Melanoma is a deadly form of skin cancer, with about 160,000 newcases diagnosed around the world each year.

Arising from research that began in the laboratories at the Australian Nuclear Science and Technology Organisation (ANSTO) in Sydney, CRCBID researchers have successfully developed a novel radiotracer, known as MEL050, that has the potential to assess the spread of melanoma in patients by targeting melanin in the tumours.

Based on in vitro and pre-clinical imaging work conducted at bothANSTO and Peter MacCallum Cancer Centre in Melbourne, papers on the synthesis method for MEL050, and the subsequent pre-clinical imaging results, were published in 2009 and 2010. After appropriate toxicology tests in animals, a first time in humans phase 0/1 clinical trial began at Peter MacCallum Cancer Centre in Melbourne in June 2010 and is scheduled for completion in June2011. The trial is sponsored by CRCBID, which successfully steeredthe trial through the rigorous human ethics approval process that is required prior to a clinical trial being conducted.

Results from the scans conducted using MEL050 to date are verypositive. Importantly, there have been no adverse events in thepatients. Also, the scans conducted using MEL050 show that in humans, the tracer accumulates in tumours that contain melanin. Further work is underway to conduct a first time in human study of MEL050 as a lymphoscintigraphic agent, allowing images to be captured of how the tracer moves through the lymph nodes. If the imaging approach works effectively, the results will give an indication of the distribution of melanoma cells, assisting to guide surgery.

These images show a patient who has had a scan using MEL050 to identify the spread of melanoma through the body.

The CT image on the left identifies the location of the melanoma metastasis in an enlarged right axillarylymph node. The image on the right illustrates the improved diagnostic value that the combined PET/CT scan offers doctors and patients through better definition of the tumour’s location, size and spread. The intense uptake of the tracer seen in the bladder confirms that MEL050 is cleared by the body mainly through the kidneys and that there is only low uptake in important tissues such as the liver and bone marrow, which are potential sites of secondary spread of melanoma.

image courtesy Peter MacCallum Cancer Centre