Department of Dermatology and University of California, San Francisco.
Department of Pathology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.
Am J Clin Pathol. 2019 May 3;151(6):551-560. doi: 10.1093/ajcp/aqz001.
We observed keratoses with "clonal" nests present as numerous tiny collections, in which cells in "pagetoid" array are found, a configuration we termed microclonal seborrheic keratosis (MSK). To better distinguish MSK from pagetoid Bowen disease (PBD), we investigated use of immunohistochemical staining.
Biopsy specimens of 26 MSKs, 17 PBDs, and 11 borderline cases were reviewed for histopathology and stained with p53, Ki-67, and p16.
High expression of Ki-67 and p16 was observed in 12 (80%) of 15 PBDs and in one (4%) of 23 MSKs. Low expression of p16 and high expression of Ki-67 were observed in 16 (70%) of 23 MSKs and in two (13%) of 15 PBDs. Expression of p16 was elevated in 12 (80%) of 15 PBDs and in three (13%) of 23 MSKs (P < .0001).
We describe a "microclonal" variant of seborrheic keratosis with morphology sometimes challenging to distinguish from PBD. High expression of p16 and Ki-67 or p16 alone favors the diagnosis of PBD over MSK.
我们观察到角化病具有“克隆”巢，呈许多微小集合存在，其中发现细胞呈“派杰样”排列，我们将这种形态称为微克隆脂溢性角化病（MSK）。为了更好地区分 MSK 与派杰样 Bowen 病（PBD），我们研究了免疫组织化学染色的应用。
回顾了 26 例 MSK、17 例 PBD 和 11 例交界性病例的活检标本，进行组织病理学检查，并进行 p53、Ki-67 和 p16 染色。
15 例 PBD 中有 12 例（80%）Ki-67 和 p16 高表达，23 例 MSK 中有 1 例（4%）Ki-67 和 p16 高表达。23 例 MSK 中有 16 例（70%）p16 低表达和 Ki-67 高表达，15 例 PBD 中有 2 例（13%）p16 低表达和 Ki-67 高表达。15 例 PBD 中有 12 例（80%）p16 表达升高，23 例 MSK 中有 3 例（13%）p16 表达升高（P<0.0001）。
我们描述了脂溢性角化病的一种“微克隆”变体，其形态有时难以与 PBD 区分。p16 和 Ki-67 高表达或仅 p16 高表达支持 PBD 而非 MSK 的诊断。
