Image-guided superficial radiation as first-line in skin cancer?

The study covered in this summary was published on medRxiv.org as a preprint and has not yet been peer reviewed.

Key takeaway

• Absolute lesion control rate with image-guided superficial radiation therapy (IGSRT) for early-stage nonmelanoma skin cancer was achieved in nearly all patients.

Why this matters

• IGSRT is a newer radiation technique for skin cancer, an alternative to Mohs micrographic surgery and other surgical options.
• The ultrasound imaging used during IGSRT allows for precise targeting of cancer cells while sparing surrounding tissue.
• IGSRT is currently recommended for early-stage nonmelanoma skin cancer among patients who refuse or cannot tolerate surgery.
• Given the safety, lack of surgical disfigurement, cost-effectiveness, and high cure rate, IGSRT should be considered more broadly as a first-line option for early-stage nonmelanoma skin cancer, the researchers concluded.

Study design

• The investigators reviewed 1,899 early-stage nonmelanoma skin cancer lesions in 1,243 patients treated with IGSRT at an outpatient dermatology clinic in Dallas.
• Energies ranged from 50 to 100 kV, with a mean treatment dose of 5,364.4 cGy over an average of 20.2 fractions.
• Treatment duration was a mean of 7.5 weeks and followed for a mean of 65.5 weeks.

Key results

• Absolute lesion control was achieved in 99.7% of patients, with a stable control rate of 99.6% past 12 months.
• At a 5-year follow-up, local control was 99.4%.
• Local control for both basal and squamous cell carcinoma at 5 years was 99%; local control for squamous cell carcinoma in situ was 100% at 5 years.
• The most common side effects were erythema, dryness, and dry desquamation. Some patients had ulceration and moist desquamation, but it did not affect lesion control.
• The procedure was well tolerated, with a grade 1 Radiation Treatment Oncology Group toxicity score in 72% of lesions.
• The results compare favorably with Mohs surgery.

Limitations

• No study limitations were noted.

Disclosures

• No funding source was reported.
• Senior investigator Lio Yu, MD, reported research, speaking and/or consulting for SkinCure Oncology, a developer of IGSRT technology.

This is a summary of a preprint research study, “Analysis of Image-Guided Superficial Radiation Therapy (IGSRT) on the Treatment of Early Stage Non-Melanoma Skin Cancer (NMSC) in the Outpatient Dermatology Setting,” led by Alison Tran, MD, of Baylor University Medical Center, Dallas. The study has not been peer reviewed. The full text can be found at medRxiv.org.

A version of this article first appeared on Medscape.com.