口咽部人乳头状瘤病毒阳性鳞状细胞癌临床病理学观察

Clinicopathological characteristics of HPV^+ oropharyngeal squamous cell carcinoma

目的探讨口咽部人乳头状瘤病毒阳性鳞状细胞癌(OPSCC-HPV)的临床病理学特征和人乳头状瘤病毒(HPV)原位杂交不同检测方法在病理诊断中的作用。方法收集北京同仁医院2016年1月至2018年8月临床及病理资料较齐全,符合2017年WHO头颈部肿瘤分类诊断标准的OPSCC-HPV 15例,分析其临床病理特点;免疫组织化学染色采用EnVision法,对15例肿瘤组织进行了p16、p53及Ki-67的染色;原位杂交方法检测了10例肿瘤组织HPV 6/11型及16/18型的DNA;RNAscope法检测了11例肿瘤组织的HPV16型及18型E6及E7的mRNA。结果15例OPSCC-HPV病例发病年龄为30~69岁,中位年龄47岁。男性8例,女性7例。临床上颈部肿物6例,扁桃体肿大7例,舌根肿物1例,吞咽疼痛1例,颈部肿物影像学检查多表现为囊性。镜下肿瘤组织主要表现为非角化性鳞状细胞癌,颈部肿物表现为淋巴结内转移,伴结内囊性变,淋巴结被膜呈纤维性增厚;发生于扁桃体者癌细胞呈巢状及分叶状浸润至隐窝被覆上皮下,可为多中心性,癌巢内常伴中心性粉刺样坏死,高核质比及高核分裂活性;背景为淋巴组织。15例患者组织免疫组织化学p16染色全部为强阳性,Ki-67阳性指数较高(达60%~90%),p53弱阳性/阴性。HPV16/18 DNA检测结果1例弱阳性(1/10),9例阴性(9/10),HPV6/11 DNA均为阴性(10/10)。HPV16 mRNA检测11例全部为强阳性(11/11),其中1例HPV18 mRNA阳性(1/11),10例阴性(10/11)。结论OPSCC-HPV具有独特的临床病理学特点,证实OPSCC-HPV主要与HPV16相关,偶见混合HPV18感染;原位杂交RNAscope法检测高危型HPV16 mRNA在最后诊断及病原学鉴定上具有重要意义。

Objective To observe the clinicopathologic features of oropharyngeal squamous cell carcinoma associated with human papilloma virus (OPSCC-HPV) and discuss the role and value of different in situ hybridization (ISH) detection methods for HPV in pathologic diagnosis.Methods Fifteen cases of OPSCC-HPV were collected from Department of Pathology, Beijing Tongren Hospital, Capital Medical University from January 2016 to August 2018. These cases were diagnosed in accordance with the WHO classification of head and neck tumors. The histopathologic features and the clinicopathologic data were retrospectively analyzed. Immunohistochemistry (two-step EnVision method) was done to evaluate the expression of p16, Ki-67 and p53. ISH was used to detect HPV DNA (6/11 and 16/18). RNAscope technology was used to evaluate the presence of HPV mRNAs (16 and 18).Results The mean age for the 15 patients (8 males, 7 females) was 47 years (range from 30 to 69 years). OPSCC-HPV typically presentedat an advanced clinical stage, six patients had cervical lymphadenopathy (large and cystic), seven had tonsillar swelling, one had tumor at base of tongue, and one had odynophagia. Microscopically the tumors exhibited distinctive non-keratinizing squamous cell carcinoma morphology. Cervical nodal metastases were large and cystic, with thickening of lymph node capsules. OPSCC-HPV raised from crypt epithelium and extended beneath the tonsillar surface epithelial lining as nests and lobules, often with central necrosis. Tumor cells displayed a high N: C ratio, and high mitotic and apoptotic rates. Tumor nests are often embedded within lymphoid stroma, and may be infiltrated by lymphoid cells.Fifteen cases (15/15) were strongly positive for p16;Ki-67 index were 60%-90%;they were focally positive or negative for p53. Ten cases (10/10) were negative for HPV 6/11 DNA, and one case(1/10) was focally positive for HPV16/18 DNA. Eleven cases (11/11) were strongly positive for HPV16 mRNA, one case was focally positive for HPV18 mRNA.Conclusions OPSCC-HPV is a pathologically and clinically distinct form of head and neck squamous cell carcinoma. OPSCC-HPV is associated with high-risk HPV (type 16) in all cases. Detection of high-risk HPV16 mRNA by RNAscope is of great significance in the final diagnosis and pathogen identification.