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Chonnam Medical Journal Sep 2016Malignant melanoma is a rare disease in Asians but potentially the most aggressive form of skin cancer worldwide. It can occur in any melanocyte-containing anatomic... (Review)
Review
Malignant melanoma is a rare disease in Asians but potentially the most aggressive form of skin cancer worldwide. It can occur in any melanocyte-containing anatomic site. Four main cutaneous melanoma subtypes are recognized: lentigo maligna melanoma, superficial spreading melanoma, acral lentiginous melanoma (ALM), and nodular melanoma. Generally, excessive exposure to ultraviolet (UV) radiation increases the risk of melanoma. The exception is ALM, which is the most common melanoma subtype in Asians and is not associated with UV radiation. ALM presents as dark brownish to black, irregular maculopatches, nodules, or ulcers on the palms, soles, and nails. The lesions may be misdiagnosed as more benign lesions, such as warts, ulcers, hematomas, foreign bodies, or fungal infections, especially in amelanotic acral melanomas where black pigments are absent. The aim of this brief review is to improve understanding and the rate of early detection thereby reducing mortality, especially regarding cutaneous melanoma in Asians.
PubMed: 27689028
DOI: 10.4068/cmj.2016.52.3.185 -
Medicina 2020Desmoplastic melanoma is a rare presentation of melanoma with a different clinical behavior compared to other histological variants. Its diagnosis in early stages is a...
Desmoplastic melanoma is a rare presentation of melanoma with a different clinical behavior compared to other histological variants. Its diagnosis in early stages is a challenge due to its variable clinical presentation, with a predominant dermal component and the frequent absence of pigment. Its histology is divided into pure and mixed type, and this classification has important prognostic implications. The average Breslow thickness at diagnosis is higher than in other melanoma variants. However, the tendency to lymph node metastasis is low.
Topics: Aged; Biopsy; Diagnosis, Differential; Female; Humans; Male; Melanoma; Middle Aged; Skin Neoplasms
PubMed: 32442943
DOI: No ID Found -
International Journal of Dermatology Mar 2021Amelanotic melanoma is an extremely rare subtype of cutaneous melanoma. The tumor characteristics are still not well understood, especially for those located in the head...
BACKGROUND
Amelanotic melanoma is an extremely rare subtype of cutaneous melanoma. The tumor characteristics are still not well understood, especially for those located in the head and neck.
METHODS
Tumor characteristics of patients diagnosed with amelanotic melanoma of the head and neck (AMHN) from January 1, 2004, to December 31, 2015, were analyzed by querying the National Cancer Database. Characteristics of AMHN were subsequently compared with common malignant melanoma of the head and neck (CMMHN).
RESULTS
Three hundred and sixty-eight patients were diagnosed with AMHN, and 69,267 were diagnosed with CMMHN. Of those with AMHN, 128 (34.8%) had melanoma located on the scalp and neck, and 172 (46.7%) were diagnosed with an early disease stage (i.e., 0, I, or II). When compared with CMMHN, patients with AMHN were more likely to be diagnosed after 80 years of age (25.3% vs. 18.2%; odds ratio [OR], 3.28; 95% CI, 1.09-9.84; P = 0.03), when Breslow depth was between 2.01 and 4.00 mm (28.5% vs. 6.5%; OR, 1.92; 95% CI, 1.15-3.19; P = 0.01), when ulceration was present (36.7% vs. 9.0%; OR, 1.99; 95% CI, 1.34-2.97; P = 0.001), and when mitotic count was 1 or more/mm (40.5% vs. 12.8%; OR; 2.53; 95% CI, 1.09-5.89; P = 0.03). No statistical difference was found for sex, specific location, stage, or lymph node involvement.
CONCLUSION
Our study determined that AMHN is associated with older age, increased Breslow depth, presence of ulceration, and greater mitotic count when compared with CMMHN.
Topics: Aged; Databases, Factual; Head and Neck Neoplasms; Humans; Melanoma, Amelanotic; Prognosis; Retrospective Studies; Scalp; Skin Neoplasms
PubMed: 33040374
DOI: 10.1111/ijd.15243 -
Journal of Drugs in Dermatology : JDD Nov 2017
Amelanotic melanoma (AM) is one of the great masqueraders in dermatology. It is a very difficult clinical diagnosis to make because these tumors are devoid of pigment... (Review)
Review
Amelanotic melanoma (AM) is one of the great masqueraders in dermatology. It is a very difficult clinical diagnosis to make because these tumors are devoid of pigment and other clues of melanoma. They are commonly misdiagnosed clinically as other benign and malignant conditions. We present a new case of AM in an 84-year-old woman with a history of non-melanoma skin cancer. She had a thin pink plaque that was initially misdiagnosed as a basal cell carcinoma. We also discuss dermoscopy and its valuable role to improve diagnostic accuracy. A review of dermoscopic features that favor and oppose the clinical diagnosis of AM is discussed. Even with dermoscopy, it is still important to have a high index of suspicion and a low threshold to biopsy when the clinical diagnosis is unclear.
J Drugs Dermatol. 2017;16(11):1164-1165.
.Topics: Aged, 80 and over; Dermoscopy; Diagnosis, Differential; Female; Humans; Melanoma, Amelanotic; Skin Neoplasms
PubMed: 29141067
DOI: No ID Found -
Acta Dermato-venereologica Mar 2020Amelanotic melanoma (AM) is a rare subtype of cutaneous melanoma that lacks melanin pigment. Clinical diagnosis of AM is challenging because it may mimic benign or...
Amelanotic melanoma (AM) is a rare subtype of cutaneous melanoma that lacks melanin pigment. Clinical diagnosis of AM is challenging because it may mimic benign or malignant melanocytic and non-melanocytic neoplasms and inflammatory skin diseases. Completely amelanotic melanomas are rare, but approximately 2-8% of all melanomas lack pigment or are sparsely pigmented (1, 2). AM often present a particular diagnostic challenge due to their inconspicuous appearance and lack of the classical, well-recognized characteristics and clues found in pigmented lesions (3). In particular, when concealed by an inflammatory dermatosis, such as psoriasis, AM can remain undiagnosed for a long time (4). We describe here, to our knowledge, the first case of AM concealed by psoriasis.
Topics: Adult; Dermatologic Agents; Dermoscopy; Female; Humans; Melanoma, Amelanotic; Methotrexate; Psoriasis; Skin Neoplasms
PubMed: 31930427
DOI: 10.2340/00015555-3397 -
Cureus Jul 2022Acral amelanotic melanoma can be difficult to diagnose and is often clinically aggressive. The present report describes a case of an acral amelanotic melanoma presenting...
Acral amelanotic melanoma can be difficult to diagnose and is often clinically aggressive. The present report describes a case of an acral amelanotic melanoma presenting as a non-healing wound after mimicking a plantar wart for two years. The decision to biopsy a borderline-suspicious lesion on the lower extremity in an elderly individual must be weighed carefully, as lower extremity biopsy carries a risk of poor wound healing and other complications. We discuss clinical and epidemiologic features that can assist in deciding when to perform a biopsy in this setting and can improve the early detection of acral amelanotic melanoma.
PubMed: 35936139
DOI: 10.7759/cureus.26615 -
Journal of the European Academy of... Feb 2023Amelanotic/hypomelanotic lentigo maligna and lentigo maligna melanoma (AHLM/LMM) may be very difficult to diagnose at an early stage.
BACKGROUND
Amelanotic/hypomelanotic lentigo maligna and lentigo maligna melanoma (AHLM/LMM) may be very difficult to diagnose at an early stage.
OBJECTIVES
To quantify the predictive value of dermoscopic and reflectance confocal microscopy (RCM) features for AHLM/LMM.
METHODS
Dermoscopic and RCM images of histopathologically diagnosed AHLM/LMM, amelanotic/hypomelanotic benign lesions (AHBL), and amelanotic/hypomelanotic basal and squamous cell carcinomas (AHBCC/AHSCC) of the head and neck from consecutive patients were retrospectively collected and blindly evaluated by three observers to assess presence or absence of dermoscopic and RCM criteria.
RESULTS
Overall, 224 lesions in 216 patients including LM/LMM (n = 55, 24.6%), AHBL (n = 107, 47.8%) and AHBCC/AHSCC (n = 62, 27.7%) were analysed. Multivariable analysis showed that milky-red areas (OR = 5.46; 95% CI: 1.51-19.75), peripheral light brown structureless areas (OR = 19.10; 4.45-81.96), linear irregular vessels (OR = 5.44; 1.45-20.40), and asymmetric pigmented follicles (OR = 14.45; 2.77-75.44) at dermoscopy, and ≥3 atypical cells in five fields (OR = 10.12; 3.00-34.12) and focal follicular localization of atypical cells at dermo-epidermal junction (DEJ) (OR = 10.48; 1.10-99.81) at RCM were significantly independent diagnostic factors for AHLM/LMM vs. AHBL. In comparison with AHBCC/AHSCC, peripheral light brown structureless area (OR = 7.11; 1.53-32.96), pseudonetwork around hair follicles (OR = 16.69; 2.73-102.07), and annular granular structures (OR = 42.36; 3.51-511.16) at dermoscopy and large dendritic (OR = 6.86; 3.15-38.28) and round pagetoid cells (OR = 26.78; 3.15-227.98) at RCM led to a significantly increased risk of diagnosing AHLM/LMM.
CONCLUSIONS
Amelanotic/hypomelanotic lentigo maligna and lentigo maligna melanoma may have the same dermoscopic features of AHM on other body sites, such as milky red areas, peripheral light brown structureless areas and linear irregular vessels. These features, asymmetric pigmented follicles and at RCM ≥ 3 atypical cells in five fields and focal follicular extension of atypical cells at DEJ may help in recognizing AHLM/LMM even when LM conventional features (e.g., obliteration of hair follicles under dermoscopy and large pagetoid cells under RCM) are absent or present only in very small areas of the lesion.
Topics: Humans; Hutchinson's Melanotic Freckle; Skin Neoplasms; Retrospective Studies; Diagnosis, Differential; Microscopy, Confocal; Dermoscopy
PubMed: 36196781
DOI: 10.1111/jdv.18636 -
JAMA Ophthalmology Jan 2016
Topics: Biomarkers, Tumor; Conjunctival Neoplasms; Cryotherapy; Diabetic Retinopathy; Glaucoma, Open-Angle; Humans; Hypertension; MART-1 Antigen; Male; Melanoma, Amelanotic; Middle Aged; Ophthalmologic Surgical Procedures; S100 Proteins
PubMed: 26767731
DOI: 10.1001/jamaophthalmol.2015.3568 -
Protoplasma Sep 2021The biology of three amelanotic melanoma cell lines (Ab, B16F10, and A375) of different species origin was analyzed during in vitro induced melanization in these cells....
The biology of three amelanotic melanoma cell lines (Ab, B16F10, and A375) of different species origin was analyzed during in vitro induced melanization in these cells. Melanin production was induced by DMEM medium characterized by a high level of L-tyrosine (a basic amino acid for melanogenesis). The biodiversity of amelanotic melanoma cells was confirmed by their different responses to melanogenesis induction; Ab hamster melanomas underwent intensive melanization, mouse B16F10 darkened slightly, while human A375 cells did not show any change in melanin content. Highly melanized Ab cells entered a cell death pathway, while slight melanization did not influence cell biology in a significant way. The rapid and high melanization of Ab cells induced apoptosis documented by phosphatidylserine externalization, caspase activation, and mitochondrial energetic state decrease. Melanoma cell type, culture medium, and time of incubation should be taken into consideration during amelanotic melanoma cell culture in vitro. L-tyrosine, as a concentration-dependent factor presented in the culture media, could stimulate some amelanotic melanoma cell lines (Ab, B16F10) to melanin production. The presence of melanin should be considered in the examination of antimelanoma compounds in vitro, because induction of melanin may interfere or be helpful in the treatment of amelanotic melanoma.
Topics: Animals; Apoptosis; Cell Line; Cricetinae; Melanins; Melanoma, Amelanotic; Mice; Skin Neoplasms
PubMed: 33506271
DOI: 10.1007/s00709-021-01613-5 -
The British Journal of Dermatology Aug 2020Dermoscopy and reflectance confocal microscopy (RCM) are noninvasive techniques for the diagnosis of skin lesions. Their accuracy for amelanotic/hypomelanotic melanoma... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Dermoscopy and reflectance confocal microscopy (RCM) are noninvasive techniques for the diagnosis of skin lesions. Their accuracy for amelanotic/hypomelanotic melanoma (AHM) has not been systematically studied.
OBJECTIVES
We aimed to investigate systematically the accuracy of dermoscopy and RCM and to compare the accuracy between them for diagnosing AHM.
METHODS
We searched the PubMed, Web of Science, Embase and Cochrane Library databases for eligible studies about dermoscopy, RCM and AHM from inception to 31 June 2019. The quality of the studies was assessed with the Quality Assessment of Diagnostic Accuracy Studies tool. The pooled results were calculated using a random effects model in Stata 14, Meta-DiSc, RevMan 5·3 and SAS 9·4. We also explored the sources of heterogeneity by sensitivity analysis.
RESULTS
Seven studies with a total of 1111 lesions were included. The pooled sensitivity and specificity of dermoscopy for the diagnosis of AHM were 61% [95% confidence interval (CI) 0·37-0·81] and 90% (95% CI 0·74-0·97), respectively. The corresponding respective values of RCM for the diagnosis of AHM were 67% (95% CI 0·51-0·81) and 89% (95% CI 0·86-0·92). In three studies including the performance of both RCM and dermoscopy, the relative diagnostic odds ratio of RCM over dermoscopy was 4·69 (95% CI 0·81-27·3) (P = 0·068).
CONCLUSIONS
Our study demonstrates that both dermoscopy and RCM offer good diagnostic accuracy with high specificity and moderate sensitivity in the diagnosis of AHM. RCM is more accurate than dermoscopy in diagnosing AHM but the comparison needs to be confirmed. What's already known about this topic? Amelanotic/hypomelanotic melanoma (AHM) is the most lethal skin cancer. The diagnosis of AHM is a great challenge because of its nonspecific clinical manifestation. Early diagnosis can improve the prognosis. Dermoscopy and reflectance confocal microscopy (RCM) have high diagnostic accuracy for pigmented melanoma. What does this study add? Both dermoscopy and RCM offer good diagnostic accuracy with high specificity and moderate sensitivity for AHM. RCM might be more accurate than dermoscopy for diagnosis of AHM. More research on the diagnostic accuracy of dermoscopy and RCM for AHM is required in support of these findings.
Topics: Dermoscopy; Humans; Hypopigmentation; Melanoma, Amelanotic; Microscopy, Confocal; Sensitivity and Specificity; Skin Neoplasms
PubMed: 31747045
DOI: 10.1111/bjd.18722