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case report Archives | ODAC Dermatology, Aesthetic and Surgical Conference

New and Emerging Therapies for Advanced Non-Melanoma Skin Cancer

By | Medical Dermatology, ODAC Sessions | No Comments
Advanced non-melanoma skin cancer patient image

Source: Next Steps in Dermatology 

At the 17th Annual ODAC Dermatology, Aesthetic, and Surgical Conference (ODAC) held January 17-20 in Orlando, FL, Dr. Desiree Ratner led a discussion on new and emerging therapies for advanced non-melanoma skin cancer discussion.

Treatment Options
The session covered several treatments for patients including patidegib gel 2% and 4% applied once or twice daily in patients with basal cell carcinoma. Patidegib is a topical hedgehog inhibitor made by PellePharm and its mechanism of action is to block Smo signaling, thereby inhibiting the hedgehog pathway that contributes to the development of basal cell carcinomas. This treatment has several advantages in that it does not contribute to hair loss, taste loss, or muscle cramps. It has the potential to treat and mitigate facial basal cell carcinomas in basal cell nevus patients. It is being studied in randomized clinical trials enrolling patients with Gorlin’s syndrome (basal cell nevus syndrome) in the United States and in Europe.

Hedgehog pathway inhibitor resistance is unusual but may occur as “rebound” tumor growth after drug cessation or secondarily after long-term smoothened inhibitor therapy. Resistance to hedgehog pathway inhibitors is classified into primary and secondary resistance. Primary resistance has been postulated to bypass mechanisms of genes downstream of smoothened, such as the G497 W mutation. Secondary resistance in patients who showed an initial response has actually been thought to be due to de novo mutations located on regions in smoothened to which hedgehog pathway inhibitors bind or selective clonal expansion of minority clones in the pre-treated tumor. Further studies are definitely needed to elucidate what drives resistance to hedgehog pathway inhibitors and how basal cell carcinoma resistance may be overcome by other novel, emerging therapies.

Patient Cases
Dr. Ratner presented a number of interesting patient cases with advanced basal cell carcinomas sometimes so large that patients lose mobility and function of a body part or organ. In most cases, locally advanced BCCs respond well to oral hedgehog inhibitors, which can be used for long-term control or neoadjuvantly prior to surgery. In the case of one patient, an aggressive orbital BCC caused contraction of the tissues around his eye, such that he was not able to open it. Despite treatment with an oral hedgehog inhibitor, his tumor continued to grow, resulting in destruction of his orbit and locoregional metastasis.

Samples of his tumor and normal skin were sent to Stanford University, which performed whole exome sequencing. In the studies of these samples, it became evident that the tumor should have responded to vismodegib but had developed resistance due to another as yet unknown mechanism. Therapies designed to override resistance such as second-generation smoothened inhibitors are under development.

Read more. 

Fungus Among US: Practical Case-Based Dermatophytosis

By | Medical Dermatology, ODAC Sessions | No Comments
Patient with fungus on foot

Source: Next Steps in Derm

This information was presented by Dr. Adam Friedman at the 16th Annual ODAC Dermatology, Aesthetics and Surgical Conference held January 18th-21st, 2019 in Orlando, FL.

Dermatophytosis constitutes a big chunk of “bread and butter” in dermatology.  In fact, an average of 4.1 million visits a year were due to dermatophytosis from 1995 to 2004! Nevertheless, these fungi can still stump the most seasoned dermatologist, and misdiagnosis can be surprisingly common. Dr. Adam Friedman, Professor, Interim Chair, and Program Director of Dermatology at George Washington School of Medicine and Health Sciences, recently presented interesting cases and practical pearls on how to diagnose and treat dermatophytosis. Here are some highlights.

Make the Diagnosis

Here’s the golden rule: if there is scale, scrape it! KOH preparation is first line in diagnosis of dermatophytosis.  Do you follow this rule? A recent survey showed that the percentages of dermatologists who scrape when suspicious of dermatophytosis were only 20-30% (always) and 30-40% (very often). Next, histology can be helpful in diagnosing nail fungus and Majocci’s granuloma (where KOH is usually negative).  Fungal culture be helpful to guide anti-fungal therapy, especially for tinea capitis in children. 

Tinea Pedis

Tinea pedis is the most common form of skin fungal infection, and there are 4 types: moccasin, interdigital, bullous, and ulcerative.

Don’t forget that non-dermatophytes (S. dimidiatum; S. hyalinum) can cause identical findings!  Also, an exuberant dermatophytid (or “id”) reaction, an inflammatory response to the fungal infection, can accompany findings of dermatophytosis. When you see a 2-hand-1-foot (or vice-versa) involvement, this can be another clue for diagnosing tinea pedis.

While topical azoles (econazole, other azoles) and allylamines (terbinafine, naftifine) and antifungal powder/spray weekly to shoes have been the mainstay treatment, there are some new topical options available.  Luliconazole 1% cream (daily for 2 week) for moist macerated web space; naftifine 2% gel and cream (daily for 2 week) for dry, scaling plaques; and urea 40% cream for moccasin tinea pedis have shown efficacy.

What about systemic anti-fungal therapy? The moccasin type and vesicular type may warrant oral terbinafine 250mg BID for 2-6 weeks and 2 weeks, respectively.  Since the vesicular type may have superimposed bacterial infection, an oral antibiotic may also be considered.

For more Tinea, click here.