Welcome back to this Dermatologic Surgery journal review. This is the December twenty twenty-five issue, and we've got four pieces to walk through today — a technique article on removing a benign skull lesion, a cautionary case report on radiation therapy for nasal basal cell carcinoma, a database study on infection risk in immunosuppressed Mohs patients, and a cross-sectional look at gender representation in academic Mohs leadership. Let's get into it.

First up is a How We Do It piece on button osteoma removal, from David Harvey and colleagues out of Emory-affiliated practice in Georgia. This is a pure technique article, so there's no results section or limitations to speak of — just a description of their preferred surgical approach, and it's a nice one to have in your back pocket if you don't see these often. Button osteomas are benign, slow-growing, smooth bony lesions that show up most commonly on the parietal and frontal skull. They're usually asymptomatic, but patients present for removal because of pain, discomfort, or cosmetic concern. Diagnostically, the authors remind us that physical exam should assess firmness, mobility, and reducibility, that a Valsalva maneuver can help rule out an intracranial connection, that transillumination can pick up cystic change, and that imaging — plain film, CT, or Doppler ultrasound — adds information, with Doppler being particularly useful for assessing pulsatility, which obviously you'd want to know about before you take an osteotome to someone's skull.

Their technique itself: mark the incision parallel to relaxed skin tension lines to minimize the scar, then infiltrate one-percent lidocaine with epinephrine into both the skin and the subgaleal space. The incision starts transversely down to subcutaneous fat, then the plane changes to run parallel with the frontalis muscle fibers until you hit periosteum — sharp or blunt dissection, surgeon's preference, goal being a clean exposure without collateral tissue damage. The periosteum is then incised sharply along the base of the osteoma and elevated with either a periosteal elevator or blunt undermining scissors. Then comes the key maneuver — a one-centimeter straight osteotome is placed tangentially at the base of the lesion, and short mallet strikes separate the osteoma from the calvarium. Once it's fully freed, it's lifted out with forceps or a hemostat, the bony bed is smoothed if needed, and closure proceeds in layers — frontalis and skin — with absorbable suture, followed by a pressure dressing to control swelling and bleeding. The authors state this gives them high success rates and good cosmetic outcomes, though again, no actual outcomes data is presented here — this is a pearls-and-technique piece, not an outcomes study. The practical takeaway is straightforward: this is a clean, reproducible stepwise algorithm for a procedure most of us do infrequently enough that having an explicit roadmap — orientation of dissection along frontalis fibers, tangential osteotome placement, layered closure — is genuinely useful the next time one of these crosses your schedule.

Next, a case report: recurrent and infiltrative basal cell carcinoma of the nose after high-dose-rate electronic brachytherapy, from Ariel Park and Jason Castillo. This one is worth sitting with because it's a cautionary tale about treatment selection on the nose. A seventy-one-year-old woman with an extensive basal cell carcinoma history presented for Mohs surgery on a biopsy-proven recurrent nodular basal cell carcinoma of the left nasal tip. Ten years earlier she'd had a small, well-demarcated pearly plaque there — about one by one centimeter — initially trialed with six weeks of off-label topical five-fluorouracil, then biopsied and confirmed as nodular basal cell carcinoma. At that point she was offered Mohs surgery, declined it, and instead pursued radiation, receiving Xoft high-dose-rate electronic brachytherapy to the left nasal tip in 2015. She also went on, years later, to get superficial radiation therapy to a separate basal cell carcinoma on the right nasal sidewall, having been counseled that radiation would be a "scarless" procedure with a low recurrence rate.

Fast forward to presentation for Mohs: the lesion had grown to one-point-four centimeters with an ill-defined border, coarse telangiectasias, and surrounding hypopigmentation — already a very different clinical picture than the original tumor. Clearing margins took eight stages of Mohs, and histology now showed an infiltrative growth pattern invading epidermis, dermis, fat, and even muscle — a considerably more aggressive phenotype than the original nodular subtype. The resulting defect was four-point-two by three-point-two centimeters, reconstructed with an ear cartilage graft and an interpolated paramedian forehead flap — a big jump in complexity from what a primary excision of a one-centimeter nodular basal cell carcinoma would have required.

The discussion contextualizes this against the recurrence literature. Mohs surgery, the standard of care, carries roughly a one-percent five-year local recurrence rate for basal cell carcinoma, compared with around sixteen percent for superficial radiation therapy. High-dose-rate electronic brachytherapy specifically has generally reported better numbers than superficial radiation therapy — the authors cite a series of forty patients and sixty lesions with only a small partial-response rate around four to five percent at two years, a much larger series of over twelve hundred patients showing under one-percent recurrence at around sixteen months, and another elderly cohort with zero recurrences at a year. Pooling several other reports, recurrence after high-dose-rate brachytherapy ranges from none up to about eight percent across follow-up windows from a year out to a decade. So on paper, this modality generally performs reasonably well. But this case is the reminder that reasonably-low-average recurrence rates don't protect any individual patient, and when brachytherapy does fail, it can fail in a way that upstages the tumor's biology — nodular to infiltrative — and dramatically increases the size and complexity of the eventual salvage surgery. The authors' bottom line is not that brachytherapy is wrong, but that treatment selection needs to be a genuine shared decision, with patients told plainly that radiation carries real risks of scarring, and that if recurrence happens, it may not be a simple redo — it may be a more aggressive tumor requiring a much bigger operation than upfront Mohs would ever have needed. For practicing Mohs surgeons, this isn't new practice-changing data, but it's an excellent, concrete counseling anecdote for exactly the conversation many of us have multiple times a week with patients requesting a "no-cut" option for nasal basal cell carcinoma.

Third, an original retrospective database study: surgical site infections following Mohs surgery in immunocompromised patients, a multicenter look using the All of Us database, from Christopher Guirguis, Nicholas Flint, Michael Ramsey and colleagues at Geisinger and Georgetown. The background problem here is a familiar one — immunosuppression is a well-established general surgical risk factor for postoperative complications, but its specific relationship to surgical site infection after Mohs surgery has been murky, with prior work largely coming from single-institution datasets and conflicting conclusions. There was already a signal in the transplant literature of roughly a two-fold increase in surgical site infections among organ transplant recipients, but that literature specifically excluded patients on immunosuppressive agents unrelated to their transplant regimen. So this group wanted a broader net — using a large national database to look not just at "immunosuppressed versus not," but to break immunosuppression down by drug class and see which specific categories actually carry elevated risk.

Methodologically, they queried the All of Us database — which draws electronic health record data from a large, nationally representative population of over a quarter million participants — for Mohs cases using the relevant procedure codes, then looked backward two weeks preoperatively for prescriptions across a long list of immunosuppressive drug classes: steroids, TNF-alpha inhibitors, interleukin inhibitors, JAK inhibitors, other biologics like rituximab, calcineurin and mTOR inhibitors, antimetabolites, and several others. Infections were captured in thirty- and sixty-day postoperative windows, and they used multivariate regression to adjust for sex, race, ethnicity, and prior hyperlipidemia or hypertension diagnoses. The rationale for a database approach like this, though the authors don't spell it out explicitly beyond wanting a more representative population than single-center data, is fairly intuitive from a methodology standpoint — a database of this scale is really the only practical way to get enough patients on each individual immunosuppressive drug class to run separate subgroup analyses, something a single-institution retrospective chart review would almost never be adequately powered for.

The results: out of nearly eight thousand Mohs cases across roughly thirty-seven hundred patients, after excluding cases where patients had already been on antibiotics preoperatively, there was a statistically significant increased risk of postoperative infection across almost every immunosuppressive category examined. Steroids nearly doubled the odds at thirty days and nearly tripled it at sixty days. TNF-alpha inhibitors showed roughly a seven-fold increase at thirty days. The "other biologics" category — rituximab, alemtuzumab, and similar agents — showed the largest signal, on the order of a fifteen-fold increase at thirty days, though that group represents a genuinely small sample size, so treat the magnitude with real caution even though it was statistically significant. Calcineurin and mTOR inhibitors showed roughly a two-and-a-half to three-fold increase, antimetabolites showed a more modest but still significant increase of under two-fold, and overall, being on any immunosuppressive agent nearly doubled infection odds at both time points. JAK inhibitors, alkylating agents, anthracyclines, and taxanes couldn't be assessed at all due to insufficient patient numbers in those categories.

The authors are appropriately measured in their discussion. This directly challenges prior single-institution studies that had found no elevated surgical site infection risk with immunosuppression, and it extends the transplant-specific literature to a much broader immunosuppressed population — not just transplant patients. The honest limitations here are real: small sample sizes in some of the drug-class subgroups, meaning those very large point estimates — especially for the "other biologics" group — come with real statistical noise; and critically, an inability to confirm that the coded infection diagnoses were actually tied to the Mohs surgical site itself rather than some unrelated infection occurring in the same time window. It's a database study, so causality can't be established, only association. For practice, I'd call the overall signal — that immunosuppression as a category is associated with meaningfully higher surgical site infection risk after Mohs surgery — clinically important and worth incorporating into how you counsel and perhaps how you think about perioperative antibiotic use in patients on steroids, TNF inhibitors, calcineurin or mTOR inhibitors, or antimetabolites specifically. But I'd treat the exact magnitude for the smaller drug categories, particularly the "other biologics" group, as interesting rather than something to hang a specific prophylaxis protocol on until it's validated in a larger, better-adjudicated cohort.

Last, a cross-sectional study on trends in academic rank and leadership roles of male and female Mohs surgeons, from Katherine Wang, Naiara Barbosa, and colleagues at Mayo Clinic Jacksonville. The background here is workforce equity: women now make up over half of practicing dermatologists in the United States, yet a 2017 survey found only about a quarter of academic dermatology department chairs and Mohs fellowship directors were women. This study wanted an updated, more granular look specifically at Mohs surgeons in residency-affiliated academic positions — comparing academic rank, leadership titles, and publication output by gender.

Methodologically, they identified residency-affiliated Mohs surgeons through program websites as of March 2024, requiring completion of an American College of Mohs Surgery-accredited fellowship and residency affiliation, while excluding adjunct faculty, non-affiliated surgeons, current fellows, and anyone who'd only just finished fellowship. They pulled academic rank, leadership roles, publication counts via PubMed, years since fellowship, and geographic region, then used appropriate statistical models for each outcome type — proportional odds regression for rank, binary logistic regression for leadership presence, negative binomial regression for publication counts — importantly adjusting for geographic region and years out of fellowship, and then re-running everything stratified by career stage. The adjustment for years out of fellowship is methodologically the crux of this whole paper, because seniority is such an obvious confounder for both rank and publication count, and it's what separates the raw unadjusted comparison from the more meaningful one.

And that adjustment mattered enormously here. In the unadjusted analysis, male surgeons had significantly higher academic rank and significantly more publications than female surgeons. But once the authors adjusted for region and years out of fellowship, both of those differences lost statistical significance — meaning the apparent gender gap was substantially, though perhaps not entirely, explained by men in this cohort simply having more years in practice on average. Leadership role prevalence showed no significant difference between genders at any point, adjusted or not. When they stratified by career stage, the picture held for early-career surgeons — no significant differences in rank, leadership, or publications for those within their first ten years out of fellowship. Among more senior surgeons, eleven-plus years out, rank and leadership still showed no significant gender difference, but publication count did remain significantly higher for men even after adjustment — likely reflecting a longer average track record in that older cohort. Interestingly, when they sliced career stage even more finely into zero-to-five and six-to-ten-year bands, women six to ten years out actually had significantly more publications than men in the same band, a reversal that's worth noting even if the authors don't make much of it beyond flagging the finding.

Contextually, the authors point out this all sits against a backdrop of increasing parity — women went from under seven percent of dermatologists in 1970 to over half today, though they still make up only around twenty-eight percent of Mohs surgeons specifically, a proportion that has been climbing at fellowship match by less than a percentage point each year. Limitations are the ones you'd expect from this design: it's cross-sectional, so it's a single snapshot in time, and several of the stratified subgroup analyses are working with fairly small numbers, which limits precision. The practical takeaway here isn't clinical — there's no patient-care action item — but it is relevant to how our field thinks about mentorship, promotion committees, and fellowship recruitment. The reassuring headline is that once you account for experience, gender doesn't appear to be independently predicting rank or leadership attainment in this cohort, which is a meaningfully different and more optimistic message than the raw, unadjusted numbers alone would suggest. Whether that holds up as more women enter the pipeline and age into the senior-career bracket is exactly the kind of longitudinal question the authors say still needs following.

That wraps our four articles for this December issue — a practical technique for an uncommon bony lesion, a sobering brachytherapy recurrence case worth keeping in your counseling script, a database signal on immunosuppression and infection risk that's worth acting on cautiously, and an encouraging, if still evolving, picture of gender parity in academic Mohs leadership. Thanks for listening, and we'll see you next month.