A new type of radiotherapy may be better than surgery for patients with early-stage nonmelanoma skin cancers

A new type of radiotherapy may be better than surgery for patients with early-stage nonmelanoma skin cancers

October 4, 2021

In a recent study, image-guided superficial radiotherapy (IGSRT) showed nearly a 100% cure rate for early-stage basal cell carcinomas and squamous cell skin cancers. These results, along with its established safety, show that IGSRT is emerging as an alternative to cryosurgery or Mohs micrographic surgery (MMS), which are commonly used to treat many non-melanoma skin cancers.

Radiotherapy, also called radiation therapy, is a cancer treatment that uses high doses of radiation to kill cancer cells and shrink tumors. Superficial radiation therapy (SRT) without imaging capabilities has been used previously to treat skin cancer, with low rates of complications and favorable cosmetic results similar to MMS. However, studies showed that this treatment method had lower rates of overall cure compared with MMS, and the use of SRT has decreased over the years. Image-guided superficial radiotherapy (IGSRT) is a newer type of radiotherapy that uses ultrasound imaging to target the radiation to the cancer more precisely than older methods.  Now, with the inclusion of high-frequency ultrasound imaging with SRT, providers are able to more accurately estimate the dimensions of the tumor. This allows them to estimate radiation doses and choose the energy settings for the device more precisely to match the specific tumor depth and type.

IGSRT represents a viable nonsurgical treatment option that may be appealing to many patients who are unable to or choose not to undergo surgery. It offers a reduction in risk of pain, scarring, and infection or bleeding associated with surgery. IGSRT also avoids the suturing and anesthesia required for MMS. A study of the efficacy and safety of IGSRT found that the technique was successful in treating a range of tumor types and sizes, including those that were considered high-risk lesions.  However, some limitations to IGSRT include that it cannot be used to treat tumors deeper than 6 mm and that the ultrasound imaging is difficult to attain if the skin cancer surface is irregular or bleeding actively.

Given that basal cell carcinomas and squamous cell skin cancers are often found on the head and neck, one attractive feature of IGSRT technology is its ability to reduce the cosmetic impact. Thanks to the technique’s improved accuracy in targeting the cancer cells and dosing when compared with other forms of radiation therapy, IGSRT reduces the damage to surrounding healthy tissue.

Although studies analyzing the use of IGSRT are ongoing, it has become increasingly popular among dermatologists across the United States. According to study co-author and dermatologist Christopher R. Shea, MD, from the University of Chicago: “The results of this study demonstrate that IGSRT should be considered as a first-line treatment option for early-stage basal cell and [cutaneous] squamous cell carcinoma.”

References

The science behind IG-SRT | Image-guided superficial radiotherapy. New York, NY: SkinCure Oncology; September 8, 2021. https://www.skincureoncology.com/clinical-model/the-science-behind-ig-srt/. Accessed September 23, 2021

Slocum L. Image-guided superficial radiotherapy for BCC and SCC. Dermatology Times. September 15, 2021. https://www.dermatologytimes.com/view/image-guided-superficial-radiotherapy-for-bcc-and-scc. Accessed September 23, 2021.

Study shows image-guided superficial radiotherapy Is 99.3 percent effective in treating common skin cancers without surgery (news release). New York, NY: SkinCure Oncology; September 8, 2021. https://www.prnewswire.com/news-releases/study-shows-image-guided-superficial-radiotherapy-is-99-3-percent-effective-in-treating-common-skin-cancers-without-surgery-301371628.html. Accessed September 23, 2021.

Yu L, Oh C, Shea CR. The treatment of non-melanoma skin cancer with image-guided superficial radiation therapy: an analysis of 2917 invasive and in situ keratinocytic carcinoma lesions. Oncol Ther. 2021;9: 153–166. https://doi.org/10.1007/s40487-021-00138-4