Welcome to this July twenty twenty-six review of the Journal of the American Academy of Dermatology, where we cover four articles relevant to Mohs surgery and dermatologic oncology, spanning Merkel cell carcinoma radiation outcomes, an ethics case on same-day squamous cell carcinoma treatment, and two correspondence pieces on acral melanoma biopsy technique and prognosis by anatomic site.

Let's start with the first article, "Adjuvant radiation therapy is not associated with improved survival in low-risk localized Merkel cell carcinoma: an Analysis of the National Cancer Database," by Kasheri, Zumsteg, Kodumudi, Gharavi, and Rosenthal.

The clinical question here is whether adjuvant radiation therapy improves overall survival in patients with National Comprehensive Cancer Network defined low-risk, localized Merkel cell carcinoma, a population in which guidelines already suggest radiation may be omitted, but where robust risk-stratified survival data have been lacking. This was a retrospective cohort study using the National Cancer Database from 2010 to 2020, identifying patients with stage one to two, pathologically node-negative Merkel cell carcinoma treated surgically. Patients were stratified as low-risk or high-risk based on the presence of National Comprehensive Cancer Network adverse features, specifically tumor size greater than one centimeter, head or neck primary site, lymphovascular invasion, or immunosuppression. The final cohort included two thousand sixty-seven patients, with a median follow-up of fifty-four point six months. Of these, three hundred seventy-six patients, or eighteen point two percent, were low-risk, and one thousand six hundred ninety-one, or eighty-one point eight percent, were high-risk. Analysis used propensity score-matched Kaplan-Meier curves, adjusted Cox proportional hazards models, and landmark analyses at three, six, and twelve months to address immortal time bias.

The key finding: in low-risk patients, radiation was not associated with improved overall survival. Comparing one hundred forty-two patients who received radiation versus two hundred thirty-four who did not, five-year overall survival was eighty-five percent versus seventy-nine point one percent, with a hazard ratio of zero point seven-eight and a p-value of zero point two-nine, non-significant. In contrast, among high-risk patients, comparing eight hundred seventy-five who received radiation versus eight hundred sixteen who did not, radiation was associated with significantly improved survival, five-year overall survival seventy-one point six percent versus sixty-four point two percent, hazard ratio zero point seven-three, p less than zero point zero-zero-one. Landmark analyses confirmed this pattern. Notably, within the high-risk group, head and neck tumors were less likely to receive radiation than other high-risk features, thirty-nine point nine percent versus fifty-one point two percent, p less than zero point zero-zero-one, despite head and neck location itself being an independent risk factor for mortality in the multivariable model, with a hazard ratio of one point four-seven.

The evidence-based takeaway for surgical practice is that this large-scale, risk-stratified analysis validates the National Comprehensive Cancer Network criteria for identifying patients in whom adjuvant radiation may be safely omitted after surgery, since the absolute survival benefit in low-risk, node-negative disease was modest and not statistically significant. In high-risk patients, radiation showed a consistent and significant survival benefit, supporting its continued use in that group. The authors note that the lack of benefit in low-risk patients likely reflects a low baseline cancer-specific mortality, such that any relative reduction in recurrence risk from radiation does not translate into a measurable survival gain.

Methodological limitations include the retrospective design, and the absence of disease-specific survival, progression-free survival, distant metastasis-free survival, and locoregional recurrence data, meaning conclusions are limited strictly to overall survival endpoints.

Moving to the second article, "Ethical Considerations in Same-Day Surgical Treatment of a High-Risk, Poorly Differentiated Squamous Cell Carcinoma," by Mitchell, Afrin, Wahood, and Negbenebor.

This is an ethics-focused correspondence structured as a case consultation rather than an original data study, so there are no sample sizes or effect estimates to report. The clinical scenario presented is a patient from a rural area who traveled three hours for consultation of a biopsy-proven two-centimeter poorly differentiated squamous cell carcinoma on the temple, expecting same-day Mohs surgery because of transportation barriers and time constraints. The question posed is how to balance timely treatment against the need for further workup in patients facing socioeconomic barriers.

The piece frames its reasoning around the four classic biomedical ethics principles. On beneficence, it notes that small, superficial nonmelanoma skin cancers in immunocompetent patients are routinely managed with same-day evaluation and treatment, reducing visits and healthcare utilization. On nonmaleficence, it emphasizes that this particular tumor, a two-centimeter poorly differentiated squamous cell carcinoma, carries high metastatic potential and risk of local recurrence, particularly with perineural or lymphovascular invasion, large size at or above two centimeters, or central facial location, per the Schmults 2013 risk-factor data cited in the piece. These features may warrant additional workup, such as imaging, before definitive surgery, since proceeding without adequate evaluation risks underestimating tumor extent and incomplete staging. The authors state explicitly that additional workup, when indicated, should not delay treatment but may influence surgical planning or prompt multidisciplinary evaluation, including consideration of neoadjuvant programmed death-1 inhibitor therapy in high-risk cutaneous squamous cell carcinoma per National Comprehensive Cancer Network guidelines.

On justice, the authors discuss patient-specific barriers, time, financial strain, transportation, and suggest early communication with referring physicians, photographic documentation, local imaging arrangement, and teledermatology to facilitate planning. They also flag health system constraints, staffing, resource allocation, prior authorization, and reimbursement structures such as non-payment of separately billed evaluation and management services performed same-day as a procedure, as factors that can disincentivize same-day treatment but should never override clinical urgency or patient safety.

The evidence-based takeaway for surgical practice: same-day treatment decisions for high-risk cutaneous squamous cell carcinoma should be individualized based on tumor risk features and surgeon experience and institutional resources, but socioeconomic and logistical pressures should not lower the standard of care. Informed consent should explicitly address prognosis, potential need for complex reconstruction, and possible adjuvant therapy. As this is an ethics commentary rather than a data-driven study, there are no methodological limitations in the traditional sense to report, and no effect sizes or outcome rates are provided.

The third article is a letter, "Incise parallel, section perpendicular to the dermatoglyphs for diagnosis of acral melanocytic lesions, a comment on Thakker et al.," by Phelan and Shalin.

This is a technical correspondence clarifying biopsy orientation guidance from a prior review on acral lentiginous melanoma. There is no clinical trial data here, rather a conceptual and anatomic clarification. The authors point out that the original Thakker et al. review, and its cited source, recommended cutting incisional biopsies perpendicular to the dermatoglyphs on palms and soles. Phelan and Shalin argue this recommendation conflates two distinct steps, surgical incision versus pathological gross sectioning, and that the desired orientation actually differs between the two, though both converge on the same practical biopsy design.

Specifically, they explain that fusiform incisional designs should be oriented transversely across flexures to minimize risk of hypertrophic scarring, contracture, and web formation after linear closure, standard plastic surgery principle. Since dermatoglyphs run nearly transversely across flexures of the digits, palms, and soles, a fusiform incision oriented parallel to the dermatoglyphs achieves this transverse-to-flexure orientation and optimizes wound healing. Separately, in the pathology lab, standard gross sectioning of fusiform specimens follows a breadloafing technique perpendicular to the long axis. On acral skin, sectioning perpendicular to the dermatoglyphs is preferred because it allows visualization of the rete ridge and suprapapillary arrangement of melanocytes, whereas sectioning parallel to the dermatoglyphs can create a false impression of melanocytic confluence in benign acral nevi, a potential diagnostic pitfall.

The key clarification, and the evidence-based takeaway for surgical practice, is that incising, that is, designing the surgical fusiform biopsy, nearly parallel to the dermatoglyphs simultaneously satisfies optimal wound healing and, because standard breadloafing sectioning is performed perpendicular to the long axis of the fusiform specimen, automatically yields sections that are perpendicular to the dermatoglyphs for pathologic interpretation. In other words, a single biopsy design, oriented parallel to the dermatoglyphs, achieves both goals; the original phrasing describing incision as perpendicular to the dermatoglyphs was transposed. For non-flexural acral sites such as digit pads, where dermatoglyphs form nonlinear loops or whorls, the authors suggest proactive communication with the dermatopathologist or bedside grossing with bisection in the optimal orientation. As a letter without original data, there are no sample sizes, effect sizes, or statistical outcomes, and no methodological limitations beyond the conceptual clarification itself.

The fourth article is another letter, "Re: Effect of anatomical site on prognosis and progression pattern in early-stage acral melanoma, a retrospective cohort study of two hundred eighty-one cases," authored by Tooba, Khan, Talha, Shah, and Hasan, responding to the original Choi et al. study.

This correspondence raises methodological critiques of the original two hundred eighty-one case retrospective cohort comparing upper- versus lower-limb acral lentiginous melanoma prognosis and progression patterns; it does not present new primary data itself. The letter's substantive points are as follows. First, the authors note that the original study's comparison of first lymph node metastasis between upper and lower limb acral lentiginous melanoma did not account for fundamental anatomic differences in lymph node basin size and lymphatic flow between the two limbs, which could independently explain differences in nodal metastasis rates rather than reflecting true site-based tumor biology.

Second, they raise concern that using "first metastasis" as an endpoint may be confounded by variation in surveillance strategy, imaging technique, and follow-up frequency, referencing detection-bias literature from Francken and colleagues. They acknowledge the original study did account for imaging type, and that overall nodal involvement was similar between groups, tempering this critique somewhat.

Third, they highlight that sentinel lymph node biopsy results were not incorporated into the original study's staging, which they argue affects the precision of staging and surveillance timing, since without stratification by sentinel node status, observed nodal involvement patterns may reflect diagnostic practice variation rather than underlying tumor biology, citing the Morton et al. Multicenter Selective Lymphadenectomy Trial and a meta-analysis on sentinel node sensitivity and negative predictive value.

Fourth, the letter notes that stage two patients showed the strongest associations in the original study, but that this stage group is biologically heterogeneous and unevenly distributed across anatomic sites, and that the reported increased systemic metastasis risk in upper-limb acral lentiginous melanoma may be driven by small subgroup case numbers, limiting statistical robustness; the authors recommend a stage-stratified comparison across substages two-A, two-B, and two-C with sensitivity analyses.

Fifth, they critique the grouping of palm, finger, and nail unit melanomas together under a single "upper limb" category, arguing these subsites differ in embryological origin, mechanical stress, vascularization, and lymphatic drainage, referencing Wei and colleagues' clinicopathologic comparison across acral melanoma primary sites, and that this grouping may mask true site-specific associations.

The evidence-based takeaway for surgical and oncologic practice is a call for future acral melanoma research to stratify outcomes by sentinel lymph node biopsy status, evaluate lymphatic basins specifically rather than assuming equivalence between limbs, standardize surveillance and imaging protocols, and use more granular anatomical classification rather than broad upper- versus lower-limb groupings. As a letter to the editor, this piece offers no original sample size or effect data of its own; its contribution is entirely methodological critique of the referenced study.

That concludes this month's review. In summary, the Merkel cell carcinoma database analysis supports omitting adjuvant radiation in National Comprehensive Cancer Network defined low-risk, node-negative disease while reinforcing its survival benefit in high-risk disease; the ethics correspondence reinforces that socioeconomic pressures for same-day treatment must not compromise oncologic workup in high-risk squamous cell carcinoma; and the two acral melanoma letters, one on biopsy technique and one on anatomic site prognosis, both underscore the importance of precise technique and rigorous methodological stratification in this diagnostically challenging melanoma subtype. Thank you for listening to this July twenty twenty-six review.