It’s a type of leukemia so rare that only about one in every 550,000 people are diagnosed in Australia each year.
So when Greg Waters heard someone from his old street was battling the illness, he reacted with disbelief.
But the giveaway was that they both were treated with arsenic – a chemical best known as a poison, but one that has produced dramatic results in the treatment of acute promyeloid leukaemia (APML).
Mr Waters and Michelle Gilchrist are two of 49 cancer cases over the last 15 years on Cabbage Tree Road, which crosses Williamtown’s contamination “red zone”.
Mr Waters is in remission after being diagnosed with APML six years ago, at the age of 39. He is now based in Tanilba Bay but lived on the road as a child.
Ms Gilchrist, 50, is still going through treatment for the disease, which she was diagnosed with last year. Her home is in a heavily polluted part of Cabbage Tree Road.
A diagnosis with APML is considered a medical emergency because, without treatment, it has a median survival of less than a month.
However, medical advances over the last few decades have had a remarkable effect on survival rates. Once the deadliest form of leukemia, it is now the most curable.
It was through a routine trip to the blood bank that Mr Waters discovered he had the condition; his white blood cell count was abnormal. Within 24 hours, he was having chemotherapy at the Mater Hospital.
“It was absolutely a shock,” he said. “I had a month of chemotherapy followed by two months of arsenic treatment. I had to drive into the hospital for six hours a day for them to pump arsenic into my veins.”
When asked about the Cabbage Tree Road cases, specialists were circumspect.
Professor Phil Rowlings, director of Haematology at the University of Newcastle, admitted it was “always a little bit unusual” to find two patients with same rare illness in the same street or suburb.
“But sometimes it’s a one off. There is maybe a one in a million chance of someone winning the lottery, but things that are really rare do happen,” he said.
Ms Gilchrist’s husband, Greg, was unsure about any connection between the cancers but described the situation as “getting weirder”.
“Scientifically, I don’t know,” he said. “But when I saw that it had got to 49 cases in 15 years, it’s sort of getting a bit overwhelming.”
According to Professor Harry Iland from the University of Sydney’s medical school, the situation with Mr Waters and Ms Gilchrist was uncommon, but was “probably a random event”.
“I don’t think you can tell with such small numbers,” he said.
He said there was no known cause of APML, aside from where the patient had previously undergone treatment for another type of cancer.