Diagnosing And Treating A Longstanding Heel Lesion
Dr. Markinson takes a slightly different tack on porokeratoses. “I have biopsied them many times in 25 years and I seem to have gotten back whatever diagnosis I submitted,” he says. “That would include the diagnosis of ‘wart’ when no typical clinical findings existed. Therefore, I have come to believe that early warts may be clinically similar to the porokeratotic lesion.”2
Another well respected dermatology thought leader, Dr. Dockery, weighed in with the following provocative statement and I have come to believe this as well.
“I am not absolutely sure that there is a true entity as the ‘porokeratosis plantaris discreta’ but I do believe there are painful keratotic lesions that form on the foot that are relatively resistant to palliative treatments,” notes Dr. Dockery. “For these lesions, I recommend the sublesional injection of 4% diluted alcohol solution. This will stop the nerve pain and resolve the keratotic lesion in most cases.”3
A Comprehensive Guide To Treatment
Debridement still remains the key principle of treatment for both IPK and porokeratosis. What one does beyond that determines whether the patient must return at the two-month point or is able to delay that return until the four- to six-month point.
On the eTalk blog accessible through www.Podiatry.com, when you search “porokeratosis,” you will find that there have been at least 47,115 views of this thread since my friend and former University of Texas Health Science Center faculty member John Steinberg, DPM, simply asked if anyone had any ideas for the treatment of porokeratoses in May 2009.4 The lesion was first named by his grandfather, Marvin Steinberg, DPM, the “Father of Podiatry.”
You always know there is not a perfect answer for a treatment when so many suggestions are offered. Dermatology experts believe preparation of the remaining tissue after debridement is essential to long-term success.
Cryotherapy, such as that offered by the Cryoprobe™ (H&O Equipments) and delivered to the conical tissues that remain after debridement, seems to greatly delay the return of the lesion. Another popular treatment that offers a similar outcome is the placement of cantharidin (Canthacur, Paladin Laboratories), the medication developed from the blister beetle. It has been difficult to obtain at times over the past years. It was popularized some years ago as a treatment for verruca.
Both treatments produce an inflammatory reaction. Experts with whom I have spoken liken this to an immune reaction. This reaction, produced by the patient’s own body, is not yet understood completely but somehow delays the return of the lesion more than the solitary debridement technique.
A third treatment — the sublesional injection of 4% diluted alcohol solution proposed by Dr. Dockery — denies the lesion of its nerve supply. This results in subsequent deterioration of the lesion. This treatment may also speak to the fact that on occasion, after surgical treatment, I have found an associated neuroma beneath the dermatologic lesion.
There is a need for research on this old problem that still worries us and causes pain for our patients. However, we first need to settle on a name that fits this lesion. It is not a true porokeratosis like those associated with bronchial and squamous cell carcinoma or autosomal dominant polycystic kidney disease. To call the keratinized lesion we treat in the foot a “porokeratosis” is a true misnomer.
Dr. Satterfield is a Fellow and President-Elect of the American College of Foot and Ankle Orthopedics and Medicine. She is board certified in foot and ankle orthopedics and medicine. Dr. Satterfield is Director of the Pre-Clinical Curriculum and an Associate Professor at the Western University College of Podiatric Medicine in Pomona, Calif. She recently received the Master’s distinction from the American Professional Wound Care Association.