Radiotherapy under-use costing lives
Under-use of radiotherapy is putting cancer patients at risk of cancer recurrence and death, new research shows, with significant treatment gaps identified in breast and rectal cancer.
New research funded by the Cancer Institute of NSW compared the uptake of radiotherapy for different cancers in NSW in 2009-11 with optimal rates, determined using evidence-based guidelines.
The modelling study found that only 59% of NSW breast cancer patients received radiotherapy, compared with an optimal rate of 88%. Across the three year cohort, this led to an estimated 87 excess deaths (overall survival detriment) as well as 652 additional patients without local control of their cancers five years after diagnosis.*
Likewise, for rectal cancer, the actual rate of radiotherapy was 34% compared with an optimal rate of 55%. This led to an estimated 55 excess deaths across the three year cohort and 180 additional patients without local control at five years post-diagnosis.*
For melanoma, the actual and optimal radiotherapy rates were 4% and 15% – leading to 276 additional patients without local control at five years, but no survival detriment.*
The findings were presented at the Annual Scientific Meeting of the Clinical Oncology Society of Australia in Perth this week, based on data from 13,311 breast cancer patients, 3,628 rectal cancer patients and 10,769 melanoma patients.
Patients were more likely to miss out on radiotherapy if they were older, had more advanced tumours or had a longer travelling distance to the nearest treatment facility, the study found.
Breast and rectal cancers, areas for improvement
Study co-author Professor Geoffrey Delaney, a conjoint professor at the University of NSW and Western Sydney University, said the study highlighted breast cancer and rectal cancer were two areas to focus on to improve radiotherapy utilisation.
“The overall survival benefit conferred by radiotherapy in breast cancer patients is not that much compared with chemotherapy, but because of the large number of patients with breast cancer, the number of deaths likely to be prevented by radiotherapy in this group is relatively high,” he said.
Professor Delaney said the treatment gap observed in the study was likely to result from a wide range of factors, including patient choice, referring doctors’ perceptions of the benefit of radiotherapy, patient age and socio-economic status, the presence or absence of other chronic disease and access issues.
“The next step is to survey patients to find out if they didn’t have radiotherapy, then why not,” he said.
Professor Delaney acknowledged the study had limitations, including the potential that it was “too optimistic” about the benefits of radiotherapy.
“Our modelling took into consideration the presence of comorbidities that might prevent patients having radiation, however there may still be other good reasons for not having radiotherapy that the model did not take into account,” he said.
Professor Fran Boyle, an oncologist at Sydney’s Mater Hospital and Director of the Patricia Ritchie Centre for Cancer Care and Research, said the research was “interesting and very topical”.
“There potentially are barriers to people accessing radiotherapy, and it would appear that part of the problem is the sheer number of people with breast cancer,” she said.
Professor Boyle said she was hopeful that radiotherapy use may be individualised for breast cancer patients in future, using MRI and gene profiling to target treatment toward patients most likely to benefit.
“For instance, older patients with smaller hormonal cancers have a lower risk of recurrence when taking endocrine therapy tablets, and it has been suggested that they may not require radiotherapy,” she said. “This is now the subject of the EXPERT trial, which is currently recruiting.”
The under-use of radiotherapy among cancer patients living further from treatment centres has long been known.
Professor Delaney said it was good news then, that a sub-study by his group had linked the opening of five new radiotherapy departments – including four in regional NSW – with an increase in radiotherapy utilisation among cancer patients.
In 2004 – 2006, before the radiotherapy facilities opened in Coffs Harbour, Port Macquarie, Lismore, Orange and Macquarie University Hospital, 26% of cancer patients in the state received radiotherapy. In 2009-11, after the new facilities had opened, the radiotherapy utilisation rate had increased to 29%. According to the researchers’ benchmark, the optimal rate is 48%.
Professor Delaney said it would be reasonable to expect further increases as the new facilities became more established.
NSW Health said construction of rural cancer centres over the last decade meant 95% of the state’s residents now lived within 100km of a treatment facility.
*Annual estimates could be derived by dividing figures for the three-year cohort by three, the authors said. In breast cancer this worked out as 29 excess deaths annually and 217 additional patients each year without local control at five years. In rectal cancer this would mean 18 excess deaths annually and 60 additional cases each year without local control at five years. In melanoma there would be 92 additional patients each year without local control at 5 years.