Martin Arthur, Gouveia Bruna Melhoranse, Rawson Robert, Guitera Pascale
The Melanoma Institute of Australia, New South Wales, Australia.
Medical School of The University of Sydney, Sydney, New South Wales, Australia.
J Dermatol. 2022 Jul;49(7):703-709. doi: 10.1111/1346-8138.16390. Epub 2022 May 5.
Lentigo maligna (LM) can be difficult to diagnose and recurrence is not uncommon. In vivo reflectance confocal microscopy (RCM) improves diagnostic accuracy of LM. LM can be difficult to discern from coexistent metal-induced cutaneous hyperpigmentation (MICH). We are the first to describe three cases of LM associated with gold, silver, and metal oxide (from tattoos) and the RCM findings, respectively. The images obtained via RCM were analyzed by two RCM experts, and histopathology reviewed by a dermatopathologist. MICH under RCM appeared as intensely hyperreflective dots (when found freely) or clusters of variable sizes (when engulfed by macrophages) limited to the dermis. Dermal dendritic cells and melanophages were also found in association but distinct from the confluence of dendritic cells at the dermoepidermal junction observed in LM. We showed longitudinal changes within the dermis in MICH, not previously reported, where these hyperreflective dots congregate into clusters. RCM was able to distinguish the features of LM from MICH, delineate treatment margins, and monitor for recurrence.
恶性雀斑样痣（LM）可能难以诊断，且复发并不罕见。体内反射式共聚焦显微镜（RCM）可提高LM的诊断准确性。LM可能难以与并存的金属诱导性皮肤色素沉着（MICH）相鉴别。我们首次分别描述了3例与金、银及金属氧化物（来自纹身）相关的LM及其RCM表现。通过RCM获得的图像由两名RCM专家进行分析，组织病理学由一名皮肤病理学家进行复查。在RCM下，MICH表现为局限于真皮层的强反射性小点（当自由存在时）或大小不一的簇状（当被巨噬细胞吞噬时）。真皮树突状细胞和黑素巨噬细胞也有发现，但与LM中在真皮表皮交界处观察到的树突状细胞融合不同。我们展示了MICH真皮层内此前未报道的纵向变化，即这些强反射性小点聚集形成簇状。RCM能够区分LM与MICH的特征，划定治疗边界并监测复发情况。
