Myrdal Caitlyn N, Sundararajan Srinath, Curiel-Lewandrowski Clara
University of Arizona College of Medicine Tucson, Tucson, Arizona, USA.
Hematology and Oncology, Texas Oncology, Houston, Texas, USA.
Case Rep Dermatol. 2020 Jun 18;12(2):119-123. doi: 10.1159/000508490. eCollection 2020 May-Aug.
Hypertrophic lichen planus (HLP) may not have the typical histological findings of lichen planus and often mimics squamous cell carcinoma (SCC). Distinguishing between the two can pose a diagnostic challenge. Here, we present a case of eruptive HLP mimicking SCC in the context of programmed cell death ligand 1 (PD-L1) immune checkpoint inhibition. A 73-year-old woman recently treated with durvalumab, an anti-PD-L1 antibody, presented to our clinic with diffuse hyperkeratotic papules and plaques previously thought to be eruptive SCC. The lesions did not respond to topical fluorouracil and continued to appear despite discontinuation of immunotherapy. Further histological analysis revealed intraepidermal epithelial proliferation with lichenoid inflammation. Subsequent treatment with topical corticosteroids significantly improved the size and number of lesions. The diagnosis of HLP was made based on histological features and response to topical steroids in the context of recent immunotherapy. This case reveals HLP as a potential adverse effect of PD-L1 inhibition and highlights the need for additional diagnostic assessment in patients presenting with eruptive hyperkeratotic lesions, especially on the lower extremities.
肥厚性扁平苔藓（HLP）可能不具有扁平苔藓典型的组织学表现，且常酷似鳞状细胞癌（SCC）。鉴别这两者可能构成诊断挑战。在此，我们报告一例在程序性细胞死亡配体1（PD-L1）免疫检查点抑制背景下酷似SCC的发疹性HLP病例。一名73岁女性近期接受了抗PD-L1抗体度伐鲁单抗治疗，前来我们诊所就诊，其身上有弥漫性角化过度丘疹和斑块，之前被认为是发疹性SCC。这些皮损对局部氟尿嘧啶治疗无反应，且尽管停止了免疫治疗仍持续出现。进一步的组织学分析显示表皮内上皮增生伴苔藓样炎症。随后局部使用糖皮质激素治疗使皮损大小和数量显著改善。基于组织学特征以及在近期免疫治疗背景下对局部糖皮质激素的反应，诊断为HLP。该病例揭示HLP是PD-L1抑制的一种潜在不良反应，并强调对于出现发疹性角化过度皮损的患者，尤其是下肢皮损患者，需要进行额外的诊断评估。
