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Acta Dermato-venereologica Apr 2024Nevus-associated lentigo maligna and lentigo maligna melanoma (NALMM) are rarely described in the literature and are considered an incidental finding. This study aimed...
Nevus-associated lentigo maligna and lentigo maligna melanoma (NALMM) are rarely described in the literature and are considered an incidental finding. This study aimed to evaluate the frequency of NALMM and its clinicopathological features. A total of 201 histopathology reports were reviewed and among them 20% of the samples corresponded to NALMM, with females overrepresented in this group (p = 0.02). A significant association was also observed between NALMM with the presence of multiple nevi (p = 0.01), and dysplastic nevi (p = 0.04). Moreover, the risk of developing a second melanoma of nevus-associated type was 4.3 times higher in patients with NALMM. These results indicate that NALMM is more frequent than previously reported, suggesting that the associated nevus could interact or even act as a precursor for LM/LMM. Future studies with larger samples allied to techniques like confocal microscopy and molecular analysis are essential to determine this biological link between nevus and LM/LMM.
Topics: Female; Humans; Hutchinson's Melanotic Freckle; Melanoma; Nevus, Pigmented; Nevus; Skin Neoplasms
PubMed: 38629956
DOI: 10.2340/actadv.v104.18381 -
Journal of Cutaneous Medicine and... Apr 2024
PubMed: 38613417
DOI: 10.1177/12034754241245979 -
Histopathology Jul 2024The histopathological classification of melanocytic tumours with spitzoid features remains a challenging task. We confront the complexities involved in the histological...
The histopathological classification of melanocytic tumours with spitzoid features remains a challenging task. We confront the complexities involved in the histological classification of these tumours by proposing machine learning (ML) algorithms that objectively categorise the most relevant features in order of importance. The data set comprises 122 tumours (39 benign, 44 atypical and 39 malignant) from four different countries. BRAF and NRAS mutation status was evaluated in 51. Analysis of variance score was performed to rank 22 clinicopathological variables. The Gaussian naive Bayes algorithm achieved in distinguishing Spitz naevus from malignant spitzoid tumours with an accuracy of 0.95 and kappa score of 0.87, utilising the 12 most important variables. For benign versus non-benign Spitz tumours, the test reached a kappa score of 0.88 using the 13 highest-scored features. Furthermore, for the atypical Spitz tumours (AST) versus Spitz melanoma comparison, the logistic regression algorithm achieved a kappa value of 0.66 and an accuracy rate of 0.85. When the three categories were compared most AST were classified as melanoma, because of the similarities on histological features between the two groups. Our results show promise in supporting the histological classification of these tumours in clinical practice, and provide valuable insight into the use of ML to improve the accuracy and objectivity of this process while minimising interobserver variability. These proposed algorithms represent a potential solution to the lack of a clear threshold for the Spitz/spitzoid tumour classification, and its high accuracy supports its usefulness as a helpful tool to improve diagnostic decision-making.
Topics: Humans; Nevus, Epithelioid and Spindle Cell; Machine Learning; Skin Neoplasms; Male; Female; Melanoma; Adult; Adolescent; Young Adult; Child; Middle Aged; Child, Preschool; Proto-Oncogene Proteins B-raf; Membrane Proteins; GTP Phosphohydrolases; Infant; Mutation; Aged
PubMed: 38606989
DOI: 10.1111/his.15187 -
Asian Journal of Surgery Jul 2024
Topics: Humans; Nevus, Pigmented; Melanoma; Mutation; Skin Neoplasms; Transcription Factors; Chromosomal Proteins, Non-Histone; Male; Female
PubMed: 38604858
DOI: 10.1016/j.asjsur.2024.03.171 -
Cureus Mar 2024Tissue expansion is a handy reconstructive technique for the head and neck region; however, its implementation requires careful planning and surgical experience. If...
Superficial Temporal Artery Island Flap Combined With Laser Hair Removal for Inadequate Skin Expansion Following Tissue Expansion: A Case Report of Congenital Melanocytic Nevus of the Forehead in an Adult.
Tissue expansion is a handy reconstructive technique for the head and neck region; however, its implementation requires careful planning and surgical experience. If tissue expansion is inadequate, forced closure results in wound tension and risks complications, such as postoperative deformity, wide scarring, and wound dehiscence. We report a case of adult forehead melanocytic nevus excision using a tissue expander (TE) where complications caused by insufficient tissue expansion were avoided by creating a flap using a dog ear. The patient was a male in his 20s who underwent surgery with a TE for a congenital melanocytic nevus sized 15 × 10 cm on the left forehead. Resection was performed by tissue expansion using two TEs; however, simple advancement flaps led to excessive wound tension, risk of elevation of the eyebrow on the affected side, and postoperative scarring. Hence, a superficial temporal artery fasciocutaneous island flap with left superficial temporal vessels as a pedicle was raised at the dog ear and moved to the site of strong tension, and the wound was closed without difficulty. Although postoperative laser hair removal was required, both the appearance and functional results were satisfactory. Using anatomical flaps obtained from the surroundings during tissue expansion helps avoid complications associated with forced wound closure.
PubMed: 38601411
DOI: 10.7759/cureus.55920 -
Indian Journal of Dermatology,... Mar 2024
PubMed: 38594984
DOI: 10.25259/IJDVL_1110_2023 -
American Family Physician Mar 2024Birthmarks in newborns can be classified as vascular, melanocytic or pigmented, or markers of underlying developmental abnormalities of the nervous system. A nevus...
Birthmarks in newborns can be classified as vascular, melanocytic or pigmented, or markers of underlying developmental abnormalities of the nervous system. A nevus simplex is a benign capillary malformation. Newborns with a nevus flammeus can be safely treated before one year of age with a pulsed dye laser to reduce the visibility of lesions. Infantile hemangiomas should be treated with systemic beta blockers if there is a risk of life-threatening complications, functional impairment, ulceration, underlying abnormalities, permanent scarring, or alteration of anatomic landmarks. Dermal melanocytosis is a benign finding that is easily recognized and does not warrant further evaluation. A solitary congenital melanocytic nevus that is less than 20 cm in diameter may be observed in primary care; children with larger or multiple nevi should be referred to pediatric dermatology due to the risk of melanoma. Newborns with skin markers of occult spinal dysraphism (other than a simple, solitary dimple) should have lumbar spine imaging using ultrasonography or magnetic resonance imaging.
Topics: Child; Humans; Infant, Newborn; Nevus, Pigmented; Skin Neoplasms; Skin; Melanoma; Magnetic Resonance Imaging
PubMed: 38574211
DOI: No ID Found -
The Australasian Journal of Dermatology Jun 2024Although excision of melanocytic nevi with high-grade dysplasia is recommended by the World Health Organization (WHO), clinical studies investigating the approach based...
BACKGROUND/OBJECTIVES
Although excision of melanocytic nevi with high-grade dysplasia is recommended by the World Health Organization (WHO), clinical studies investigating the approach based on the grading dysplasia of melanocytic lesions with peripheral globules (PGs) are lacking. We investigated the grades of dysplasia and their distinguishable dermoscopic and clinical features to provide accurate data for managing these lesions.
METHODS
We retrospectively classified histologically confirmed melanocytic lesions with PGs according to the 2018 WHO Classification of Skin Tumours criteria in a university hospital in Turkey. Dermoscopic features, lesions, and patient characteristics were recorded.
RESULTS
Sixty-six lesions of 56 patients were included. After classification, 9.1% (n: 6) of lesions were melanomas, 39.4% (n: 26) were high-grade dysplastic nevi, and 50% (n: 33) were low-grade dysplastic nevi (n: 33, 50%). There was one nevus with no dysplasia (n: 1, 1.5%). Univariate analysis revealed that ≥31 years of age, irregular shape of peripheral globules, black colour, total colour count, and maximum diameter of the lesion were associated with high-grade dysplasia and melanoma. In the multivariate analyses, ≥31 years of age (OR = 3.80, 95% CI, 1.17-12.37), irregular shape of peripheral globules (OR = 3.90, 95% CI, 1.15-13.2), and total colour count (OR = 3.21, 95% CI, 1.2-8.5) were significant predictive factors for the lesions with high-grade dysplasia and melanomas.
CONCLUSIONS
To avoid the underdiagnosis of both melanomas and high-grade dysplastic nevi with PGs, the irregular shape of peripheral globules and multiple colours after the third decade may be useful in making an excision decision. The risk increases every 1-year increase in age. Excision is suggested for all melanocytic lesions with PGs for patients 60 years or older because of the high risk of melanoma and melanocytic nevus with high-grade dysplasia.
Topics: Humans; Male; Skin Neoplasms; Female; Melanoma; Retrospective Studies; Adult; Middle Aged; Nevus, Pigmented; Dysplastic Nevus Syndrome; Dermoscopy; Young Adult; Aged; Adolescent; Neoplasm Grading; Age Factors
PubMed: 38572867
DOI: 10.1111/ajd.14261 -
Pediatric Dermatology Apr 2024A 4-month-old male presented for a large, hypertrichotic brown patch on the upper back with several scattered 0.5-1.5 cm, round to oval, brown macules and patches on...
A 4-month-old male presented for a large, hypertrichotic brown patch on the upper back with several scattered 0.5-1.5 cm, round to oval, brown macules and patches on the trunk and extremities. The lesion was initially diagnosed as a giant congenital melanocytic nevus based on clinical exam and histopathology with immunohistochemical stains. The patient was later diagnosed with neurofibromatosis type 1, and the lesion on the back developed a "bag of worms" texture consistent with a plexiform neurofibroma and found to harbor a pathogenic variant in the NF1 gene. This case highlights the diagnostic challenge of differentiating these lesions and their overlapping clinical and histopathological features.
PubMed: 38561464
DOI: 10.1111/pde.15611 -
Annals of Plastic Surgery Apr 2024The natural history of pediatric melanonychia and the necessity of biopsy for ruling out melanoma are debated in the literature. We hypothesize that there is a low rate...
HYPOTHESIS
The natural history of pediatric melanonychia and the necessity of biopsy for ruling out melanoma are debated in the literature. We hypothesize that there is a low rate of malignant nail pathology among pediatric patients undergoing nail bed biopsy for melanonychia.
METHODS
We performed a retrospective chart review of 54 pediatric patients (age <18 years) at a single institution who presented with melanonychia and underwent nail bed biopsy from 2007 to 2022. Data points collected included patient demographics, medical history, physical exam findings, pathology reports, and clinical photos. Univariate and multivariate analyses were performed to assess for risk factors associated with high-risk pathology findings.
RESULTS
The average age of melanonychia onset was 5.5 years (SD 4.4). The average age of first biopsy was 7.8 years (SD 4.3). On physical exam, 27 patients had at least four features concerning for melanoma (asymmetry, border irregularity, color heterogeneity, diameter > 1/3 of nail, evolving color, evolving diameter, Hutchinson's sign). The most common pathology diagnoses were melanocytic nevus (35%), atypical intraepidermal melanocytic proliferation (AIMP) with benign features (24%), subungual lentigo (22%), and AIMP with concerning features (17%). There were no cases of melanoma in situ or invasive malignant melanoma. On multivariate regression, the only significant risk factor associated with more concerning pathology (AIMP with concerning features) was the calendar year in which biopsy was performed (coefficient = -0.34, P = 0.016). There was no association between physical exam features and high-risk pathology. Twelve patients had surgical re-excision of the lesion, 6 of which were due to incomplete excision of AIMP with concerning features and 6 of which were due to recurrence.
CONCLUSIONS
Our case series did not find any cases of melanoma in situ or malignant melanoma arising from pediatric melanonychia. Atypical intraepidermal melanocytic proliferation with concerning features was associated only with the year in which the biopsy was performed, which may reflect the improved understanding of pediatric melanonychia as often benign despite concerning features on pathology. The decision to perform a nail matrix biopsy in pediatric melanonychia should be based on a collaborative discussion between the patient's parents, dermatologist, and plastic surgeon.
Topics: Child; Humans; Child, Preschool; Adolescent; Melanoma; Retrospective Studies; Nail Diseases; Skin Neoplasms; Nails; Melanoma, Cutaneous Malignant
PubMed: 38556653
DOI: 10.1097/SAP.0000000000003865