Podcast Summary

Derms on Drugs – "What Actually Changes Practice (and What Doesn’t)"

Date: March 27, 2026
Hosts: Dr. Matt Zirwas (A), Dr. Laura Ferris (B), Dr. Tim Patton (C)
Theme:
An engaging roundtable where leading dermatologists dissect recent studies and developments, candidly exploring which new research actually shifts day-to-day clinical decisions, especially in melanoma diagnostics, bullous pemphigoid, urticaria, diaper rash remedies, hidradenitis suppurativa, atopic dermatitis, and even the safety of common neuropathic medications.

Key Discussion Points & Insights

1. Castle Biosciences 31-gene Expression Profile (GEP) Test for Melanoma

Segment: [01:38]–[16:29]

• Study Recap: Prospective study of 912 patients, trying to determine if GEP can reliably identify low-risk cutaneous melanoma patients to forego sentinel lymph node biopsies (SLNB).
• Findings:
  • Patients with <5% predicted risk by the test had a 1.8%–2.6% positivity rate on SLNB; those with >10% predicted risk had 16.7%–21.4% positivity.
  • For thicker tumors (T2B–T4), GEP did not distinguish risk as well (33% vs. 27% positive nodes in low- vs. high-risk groups), making the utility for thick melanomas questionable.
  • Recurrence-free survival did differ by risk group, but confounding by T stage was an issue.
• Takeaways:
  • Dr. Ferris: “Tumor thickness… still matters. I would not have the comfort level to say… no worries… even if you got a T4 melanoma, you’re good.” [08:29]
  • The GEP test may be useful for “hemming and hawing” T1B cases, but data is too generalized by T stage to change current practice.
  • Practice Impact: Consensus was the test is overused, and most patients opt for node biopsy regardless; guidelines and oncologist discussion remain key.

2. American vs. European Approaches to Bullous Pemphigoid (BP)

Segment: [17:47]–[27:43]

• US Expert Survey vs. European Guidelines:
  • US derms overwhelmingly choose systemic steroids over topical for mild-moderate and severe BP, contrary to some European recommendations.
  • Doxycycline widely preferred as a second-line agent; Rituximab underutilized in Europe compared to US opinions.
  • Notable Quotes:
    • Dr. Patton: “Nobody should be using topical steroids to treat like widespread BP. That European study… patients got hospitalized, they had nurses come in and apply clobetasol all over the body. Like, that just cannot be done realistically…” [18:11]
    • “If you’re treating severe BP with topical corticosteroids, don’t be treating severe BP. Refer those patients.” [19:57]
• Practice Tips:
  • Emphasized glacially slow steroid tapers for BP, especially when combining with dupilumab (DUPY).
  • Dr. Zirwas: “I think that’s the biggest mistake that people make is they’re like, okay, I got him on doopie. I can taper them in three weeks. No, you can’t. …Do it slow.” [25:07]

3. Novel Approaches to Diaper Rash

Segment: [27:43]–[30:23]

• Green Beans for Neonatal Diaper Rash: Adding pureed green beans to formula may help by increasing fiber and acidifying stool, reportedly reducing severe diaper rash in institutional settings.
• Humor & Takeaway: Quirky, but highlights practical creativity for common pediatric derm problems.

4. New Mechanisms and Agents in Urticaria

Segments: [30:23]–[41:44]

(A) Inducible Urticaria (Cold Urticaria)

• Dupilumab (DUPY): No benefit for chronic inducible urticaria (CIndU) in recent trials—works for chronic spontaneous urticaria (CSU), not “physical urticarias.”
  • Dr. Zirwas: “Dupilumab released their results and it does NOT work at all…literally nothing.” [31:53]
• Barzolivumab (Barzo): C-kit inhibitor, highly effective in cold urticaria; causes hypopigmentation and hair depigmentation.
  • “It just literally kills all your mast cells…makes your hair turn white.” [32:49]

(B) Dupilumab for CSU—Liberty CSU Cupid C Study ([35:41]–[40:55])

• Phase 3 data reaffirms that DUPY offers improved outcomes over placebo in antihistamine-refractory CSU (esp. in omalizumab-naïve patients):
  • ~43% achieved disease control compared to ~23% (placebo).
  • For omalizumab failures, DUPY much less effective.
  • Rapid onset of omalizumab makes it the go-to; DUPY seen as backup.

5. Cutting-edge/Curious Studies:

Segments: [41:44]–[47:13]

(A) Gamma Secretase Inhibitor Side Effects (Hydradenitis Suppurativa)

• Drug for desmoid tumors (neurogesestat) frequently caused follicular-based eruptions (including HS), possibly implicating Notch signaling/gamma secretase in HS pathogenesis.
  • “Maybe someday that'll be...I remember the Derms on Drugs people talking about that. They're visionaries." (C, [44:46])

(B) Melatonin for Atopic Dermatitis

• New Iranian RCT supports adjunctive melatonin (10mg QHS) improves AD severity (ScoreAD 31→11, BSA drop, symptom scores) beyond sleep alone.
  • Third RCT now shows benefit; mechanism possibly via skin and gut microbiome or cutaneous melatonin receptors.

(C) Gabapentinoid Use and Dementia Risk

• Taiwanese Population Study: Gabapentin/pregabalin use linked to increased risk of dementia (Hazard Ratio 1.5 overall; 3.16 under age 50).
  • Caution about overinterpretation—absolute risk in young is low and confounding by indication (e.g., pain, opioids, etc.).
  • Dr. Ferris: "Relative risk versus absolute risk. The absolute risk of dementia in somebody under 50 is very low. So even if you triple it, who cares?" [52:45]

Notable Quotes & Memorable Moments

• On the overuse of the GEP test:
  Dr. Patton: “I think Castle is way, way overordered. …But is anyone going to do that? …Don't go to the airport…” [12:45]
• BP pearls:
  Dr. Ferris: “The thing I’ve learned most from Tim over the years is…use some doxy, but taper [prednisone] really slowly.” [25:30]
• Practical research skepticism:
  Dr. Zirwas: "As you can guess, back of the envelope math is really the only kind that I do." [09:36]
• Humorous skepticism on patient volume:
  Dr. Patton: “…one of the respondents said that they see 120 BP patients a month. Like, no, you do not. Get out of here with that.” [24:30]
• On diaper rash advice:
  Dr. Patton: "I like any paper where Matt can say the word poop, like, seven to ten times. That really brings the discourse to a level that I think people expect from this podcast. Bravo, Matt." [29:29]

Important Segment Timestamps

| Timestamp | Topic | |-----------|-------------------------------------------------------| | 01:38 | Castle GEP Melanoma Study discussion starts | | 11:34 | Tumor thickness, GEP test limitations | | 17:47 | Bullous pemphigoid: US vs EU guidelines | | 25:30 | Practical BP prednisone tapering advice | | 27:43 | Green beans for diaper rash tip | | 30:23 | Chronic inducible urticaria: Dupilumab, Barzolivumab | | 35:41 | Liberty CSU Cupid C dupilumab trial in CSU | | 41:44 | Gamma secretase inhibitors and hidradenitis suppurativa| | 47:13 | Melatonin for atopic dermatitis RCT | | 51:21 | Gabapentin/pregabalin and dementia risk | | 52:45 | Risk analysis, relative vs. absolute, Shingrix digression|

Overall Tone:

The conversation is energetic, skeptical, and humorous, with regular use of clinical slang and laid-back banter, plus moments of self-deprecating honesty ("back of the envelope math," "I'm committed to this paper, I don't do that"). The hosts balance real clinical skepticism with an enthusiasm for new findings, while poking fun at themselves and each other.

Practice-Changing Pearls

• Castle GEP not ready to replace clinical judgment or guidelines for SLNB in melanoma—especially not for thick tumors.
• In the US, systemic steroids firmly remain first-line for BP, and topical steroids alone are impractical. Rituximab earlier, very slow prednisone tapers, and consider doxy early.
• Dupilumab is highly effective for CSU but not inducible urticaria; omalizumab remains preferred first add-on.
• Novel therapies for urticaria (Barzolivumab, Remibrutinib) show promise, but with unique side effects (e.g., depigmentation).
• Melatonin appears to help atopic dermatitis somewhat independently of sleep improvement.
• Gabapentinoids may elevate dementia risk—especially in young—warranting more cautious use and careful risk-benefit analysis.

This episode is a must-listen for anyone navigating the intersection of emerging derm literature and everyday clinical reality—with plenty of laughs and practical gems from three experienced, opinionated voices.