Department of Surgical, Medical, Molecular Pathology and Critical Area, University of Pisa, Pisa, Italy.
Department of Clinical and Experimental Medicine, University of Pisa, Pisa, Italy.
Front Endocrinol (Lausanne). 2022 Mar 2;13:842424. doi: 10.3389/fendo.2022.842424. eCollection 2022.
Papillary thyroid carcinoma (PTC) with hobnail areas above 30% is classified as hobnail variant (HVPTC). Although it is widely accepted that HVPTC has a worse outcome than classical PTC, it is unclear whether PTC with hobnail features below 30% is as aggressive as HVPTC. We gathered the largest mono-institutional series of PTC with hobnail areas and HVPTC to evaluate differences in terms of pathological features of aggressiveness, molecular profile, and treatment outcome. A total of 99 PTC with hobnail features above 5% were retrospectively selected; 34 of them met the criteria for HVPTC (0.4% of all PTC diagnosed at our institution). All tumors showed high rates of extra-thyroidal extension (40.4%), lymph node metastasis (68.1% of patients with lymphadenectomy), and vascular emboli (49.5%), with no differences according to the 30% cutoff. On the other hand, distant metastases were present in HVPTC only (9.4%). Also, advanced age, advanced disease stage, and promoter mutation were associated with HVPTC. More than half of the patients with follow-up had structural or biochemical persistence after 1 year from surgery. Structural persistence was significantly more common in patients with HVPTC (37.5% vs. 8.7%), while no differences were observed considering structural and biochemical persistence together. The presence of hobnail features identifies locally aggressive tumors, and, consequently, it should be always acknowledged in the pathological report. However, tumors with more than 30% hobnail areas frequently present promoter mutations, advanced disease stage, and structural persistence after radioiodine ablation.
甲状腺乳头状癌（PTC）中超过 30%的钉突区被归类为钉突变异型（HVPTC）。虽然广泛认为 HVPTC 的预后比经典 PTC 差，但 PTC 中钉突特征低于 30%是否像 HVPTC 那样具有侵袭性尚不清楚。我们收集了最大的单一机构系列的 PTC 伴有钉突区和 HVPTC，以评估在侵袭性病理特征、分子谱和治疗结果方面的差异。回顾性选择了 99 例 PTC 钉突特征超过 5%的病例；其中 34 例符合 HVPTC 标准（我院诊断的所有 PTC 的 0.4%）。所有肿瘤均显示出较高的甲状腺外侵犯率（40.4%）、淋巴结转移率（行淋巴结清扫术的患者中有 68.1%）和血管内栓塞率（49.5%），但根据 30%的界限没有差异。另一方面，只有 HVPTC 有远处转移（9.4%）。此外，高龄、晚期疾病分期和启动子突变与 HVPTC 相关。超过一半的随访患者在手术后 1 年内存在结构或生化持续性。HVPTC 患者结构持续性明显更常见（37.5% vs. 8.7%），而同时考虑结构和生化持续性时则没有差异。钉突特征的存在可识别出局部侵袭性肿瘤，因此应始终在病理报告中予以承认。然而，钉突面积超过 30%的肿瘤常伴有启动子突变、晚期疾病分期和放射性碘消融后的结构持续性。
