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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 -
Anais Brasileiros de Dermatologia 2019
Topics: Erythema; Humans; Immunohistochemistry; Male; Melanoma, Amelanotic; Melanoma-Specific Antigens; Middle Aged; Skin Neoplasms; gp100 Melanoma Antigen
PubMed: 31644637
DOI: 10.1590/abd1806-4841.20198453 -
Actas Dermo-sifiliograficas Jan 2022Desmoplastic melanoma (DM) accounts for 0.4% to 4% of all melanomas. These skin tumors are mainly formed by amelanotic spindled melanocytes immersed in an abundant... (Review)
Review
Desmoplastic melanoma (DM) accounts for 0.4% to 4% of all melanomas. These skin tumors are mainly formed by amelanotic spindled melanocytes immersed in an abundant collagen stroma and are classified as pure when the desmoplastic component accounts for at least 90% of the invasive tumor and as mixed or combined otherwise. DMs are more common in men (male to female ratio, 1.7 to 2:1), and the mean age at diagnosis is 66 to 69 years. The tumors tend to occur in chronically sun-exposed areas, often in association with lentigo maligna, and are difficult to recognize because they can resemble a scar, presenting as a firm, unpigmented papule or plaque with poorly defined borders. DMs also have a strong tendency to recur locally, and pure variants rarely spread to the lymph nodes. Nonetheless, recently published series suggest that patients with DM have a similar prognosis to those with nondesmoplastic melanoma of the same thickness. The clinical management of DM varies in certain aspects from that of other melanomas and is reviewed in this article.
PubMed: 35249710
DOI: 10.1016/j.ad.2021.06.004 -
Annals of Ibadan Postgraduate Medicine Jun 2012Malignant melanomas of the mucosal regions of the head and neck are extremely rare neoplasms accounting for less than 1% of all melanomas. Approximately half of all head...
Malignant melanomas of the mucosal regions of the head and neck are extremely rare neoplasms accounting for less than 1% of all melanomas. Approximately half of all head and neck melanomas occur in the oral cavity. Less than 2% of all melanomas lack pigmentation, in the oral mucosa however, up to 75% of cases are amelanotic. No etiologic factors or risk factors have been recognized for oral melanomas. Some authors have suggested that oral habits and selfmedication may be of etiological significance. Oral melanoma is rare but it is relatively frequent in countries like Japan, Uganda, and India. It is rarely identified under the age of 20 years. In Australia where cutaneous melanomas are relatively common primary melanoma of the oral mucosa is rare. The surface architecture of oral melanomas ranges from macular to ulcerated and nodular. The lesion is said to be asymptomatic in the early stages but may become ulcerated and painful in advanced lesions. The diagnosis of amelanotic melanoma is more difficult than that of pigmented lesions. The neoplasm consists of spindle-shaped cells with many mitotic figures and no cytoplasmic melanin pigmentation. Immunohistochemistry using S-100, HMB-45, Melan-A and MART-1 will help in establishing the correct diagnosis. Radical surgery with ample margins and adjuvant chemotherapy are appropriate management protocol for malignant melanoma. Oral melanoma is associated with poor prognosis but its amelanotic variant has even worse prognosis because it exhibits a more aggressive biology and because of difficulty in diagnosis which leads to delayed treatment.
PubMed: 25161399
DOI: No ID Found -
Survey of Ophthalmology 2020Intraocular leiomyoma is a benign smooth muscle tumor. First recognized before the era of immunohistochemistry, uveal leiomyomas have been described in case reports and... (Review)
Review
Intraocular leiomyoma is a benign smooth muscle tumor. First recognized before the era of immunohistochemistry, uveal leiomyomas have been described in case reports and small case series. We add 3 new cases, for a total of 80. Of these, there were 29 men and 51 women. The mean and median ages were 35.8 and 30.5 years respectively, with a range of 8 to 80 years. Curiously, ciliary body tumors were more common in females, whereas iris and posterior choroidal leiomyomas were more prevalent in males. Infrequently associated with systemic fibroids, nuclear expression of sex steroid receptors was inconsistent. Iris and posterior choroidal leiomyoma were predominantly amelanotic, while 40% of ciliary body leiomyomas were brown. Two-thirds of the leiomyomas blocked transillumination partially or completely, a feature shared by uveal melanoma. In general, low-frequency ultrasound imaging reveals low to moderate internal reflectivity; however, high-frequency anterior uveal ultrasound was used to localize a leiomyoma as resident in the suprachoroidal space with an overlying layer of intact choroid. In the few cases examined by physiologic imaging, increased metabolic activity (typically associated with malignancy and inflammation) has been noted. We found that pigmented uveal leiomyomas can be clinically identical to melanoma. Therefore, histopathology with immunohistochemical staining for smooth muscle actin was the most reliable diagnostic method to differentiate pigmented uveal leiomyoma from melanoma. Treatment is governed by the clinical diagnosis, tumor size and location, as well as prognosis for vision and globe preservation.
Topics: Adult; Eye Neoplasms; Female; Humans; Leiomyoma; Male; Middle Aged; Uvea
PubMed: 31923479
DOI: 10.1016/j.survophthal.2019.12.008 -
Journal of Laboratory Physicians Jun 2023Malignant melanoma is an aggressive, notorious tumor showing great variability in morphological and immunohistochemical expression, thus commonly leading to an erroneous...
Malignant melanoma is an aggressive, notorious tumor showing great variability in morphological and immunohistochemical expression, thus commonly leading to an erroneous diagnosis. Within the melanoma group, amelanotic melanoma, with its wide clinical presentations, lack of pigmentation, and varied histological appearances, has taken on a new persona as a master masquerader. Use of immunohistochemistry in the diagnosis of malignant tumors, including melanoma, is primordial and indispensable. However, the problem gets compounded in scenario of aberrant antigenic expression. The present case posed multiple diagnostic challenges in form of atypical clinical presentation, variant morphology, as well as aberrant antigenic expression. Here, we present the case of a 72-year-old male who, upon his initial presentation, was thought to be sarcomatoid anaplastic plasmacytoma, but 5 months later another biopsy from a different site revealed the actual diagnosis of amelanotic melanoma.
PubMed: 37323600
DOI: 10.1055/s-0042-1757236 -
Head and Neck Pathology Jun 2022Oral amelanotic melanoma (OAM) is a rare, non-pigmented mucosal neoplasm representing less than 2% of all melanoma. The present study analyses the available data on OAM... (Review)
Review
Oral amelanotic melanoma (OAM) is a rare, non-pigmented mucosal neoplasm representing less than 2% of all melanoma. The present study analyses the available data on OAM and describes its clinicopathological features, identifying potential prognostic factors. Online electronic databases such as PubMed-Medline, Embase, and Scopus were searched using appropriate keywords from the earliest available date till 31st March 2021 without restriction on language. Additional sources like Google Scholar, major journals, unpublished studies, conference proceedings, and cross-references were explored. 37 publications were included for quantitative synthesis, comprising 55 cases. The mean age of the patients was 59.56 years, and the lesions were more prevalent in males than in females. OAM's were most prevalent in the maxilla (67.2%) with ulceration, pinkish-red color, nodular mass, and pain. 2 patients (3.36%) were alive at their last follow-up, and 25 were dead (45.4%). Univariate survival analysis of clinical variables revealed that age older than 68 years (p = 0.003), mandibular gingiva (p = 0.007), round cells (p = 0.004), and surgical excision along with chemotherapy & radiation therapy (p = 0.001) were significantly associated with a lower survival rate. Oral Amelanotic Melanoma is a neoplasm with a poor prognosis, presenting a 6.25% possibility of survival after 5 years. Patients older than 68 years, lesions in the mandibular gingiva, round cells, and surgical excision along with chemotherapy and radiotherapy, presented the worst prognosis. However, they did not represent independent prognostic determinants for these patients.
Topics: Aged; Female; Humans; Male; Melanoma; Melanoma, Amelanotic; Middle Aged; Prognosis; Skin Neoplasms; Survival Rate; Melanoma, Cutaneous Malignant
PubMed: 34309791
DOI: 10.1007/s12105-021-01366-w -
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