Welcome back to the journal review. This is the February twenty twenty-six issue of the Journal of the American Academy of Dermatology, and we've got four pieces worth your time today — a clinical differences study on nail pigmentation, a full clinical practice guideline for basal cell carcinoma in Gorlin syndrome, and two JAAD Game Changer retrospectives worth revisiting for how they've actually shifted counseling and follow-up. Let's get into it.

First up is an original retrospective study out of Kyungpook National University in Korea, looking at how to clinically distinguish true Hutchinson's sign in subungual melanoma from pseudo-Hutchinson's sign in benign longitudinal melanonychia. You already know the clinical problem here better than most — periungual pigmentation visible through the nail fold is one of those findings that triggers a biopsy reflex, but a meaningful chunk of it is just pigment shining through translucent nail fold tissue rather than true epithelial melanocytic extension. The gap the authors are targeting is that nobody had rigorously catalogued which morphologic features actually separate the real sign from the mimic.

Methodologically, this is a single-center retrospective chart and photo review, and it's a reasonable design choice given the question — you're not testing an intervention, you're trying to characterize morphology across a reasonably large cohort of a rare-ish tumor, and retrospective review lets you accumulate the numbers you need. They pulled a hundred twenty-three subungual melanoma patients and, after excluding a large number lost to follow-up or without adequate imaging, two hundred ninety benign longitudinal melanonychia patients, all with clinical photos and dermoscopy, with a mean follow-up over two years for the benign group to make sure nothing was misclassified early. Three dermatologists blinded to final diagnosis independently rated standardized features — width relative to nail plate and to the melanonychia band itself, continuity, lateral border shape, proximal fading, and dermoscopic disappearance — with majority vote and reported interobserver agreement, which is a nice touch that adds some rigor to what is otherwise a fairly subjective visual assessment.

The results line up cleanly into a practical checklist. True Hutchinson's sign showed up in about eight in ten melanoma patients, while pseudo-Hutchinson's sign appeared in under half of the benign group — so its mere presence is not diagnostic on its own, which is exactly the clinical trap. What separated them was pattern, not presence. True Hutchinson's sign was significantly more likely to be wider than half the nail width, roughly eight in ten cases versus about two in ten for pseudo-sign, more likely to be wider than the melanonychia band itself, about four in ten versus essentially none, and more likely to be discontinuous, about half of cases versus almost never in the benign group. Conversely, pseudo-sign was overwhelmingly characterized by a straight, linear lateral border in essentially all cases versus only about one in ten true signs, and by proximal fading — a gradual lightening toward the cuticle — in the vast majority of benign cases versus a small minority of melanomas. And on dermoscopy, pseudo-sign vanished in about three-quarters of benign cases, while true Hutchinson's sign almost never disappeared. All of these differences were highly statistically significant, and importantly the effect sizes are large enough to be clinically meaningful, not just significant on paper — we're talking near-complete separation on some features like linear border and discontinuity. A subgroup analysis restricted to melanoma in situ showed the same pattern held even for early lesions, which matters because that's exactly the population where you're most anxious about missing something.

Limitations are honestly stated — single tertiary center, retrospective, and inherent subjectivity in color assessment, though they tried to objectify this with the fading concept and interobserver kappa values, which were generally in the fair-to-good range depending on the feature. Generalizability to a more diverse or non-Asian population with different baseline nail pigmentation patterns is also an open question, since acral lentiginous melanoma epidemiology differs by ethnicity.

Practically, this is a nice addition to your visual diagnostic toolkit rather than a practice-changing paper per se — you were already biopsying concerning longitudinal melanonychia with periungual change, and this doesn't change that threshold. But it gives you sharper language and criteria to reassure a patient and yourself when the periungual pigmentation is width-limited, has a linear border, fades proximally, and vanishes under the dermatoscope — features that lean benign — versus when it's wide, discontinuous, and dermoscopically persistent, which should keep your suspicion high regardless of how classic or subtle the underlying band looks.

Next, a major one — the first clinical practice guidelines for managing basal cell carcinoma in Gorlin syndrome, developed by a large multidisciplinary work group under the Gorlin Syndrome Work Group and senior author Murad Alam. This isn't a study, it's a formal guideline document, so we'll walk it through as such: the problem it addresses, the process by which consensus was built, and what the recommendations actually say.

The clinical problem is one you know well if you've managed even a handful of these patients — Gorlin syndrome patients accumulate basal cell carcinomas by the dozens to hundreds over a lifetime, and existing sporadic BCC guidelines simply don't map onto that reality. Surgical fatigue, disfigurement risk, curative versus palliative intent, psychosocial burden, and lifelong multidisciplinary coordination are all issues sporadic-BCC guidance was never built to handle, and until now there was no dedicated framework.

The methodology here is worth walking through because it's a genuinely rigorous process and a good model for how rare-disease guidelines should be built when the evidence base is thin. They used a modified GRADE approach — that's Grading of Recommendations Assessment, Development and Evaluation — which is standard for guideline development but was adapted here specifically because high-quality randomized data in Gorlin syndrome essentially doesn't exist. So rather than relying purely on trial evidence, they layered in a systematic literature review, expert evidence surveys from clinicians experienced with this population, structured patient interviews, and a two-round Delphi consensus process, culminating in a final consensus meeting. That blended approach — literature plus expert opinion plus patient voice — makes sense as the authors themselves frame it, precisely because the evidence gaps are so large that expert consensus has to fill in where trials can't. The panel was large, more than one hundred thirty members across dermatology, Mohs surgery, pediatric and adult genetics, oncology, psychiatry, psychology, and oral maxillofacial surgery, with patients and family members from the Gorlin Syndrome Alliance included directly on the panel — a nice detail, since this is explicitly framed as addressing psychosocial burden alongside tumor control. Conflict of interest was managed by requiring the majority of the panel be free of financial conflicts, and in the end eighty-seven percent were.

The output was sixty provisional recommendations winnowed down through the Delphi rounds and consensus meeting to forty-seven final recommendations, using a high consensus threshold above ninety percent agreement. These span topical therapies, systemic treatment, surgery, photodynamic and laser and other destructive modalities, radiation, monitoring and imaging protocols, and — notably — mental health, genetics counseling, financial burden, and lesion prioritization strategies for when a patient simply has too many tumors to treat all at once.

On substance: topical five-fluorouracil and imiquimod are recommended as first-line for low-risk tumors and field cancerization, specifically framed as tools to reduce surgical fatigue, and they're also endorsed for clearing positive superficial margins in low-risk lesions rather than reflexively re-excising everything. Hedgehog pathway inhibitors are recommended for patients with multiple low-risk tumors or for high-risk disease where surgery would cause significant functional impairment or disfigurement, with intermittent dosing strategies discussed to manage the well-known tolerability issues with chronic hedgehog inhibitor therapy.

There isn't a results-versus-limitations dichotomy here in the traditional research sense, but the authors are upfront about the core limitation of the whole undertaking: because Gorlin-specific high-quality data is so scarce, a substantial portion of these forty-seven recommendations rest on expert consensus rather than trial evidence, and they explicitly call for more research to strengthen the evidence base going forward.

For your practice, this one is genuinely practice-changing if you manage any Gorlin syndrome patients — it's the first time you have a structured, specialty-endorsed framework for sequencing topical, systemic, and surgical therapy, for deciding when a hedgehog inhibitor is appropriate rather than reserving it for after surgical options are exhausted, and for building psychosocial support and shared decision-making into a chronic care plan rather than treating each BCC as an isolated surgical encounter. Worth pulling the full tables for reference the next time you're mapping out a treatment sequence for one of these patients.

Now to two shorter pieces — JAAD Game Changer commentaries, which are retrospective looks at how an already-published study changed practice. First, on melanoma survival in adolescents and young adults. The original study, published in JAAD in twenty twenty-three, looked at over eighty-one thousand cutaneous melanoma patients and found something that runs counter to the usual assumption that younger patients simply do better — adolescents and young adults, defined here as ages fifteen to thirty-nine, actually had significantly worse survival than adults aged forty to sixty-four, and the gap was most pronounced for thick tumors, greater than four millimeters Breslow depth. The Game Changer authors frame the practical implication squarely around awareness and delay — if AYA patients and their primary care providers aren't attuned to melanoma risk in this age group, presentation skews later and thicker, and that's reflected in survival by insurance type and stage as well. The actionable takeaway isn't a change in your surgical or staging approach — it's a reminder to keep melanoma on the differential for young patients with a changing lesion, and to not let age alone reassure you or a referring provider into delaying biopsy.

Finally, the Game Changer on cutaneous squamous cell carcinoma recurrence timing, from a multicenter retrospective cohort of seven hundred eighty-two cSCC cases. The core finding is a clean, clinically actionable number: about fifty-five percent of recurrences, metastases, and deaths were detected within the first year after diagnosis, roughly eighty percent by two years, and about ninety percent by three years. In other words, the highest-yield surveillance window is squarely in that first three-year stretch, and events after that become progressively rare. The Game Changer commentary is appropriately measured about this — it notes that patient and tumor risk factors vary enormously, so this isn't a mandate to abandon longer follow-up, but it does give you a concrete, quotable number for counseling patients about their personal risk trajectory and for calibrating how aggressively you front-load visit frequency in those early years rather than spreading surveillance evenly over five or ten years. This is the kind of finding that's immediately useful at the chairside even though it doesn't overturn existing NCCN-style follow-up frameworks.

That wraps this episode. To summarize the through-line: sharper morphologic criteria for nail pigmentation, a landmark consensus framework for a rare but heavily surgery-dependent syndrome, and two reminders — one on age-based melanoma risk perception, one on front-loading cSCC surveillance — that are already shaping how we counsel and follow our patients. Thanks for listening, and I'll see you next month.