Light therapy offers hope for deadly cancer
A light therapy used to treat skin cancer and sun spots is emerging as a promising treatment for reaching cancer cells deep in the body, with Melbourne researchers finding the first evidence of its ability to kill ovarian tumours.
Ovarian cancer is notoriously deadly given its vague symptoms lead it to be typically diagnosed in the advanced stages.
Less than half of these women will live more than five years after diagnosis, as most patients ultimately become resistant to standard chemotherapies.
But new research from the Hudson Institute of Medical Research has found that a new type of treatment called photodynamic light therapy is able to dramatically shrink ovarian cancers in mice, while sparing the surrounding healthy tissue.
The treatment works by giving the patient a drug containing light-sensitive compound; this is administered intravenously for solid tumours, and as a skin cream for treating melanoma.
These compounds sit inert in the cancer cells until a specific wavelength of light is shined on them, causing a reaction in the tumour.
The proof of concept work in mice - using a new type of the light therapy called Photosoft Technology developed by Victorian medical technology Invion - saw it able to halve the size of ovarian tumours in mice by three weeks.
Lead researcher Dr Andrew Stephens, head of the Hudson's ovarian cancer biomarker laboratory, said it was believed the treatment worked in two ways; first by triggering instant cell death and secondly by rallying the immune system to continue attacking the cancer.
"It's like a little explosion in the cell that damages the cancer cell and it dies immediately," Dr Stephens said.
"Over the next few weeks we believe it starts to recognise the tumour as bad and continues to attack it and remove it. That's something we'll be looking at over the next few months."
Dr Stephens said given ovarian cancer was resistant to traditional and some new types of treatment - such as immunotherapy, which was revolutionising outcomes for blood cancer and melanoma - this looked like a new and promising way of evoking the immune system to provide a more sustained attack against the cancer.
"Ovarian tumours are very good at suppressing and hiding from the immune system," he said.
"They key outcome from this work is we've really got potentially another string in the bow where conventional therapies aren't working."
The Photosoft Technology will be tested in the first Australians with skin cancer from next year, with the aim of offering a less painful treatment with minimal scarring.
Peter MacCallum Cancer Centre will also test the experiment treatment next year in animal models of anal cancer.