One dose of spinal radiation as effective as five for cancer patients with spinal canal compression, study suggests
The results of a large, comparative effectiveness clinical trial suggest that a single dose of radiotherapy may be as effective as five for end-of-life metastatic cancer patients experiencing spinal canal compression.
An international team of researchers from the UK and Australia has conducted a large, comparative effectiveness clinical trial involving 686 end-of-life metastatic cancer patients experiencing spinal canal compression. The results of the investigation suggest that a single dose of radiotherapy may be as effective as five for preventing ambulatory status amongst this patient cohort.
Approximately 3–5% of individuals with metastatic cancer that spreads to their spines experience painful spinal canal compression. UK guidelines do not currently stipulate a standard treatment regimen for these patients, though most will receive several radiotherapy doses – or ‘fractions’ – to alleviate their pain and symptoms, which require multiple consecutive hospital visits.
For this study, researchers recruited a total of 686 metastatic cancer patients with spinal canal compression from 47 radiotherapy centers across the UK and Australia. 50% of patients were randomized to receive a single radiotherapy dose, whilst the remaining half of patients received five doses, which required hospital visits for five consecutive days.
Patients’ abilities to walk unaided were assessed by determing their ambulatory grade statuses at 1, 2, 4, 8 and 12 weeks after they commenced their randomized radiotherapy regimens.
8 weeks after starting radiotherapy, 342 study participants were still alive. Of these, 69% of patients (115 out of 166) who had received single-fraction radiotherapy were classified as ambulatory garde I or II, compared to 73% of patients (128 of 176) who had received five radiotherapy doses. This difference was not considered statistically significant.
At 12 weeks post radiotherapy commencement, 72% of patients who had received one dose of radiotherapy were able to walk, compared to 68% of individuals who had been given five fractions.
Further, at the 12-week stage, various secondary patient outcomes – including quality of life and pain scores – were similar amongst patients who had received one or five radiotherapy fractions.
Radiation therapy can also be associated with unpleasant side effects; smaller proportions of patients who received single fractions of spinal radiation experienced adverse skin reactions or fatigue compared with study participants who received five radiotherapy doses.
However, an important study limitation concerns the significant proportion of patients who were not alive 8 weeks post therapy commencement – the time when the primary study outcome was evaluated. Further, patients who had radiation treatment to lower regions of their spinal cords – specifically the cauda equina – had increased likelihoods of experiencing bladder problems. Importantly, for this subset of patients, one radiotherapy dose may not constitute enough treatment.
Nevertheless, lead study author Peter Hoskin (University of Manchester; UK and Mount Vernon Cancer Centre; Northwood, United Kingdom) stated: “We believe our findings, which show equal clinical effectiveness for single-dose radiotherapy, provide strong evidence for NICE guidelines, and those in other countries, to be changed to stipulate a one-dose one-visit approach, reducing unnecessary discomfort for end-of-life cancer patients without compromising efficacy.”
Hoskin PJ, Hopkins K, Misra V et al. Effect of single-fraction vs multifraction radiotherapy on ambulatory status among patients with spinal canal compression from metastatic cancer. JAMA.; 322(21); 2084–2094; (2019);