A unique device, CellFX, is currently under investigation for the treatment of benign skin lesions and some nonmelanoma skin cancers. At the ODAC Dermatology, Aesthetic and Surgical Conference, held in Orlando, FL, Edward Ross, MD, presented the latest evidence on the use of high amplitude electromagnetic fields for treating warts and other dermatologic conditions, as well as the role this device will play in dermatology.
Dr Ross is the director of the Scripps Clinic Laser and Cosmetic Dermatology Center in San Diego, CA. He is also an investigator for Pulse Bioscience, which developed Nano-pulse stimulation technology and CellFX.
The Dermatologist: What are the mechanisms of action of the Nano-pulse stimulation technology and CellFX, and how is it unique compared with other devices in dermatology?
Dr Ross: Nano-pulse stimulation technology, delivered through CellFX, are completely different compared with other electric and energy-based devices used in dermatology. It has a cell-specific effect. The device produces non-thermal, ultra-short, high-amplitude electric pulses, which cause regulated cell death in the treated lesion, but do not affect the background skin.
The electric current is delivered to the lesion through the tip, which has what looks like little pins that protrude about 2mm. There are several different sized tips for different sized lesions, ranging from 1.5 to 10 mm. In our study of non-genital warts, we usually used the 5 mm long tip.
The theory, which has been supported by the evidence, is that the shocks from this device damage the cell and start the process of regulated cell death, or apoptosis. What is interesting about this is that the shocks only damage the cells, and parts of the skin that are not cellular, such as collagen, seem to be spared. In other words, things that have a lot of cells tend to respond better than the background skin.
In addition, there is a possible immunogenic response as well, which is still being investigated. It appears that after the stress to the cells caused by the electrical pulses, the shock promotes antigen presentation, as well as the incitement of tumor antigen‑specific T cells. For example, in basal cell carcinoma, and perhaps even melanoma, there may be a stimulatory immunogenic phenomenon going on beyond the death of the cell.
The Dermatologist: How does this device administer electric pulses?
Dr Ross: The device delivers electric pulses through the pins, which are inserted into the lesion, for about 20 to 30 seconds, with about 3 to 4 shocks per second, and stops after the full complement of pulses has been administered. If the wart responds to treatment, it usually turns black and falls off. During our studies on warts, we also used an injectable anesthetic because this procedure is a bit painful.
The Dermatologist: What conditions would best be treated with this device? How effective is this device, and what are some ongoing trials?
Dr Ross: The list of lesions we could use this for in dermatology is fairly long, because anything that is cellular in nature would be vulnerable to this device and therefore would be treatable. Currently, there are ongoing studies for sebaceous hyperplasia, seborrheic keratosis, basal cell carcinoma, and warts, which are what I studied. Future studies will focus on syringomas, adnexal tumors, acne, and congenital melanocytic nevi, among others.
The initial research has been positive, with very good response rates. In warts, we have seen about 60% to 70% clearance, and there have been higher clearances reported for sebaceous hyperplasia, which have been above 90%.
In the studies I have done, we treated over 20 patients with warts. The majority of these patients received approximately 2 treatments about a month apart. Our new trial will investigate this device on warts using up to 4 or 5 treatments. We were initially hopeful CellFX would only require 1 treatment, but we realize now it may take anywhere from 2 to 5 treatments, which is common for most therapeutic options for warts.
We have found the majority of warts respond about 90% to 100% of the time after 2 treatments. However, there is a small subset of patients (less than 20%) with warts that are persistent and do not respond to treatment.
Another interesting phenomenon we observed is that some warts not located in the immediate treatment field “spontaneously” resolve a month or 2 after treatment. For example, a wart about 2 or 3 cm away from the original treatment site on the foot will also disappear. However, this is not seen every time.
The Dermatologist: What adverse effects have been observed so far?
Dr Ross: The good news about this device is adverse effects have been few and far between. The main ones we have seen are temporary hyperpigmentation and discomfort during the procedure. However, pigmentary changes resolve over time. Early on, there were a few small scars following treatment of seborrheic keratoses, but most of these resolved over time and have not been observed since.
One of the things we have learned is that less is more as far as the amount of energy per pulse. In response to this, the company’s philosophy, particularly for smaller lesions, has been to decrease the amount of energy per pulse and increase the benefit-to-risk ratio. There are already very few risks associated with use of this device to begin with, but the goal is to lower these risks even more.
Ross, V. High amplitude electromagnetic fields-a new player in dermatology. Presented at: ODAC Dermatology, Aesthetic and Surgical Conference; Orlando, FL; January 17, 2020.