A new technique for melanoma diagnosis and treatment

A more flexible staging standard

During melanoma treatment, it is important to assess whether the cancer has spread to the lymph nodes. The first lymph nodes where cancer cells are most likely to spread to are called sentinel lymph nodes (SLNs). Using the Sentimag^® - Magtrace^® magnetic localisation system, SLNs can be identified effectively while avoiding issues related with radioactive materials [2-3].

The procedure

In order to identify the SLNs during surgery, the surgeon injects a small amount (just up to 2 ml) of Magtrace^® tracer into the skin close to the cancer or the scar tissue. After injection, the Magtrace^® tracer will flow through the lymphatic system and will ‘mark’ the SLNs.

The injection can happen up to 30 days prior to surgery or in the operating theatre after the patient undergoes anaesthesia. During the surgical procedure, the surgeon will use the Sentimag^® probe to identify the marked SLNs, which will be removed and sent to the pathology lab for analysis.

Benefit

The Magtrace^® tracer is an established technique that has been used in over 65,000 cases. It enables more flexibility and convenience for both patients and physicians as it can be injected within a 30-day window.

Treatment solutions in melanoma - precisely bring to light what needs to be seen

Melanoma is often considered one of the most aggressive and treatment-resistant human cancers [4]. In the past few years, the therapeutic landscape of melanoma has been revolutionised by immunotherapies and targeted therapies. Both strategies have shown markedly improved survival compared with the use of chemotherapy regimens [5].
Precision diagnostics are key to selecting the right therapy at the right time for the right cancer patient.

Gene alterations play a key role during the onset and development of melanoma [6]. Therefore, reliable assessment of the tumour’s mutational status is decisive not only in selecting cancer patients eligible for targeted therapy, but also later on to monitor response to treatment and disease progression.
To investigate such genetic changes, oncologists can make use of a variety of molecular genetic tests which may support them in making personalised treatment decisions.

Sysmex offers a range of products based on cutting-edge molecular biology technologies supporting heath care professionals and patients along the whole pathway of care.

Molecular tests for therapy selection

CytoCell FISH (Fluorescent In Situ Hybridization) probes targeting genes in chromosomes 6 and 11 (RREB1, MYB and CCND1) are used to aid pathologists and clinicians in differentiating benign versus malignant melanocytic lesions.

BRAF, NRAS, KIT and NF1 are among the most common mutated genes underlying the pathogenesis of melanoma that can be investigated by next generation sequencing (NGS) tests. The Sysmex solution to help characterise the overall genomic landscape of melanomas is SureSeq myPanel^TM* NGS Custom Melanoma Cancer Panel.

For first-line treatment particularly in BRAF wild-type patients, immunotherapy with PD-1 antibodies alone or in combination with CTLA-4 antibodies should be considered [7]. While the combination of dabrafenib/trametinib is one of the standards of care for adjuvant BRAF-mutated melanoma patients and was approved by the European Medicines Agency for adjuvant treatment for melanoma in August 2018 [5].

Liquid biopsy for monitoring

Analysing genetic mutations in biopsied tissue has been the standard in clinical oncology, despite its inconvenience and risks of clinical complications for the patients [8]. Moreover, biopsies can be subject to selection bias due to tumour heterogeneity, can be difficult to obtain in sufficient amounts and the information provided is restricted to a static time point. [9, 10]. Here, liquid biopsy analysis of mutations in cell-free tumour DNA (ctDNA) has become a valuable tool for a variety of clinical and investigative applications. The detection of clinically relevant mutations from a simple blood draw enables clinicians to monitor the patient’s response to therapy in real time by repeated sampling throughout the whole course of treatment and allows early identification of upcoming resistances.

Plasma-SeqSensei™ Melanoma RUO Kit is a highly sensitive NGS-based assay allowing researchers to detect mutations on the two relevant genes NRAS and BRAF.

* SureSeq myPanel^TM: For research use only; not for use in diagnostic procedures.