In a small study reported in JAMA Network Open, D’Andrea et al found that diffusing alpha-emitter radiation therapy—a novel solid tumor management strategy using alpha-particle interstitial brachytherapy—appeared to be safe and showed activity in patients with recurrent or unresectable skin cancers.
Study Details
The study included 10 patients who underwent a 2- to 3-week treatment course and were followed for 24 weeks after treatment in 2021 and 2022 at two U.S. sites (University Cancer and Diagnostics Centers in Houston, and West Cancer Center and Research Institute in Germantown, Tennessee). An implanted diffusing alpha-emitter radiation therapy device was used to deliver a physical dose of 10 Gy to the tumor; devices were removed after 2 to 3 weeks.
Key Findings
Among the 10 patients, tumors were located on the nose, chin, eyelid, scalp, neck, trunk, and extremities. Median tumor volume prior to treatment was 2.1 cm3 (range = 0.65–12.65 cm3). All 10 patients were successfully treated with diffusing alpha-emitter radiation therapy. The mean prescription dose coverage of the gross tumor volume was 91%, with all tumors having coverage of ≥ 85%. The median duration of diffusing alpha-emitter radiation therapy was 15 days.
Overall, nine adverse events related to the procedure or treatment were observed; no grade ≥ 3 adverse events were reported, with grade 1 or 2 events consisting of three cases of radiation dermatitis and two cases of pruritus over the device implantation area, and one case each of localized edema, decreased joint range of motion, pain, and wound infection. A total of two serious adverse events—syncope and hypertension—occurred in a single patient; neither was considered procedure/treatment-related. No long-term toxicity was observed.
At 12 weeks after treatment, complete response was observed in all 10 patients (100%) at the site of device implant. Computed tomography at 24 weeks post-treatment showed no evidence of recurrent disease in any of the patients.
The investigators concluded, “This cohort study suggests the feasibility and preliminary safety of diffusing alpha-emitter radiation therapy in the management of recurrent or unresectable skin cancers. The favorable safety profile and high response rates are promising. A U.S. trial for marketing approval based on this pilot study is underway.”
Christopher A. Barker, MD, of Memorial Sloan Kettering Cancer Center, is the corresponding author for the JAMA Network Open article.
Disclosure: This study was supported by Alpha Tau Medical, which provided the study device and funding for the study, and by a grant from the National Cancer Institute. For full disclosures of the study authors, visit jamanetwork.com.
