The research, published in Nature Cancer, is a joint study led by Harvard Medical School in collaboration with researchers from The University of Sydney, Melanoma Institute Australia, Sydney Local Health District and Adaptive Biotechnologies.
The researchers analysed primary melanoma samples (lesions removed from the original melanoma site) from 209 patients, 164 of whom came from Melanoma Institute Australia. In particular, they focused on a subset of immune cells known as T cells.
They found that patients with a T-cell fraction (TCFr or proportion of cells in the lesion that were T cells) of less than 20 percent in their primary melanoma were two-and-a-half times more likely to have disease progression than those with more than 20 percent TCFr.
The study was jointly led by Sydney Vital member Dr James Wilmott from the University of Sydney and Melanoma Institute Australia, with researchers from Harvard Medical School.
“These findings suggest analysing TCFr in primary melanomas is a valuable tool for predicting which patients are at risk of developing metastatic melanoma. This test offers the ability to identify primary melanoma patients at high risk of developing metastatic disease at their initial diagnosis. These patients may benefit from close monitoring or the addition of adjuvant treatments to prevent their disease progressing.” said Dr Wilmott.
Australia has one of the highest rates of melanoma in the world, with one person diagnosed every 30 minutes and one person dying every five hours from the disease.
While 90 percent of early stage melanomas are cured with surgery alone, it will recur metastatically in some patients within five years.