Department of Dermatology, University Hospital of Saint Etienne, Saint Etienne, France.
Department of Medical, Surgical and Neurological Science, Dermatology Section, University of Siena, S. Maria alle Scotte Hospital, Siena, Italy.
J Eur Acad Dermatol Venereol. 2017 Nov;31(11):1834-1840. doi: 10.1111/jdv.14353. Epub 2017 Jun 14.
Mucosal melanomas are rare and highly aggressive tumours. Few studies evaluated mucosal melanomas of locations other than the head and neck region, and other than those of the Asian population.
The objective of this study was to analyse the clinical and histological features, as well as the mutational status of c-kit and b-raf gene of mucosal melanoma in any localization in a French series.
We investigated clinical (sex, age, performance status, survival, treatment of the patients and lack of pigmentation of the tumours) and histopathological features (ulceration, Breslow's index, mitotic rate), as well as the mutational status of c-kit and b-raf of 86 mucosal melanomas diagnosed in 15 years in four French University Hospitals.
Most melanomas affected women (72%) and the genital region (46.5%). A fifth of melanomas were amelanotic. 81% of melanomas had a Breslow's index ≥1, whereas all glans melanomas, and most vulvar melanomas had a Breslow index ≤1 mm. Overall survival was 54% at 3 years; 11.6% of the 43 tested mucosal melanomas were c-kit-mutated while the 15 tested genital melanomas were not. The c-kit gene mutation did not influence the overall survival. Age ≥ 50, amelanotic type and performance status ≥1 were not poor prognostic factors in our series.
This study confirmed that mucosal melanomas are rare and could be difficult to diagnose being often amelanotic and in hidden sites. Most melanomas were thick at the diagnosis, but glans and vulvar melanomas were thinner probably because of their greater visibility. The frequency of the c-kit mutation varied depending on the initial tumour site. In our series, the prognosis was poor, independently from c-kit mutations and the patient's general health and age. The presence of metastasis at diagnosis was associated with a worse prognosis indicating the importance of an early diagnosis.
黏膜黑色素瘤是罕见且侵袭性很强的肿瘤。只有少数研究评估了头颈部以外和非亚洲人群的其他部位的黏膜黑色素瘤。
本研究旨在分析位于任何部位的黏膜黑色素瘤的临床和组织学特征，以及 c-kit 和 b-raf 基因突变状态。
我们调查了 86 例在法国四家大学医院诊断的 15 年间黏膜黑色素瘤患者的临床（性别、年龄、表现状态、生存情况、治疗和肿瘤的色素缺失）和组织病理学特征（溃疡、Breslow 指数、有丝分裂率），以及 c-kit 和 b-raf 的基因突变状态。
大多数黑色素瘤影响女性（72%）和生殖器部位（46.5%）。1/5 的黑色素瘤无色素沉着。81%的黑色素瘤的 Breslow 指数≥1，而所有龟头黑色素瘤和大多数外阴黑色素瘤的 Breslow 指数≤1mm。3 年总生存率为 54%；在 43 例检测的黏膜黑色素瘤中，有 11.6%发生 c-kit 突变，而 15 例检测的生殖器黑色素瘤未发生突变。c-kit 基因突变并不影响总生存率。在我们的研究中，年龄≥50 岁、无色素沉着型和表现状态≥1 并不是不良预后因素。
本研究证实，黏膜黑色素瘤罕见，且常为无色素沉着和隐匿性病变，诊断困难。大多数黑色素瘤在诊断时已经很厚，但龟头和外阴黑色素瘤较薄，可能是因为它们更容易被发现。c-kit 基因突变的频率取决于初始肿瘤部位。在我们的研究中，预后较差，与 c-kit 突变和患者的一般健康状况和年龄无关。诊断时出现转移与预后较差相关，这表明早期诊断的重要性。
