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Lancet (London, England) Aug 2023Cutaneous melanoma is a malignancy arising from melanocytes of the skin. Incidence rates are rising, particularly in White populations. Cutaneous melanoma is typically... (Review)
Review
Cutaneous melanoma is a malignancy arising from melanocytes of the skin. Incidence rates are rising, particularly in White populations. Cutaneous melanoma is typically driven by exposure to ultraviolet radiation from natural sunlight and indoor tanning, although there are several subtypes that are not related to ultraviolet radiation exposure. Primary melanomas are often darkly pigmented, but can be amelanotic, with diagnosis based on a combination of clinical and histopathological findings. Primary melanoma is treated with wide excision, with margins determined by tumour thickness. Further treatment depends on the disease stage (following histopathological examination and, where appropriate, sentinel lymph node biopsy) and can include surgery, checkpoint immunotherapy, targeted therapy, or radiotherapy. Systemic drug therapies are recommended as an adjunct to surgery in patients with resectable locoregional metastases and are the mainstay of treatment in advanced melanoma. Management of advanced melanoma is complex, particularly in those with cerebral metastasis. Multidisciplinary care is essential. Systemic drug therapies, particularly immune checkpoint inhibitors, have substantially increased melanoma survival following a series of landmark approvals from 2011 onward.
Topics: Humans; Melanoma; Skin Neoplasms; Ultraviolet Rays; Sentinel Lymph Node Biopsy; Lymph Node Excision; Melanoma, Cutaneous Malignant
PubMed: 37499671
DOI: 10.1016/S0140-6736(23)00821-8 -
Current Ophthalmology Reports Dec 2023To provide an up-to-date review of the epidemiology, presentation, diagnosis, and treatment options for conjunctival nevi (CN).
PURPOSE OF REVIEW
To provide an up-to-date review of the epidemiology, presentation, diagnosis, and treatment options for conjunctival nevi (CN).
RECENT FINDINGS
Around 17.2%-42% of all conjunctival tumors have been found to be CN, which most frequently present in White individuals between the first to early third decade of life, with equal distribution between males and females. CN commonly occur in the interpalpebral bulbar conjunctiva with pigmentation ranging from amelanotic to dark. Diagnosis is typically made through slit lamp examination, visualized by a well circumscribed, variably elevated, variably pigmented, solitary lesion with clear cysts distributed throughout the pigment. In ambiguous cases, anterior segment optical coherence tomography (AS-OCT) can highlight the presence of sub-clinical cysts, whose presence points to a diagnosis of nevus. However, excisional biopsy with histopathology examination is the gold standard for identifying CN.
SUMMARY
CN are benign, variably pigmented lesions. They are the most common of the conjunctival melanocytic tumors. Due to the extremely low risk of transformation to malignant melanoma (MM), CN are usually managed with routine observation and photo documentation.
PubMed: 38390435
DOI: 10.1007/s40135-023-00315-w -
Pigment Cell & Melanoma Research Sep 2023Mucosal melanoma (MM) is a rare subtype of melanoma with an aggressive clinical course. In cutaneous melanoma (CM), the absence of pigmentation and presence of NRAS/KRAS...
Mucosal melanoma (MM) is a rare subtype of melanoma with an aggressive clinical course. In cutaneous melanoma (CM), the absence of pigmentation and presence of NRAS/KRAS mutations are biomarkers indicating an aggressive clinical course with shorter overall survival. Similar data for MM are missing. We present the real-world outcome data in a cohort of genotyped MM patients and assessed the prognostic relevance of pigmentation- and NRAS/KRAS mutation status. We correlated pathological reports and clinical data with overall survival of patients with MM. Furthermore, we performed clinically integrated molecular genotyping and analyzed real world treatment regimens for covariates associated with clinical outcome. We identified 39 patients with available clinical and molecular data. Patients with amelanotic MM had a significantly shorter overall survival (p = .003). In addition, the presence of a NRAS or KRAS mutation was significantly associated with poor overall survival (NRAS or KRAS p = .024). Currently, it is unknown if the same prognostic relevance for the lack of pigmentation and RAS mutations in CM, exists in MM. Here we analyzed a cohort of MM for outcome measures and determined that two known prognostic biomarkers for CM are in fact novel prognosticators for MM.
Topics: Humans; Melanoma; Skin Neoplasms; Prognosis; Proto-Oncogene Proteins p21(ras); Biomarkers; Mutation; Disease Progression; Proto-Oncogene Proteins B-raf; Melanoma, Cutaneous Malignant
PubMed: 37390098
DOI: 10.1111/pcmr.13104 -
Neoplasia (New York, N.Y.) Sep 2023Cutaneous melanoma is the deadliest form of skin neoplasm and its high mortality rates could be averted by early accurate detection. While the detection of melanoma is...
Cutaneous melanoma is the deadliest form of skin neoplasm and its high mortality rates could be averted by early accurate detection. While the detection of melanoma is currently reliant upon melanin visualisation, research into melanosome biogenesis, as a key driver of pathogenesis, has not yielded technology that can reliably distinguish between atypical benign, amelanotic and melanotic lesions. The endosomal-lysosomal system has important regulatory roles in cancer cell biology, including a specific functional role in melanosome biogenesis. Herein, the involvement of the endosomal-lysosomal system in melanoma was examined by pooled secondary analysis of existing gene expression datasets. A set of differentially expressed endosomal-lysosomal genes was identified in melanoma, which were interconnected by biological function. To illustrate the protein expression of the dysregulated genes, immunohistochemistry was performed on samples from patients with cutaneous melanoma to reveal candidate markers. This study demonstrated the dysregulation of Syntenin-1, Sortilin and Rab25 may provide a differentiating feature between cutaneous melanoma and squamous cell carcinoma, while IGF2R may indicate malignant propensity in these skin cancers.
Topics: Humans; Melanoma; Skin Neoplasms; Carcinoma, Squamous Cell; Lysosomes; rab GTP-Binding Proteins; Melanoma, Cutaneous Malignant
PubMed: 37562257
DOI: 10.1016/j.neo.2023.100924 -
BMJ Case Reports Feb 2024
Topics: Humans; Skin Neoplasms; Melanoma, Amelanotic; Neoplasms, Squamous Cell
PubMed: 38395467
DOI: 10.1136/bcr-2023-259515 -
Journal of Personalized Medicine May 2024Acral amelanotic melanomas (AAMs), a rare subset of melanomas located on acral sites such as the palms, soles, and subungual areas, are diagnostically challenging due to... (Review)
Review
BACKGROUND
Acral amelanotic melanomas (AAMs), a rare subset of melanomas located on acral sites such as the palms, soles, and subungual areas, are diagnostically challenging due to their lack of typical pigmentation and often benign clinical appearance. Misdiagnosis is common, leading to delays in treatment and potentially worse outcomes. This systematic review aims to synthesise evidence on cases of AAM initially misdiagnosed as other conditions, to better understand their clinical and epidemiological characteristics, diagnostic pitfalls, and management strategies.
METHODS
A comprehensive search of the MEDLINE/PubMed, EMBASE, and SCOPUS databases was conducted up to March 2024. Case reports and small case series of AAMs initially misdiagnosed as other conditions were included. Data on patient demographics, clinical presentation, and diagnostic methods were collected and analyzed.
RESULTS
Of the 152 records identified, 26 cases from 23 articles met the inclusion criteria. A demographic analysis revealed that the gender distribution appears to be perfectly balanced, with an age range of 38 to 91 years. Misdiagnoses included non-healing ulcers or traumatic lesions (37.5%), benign proliferative lesions (29.2%) and infectious lesions (20.8%). The foot was the most affected site (53.8%). Notably, a histological evaluation was performed in 50% of cases involving the upper extremities, in contrast to only 7.1% of cases involving the foot and 0% of cases of the heel. This discrepancy suggests a reluctance to perform biopsies in the lower extremities, which may contribute to a higher misdiagnosis rate in these areas.
CONCLUSIONS
The underutilization of biopsy in the diagnosis of lower extremity lesions contributes significantly to the misdiagnosis and delay in treatment of AAMs. Especially when the clinical assessment and dermoscopy are inconclusive, biopsies of suspicious lesions are essential. Immunohistochemistry and markers such as PRAME are critical in differentiating melanoma from other malignancies such as clear cell sarcoma. This review highlights the need for increased vigilance and a proactive diagnostic approach to increase early detection rates and improve prognostic outcomes.
PubMed: 38793100
DOI: 10.3390/jpm14050518 -
Journal of the American Academy of... Feb 2024Dermoscopic and reflectance confocal microscopy (RCM) correlations between morphologic groups of melanoma have not yet been described.
BACKGROUND
Dermoscopic and reflectance confocal microscopy (RCM) correlations between morphologic groups of melanoma have not yet been described.
OBJECTIVE
Describe and compare dermoscopic and RCM features of cutaneous melanomas with histopathological confirmation.
METHODS
Single center, retrospective analysis of consecutive melanomas evaluated with RCM (2015-2019). Lesions were clinically classified as typical, nevus-like, amelanotic/nonmelanoma skin cancer (NMSC)-like, seborrheic keratosis (SK)-like and lentigo/lentigo maligna (LM)-like. Presence or absence of common facial and nonfacial melanoma dermoscopic and RCM patterns were recorded. Clusters were compared with typical lesions by multivariate logistic regression.
RESULTS
Among 583 melanoma lesions, significant differences between clusters were evident (compared to typical lesions). Observation of dermoscopic features (>50% of lesions) in amelanotic/NMSC-like lesions consistently displayed 3 patterns (atypical network, atypical vascular pattern + regression structures), and nevus-like and SK-like lesions and lentigo/LM-like lesions consistently displayed 2 patterns (atypical network + regression structures, and nonevident follicles + heavy pigmentation intensity). Differences were less evident with RCM, as almost all lesions were consistent with melanoma diagnosis.
LIMITATIONS
Small SK-like lesions sample, single RCM analyses (no reproduction of outcome).
CONCLUSION
RCM has the potential to augment our ability to consistently and accurately diagnose melanoma independently of clinical and dermoscopic features.
Topics: Humans; Melanoma; Dermoscopy; Retrospective Studies; Skin Neoplasms; Hutchinson's Melanotic Freckle; Keratosis, Seborrheic; Nevus; Nevus, Pigmented; Lentigo; Microscopy, Confocal; Diagnosis, Differential
PubMed: 37988042
DOI: 10.1016/j.jaad.2023.09.084 -
Cureus Jul 2023Amelanotic malignant melanoma (AMM) is a skin cancer that arises from mutated melanocytes that lack pigmentation. AMM represents 2-8% of all malignant melanomas. This...
Amelanotic malignant melanoma (AMM) is a skin cancer that arises from mutated melanocytes that lack pigmentation. AMM represents 2-8% of all malignant melanomas. This rare subtype is difficult to diagnose clinically as it mimics other benign skin lesions. AMM can occur in any part of the body with various presentations and has a predilection for male gender and fair skin tones. We present a case report of a 62-year-old Caucasian male with AMM of the right lower extremity. The patient presented with a painless nodule on his right lower extremity that rapidly increased in size for seven months with no signs of malignancy, such as fever, night sweats, fatigue, bruising, weight loss, or headache. Simultaneously, the patient presented with right inguinal lymphadenopathy and pitting edema of the right lower extremity. The patient had a previous medical history of basal and squamous cell carcinoma and psoriasis with no personal or family history of melanoma. The mass was excised and sent to a pathologist along with a right inguinal sentinel lymph node biopsy. The final pathology report revealed an ulcerated AMM on the right lower extremity and a positive node for melanoma with a metastatic deposit. The patient underwent adjuvant immunotherapy resulting in the clearance of the cancer cells. This report highlights the importance of early diagnosis, appropriate surgical management, and adjuvant therapy to improve the prognosis of this rare melanoma subtype.
PubMed: 37575793
DOI: 10.7759/cureus.41665 -
Veterinary Pathology Apr 2024Histologic diagnosis of less well-differentiated cases of canine extramedullary plasmacytomas (CEMPs) may require immunohistochemical confirmation to discriminate these...
Histologic diagnosis of less well-differentiated cases of canine extramedullary plasmacytomas (CEMPs) may require immunohistochemical confirmation to discriminate these tumors from other round cells tumors including lymphoma, cutaneous histiocytoma, and amelanotic melanomas. CEMPs are characterized by widespread immunoreactivity for multiple myeloma 1 (MUM1) antigen and λ light chains, while the melanocytic marker melan-A has been reported to yield negative results. Here, 33 randomly selected CEMPs, 20 melanocytomas, and 20 malignant melanomas were immunohistochemically tested for MUM1, melan-A, and PNL2. In addition, CEMPs were examined for PAX5, E-cadherin, CD3, CD18, CD20, S100, as well as λ and κ light chain immunoreactivity. All CEMPs were characterized by labeling for MUM1 and λ light chain, as well as variable immunopositivity for the remaining antibodies. Notably, 13 cases of CEMPs (39.4%) exhibited immunolabeling for melan-A. Melanocytic tumors immunolabeled for melan-A (40/40; 100%) and PNL2 (34/40; 85%). An unexpected cytoplasmic immunoreactivity for MUM1 was observed in 2 melanocytic tumors. Summarized, MUM1 or melan-A immunomarkers alone are not sufficient to differentiate between CEMPs and amelanotic melanomas and should be part of a larger immunopanel including λ light chain, CD20, and PNL2.
PubMed: 38642035
DOI: 10.1177/03009858241246979