School of Medicine, Universidad Católica de Valencia San Vicente Mártir, València, Spain.
Department of Dermatology, Instituto Valenciano de Oncología, València, Spain.
JAMA Dermatol. 2019 Jul 1;155(7):782-788. doi: 10.1001/jamadermatol.2019.0467.
Lentigo maligna (LM) presents an invasive component in up to 20% of biopsied cases, but to date the histologic features useful in detecting this invasive component have not been described. Some histologic characteristics are hypothesized to contribute to the progression of LM invasion.
To identify the histologic characteristics associated with lentigo maligna melanoma (LMM) in patients with LM diagnosed by a partial diagnostic biopsy.
DESIGN, SETTING, AND PARTICIPANTS: A retrospective cross-sectional study of patients treated between January 1, 2000, and December 31, 2017, was conducted in a referral oncology center in València, Spain. Data and specimens of patients (n = 96) with a diagnosis of primary cutaneous melanoma in the form of either LM or LMM who had undergone surgical treatment, a complete histologic examination of the whole tumor, and an initial diagnostic partial biopsy of LM were included in the study. Histologic assessment was blinded to the presence of an invasive component.
All biopsy specimens were evaluated for the presence of certain histologic characteristics.
Comparisons between invasive samples and samples without an invasive component were performed. The differences in the distribution of variables between the groups were assessed using the χ2 and Fisher exact tests, and the degree of association of the relevant variables was quantified by logistic regression models. A classification and regression tree analysis was performed to rank the variables by importance.
In total, 96 patients had sufficient histologic material that could be evaluated. The patients were predominantly male (56 [58.3%]) and had a mean (SD) age at diagnosis of 72 (12) years. Of these patients, 63 (65.6%) had an LM diagnosis and 33 (34.4%) had an LMM diagnosis (an invasive component). The histologic variables associated with the presence of an invasive component were melanocytes forming rows (odds ratio [OR], 11.5; 95% CI, 1.4-94.1; P = .02), subepidermal clefts (OR, 2.8; 95% CI, 1.0-7.9; P = .049), nests (OR, 3.0; 95% CI, 1.1-8.6; P = .04), and a lesser degree of solar elastosis (OR, 0.4; 95% CI, 0.1-1.1; P = .07). A classification and regression tree analysis of the relevant histologic features was able to accurately identify lentigo maligna with an invasive component (LMM) in more than 60% of patients.
These findings may be useful in classifying early LM specimens at higher risk of invasion, which may eventually be relevant in identifying the most appropriate management for LM.
多达 20%的活检病例中，恶性雀斑样痣（LM）存在侵袭性成分，但迄今为止，尚未描述有助于检测这种侵袭性成分的组织学特征。一些组织学特征被假设有助于 LM 侵袭的进展。
在通过部分诊断性活检诊断为 LM 的患者中，确定与 LM 相关的组织学特征恶性雀斑样黑素瘤（LMM）。
设计、地点和参与者：这是西班牙巴伦西亚一家转诊肿瘤中心进行的一项回顾性病例对照研究。研究纳入了 2000 年 1 月 1 日至 2017 年 12 月 31 日期间接受手术治疗、整个肿瘤完整组织学检查和 LM 初始诊断性部分活检的患者（n=96），这些患者的诊断为原发性皮肤黑素瘤，包括 LM 或 LMM。组织学评估对侵袭性成分的存在是盲态的。
所有活检标本均评估了某些组织学特征的存在。
比较了有侵袭性成分的样本和没有侵袭性成分的样本。使用 χ2 和 Fisher 确切检验评估组间变量分布的差异，使用逻辑回归模型量化相关变量的关联程度。进行分类和回归树分析以按重要性对变量进行排序。
共纳入 96 例有足够组织学材料可供评估的患者。患者主要为男性（56[58.3%]），诊断时的平均（SD）年龄为 72（12）岁。这些患者中，63 例（65.6%）诊断为 LM，33 例（34.4%）诊断为 LMM（侵袭性成分）。与侵袭性成分存在相关的组织学变量包括形成行的黑素细胞（比值比[OR]，11.5；95%CI，1.4-94.1；P=0.02）、表皮下裂隙（OR，2.8；95%CI，1.0-7.9；P=0.049）、巢（OR，3.0；95%CI，1.1-8.6；P=0.04）和程度较低的太阳弹性纤维变性（OR，0.4；95%CI，0.1-1.1；P=0.07）。对相关组织学特征的分类和回归树分析能够准确识别出 60%以上患者的具有侵袭性成分的恶性雀斑样痣（LMM）。
这些发现可能有助于对具有较高侵袭风险的早期 LM 标本进行分类，这最终可能与确定 LM 的最佳管理方法有关。
