Exploring an Alternative Pre-operative SLN Mapping Method Using a Magnetic Tracer and MRI for Melanoma Patients

Sentinel lymph node biopsy (SLNB) is crucial in the management of malignant melanoma treatment and is currently performed by pre-operatively inject a colloid nanomaterial labeled with Technetium (99mTc) as radioactive tracer. Intra-operatively, Patent Blue (PB) will be injected to improve the visualization of the lymphatic tract. However, current pre-operative SLN mapping technique is associated with disadvantages as radiation exposure for both patients and health care staff and logistic challenges, because of time constraints due to short half-live time of 99mTc. Superparamagnetic iron oxide (SPIO) is a non-radioactive technique using a magnetic tracer (Magtrace® (Endomagnetics Ltd.)) to identify SLNs. Several studies showed that SPIO is non-inferior to dual tracing with 99mTc and PB in breast cancer patients. SPIO is expected to be non-inferior to dual tracing with 99mTc and PB in melanoma patients. However, further research is needed to demonstrate the use of SPIO in pre-operative MRI scanning. The primary objective of this study is to evaluate the feasibility and diagnostic accuracy of pre-operative MRI scanning using SPIO compared to lymphoscintigraphy (LS) and single-photon emission computed tomography/computed tomography (SPECT/CT) using 99mTc for identifying SLN status in melanoma patients.

Sex

All

Minimum age

18 Years

Inclusion Criteria:

* Patients ≥18 years of age at the time of consent;
* Histological confirmed melanoma (patient must have primary cutaneous melanoma with Breslow thickness ≥ 0.8-2.0mm with or without ulceration or \<0.8mm with ulceration (pT1b - pT2b, AJCC 8th edition));
* Indication for wide local excision (margin 1 cm) and SLN procedure;
* Patients should be willing and able to provide informed consent.

Exclusion Criteria:

* Intolerance/hypersensitivity to 99mTc-nanocolloid, PB, iron or dextran compounds;
* Iron overload disease;
* Pregnant or breast-feeding women;
* Previous surrounded lymph node surgery;
* Patients with head and neck melanomas;
* Standard MRI exclusion criteria;
* Implantable (electrical) devices (e.g. pacemaker, cochlear implants, neurostimulator);
* Any other metal implants;
* Claustrophobia;
* MR-incompatible prosthetic heart valves;
* Patients who are unable or refuse to provide informed consent.