Reemergence of targeted photon therapy useful for NMSCs in outpatient setting

Miami Beach, Fla. - Recent advances in radiation therapy for the treatment of nonmelanoma skin cancer (NMSC) have resulted in a resurgence of targeted photon therapy, a treatment modality particularly useful in an outpatient setting. In carefully selected patients and cases, radiation therapy can often be the treatment of choice for NMSCs, says a clinician who spoke at the annual meeting of the American Academy of Dermatology.

“Radiation therapy and the updated targeted photon therapy technology and protocols allow us to treat nonmelanoma skin cancers in those patients who are considered suboptimal candidates for surgical procedures,” says David E. Kent, M.D., division of dermatology, department of internal medicine, Mercer University School of Medicine, Macon, Ga. “The improved therapeutic modality gives us a lot of flexibility and versatility in the treatment and management of nonmelanoma skin cancers.”

Before the advent of Mohs surgery and larger surgical excision techniques using sophisticated flaps and grafts, radiation therapy was a very commonly used therapeutic tool for the treatment of NMSCs. Over the years, however, dermatologic surgeons gravitated toward using these newer surgical techniques, Dr. Kent says, as they were also effective in treating lesions.

Radiation therapy was always considered to be an effective treatment modality for NMSCs, but Dr. Kent says its use by dermatologists in an outpatient setting was limited by outdated technology and treatment protocols, which was further overshadowed by newer and exciting treatments and techniques such as Mohs micrographic surgery.

Targeted photon therapy

“Until recently, all the old radiation therapy technology was 30 to 40 years old, without the production of newer machines or any new research and development performed. The quality of the older machines became somewhat dated and devices became temperamental, requiring effort to perform radiation treatments,” Dr. Kent says.

The status quo has changed with the development of newer more efficient radiation machines that are safer than the technology of old, equipped with standardized double and triple safety features.

“What’s really wonderful about targeted photon therapy is that the dosimetry or the scheduling of the doses is now made so much easier with total fraction tables. Missed doses can now be quickly recalculated to ensure that the patient receives the appropriate updated dose for their tumor,” Dr. Kent says.

There is a fundamental difference between the electron-based ionizing radiation of linear accelerators used in hospital-based radiation centers, Dr. Kent says, and the photon devices used in a dermatologist’s practice. Devices now used in an outpatient setting in private practice deliver targeted photon radiation therapy, which is better suited for treating superficial NMSCs, he says.

Device improvements

The new photon devices are easier to use, emit less radiation than dental X-rays, and undergo yearly rigorous state inspections by the departments of health, according to Dr. Kent.

“With the advent of modernized and improved radiation technology in the machines that are now available, this treatment approach is being revalued and reconsidered once again as a viable treatment option in select patients and cases,” Dr. Kent says.

Patient selection is crucial, he says. Ideal candidates for radiation therapy are those individuals who are of advanced age, have multiple skin lesions and/or lesions in critical areas, are more aesthetically inclined and prefer a non-scarring treatment option, are afraid of surgery, or are contraindicated for surgical interventions due to standing comorbidities.

“One of the benefits of radiation therapy is that we can concurrently treat multiple lesions in one sitting. This can be a great advantage in much older patients who not only do not have to endure multiple surgeries to address their lesions, but they also can have all of their lesions treated in one sitting, quickly and painlessly. Depending on the case, therapy may take a series of treatments, and the number of treatments can be coordinated and individualized to the specific patient and case,” Dr. Kent said.

The most common locations where radiation therapy is used for NMSCs are the face, head and neck. While radiation therapy should be reserved for primary NMSCs, Dr. Kent says the therapeutic modality should not be used in those tumors that have aggressive histologic growth features such as often seen in morpheaform basal cell carcinoma. For more invasive and aggressive tumors, he says Mohs surgery may often be the better treatment option.

“For select patients and tumors, targeted photon therapy is an excellent option to consider. In my experience, the new and improved radiation therapy technology offers us a viable, cost-effective and cosmetically attractive treatment option for nonmelanoma skin cancers and is a wonderful addition in our armamentarium,” Dr. Kent says.

Disclosures: Dr. Kent reports no relevant financial interests.