涎腺腺样囊性癌的细胞学诊断及其与基底细胞腺瘤的鉴别

Cytologic diagnosis of adenoid cystic carcinoma of salivary glands and distinction from basal cell

目的分析涎腺腺样囊性癌（ADCC）的细胞学形态特点，探讨涎腺ADCC与基底细胞腺瘤（BCA）的细胞学鉴别。方法回顾性分析首都医科大学附属北京同仁医院2010年1月至2017年1月头颈部30例涎腺ADCC及12例涎腺BCA的细胞学涂片／印片。除2例ADCC为针吸涂片外，余病例均为组织印片。所有病例诊断均经组织学证实。结果ADCC的肿瘤性导管细胞呈三维簇状、实性片状或单个散在分布；半透明黏液小球常见（20／30，66．7％）；细胞核呈圆形、卵圆形，有不同程度（多为轻度）的异型性；核仁常见（21／30，70．0％），部分病例核仁明显；瘤细胞胞质稀少。ADCC细胞核的异型性具体表现在：（1）核染色深，核染色质粗或略粗、分布不均；（2）细胞核略大，且大小不一；（3）细胞核形状有不同程度（常为轻度）的不规则。核分裂象少见，30例ADCC均未见坏死。BCA细胞学形态特点部分与ADCC重叠，其与ADCC的不同之处主要在于：（1）单个散在分布的肿瘤性导管细胞少见：（2）半透明黏液小球少见（1／12）；（3）细胞核染色浅或略深，形状规则一致、大小均一、无异型性，较ADCC者小且更为细长，无核仁或见不明显小核仁；（4）瘤细胞胞质较ADCC丰富。结论涎腺ADCC与BCA细胞学表现既相互重叠又各有特点，绝大多数病例可通过细胞学诊断、鉴别。半透明黏液小球是细胞学诊断ADCC的重要线索，但不是该肿瘤的特异性改变。肿瘤性导管细胞核的异型性是诊断ADCC的必要条件，也是鉴别ADCC与BCA可靠的细胞学指标。

Objective To describe the cytologic features of adenoid cystic carcinoma （ADCC） of salivary glands, and to identify distinguishing cytologic features of ADCC and basal cell adenoma （BCA）. Methods A retrospective review of cytology smears of 30 eases of ADCC and 12 cases of BCA of salivary glands were performed. All cases were collected from Beijing Tongren Hospital, Capital Medical University from January 2010 to January 2017. Except for 2 aspirate smears of ADCC, all were touch imprint smears. All cases had further histological confirmation. Results Neoplastic ductal cells of ADCC were arranged in three-dimensional clusters, sheets and singles. Hyaline globules were found in most cases （20/30, 66. 7% ）. The nuclei were round to oval, showing varying degrees of nuclear atypia. These included （ 1 ） the nuclei were hyperehromatic, demonstrating coarse or slightly coarse, irregularly distributed chromatin; （2） the nuclei were slightly large and vary in size ; （ 3 ） appearance of the nuclei had a different degree of irregularity （often mild）. Nucleoli were common seen （21/30, 70. 0%）, and were prominent in some cases. Mitosis and necrosis were rare. Cytologically, BCA showed cell arrangements and nuclear features overlapped with those of ADCC. The cytologic difference between these two tumors included ： （ 1 ） the tumor cells presented rarely in singles; （2） hyaline globules were very uncommon （1/12） in BCA; （3） nuclei of BCA were hypochromatic or slightly hyperchromatic, homogeneous and uniform in appearance and size, overall without nuclear atypia and they were smaller and slender then those of ADCC and （4） individual ceils of BCA showed relatively abundant cytoplasm. Conclusions The cytologic features of ADCC and BCA both overlap and different from each other. Most cases can be diagnosed by cytologic examination. The presence of hyaline globules is an important diagnostic clue of ADCC, although not pathognomonic. Nuclear atypia of neoplastic ductal cells is an essential cytological feature in the diagnosis of ADCC, and is the most reliable point for differential diagnosis of ADCC and BCA.