Department of Dermatology, CHUV Lausanne, University of Lausanne, Switzerland.
Division of Dermatology and Venereology, Geneva University Hospitals, Geneva, Switzerland.
Br J Dermatol. 2024 Jul 16;191(2):233-242. doi: 10.1093/bjd/ljae150.
Lymphomatoid papulosis (LyP) is a rare cutaneous T-cell lymphoproliferative disorder. Comprehensive data on LyP in the paediatric population are scarce.
To characterize the epidemiological, clinical, histopathological and prognostic features of paediatric LyP.
This was a retrospective multicentre international cohort study that included 87 children and adolescents with LyP diagnosed between 1998 and 2022. Patients aged ≤ 18 years at disease onset were included. LyP diagnosis was made in each centre, based on clinicopathological correlation.
Eighty-seven patients from 12 centres were included. Mean age at disease onset was 7.0 years (range 3 months-18 years) with a male to female ratio of 2 : 1. Mean time between the onset of the first cutaneous lesions and diagnosis was 1.3 years (range 0-14). Initial misdiagnosis concerned 26% of patients. LyP was most often misdiagnosed as pityriasis lichenoides et varioliformis acuta, insect bites or mollusca contagiosa. Erythematous papules or papulonodules were the most frequent clinical presentation. Pruritus was specifically mentioned in 21% of patients. The main histological subtype was type A in 55% of cases. When analysed, monoclonal T-cell receptor rearrangement was found in 77% of skin biopsies. The overall survival rate was 100%, with follow-up at 5 years available for 33 patients and at 15 years for 8 patients. Associated haematological malignancy (HM) occurred in 10% of cases (n = 7/73), including four patients with mycosis fungoides, one with primary cutaneous anaplastic large cell lymphoma (ALCL), one with systemic ALCL and one with acute myeloid leukaemia. If we compared incidence rates of cancer with the world population aged 0-19 years from 2001 to 2010, we estimated a significantly higher risk of associated malignancy in general, occurring before the age of 19 years (incidence rate ratio 87.49, 95% confidence interval 86.01-88.99).
We report epidemiological data from a large international cohort of children and adolescents with LyP. Overall, the disease prognosis is good, with excellent survival rates for all patients. Owing to an increased risk of associated HM, long-term follow-up should be recommended for patients with LyP.
蕈样肉芽肿（LyP）是一种罕见的皮肤 T 细胞淋巴瘤增生性疾病。儿科人群中 LyP 的综合数据非常有限。
描述儿科 LyP 的流行病学、临床、组织病理学和预后特征。
这是一项回顾性多中心国际队列研究，纳入了 1998 年至 2022 年间诊断的 87 例患有 LyP 的儿童和青少年。纳入的患者在发病时年龄均≤18 岁。在每个中心，根据临床病理相关性诊断 LyP。
纳入了来自 12 个中心的 87 名患者。发病时的平均年龄为 7.0 岁（3 个月至 18 岁），男女比例为 2:1。从首发皮肤病变到确诊的平均时间为 1.3 年（0 至 14 年）。26%的患者最初被误诊。LyP 最常被误诊为急性痘疮样苔藓样糠疹、虫咬或传染性软疣。最常见的临床表现为红斑性丘疹或丘疹结节。21%的患者有瘙痒症状。55%的病例为 A 型主要组织学亚型。分析时，77%的皮肤活检发现单克隆 T 细胞受体重排。总体生存率为 100%，有 33 名患者在 5 年时可获得随访，8 名患者在 15 年时可获得随访。10%的患者（7/73）发生了伴发血液恶性肿瘤（HM），包括 4 例蕈样真菌病、1 例原发性皮肤间变性大细胞淋巴瘤（ALCL）、1 例系统性 ALCL 和 1 例急性髓系白血病。如果我们将 2001 年至 2010 年 0-19 岁世界人口的癌症发病率进行比较，我们估计伴发恶性肿瘤的风险显著更高，通常发生在 19 岁之前（发病率比 87.49，95%置信区间 86.01-88.99）。
我们报告了来自一个大型国际儿童和青少年 LyP 队列的流行病学数据。总的来说，疾病的预后良好，所有患者的生存率均很高。由于伴发 HM 的风险增加，建议对 LyP 患者进行长期随访。
