Length-to-width ratio in Mohs defects: what is the golden rule?

A length-to-width ratio (LWR) of 3:1 for linear closures is often cited in the literature. However, there are limited studies evaluating this ratio in relation to various surgical sites. This study analyzes LWRs for 3318 patients undergoing Mohs micrographic surgery (MMS) and linear repair to identify the average LWRs stratified by patient age, anatomic location, gender, and surgeon. Average LWRs ranged between 2.89 and 3.82. The LWR for all anatomic sites averaged between 3:1 and 4:1, except for closures on the trunk. Locations with the highest LWR included the cheek, ear, and perioral sites.

The Association of Academic Cosmetic Dermatology: improving cosmetic dermatology education through collaboration, research, and advocacy.

Cosmetic and laser procedures are increasingly popular among patients and are skills in which dermatologists are regarded as well trained. Most dermatology residents intend to incorporate cosmetic procedures into their practice and prefer to learn such procedures during residency through direct patient care. However, there are notable challenges in optimizing how residents are trained in cosmetic and laser dermatology. To address these barriers and elevate the practice of cosmetic dermatology in academic medicine, the Association of Academic Cosmetic Dermatology (AACD) was founded in 2021 as the lead professional society for dermatologists who direct the education of resident trainees in cosmetic and laser dermatology. The AACD, a group of board-certified dermatologists who teach cosmetic and laser dermatology to residents, aims to improve cosmetic dermatology education through collaboration, research, and advocacy.

Needs and Gaps in Resident Trainee Education, Clinical Patient Care, and Clinical Research in Cosmetic Dermatology: Position Statement of the Association of Academic Cosmetic Dermatology.

Cosmetic dermatology is a key subspecialty of academic dermatology. As such, academic centers are expected to demonstrate excellence in the teaching of cosmetic dermatology skills to trainees, the clinical delivery of cosmetic dermatology services to patients, and the performance of clinical research that advances knowledge and uncovers new therapies in cosmetic dermatology. The Association of Academic Cosmetic Dermatology (AACD), a newly formed medical professional society, includes as its principal aims the support of all of these areas. AACD is comprised of group of board-certified dermatologists who teach cosmetic and laser dermatology at US dermatology residency programs. An expert panel constituted by the AACD recently convened a workshop to review gaps pertaining to academic cosmetic dermatology. This panel considered needs and potential corrective initiatives in three domains: resident education, patient experience, and clinical research. The work of the panel was used to develop a roadmap, which was adopted by consensus, and which will serve to guide the AACD moving forward.

Chronic myeloid leukemia-leukemia cutis mimicking a neutrophilic panniculitis-like leukemia cutis: Report of a rare case.

While drug-induced panniculitis is not uncommon in chronic myeloid leukemia (CML) patients on tyrosine kinase inhibitor therapy, it is rare for CML to initially present as a leukemic panniculitis. We present the case of a 45-year-old male with no relevant prior medical history presenting with 6 months of migratory nodules, 2 months of drenching night sweats, and a 20 pound weight loss. Physical examination showed firm subcutaneous nodules with overlying ecchymoses present on the right lateral thigh and left lower back. Biopsy of a nodule from the right thigh showed a subcutaneous lobular panniculitis involved by a dense infiltrate of neutrophils and granulocyte precursors. Fluorescent in-situ hybridization (FISH) was positive for t(9;22)(q34;q11.2)BCR-ABL1 fusion. A concurrent hemogram revealed a white blood cell count elevation of 600,000 K/µL. Bone marrow biopsy examination showed marked myeloid expansion with an increase in granulocyte precursors and Philadelphia chromosome positivity by FISH, consistent with bone marrow involvement by CML. Herein, we describe this unusual and rare case of CML initially presenting as a neutrophilic panniculitis-like leukemia cutis. Arriving at this challenging diagnosis may be easily missed without clinical and laboratory correlation, which would certainly lead to the patient's not receiving life-saving treatment.

Sensitivity of fluorescence in situ hybridization for melanoma diagnosis using RREB1, MYB, Cep6, and 11q13 probes in melanoma subtypes.

OBJECTIVE: To evaluate the diagnostic sensitivity of fluorescence in situ hybridization (FISH) using probes targeting 6p25, 6q23, 11q13, and Cep6 in melanoma subtypes. DESIGN: Blinded comparison of chromosomal copy number changes detected using FISH targeting 6p25, 6q23, 11q13, and Cep6 in benign nevi and melanoma subtypes. SETTING: Dermatopathology Laboratory, Department of Dermatology, Northwestern University, Chicago, Illinois. PARTICIPANTS: One hundred ten individuals with benign nevi and 123 with melanoma (70 superficial spreading, 28 lentigo maligna, 22 nodular, and 3 acral lentiginous melanomas). MAIN OUTCOME MEASURES: Sensitivity of previously developed criteria using FISH using probes targeting 6p25, 6q23, 11q13, and Cep6 in the melanoma subtypes. RESULTS: Overall, sensitivity was 83.0% and specificity was 94.0%. The 6p25 gain criterion had the highest sensitivity overall and in each subtype. The assay was most sensitive in the subgroups of nodular and acral melanomas and least sensitive in the superficial spreading subtype. The 11q13 gain was more commonly seen in chronically sun-damaged skin and infrequently in non-chronically sun-damaged skin. CONCLUSIONS: Heterogeneous changes in melanoma occur at the molecular level, and the changes are different among melanoma subtypes. Clonal abnormalities in chromosome 6 with increased copies of the short arm relative to the long arm are common in all melanoma subtypes, suggesting that isochromosome 6 is common in all variants of cutaneous melanoma subtypes. An increase in copy number of 11q13 is most frequent in chronically sun-damaged melanomas.

Fluorescence in situ hybridization for distinguishing nevoid melanomas from mitotically active nevi.

Nevoid melanoma may resemble benign compound or intradermal nevi by their silhouette and profile on low power. Higher power usually reveals nuclear atypia, confluence of cells, incomplete maturation and dermal mitotic activity. However, to some extent all of these features maybe seen in benign compound or intradermal nevi and no single criteria can be used to differentiate nevoid melanoma from a benign nevus. The distinction can be particularly problematic in nevi that show mitotic activity and we have noted a recent trend in diagnosis of melanocytic neoplasms with dermal mitosis as nevoid melanoma despite the presence of normal maturation in the dermis and lack of significant nuclear atypia. Therefore in this study we evaluated 10 nevoid melanomas, 4 of which resulted in metastasis and 10 mitotically active nevi with fluorescence in situ hybridization targeting key chromosomal loci previously shown to effectively discriminate been malignant and benign melanocytic neoplasms. All 10 nevoid melanomas showed copy number abnormalities by fluorescence in situ hybridization in either chromosome 6 or 11 while none of the 10 mitotically active nevi did. The results demonstrate that fluorescence in situ hybridization targeting key chromosomal loci on chromosomes 6 and 11 can be effective in discriminating nevoid melanomas from mitotically active nevi. Additionally, our study presents further evidence that dermal mitoses alone without other diagnostic features such as nuclear atypia and lack of maturation does not constitute sufficient evidence alone for a diagnosis of melanoma.

Distinguishing epithelioid blue nevus from blue nevus-like cutaneous melanoma metastasis using fluorescence in situ hybridization.

Blue nevus (BN)-like cutaneous melanoma metastasis is a well-recognized variant of melanoma metastasis. These lesions may clinically and histologically simulate benign blue nevi. The histologic changes may be indistinguishable from conventional blue nevi or epithelioid blue nevi (EBN), a benign dermal-based melanocytic neoplasm with epithelioid morphology and heavily pigmented cytoplasm. Distinguishing BN-like cutaneous melanoma metastasis from benign conventional or EBN is important for staging and treatment. We evaluated a fluorescence in situ hybridization (FISH) assay using probes targeting 6p25 (RREB1), 6q23 (MYB), 11q13 (CCND1), and centromere 6 (Cep6) with previously determined criteria, to distinguish EBN and BN-like melanoma metastasis. Ten BN-like cutaneous melanoma metastatic lesions and 10 EBN were blindly evaluated with the above mentioned FISH probes. FISH enumeration and criteria for diagnosis of melanoma was as previously described. Nine of 10 BN-like cutaneous metastatic lesions showed significant aberrations and met previously established criteria for melanoma. None of the EBN cases showed evidence of significant copy number changes or met FISH criteria for a diagnosis of melanoma. FISH is an important diagnostic adjunct for melanocytic neoplasms. In this study, we show that a FISH assay targeting 6p25, 6q23, 11q13, and centromere 6 can distinguish EBN from BN-like metastatic melanoma with high accuracy. The test and the parameters previously established can perform with high sensitivity and specificity when dealing with this differential diagnosis.

Fluorescence in situ hybridization as a tool for microstaging in malignant melanoma.

Up to 30-50% of melanomas arise in association with a nevus. Accurately defining, the nevus from the melanoma can significantly affect microstaging. Recently, we showed that a targeted fluorescence in situ hybridization (FISH) assay could distinguish between benign nevi and melanoma with a sensitivity of 87% and specificity of 95%. In this study, we evaluated the potential of this same assay for use in the microstaging of melanoma. We performed FISH on 36 cases of melanoma occurring in association with a nevus and 6 cases of nevoid melanoma with deep dermal involvement. In the melanomas with associated benign nevi, FISH enumeration was performed separately on the histologically malignant and benign components. In the nevoid melanomas, FISH was performed on the deep dermal areas. On the basis of the criteria developed in our earlier studies, we determined the sensitivity of the assay within the malignant areas and the specificity within the benign areas of melanomas with associated nevi. In addition, we evaluated the sensitivity and specificity within a group of six nevoid melanomas with deep dermal involvement. Among melanomas with associated nevi, 28 of 36 cases (78%) tested positively in the histologically malignant areas. The benign nevus components were uniformly negative for all criteria. Six of six nevoid melanomas (100%) tested positively in the deep dermal area. FISH analysis with probes targeting 6p25, 6q23, 11q13 and CEP6 can effectively discriminate the malignant and benign components of melanomas with associated nevi and can be used as an adjunctive tool for microstaging. The assay has high sensitivity for the malignant areas of nevus-associated melanomas and outstanding specificity for the benign areas. The sensitivity is independent of the morphological features, and the assay performs well in nevoid melanoma cases.