Department of Pathology and Laboratory Medicine, University of Vermont Medical Center, Burlington, Vermont.
Department of Pathology and Laboratory Medicine, Boston University Medical Center, Boston, Massachusetts.
Cancer Cytopathol. 2022 May;130(5):381-391. doi: 10.1002/cncy.22557. Epub 2022 Feb 1.
Determining human papillomavirus (HPV) status in oropharyngeal squamous cell carcinoma can have a significant impact on treatment and clinical outcomes. Because fine-needle aspiration (FNA) is typically an initial diagnostic modality in a patient workup for primary or suspected metastatic disease, immunostaining for p16 on FNA material is a promising option to determine HPV tumor status, possibly avoiding biopsies or excisions. In this study, the authors investigated the possibility of using alcohol-fixed smears as a reliable alternative for reporting p16 status.
Twenty HPV-associated tumors and 20 non-HPV-associated tumors were identified using the gold-standard histologic cutoff for positivity of ≥70% strong nuclear and cytoplasmic staining. Matched FNA specimens were identified for comparison staining, and a positive p16 result was rendered on a single aspirate smear using the same cutoff of ≥70%.
On alcohol-fixed cytology smears, 16 of 20 (80%) HPV-associated tumors showed positive p16 staining in ≥70% tumor cells. Four cases showed lower level (30%-60%) nuclear and cytoplasmic staining. Nineteen of 20 (95%) non-HPV-associated tumors showed no or minimal p16 staining (0%-10%), and 1 case had a p16-equivocal cytology result.
The authors performed immunocytochemical validation for p16 using alcohol-fixed smears and observed promising results, offering this technique as a potential alternative to formalin-fixed tissue in the appropriate clinical context. By using a positive staining cutoff of ≥70%, this technique offers 80% sensitivity and 95% specificity for detecting HPV-associated tumors. Although it was not performed in the current study, HPV-specific testing on available formalin-fixed, paraffin-embedded tissue should be considered in cases with equivocal or negative p16 staining.
确定口咽鳞状细胞癌中的人乳头瘤病毒（HPV）状态可能对治疗和临床结果有重大影响。由于细针抽吸（FNA）通常是患者原发性或疑似转移性疾病检查的初始诊断方式，因此在 FNA 材料上对 p16 进行免疫染色是确定 HPV 肿瘤状态的一种很有前途的选择，可能避免了活检或切除。在这项研究中，作者研究了使用酒精固定涂片作为报告 p16 状态的可靠替代方法的可能性。
使用阳性的≥70%强核和细胞质染色的组织学标准临界值，确定了 20 例 HPV 相关肿瘤和 20 例非 HPV 相关肿瘤。为了比较染色，确定了匹配的 FNA 标本，并且使用相同的临界值（≥70%）在单个抽吸涂片上获得了阳性的 p16 结果。
在酒精固定细胞学涂片上，20 例 HPV 相关肿瘤中有 16 例（80%）在≥70%的肿瘤细胞中显示出阳性的 p16 染色。4 例显示出较低水平（30%-60%）的核和细胞质染色。20 例非 HPV 相关肿瘤中有 19 例（95%）没有或仅有微小的 p16 染色（0%-10%），1 例具有 p16 不确定的细胞学结果。
作者使用酒精固定涂片进行了 p16 的免疫细胞化学验证，并观察到了有希望的结果，为在适当的临床情况下将该技术作为福尔马林固定组织的潜在替代方法提供了依据。通过使用≥70%的阳性染色临界值，该技术对头颈癌患者 HPV 相关肿瘤的检测具有 80%的敏感性和 95%的特异性。尽管在当前研究中未进行，但在 p16 染色不确定或阴性的情况下，应考虑对现有福尔马林固定、石蜡包埋组织进行 HPV 特异性检测。
