Study results presented at the 2021 annual meeting of the Orthopaedic Research Society (12–16 February, virtual) report that a radioactive bone cement could provide a safer alternative to conventional radiation therapy for bone tumours.
The study was conducted at the University of California, Irvine (UCI; Irvine, USA). Researchers used animal and computation studies to evaluate the short-term safety of injecting brachytherapy cement into vertebrae; the possible migration of radioactivity into blood, urine or faeces; the dose rate outside the injection site; and the radiation dose from phosphorus-32 emissions to the spinal cord and soft tissue.
According to researchers, at 12 weeks post-injection physical examinations were normal and they found no evidence of the phosphorus-32 isotope circulating in the blood, and no changes in blood work related radioactivity or neurological deficits.
Lead researcher Joyce Keyak, UCI professor of radiological sciences, commented, “This localised treatment for bone tumours stays localised, and we did not see any effects outside the bone.” She continued, “This is important because traditional radiation therapy causes adverse effects such as nausea, vomiting and diarrhoea.”
According to a press release from UCI, current treatments for this cancer include multiple sessions of external beam radiation on the spine. UCI adds that in addition to the unpleasant side-effects of radiation, the treatment can threaten the spinal cord and weaken the bones already compromised by a tumour’s erosion, increasing the risk of fracture.
“Brachytherapy cement could be used without delay in a convenient, one-step, minimally invasive treatment to irradiate tumours,” Keyak said, “and would not irradiate the spinal cord or limit future treatment options.”
Keyak noted that brachytherapy bone cement does not have the same side-effects as radiation therapy because the injection directly targets the tumour and radiation does not pass through other organs, such as the intestines or stomach. According to Keyak, a bone cancer patient may need 10 or more sessions of radiation therapy, but with the brachytherapy bone cement a single injection can provide an equivalent, targeted tumour treatment with significantly less threat to the spinal cord and nerves.
Brachytherapy cement was created by Keyak and Harry Skinner (St. Jude Heritage Medical Group, Corona del Mar, USA), by infusing bone cement with radioactive material used in other treatments. The product is produced by their company Bone-Rad Therapeutics, and has four patents and one patent pending.
The next step, Keyak said, will be more animal studies, followed by an application for a clinical trial.