocept for SLNP in a cohort of HNSCC patients yielded an overall accuracy rate of 98.8% in correctly determining the pathological lymph node status of the neck.…”

The Efficacy of Radionuclide Imaging Techniques at Sentinel Node Identification in Patients with Cutaneous Melanoma

“…Первая группа РФП широко распространена в странах Европы, США, Австралии и Канаде, а также в РФ (доступны 99m Тс-технефит, 99m Тс-алотех, 99m Тс-нанотоп) [11]. Вторая группа препаратов представлена менее широко (Лимфосик/ Lymphoseek), однако в литературе сообщается об их клиническом применении и возможных преимуществах [12].…”

“…Основные преимущества метода по сравнению с указанным выше исследованы и определены на пациентах с меланомой кожи различной локализации. Способность лучше отображать пути лимфодренажа (в особенности нетипичные локализации СЛУ) и бóльшая чувствительность в обнаружении были неоднократно продемонстрированы [10][11][12][13][14][15].…”