Jie Weiping, Bai Jiaying, Yan Jing, Chi Yanting, Li Bin-Bin
Department of Oral Pathology, Peking University School and Hospital of Stomatology, National Clinical Research Center for Oral Diseases, National Engineering Laboratory for Digital and Material Technology of Stomatology, Beijing Key Laboratory of Digital Stomatology, Beijing, China.
Research Unit of Precision Pathologic Diagnosis in Tumours of the Oral and Maxillofacial Regions, Chinese Academy of Medical Sciences, Beijing, China.
Front Med (Lausanne). 2021 May 10;8:670305. doi: 10.3389/fmed.2021.670305. eCollection 2021.
Oral squamous cell carcinoma (OSCC) and oropharyngeal squamous cell carcinoma (OPSCC) are very common in head and neck malignancy. Intratumour heterogeneity (ITH) may hamper their responses to treatment. Hence, novel tumour sampling methods that reflect ITH are required. In this study, we investigated the clinical significance of multi-site tumour sampling (MSTS) to detect ITH in OSCC and OPSCC. One hundred eighty-two paired specimens were sampled by routine sampling (RS) or MSTS, respectively. Histologically, tumour grade, peri-tumoural vascular and lymphatic growth, perineural permeation, tumour necrosis, and muscle invasion were assessed. Immunohistochemically, the positive and average detection rates of P53(mutant), ki67 and CyclinD1 were detected. The exon 9 and exon 20 mutations of PIK3CA gene and the methylation status of the CDKN2A promoter were analysed. Microscopically, the detection rate of perineural permeation, the detection density of peri-tumoural vascular and lymphatic growth, necrosis and muscle invasion in MSTS were significantly more frequent than those in RP ( < 0.05, < 0.05, < 0.01, < 0.01). MSTS resulted in a higher detection rate of P53 (mutant), ki67, and CyclinD1 expression than did RS, but the difference was not significant. MSTS's detection rates in PIK3CA gene mutation and gene methylation sequencing in CDKN2A gene promoter region were both higher than RP ( < 0.05, < 0.01). To be emphasised, the hotspot mutation H1047Rwas detected in one MSTS specimen (case 24M5) but in no RS specimens. This study verified that MSTS's advantage in the reflection of morphological and molecular characteristics of OSCC and OPSCC. MSTS was more representative than RP. Therefore, MSTS can compensate the RP limitations in ITH detection especially in large tumours.
口腔鳞状细胞癌（OSCC）和口咽鳞状细胞癌（OPSCC）在头颈部恶性肿瘤中非常常见。肿瘤内异质性（ITH）可能会影响它们对治疗的反应。因此，需要能够反映ITH的新型肿瘤采样方法。在本研究中，我们调查了多部位肿瘤采样（MSTS）在检测OSCC和OPSCC中ITH的临床意义。分别通过常规采样（RS）或MSTS采集了182对标本。组织学上，评估肿瘤分级、肿瘤周围血管和淋巴管生长、神经周围浸润、肿瘤坏死和肌肉浸润情况。免疫组化检测P53（突变型）、ki67和细胞周期蛋白D1的阳性和平均检出率。分析PIK3CA基因的外显子9和外显子20突变以及CDKN2A启动子的甲基化状态。显微镜下观察，MSTS中神经周围浸润的检出率、肿瘤周围血管和淋巴管生长的检测密度、坏死和肌肉浸润均显著高于RS（<0.05，<0.05，<0.01，<0.01）。MSTS检测P53（突变型）、ki67和细胞周期蛋白D1表达的检出率高于RS，但差异不显著。MSTS对PIK3CA基因突变和CDKN2A基因启动子区域基因甲基化测序的检出率均高于RS（<0.05，<0.01）。需要强调的是, 在一个MSTS标本（病例24M5）中检测到热点突变H1047R，而RS标本中未检测到。本研究证实了MSTS在反映OSCC和OPSCC形态学和分子特征方面的优势。MSTS比RS更具代表性。因此，MSTS可以弥补RS在ITH检测方面的局限性，尤其是在大肿瘤中。
