Christine O'Gorman is not expected to live beyond the end of the year after cancer in her left breast spread to her lungs and brain.
The 57-year-old from Moorebank had her breast removed, has undergone multiple rounds of chemotherapy and radiation, and is now taking painkillers for her symptoms.
In the New South Wales Supreme Court Wednesday, Justin Clifton Hoeben awarded Ms O'Gorman $405,990 in damages and costs after she sued Sydney South West Area Health Service, which operates BreastScreen.
"(Ms O'Gorman) realises and is trying to come to terms with the fact that there is no hope of a cure and that she must live her life as best as she can between now and the end of December when medical opinion assesses that she will die," Justin Hoeben said in his judgment.
"Her final weeks will involve considerable pain and suffering."
Ms O'Gorman had undergone routine mammograms every two years from 1994 at BreastScreen - a free service funded by the Commonwealth and NSW Governments.
Her 2002 and 2004 results detected a mass in her left breast, which reviewing doctors deemed had no suspicious features and had not increased in size between screenings.
She went for another screening in February 2006 and was not informed of any significant changes.
"I cannot, however, ignore my observation that on a simple visual comparison, the mass on the 2006 films appeared significantly larger than that of the 2004 films," Justice Hoeben said.
In early January 2007, Ms O'Gorman was on holiday when she scratched her left breast and noticed a lump.
She was treated with chemotherapy to shrink the tumour before it was removed and continued the cancer treatment until the end of July.
In August, she underwent further tests that revealed she had cancer in her lungs, and a week later she had a mastectomy.
In June of this year, tumours were detected in her brain, prompting further chemotherapy.
"The plaintiff has become depressed and describes herself as being sad all the time. She cries easily," Justice Hoeben said.
"Although she tries to put on a brave face for her partner (Glen) and (daughter) Christie, she is finding it harder to do."
Justice Hoeben ruled that BreastScreen was negligent by failing to compare Ms O'Gorman's 2004 and 2006 mammogram results and by not recalling her for further tests after her 2006 screening.
She was awarded $247,500 for general damages with the remainder of the award comprising out-of-pocket costs and the estimated loss of past and future earnings.
He also ordered the area health service to pay her legal costs.