Alternative treatment for recurrent keloids: initial clinical experience with Rhenium-188 using a specialized device

Abstract

Introduction

Keloids have proved challenging to manage with various therapies providing variable success rates and recurrences. Alternative therapies or a multimodal approach is often necessary to ensure complete eradication and prevent recurrence. The use of radioactive creams or patches embedded with Holmium-166, Phosphorus-32 for superficial skin lesions has been documented to be safe and effective. The use of Rhenium-188 has proved effective in non-melanoma skin cancers. We report on the initial experience with Rhenium-188 SCT in the treatment of recurrent keloid lesions.

Methods

Patients with recurrent keloid lesions were recruited for therapy with Rhenium-188. These patients had failed most forms of therapy including surgery, intralesional steroids and radiation therapy. Treatment with ¹⁸⁸Re via a specialized unit (Rhenium SCT -Oncobeta) was applied onto the keloid lesion. A personalized treatment time was calculated for every patient. Topical ¹⁸⁸Rhenium delivered as a jelly like matrix containing an insoluble dirhenium-heptasulfide was applied to every target lesion in a single session. The goal is to deliver 30 Gy to the deepest part of the lesion per session (3 mm). Patients were followed up at 2 weeks, 1, 3, 6 and 12 months for side effects as well as clinical and cosmetic outcomes.

Results

A total of 58 lesions were treated. Majority of the lesions were in the head and neck region. The smallest area for treatment was 0.25cm² and the largest area treated was 46.25cm². With the exception of four patients (2 sessions to the same lesion), all the other patients received a single session of therapy. The mean activity administered was 256,7MBq (range: 35MBq– 663,50MBq). The treatment time averaged 350.89 min (range: 85–1304 min). There was complete response in 72% of the lesions. Hypopigmentation was the commonest expected long term side effect. After a median follow-up period of 37 months (range: 7–53), there was a 7% recurrence rate.

Conclusion

Treatment with ¹⁸⁸Re is a great alternative in patients with keloids that have had minimal success with other therapies. The use of the specialized applicator system provides great flexibility, reduced morbidity and great results that are comparable to other therapies.

Clinical trial number

Not applicable.