Department of Otolaryngology-Head and Neck Surgery, Hokuto Hospital, Inadacho Kisen 7-5, Obihiro, Hokkaido, 080-0833, Japan.
Department of Otolaryngology-Head and Neck Surgery, Asahikawa Medical University, Midorigaoka-Higashi 2-1-1-1, Asahikawa, Hokkaido, 078-8510, Japan.
Head Neck Pathol. 2022 Mar;16(1):282-287. doi: 10.1007/s12105-021-01339-z. Epub 2021 Jun 2.
A 15-year-old old Japanese male with a 2-month history of swelling of his left subauricular area was admitted to our department. A thumb-sized, hard mass with mild tenderness was palpated on the left parotid gland. Ultrasonography revealed a well-circumscribed, hypoechoic mass exhibiting heterogeneity in the left parotid gland measuring 1.7 × 1.5 × 1.3 cm. Computed tomography scan revealed a well-circumscribed, solid mass exhibiting slight peripheral enhancement in the left parotid gland. Magnetic resonance imaging revealed a hypointense mass in the left parotid gland on both T1- and T2-weighted images. Clinicoradiologic findings suggested a benign or low-grade malignant parotid tumor. The patient underwent left superficial parotidectomy with adequate safety margins. The facial nerve was identified and preserved. Neither facial paralysis nor tumor recurrence was observed as of 1 year postoperatively. Histologically, the nodule consisted of a vaguely nodular arrangement of variably sized ducts and acini in a hyalinized fibrous background with focal myxoid changes. The ductal/acinar component exhibited a bilayered arrangement of cuboidal luminal and flattened abluminal cells exhibiting a variety of epithelial proliferative patterns, including micropapillary and cribriform. Areas of oncocyte-like changes with intracellular coarse eosinophilic granules, apocrine-like feature, foamy/vacuolated changes, and clear cells were noted in the proliferating epithelium. Immunohistologically, the luminal cells were positive for gross cystic disease fluid protein-15. The Ki-67 labeling index was 2-3%. The histologic features and immunohistologic profile were consistent with sclerosing polycystic adenosis. Targeted next-generation sequencing of 160 cancer-related genes using the surgical specimen revealed no mutations, including known significant mutations in PTEN, PIK3CA, or PIK3R1.
一位 15 岁的日本男性，2 个月前左耳垂下出现肿胀，因左侧腮腺区有一拇指大小的硬性肿块，触之有轻度压痛，来我院就诊。超声检查显示左侧腮腺内有一边界清楚的低回声肿块，大小约为 1.7×1.5×1.3cm，呈异质性。CT 扫描显示左侧腮腺内有一边界清楚的实性肿块，轻度周边增强。磁共振成像显示左侧腮腺内有一低信号肿块，T1 和 T2 加权图像均为低信号。临床和影像学检查结果提示为良性或低度恶性腮腺肿瘤。患者接受了左侧腮腺浅叶切除术，切除范围足够安全。面神经被识别并保留。术后 1 年，未出现面瘫或肿瘤复发。组织学上，该结节由大小不一的导管和腺泡呈模糊结节状排列在玻璃样纤维化背景中，伴有局灶黏液样变。导管/腺泡成分呈双层立方腔和扁平腔细胞排列，具有多种上皮增生模式，包括微乳头状和筛状。在增生的上皮中可见类似于癌性体的变化，胞质内有粗嗜酸性颗粒、大汗腺样特征、泡沫/空泡化改变和透明细胞。免疫组织化学显示，腔细胞对大体囊性疾病液体蛋白-15 呈阳性。Ki-67 标记指数为 2-3%。组织学特征和免疫组织化学特征与硬化性多囊性腺病一致。使用手术标本对 160 个与癌症相关的基因进行靶向下一代测序，未发现突变，包括 PTEN、PIK3CA 或 PIK3R1 中已知的显著突变。
