Derms on Drugs – Episode Summary

Episode: Melanoma, EMPD, and a Prostate Drug Walk Into a Bar...
Date: March 13, 2026
Hosts: Dr. Matt Zirwas, Dr. Laura Ferris, Dr. Tim Patton

Episode Overview

This episode of Derms on Drugs dives into recent advances and controversies in dermatologic oncology and therapeutics, with the typical blend of camaraderie and off-beat humor. The panel covers new studies on gene expression profiling in early melanoma, multidisciplinary management of extramammary Paget disease (EMPD), and a surprising contender in the management of female pattern hair loss. The dynamic between the hosts keeps the episode lively while maintaining a high-yield, practical focus for clinicians.

Main Discussion Points & Insights

1. Gene Expression Profiling (GEP) in Early Melanoma

[02:35–23:53]

T1A Melanoma and DecisionDX 31-GEP

• Study discussed: Joshi et al., two reports from JAD using SEER database.

• Key criteria:

  • Low vs. high clinical risk T1A, defined by age (>42), Breslow (<0.5mm), mitotic rate, and location.
  • Vast majority (>90%) of T1As, both low and high clinical risk, were class 1A (low risk) per 31-GEP.
  • “This kind of fits with other data...pretty much if you’re going to send T1As, the vast majority ... come back as low risk.” – Dr. Ferris [06:45]

• Crucial insight: The 31-GEP test may offer little added value for T1A cases, as it rarely alters management or prognostication.

• Notable teaching moment: Discussion on age as a risk:

  • Older patients are less likely to have sentinel node positivity but more likely to die from melanoma, likely due to declining lymphatic integrity and immunity. [09:09–11:01]

  • “Older age, lower likelihood of having a sentinel node that's positive, but higher risk of death.” – Dr. Ferris [09:55]

  • “The thought is…your lymphatics—like everything else as you get older—don’t work as well.” – Dr. Ferris [10:01]

T1B Melanoma and GEP Utility

• T1B: Anxious zone (“discuss and consider” SNB per NCCN)
• 57% of patients underwent SNB, with 11.5% positive; 82% of positive nodes were in “low risk” (class 1) GEPs.
• Absence of clear correlation between higher GEP risk and poor outcome without SNB.
• “The authors concluded their data do not support using 31-GEP to omit sentinel node in T1B.” – Dr. Ferris [15:55]

Pragmatic Takeaways & Critique

• “Castle testing is rammed down our throats…most oncologists and surgeons absolutely ignore Castle stuff because they’re like, look, I have seen bad melanomas that were 1A. It’s not a reliable test in their hands.” – Dr. Patton [16:35]
• Multidisciplinary decision-making is essential; GEP should only be used if it will clearly affect the management plan.

Cost Analysis

• GEP ($7,193) is often pricier than SNB ($3,470–$6,220).
• “Both their sentinel node numbers are less expensive than the GEP test.” – Dr. Ferris [19:14]

Real-world Recommendations

• Order GEP only if results will directly change management (e.g., elderly with comorbidities, surgical risk; not for all-comers).
• “It is going to change what I am going to do… If we get this result, we’re going to make this decision; with this one, we’ll make a different decision.” – Dr. Ferris [20:36]
• NCCN guidelines remain the hosts' “North Star” for melanoma management, regularly updated and free to access. [23:53–25:15]

2. Extramammary Paget Disease (EMPD): Mohs + Adjuvant Radiation

[26:26–36:28]

EMPD Clinical Background [27:00]

• Rare epithelial malignancy in apocrine-rich sites (vulva, penis, scrotum, occasionally axilla).
• Workup: CK7+, CEA+, Sox10–, sometimes CK20+. Screening for underlying adenocarcinoma (especially colorectal, bladder, prostate, breast is less clear).

Study Review: Mohs Plus Radiation

• Zhang et al, Postgrad Med J 2026 (Peking University): Retrospective review of 87 patients undergoing Mohs surgery plus adjuvant radiotherapy.
• 5-year local recurrence: 3.3% (improvement over previous rates).
  • Previous recurrence: WLE 26.7%, Mohs alone 7.3%.
  • Most patients men, tumors perineal; some (rare) axillary.
• Acute skin toxicity in some, but only 6/87 discontinued therapy.
• “Not unreasonable to strongly consider adjuvant radiation therapy... If you took it from 7.3 down to 3, not unreasonable to consider.” – Dr. Patton [33:25]

New Diagnostic Algorithm (2025)

• Immunostain panel adds TRPS1: TRPS1+ is highly specific for primary EMPD.
• If TRPS1–, use additional stains (CK20, CDX2, SATB2, P63, GATA-3, etc.) to distinguish secondary involvement (e.g., colon, urothelial, or prostatic).
• “If you are TRPS1 positive, that is primary EMPD. Like, that's it, done.” – Dr. Patton [34:44]
• Visual diagram suggested for board review and practical workup.

3. Bicalutamide vs Spironolactone in Female Pattern Hair Loss

[36:28–42:10]

Clinical Trial Review

• China: RCT, bicalutamide (50mg) vs. spironolactone (100mg) in 204 women (188 completed), 24 weeks.
• Bicalutamide = superior:
  • Nearly double improvement in hair density and shaft diameter by trichoscopy.
  • No visible difference in photos at 6 months, but hosts note longer follow-up is likely needed.

Safety and Practicalities

• Bicalutamide: Generally safe, lower AE rate than spironolactone.
  • Main risk: rare but monitorable LFT abnormalities; baseline and periodic monitoring recommended.
• Recall: not for women of childbearing potential (like finasteride); caution as per Accutane standards.
• Developed for metastatic prostate cancer, but “very cheap, very safe” in derm context.
• Clinical caveat: still waiting for photographically/everyday visible outcome data.
• “We need the true clinical outcome data—none of us are treating our trichoscopic findings; we're treating…does my hair look thinner or not?” – Dr. Ferris [41:35]

4. Medication-Induced Pruritus in Diabetic Renal Disease

[42:21–45:19]

• Review of a cross-sectional study in chronic renal failure/dialysis patients with chronic pruritus.
• Drugs associated with increased pruritus:
  • Alpha glucosidase inhibitors
  • Dipeptidyl peptidase-4 inhibitors (30% increased risk)
  • Statins (40% increased risk)
  • Additive effect with multiple drugs.
• Mechanistic context: Statins reduce cholesterol production in skin, leading to dryness; DPP-4 inhibitors already linked to pemphigoid.
• Clinical teaching: Spongiosis in a rash rarely means drug reaction—interfacial/lichenoid/plus eosinophilia patterns are more classic.
  • “I am a firm believer that we way over diagnose drug rashes…spongiosis is incredibly unlikely to be a drug rash.” – Dr. Zirwas [44:06]

Notable Quotes & Segment Highlights

• [10:01] Dr. Ferris:
  “Lymphatics get leakier the older that we get... like you've got bad pipes getting you to the lymph node.”

• [16:35] Dr. Patton:
  “Castle testing is rammed down our throats…most oncologists and surgeons absolutely ignore Castle stuff because they’re like, look, I have seen bad melanomas that were 1A.”

• [20:36] Dr. Ferris:
  “For me, [GEP] is one, it is going to change what I am going to do… If we get this result, we're going to make this decision; with this one, we’ll make a different decision.”

• [23:53] Dr. Zirwas:
  “The Derms on Drugs are big supporters of the NCCN guidelines... your North Star, and they are updated.”

• [34:44] Dr. Patton:
  “If you are TRPS1 positive, that is primary EMPD. Like, that's it, done. You're done.”

• [41:35] Dr. Ferris:
  “We need the true clinical outcome data—none of us are treating our trichoscopic findings; we're treating…does my hair look thinner or not?”

Segment Timestamps

• [02:35–23:53] Melanoma gene expression profiling (DecisionDX 31-GEP)
• [26:26–36:28] EMPD: Mohs surgery + adjuvant radiation & new diagnostic algorithm
• [36:28–42:10] Bicalutamide vs. Spironolactone in Female Pattern Hair Loss
• [42:21–45:19] Medication-induced pruritus in diabetic chronic renal failure
• [Throughout] Witty banter, clinical cases, and practical reminders

Episode Takeaways

• Gene expression profiling tests should be ordered thoughtfully, with real expected impact on management—avoid indiscriminate use.
• Adjuvant radiation appears promising for EMPD post-Mohs in select patients.
• Bicalutamide is emerging as a superior (and safe) alternative to spironolactone in female pattern hair loss—pending longer-term data.
• Statins and DPP-4 inhibitors can contribute to pruritus, especially relevant in elderly/diabetic/renal patients.
• NCCN guidelines remain the panel’s foundation for current oncologic dermatology practice.

Clinical Pearls

• Check with your oncologic/surgical colleagues before ordering GEP—know your institution’s practices.
• Consider adjuvant radiation for high-risk/surgically challenging EMPD, and use updated IHC staining protocols for diagnosis.
• For medication-induced itch, statins and DPP-4 inhibitors are culprits; but think carefully before blaming medications for nonspecific rashes.
• When new therapies (like bicalutamide) emerge, look for photographic data and everyday practical effect—not just trichoscopic improvement.

Closing Thoughts

The hosts keep a light tone while sharing in-depth clinical insights, practical data interpretation, and frequent reminders to use evidence-based guidelines. The interplay between the panel provides both learning and entertainment—a hallmark of the “Derms on Drugs” style.