Kikuchi Kentaro, Nagao Toshitaka, Ide Fumio, Takizawa Shota, Sakashita Hideaki, Tsujino Ichiro, Li Tie-Jun, Kusama Kaoru
Division of Pathology, Department of Diagnostic and Therapeutic Sciences, Meikai University School of Dentistry, 1-1 Keyakidai, Sakado, Saitama, 350-0283, Japan.
Department of Oral Pathology, Peking University School of Stomatology, 22 South Zhongguancun Avenue Haidian District, Beijing, 100081, People's Republic of China.
Head Neck Pathol. 2019 Jun;13(2):131-139. doi: 10.1007/s12105-018-0916-4. Epub 2018 Mar 29.
Polymorphous adenocarcinoma (PAC) is the second most common intraoral malignant neoplasm of the minor salivary glands. However, it is very rare for PAC to show high-grade transformation (HGT) and to our knowledge, the English literature only seven reported cases. HGT tends to be observed when PAC recurs, and it is extremely rare to be seen at initial presentation. Here we report a 43-year-old Japanese male patient with PAC of the right palate showing HGT at initial presentation. Histopathologically, the tumor was characterized by a prominent solid and papillary-cystic growth pattern, with nuclear atypia and necrosis in area of HGT. The immunohistochemical staining pattern was consistent with PAC, as the tumor cells showed diffuse positivity for cytokeratin, vimentin and S-100, and focal positivity for bcl-2, ɑ-SMA and EMA. The tumor cells in HGT areas were markedly positive for AR and Ki-67 (about 40%/HPF), and also focally positive for cyclin D1 and p53, whereas HER2/neu, ER, PgR, p63, D2-40, GCDFP-15, and mitochondria were negative. Here we present a very rare case of palatal PAC with HGT at initial presentation.
多形性腺癌（PAC）是小唾液腺第二常见的口腔内恶性肿瘤。然而，PAC发生高级别转化（HGT）的情况非常罕见，据我们所知，英文文献中仅报道了7例。HGT往往在PAC复发时出现，在初次就诊时极为罕见。在此，我们报告一名43岁的日本男性患者，其右腭部的PAC在初次就诊时即表现为HGT。组织病理学上，肿瘤的特征为显著的实性和乳头状囊性生长模式，在HGT区域有核异型性和坏死。免疫组化染色模式与PAC一致，肿瘤细胞对细胞角蛋白、波形蛋白和S-100呈弥漫阳性，对bcl-2、α-SMA和EMA呈局灶阳性。HGT区域的肿瘤细胞对AR和Ki-67明显阳性（约40%/高倍视野），对细胞周期蛋白D1和p53也呈局灶阳性，而HER2/neu、ER、PgR、p63、D2-40、GCDFP-15和线粒体均为阴性。在此，我们展示了一例非常罕见的初次就诊时即表现为HGT的腭部PAC病例。
