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Adult Ocular and Orbital (Ocular Adnexa) Tumors
Published in Pat Price, Karol Sikora, Treatment of Cancer, 2020
P.N. Plowman, Rachel Lewis, J.L. Hungerford
Malignant melanocytic tumors are mostly melanomas. Their management is largely surgical. Malignant melanoma of the eyelid skin is extremely rare and is best managed by wide surgical excision. Malignant melanoma is more common in the conjunctiva (Figure 2.6), but nevertheless it is still rare. The majority of conjunctival melanomas arise in a pre-existing conjunctival lesion. Approximately 18% of tumors arise in a pre-existing nevus and 57% in primary acquired melanosis (PAM). PAM was formerly termed pre-cancerous melanosis and may be a manifestation of the atypical mole syndrome. Atypical melanocytes spread to involve much of the conjunctiva and on to the cornea and eyelid.24–26 Ultimately, melanoma develops in most cases of PAM in which atypia are found, as indicated by biopsy or impression cytology,27 and in most cases multifocal tumors develop sequentially.
Atypical Spitz nevus (tumor)
Published in Longo Caterina, Diagnosing the Less Common Skin Tumors, 2019
In 1989, Smith and colleagues2 described the “Spitz nevus with atypia and metastasis.” A few years later, Barnhill et al.3,4 defined the category of metastasizing Spitz tumor, or atypical Spitz tumor. Recently, these lesions have been included in the group of melanocytic tumors of uncertain malignant potential.11,12 Currently there are three interpretations regarding the taxonomy of ASTs: they are nevi that have features in common with melanoma but are biologically benign,they are intermediates between nevi and melanomas,they represent a subset of melanomas with a better prognosis than conventional melanomas.13
Melanocytic Tumors
Published in Dongyou Liu, Tumors and Cancers, 2017
Melanocytic tumors of the CNS demonstrate overlapping histological characteristics but show distinct biological behavior. Melanocytomas harbor GNAQ/11 mutations and copy number variants (CNVs) involving chromosomes 3 and 6, whereas melanomas frequently contain mutation in the TERT promoter and additional oncogene mutations, together with recurrent chromosomal losses involving chromosomes 9, 10, and 6q, as well as gains of 22q. In contrast, melanotic schwannomas possess a complex karyotype with recurrent monosomy of chromosome 22q and variable whole chromosomal gains and recurrent losses commonly involving chromosomes 1, 17p, and 21, in addition to mutations in the BRAF V600 or KIT genes. Like uveal melanoma, primary leptomeningeal melanocytic neoplasms appear to have oncogenic mutations in GNAQ and GNA11 but not in BRAF, NRAS, and HRAS. Oncogenic mutations in primary melanocytic tumors are remarkably different between adult patients (e.g., GNAQ, GNA11) and children (e.g., NRAS) [7].
Deep learning-based fully automated diagnosis of melanocytic lesions by using whole slide images
Published in Journal of Dermatological Treatment, 2022
Yongyang Bao, Jiayi Zhang, Xingyu Zhao, Henghua Zhou, Ying Chen, Junming Jian, Tianlei Shi, Xin Gao
According to the “Melanocytic Tumors” section of the 4th edition of the WHO Classification of Skin Tumors, 668 patients diagnosed with benign, atypical (atypical Spitzoid neoplasms, melanocytoma, and nevus with atypia), or malignant (melanoma of the skin, mucosa, extremity, and choroidal membrane) melanocytic lesions between 2001 and 2018 at Shanghai Ninth People’s Hospital, Shanghai JiaoTong University School of Medicine, were included in this study, and 927 H&E-stained sections from these patients were collected. To develop and evaluate the DL-based fully automated diagnostic method, the patients were randomly divided into training and testing (internal testing) sets. To further evaluate the generalization capacity of the DL-based fully automated diagnostic method, another 54 H&E-stained sections from 43 patients with melanocytic lesions were collected from the North Campus of Shanghai Ninth People’s Hospital, Shanghai JiaoTong University School of Medicine and Baoshan Branch of Shanghai First People’s Hospital, as an independent subgroup used for testing (the external testing set). All H&E-stained sections were digitalized as WSIs by using a NanoZoomer S60 digital slide scanner (Hamamatsu) with 40× magnification.
Noninvasive imaging for the diagnosis of melanocytic conjunctival tumor
Published in Expert Review of Ophthalmology, 2020
Elisa Cinotti, Marco Campoli, Damien Grivet, Jean Luc Perrot, Pietro Rubegni
Nevi are benign melanocytic tumors characterized by melanocyte proliferation at the junction between the epithelium and the substantia propria (junctional nevi), in the substantia propria or both (compound nevi). Nevi can be clinically flat or raised, amelanotic or pigmented (Figure 2(a,d)). At dermoscopy, we found that the pigmentation was mainly structureless or distributed in dots and/or globules in a series of 69 nevi (Figure 2(b,c,e)) [21]. In rare cases, the pigmentation formed circles. All nevi had a brown pigmentation; gray, blue, black and white colors were also visible in isolated cases [21]. In 40% of cases, clear cysts were visible suggesting epithelial cystic nevi (Figure 2(e)) [21]. Notably, dermoscopy helped to identify the cysts of minor size not visible under the naked eye [21]. Differently from MMs and PAMs, nevi showed globules in half of the cases in addition to dots and structureless pigmentation; this aspect could be related to the presence of well-defined roundish melanocytic nests [21]. Moreover, we could find a lower presence of gray color in nevi than MMs [21].
Primary sellar melanocytoma: report of two cases treated at the same institution and their long-term outcome
Published in British Journal of Neurosurgery, 2023
Luigi Albano, Marco Losa, Giorgio Spatola, Pietro Panni, Maria Rosa Terreni, Lina Raffaella Barzaghi, Pietro Mortini
Sublabial transsphenoidal microsurgery was performed at our Institute (April 2003). A gross total tumor resection was obtained. There was no macroscopic tumor invasion of the adjacent bone, dura, or diaphragma sellae. Histology was of a melanocytic tumor.