This year, about 134,000 Australians will be diagnosed with cancer. For many of them, the chemotherapy drugs they use to fight their disease will contain platinum.
“Platinum’s benefits for cancer were discovered by chance,” Dr Christine Carrington, a scientific advisor to the Cancer Council, says. “Bacteria was in a solution with platinum electrodes and scientists saw the bacteria had stopped replicating, then realised it was the platinum compound in the solution that was playing a role.”
Platinum was first trialled in chemotherapy medication in 1971, and within a decade it was widely used in a form of the drug cisplatin, which works by interacting with and binding to the DNA – “the platinum compound attaches itself to the DNA of the cancer and kills it off,” Carrington says. It came with serious side effects, from kidney damage to hearing loss, but also hugely improved survival rates. In recent decades, platinum-containing drugs such as carboplatin and oxaliplatin have been refined to reduce the side effects.
Cisplatin is now primarily used to treat testicular cancer and some head and neck cancers; carboplatin is used to treat lung cancer; and oxaliplatin is used to treat colorectal cancers.
These kinds of drugs are given as an infusion into the vein and Carrington says they look nothing like the polished platinum we see in jewellery stores, but are infinitely more valuable.