Mohs surgery for early-stage Merkel cell carcinoma (MCC) achieves local control better than wide local excision ± radiation therapy with no increase in MCC-specific death.

BACKGROUND: Merkel cell carcinoma (MCC) of the skin is most commonly treated with wide local excision (WLE) with or without adjuvant radiation therapy (RT). Mohs micrographic surgery (MMS) as monotherapy may offer an alternative treatment modality. The purpose of this study is to describe outcomes of patients with primary Stage I/II MCC treated with MMS alone and no RT. METHODS: A retrospectively collected sample of 56 MCCs treated with MMS was studied over an 18-year period. Tumor and treatment characteristics were described, and follow-up was assessed. RESULTS: A total of 56 primary Stage I/II MCCs in 53 patients were treated with MMS as monotherapy from April 2001 through July 2019. Patients were followed for an average of 4.6 years (median 2.7 years, range 0.8 to 16.9 years), of which 19 (33.9%) had follow-up of 5 years or more. There were no local recurrences due to inadequate excision. The 5-year Kaplan-Meier MCC-specific survival for AJCC8 Stage I and AJCC8 Stage IIA were 91.2% and 68.6%, respectively. CONCLUSION: In comparison to historical controls, Mohs surgery offers a survival that is at least as good as WLE +/- RT, with the added benefits of no need for adjuvant RT or the need for further surgery for treatment of local recurrence.

Margin Assessment for Punch and Shave Biopsies of Dysplastic Nevi.

INTRODUCTION: Biopsies of atypical melanocytic nevi are among the most commonly performed procedures by dermatologists. Margin assessment is often used to guide re-excision, but can be a point of confusion as negative margins reported in the planes of sections examined do not always reflect complete removal of a lesion. This study investigates the rates of false negative margins after both punch and shave biopsies. METHODS: We performed a retrospective analysis of 50 consecutive punch and shave biopsy specimens (1) diagnosed as DN, and (2) reported as having clear margins in the planes of section examined. Identified specimen blocks were then sectioned through to examine true margin involvement. RESULTS: Of the 50 specimens identified, 20% (n = 10) were found to have positive margins upon additional sectioning. We found no difference between the groups with respect to biopsy technique, type of nevus, degree of atypia, or gender. CONCLUSION: This study observed false negative peripheral margin status in a sizeable proportion of biopsy specimens, which did not vary significantly based on biopsy technique or pathologic characteristics. This finding reflects a limitation of standard tissue processing, in which a limited proportion of the true margin is evaluated, and may be of note to many dermatologists who base their decision to re-excise on the reporting of margin involvement. J Drugs Dermatol. 2018;17(7):810-812.

Intraoperative Immunostaining for Cytokeratin-7 During Mohs Micrographic Surgery Demonstrates Low Local Recurrence Rates in Extramammary Paget's Disease.

BACKGROUND: Extramammary Paget's disease (EMPD) is a rare intraepithelial malignancy with high recurrence rates following standard surgical treatments, ranging from 22% to 60% in large retrospective reviews. OBJECTIVE: To evaluate the local recurrence rate of Mohs micrographic surgery (MMS) supplemented with intraoperative immunohistochemistry for cytokeratin-7 (MMS + CK-7) for primary and recurrent EMPD. MATERIALS AND METHODS: Retrospective, multi-center, cross-sectional study of patients treated using MMS + CK-7. Demographic, clinicopathologic, treatment, and follow-up data were obtained by chart review. RESULTS: The observed local recurrence rate for MMS + CK-7 is 3.3% (2/61 tumors) with a mean follow-up of 43.5 months (1-120 months). Local recurrence occurred in 2.3% (1/43) of primary tumors and 5.6% (1/18) of recurrent tumors. Kaplan-Meier 5-year tumor-free rates are 94.6% overall, 97.1% for primary tumors, and 80.0% for recurrent tumors. The Kaplan-Meier 5-year tumor-free rates for all EMPD tumors treated with MMS + CK-7 versus a historical cohort of MMS alone are 94.6% versus 72.0% (p = .012). CONCLUSION: MMS + CK-7 is an effective treatment for EMPD, demonstrating improved outcomes compared with historical controls.

A prospective study evaluating the utility of a 2-mm biopsy margin for complete removal of histologically atypical (dysplastic) nevi.

BACKGROUND: Complete removal of individual dysplastic nevi (DN) is often accomplished by a second surgical procedure after the initial biopsy. The choice to perform the second procedure is strongly influenced by histopathologic margin status of the initial biopsy specimen. OBJECTIVE: To evaluate the clinical and histopathologic outcomes of in toto biopsy of DN using a predetermined margin of normal skin. METHODS: We conducted a prospective study of a saucerization method using a defined 2-mm margin in patients undergoing biopsy of a pigmented skin lesion. RESULTS: We performed 151 biopsies in 138 patients. Overall, 137 of 151 lesions subjected to biopsy (90.7%) were melanocytic: 86 DN (57.0%), 40 nevi without atypia (26.5%), and 11 melanomas (7.3%). Of 78 DN, 68 (87.2%) were removed with clear histopathologic margins (8 DN were excluded because of inadequate processing). There was no clinical evidence of recurrence at any of the biopsy sites that were simply observed (i.e., not re-excised) over a median of 16.9 months. LIMITATIONS: There were few biopsies performed on the face. CONCLUSIONS: The complete histopathologic removal of nearly 9 of 10 DN using a peripheral margin of 2 mm of normal skin and a depth at the dermis and subcutaneous fat junction has the potential to decrease second procedures at DN biopsy sites, thereby decreasing patient morbidity and saving health care dollars.

Effect of General Anesthesia on Neurodevelopmental Abnormalities in Children Undergoing Treatment of Vascular Anomalies With Laser Surgery: A Retrospective Review.

BACKGROUND: Multiple exposures to general anesthesia may be neurotoxic to the developing brain. This relationship has not been evaluated in children undergoing laser surgery for vascular anomalies. OBJECTIVE: To evaluate the prevalence of neurodevelopmental abnormalities in children who received multiple laser procedures under general anesthesia before the age of 4 years for the treatment of vascular anomalies. METHODS AND MATERIALS: Retrospective chart review of patients with contact of parents for telephone interview. RESULTS: Thirty-three patients were eligible. Average age at the time of survey was 7.8 years. Twenty-three (84.8%) patients were female, with average age at the time of first treatment at 1.9 years. Average number of treatments received before the age of 4 years was 6.7. Anesthetics included inhalational nitrous oxide and isoflurane and intravenous propofol. Seven patients carried one or more of the following diagnoses: attention-deficit hyperactivity disorder (3.0%), anxiety (6.1%), behavioral disorder (3.0%), language disorder (3.0%), speech disorder (3.0%), and motor disorder (6.1%). These prevalence rates are similar to those found in the US population. CONCLUSION: This is the first report on the prevalence of neurodevelopmental disorders in children undergoing multiple laser treatments under general anesthesia. Although the study sample is small, no increased risks when comparing with prevalence rates reported in the literature were noted.

Panfolliculoma with an endophytic architecture resembling a hair follicle: a report of three cases.

Panfolliculoma is a benign follicular tumor comprised of all components of the hair follicle. We report three cases of panfolliculoma with a solid, endophytic architecture, which at scanning magnification had the profile of a hair follicle. The epithelial components included uniform dark blue germinative cells, matrical cells, clear cells and cells containing trichohyaline granules. All the cases also had a central hyperkeratotic horn resembling a hair shaft. Two patients were female and one was male. Two lesions were located on the head and neck, and one was located on the leg. Clinical differential diagnoses included basal cell carcinoma, foreign body and cyst.

Skin-limited relapse of systemic anaplastic large-cell lymphoma.

Anaplastic large-cell lymphomas (ALCLs) are agroup of CD30-positive non-Hodgkin lymphomasthat are linked by common morphologic andimmunophenotypic features but have varyingclinical and genetic characteristics. The World HealthOrganization classification currently recognizes threesubtypes of ALCL: systemic anaplastic lymphomakinase-positive ALCL, systemic anaplastic lymphomakinase-negative (ALK-) ALCL, and primary cutaneousALCL. Here we present a 42-year-old man with ahistory of systemic ALK- ALCL, who was in remissionfor six months before relapsing with skin-limitedanaplastic large-cell lymphoma.