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

Melanoma

Magnetic tracer, Sentinel lymph node, Melanoma, MRI

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.

Rationale: 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. Objective: 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. A secondary objective is to assess the feasibility and diagnostic accuracy of SPIO/magnetometer (Sentimag®, Endomagnetics Ltd.) in comparison with dual trace gold standard (99mTc and PB) in SLN procedures in melanoma patients. Study design: A prospective single-arm feasibility study will be performed at the department of Surgical oncology at Zuyderland Medical Center Sittard, the Netherlands. Study population: Adult patients (≥18 years) with primary melanoma stage I-II and an indication for wide local excision (1 cm) and SLN procedure will be included in the study. Intervention (if applicable): All patients will undergo lymphatic mapping with a SPIO tracer (Magtrace®), 99mTc and PB. Main study parameters/endpoints: The concordance in SLN detection rate (sensitivity and specificity) of SPIO/MRI and LS and SPECT/CT using 99mTc. The concordance in SLN detection rate (sensitivity and specificity) of SPIO/magnetometer and the gold standard dual trace technique using 99mTc/Gamma probe and PB. Additionally, the number of post-injection (skin) reactions, complication and adverse events will be noted.

No related papers found yet.

Netherlands