Circulating melanoma cell detection
Melanoma is a highly aggressive form of skin cancer. Mortality is high due to frequent metastasis of the tumour; melanoma is largely resistant to current drug strategies and so the cure rate for metastatic melanoma is currently less than 20%. Once melanoma has metastasised, the average survival is 6-9 months, with a 5 year survival rate of less than 40%.
Current staging parameters (including the TNM system) are largely based upon pathological evaluation of the primary tumour and are not sufficiently adequate for predicting the occurrence and outcome of metastatic disease in an individual patient. No clinical tests utilise measures of the circulating tumour cells that gives rise to the metastases. Metastasis related deaths can occur more than 35 years after diagnosis indicating that disseminated tumour cells may stay quiescent for decades and change their biological behaviour at any time. The inability to accurately predict melanoma progression, and thus the low cure rates, may be related to the fact that the majority of studies use primary and less often, metastatic tumour tissue to stratify patients. There is an urgent need for more detailed analyses of circulating tumour cells in order to provide an early identification of patients at risk of metastasis and an estimate of their prognosis.
To develop a prognostic blood test for melanoma.
To do this we test for markers of circulating melanoma cells in patient peripheral blood. Gene expression specific for melanocyte and melanoma cells is assessed and quantified relative to clinical disease stage. Results to date indicate that increasing numbers and levels of markers of circulating melanoma cells correspond to increasing disease stage.
Results to date
A blood test has been developed and tested in 300 melanoma patients at various clinical stages relative to 100 healthy controls. Blood has been analysed at time of surgery and one or more years after surgery. Techniques and methodologies have been optimised.
Results consistently show that:
- marker positivity can be accurately identified in peripheral blood from melanoma patients compared to healthy controls;
- markers correlate closely with diagnosis of metastatic melanoma; and
- patients are significantly more likely to be positive for multiple markers than healthy controls.
Funding and sponsorship
This research has been funded by the Cancer Council of WA, the NHMRC and by donations from many community sponsors. We thank you all
- JW trust (Jenny Fairweather and Katrina Burton)
- Mr and Mrs Peter Twine
- Mr and Mrs Richard and Sheree Lawrence
- Sheila and Lazar
- Ms Wendy Pritchard
- Karen Zielinski and Riccardo Rizzi
- Philip Ian Cooper
- Dave Parsonson
- Mrs CM Little
- Pam Warren
- Paige S
- Colin and Helen Jameson
- Mrs. D Joyner
- Graeme Robertson
- G and L Fernie
- Alexander Gorge Wilson
- A.M. Moore
- Helen Tyler
- Mr. L Spark
- Darren Webb
- Paul Jansz
- Macmahon Building Company
- Calabrese Club
- Glynn and Sheila Rowland
- Ross Squire Homes
- Dale Alcock Homes
Principal Investigator, Associate Professor Mel Ziman
Ms Anna Reid
The University of Western Australia and Cancer Council, Professor Michael Millward
Perth Melanoma Clinic, Associate Professor Robert Pearce
Sir Charles Gairdner Hospital, Mr Mark Lee
University of Cambridge, Dr Stan Lazic
Mr Peter Matthews