THANC (Thyroid, Head and Neck Cancer) Foundation, 10 Union Square East, New York, NY, 10003, USA.
Department of Otolaryngology - Head and Neck Surgery, Stanford University Medical Center, Stanford, CA, USA.
World J Surg. 2020 Jun;44(6):1892-1897. doi: 10.1007/s00268-020-05399-0.
Current American Thyroid Association (ATA) guidelines state that patients with intermediate-risk papillary thyroid cancer (PTC) may benefit from remnant ablation. One criterion for intermediate-risk classification is >5 positive lymph nodes (LNs). We investigate whether performing step-sectioning of LNs increases the metastatic detection rate, thereby influencing ATA risk of recurrence (ROR) classification.
A retrospective review was conducted of cases in which ≥ 5 LNs were removed during thyroidectomy and ≤5 LNs were found positive for PTC. Step-sectioning was performed on the original tissue blocks. All slides were re-reviewed by a senior pathologist.
Twenty patients met study criteria. Step-sectioning significantly increased LN yield compared to standard sectioning. In total, we found 12 new positive lymph nodes; seven (58%) were in totally new lymph nodes, while five (42%) were in lymph nodes previously read as negative. All newly discovered metastases were classified as micrometastases (≤2 mm). Of the 15 patients originally classified as low-risk, the step-sectioning protocol impacted two patients (13%), increasing ROR stratification.
Intensive step-sectioning reveals additional micrometastases. More detailed analysis did not identify clinically significant nodal disease likely to impact the clinical course of patients in this study. Our study supports current standards of pathology specimen handling related to LN assessment and the impact on ATA ROR classification. Nonetheless, it is important for clinicians to understand their institution's sectioning protocol utilized to report positive and total LN counts, which could impact ATA risk stratification and denote the comprehensive nature of the LN dissection that was performed.
目前的美国甲状腺协会（ATA）指南指出，中危风险的甲状腺乳头状癌（PTC）患者可能受益于残余消融。中危分类的一个标准是阳性淋巴结（LNs）>5 个。我们研究了进行淋巴结分步切片是否会增加转移灶的检出率，从而影响 ATA 复发风险（ROR）分类。
对甲状腺切除术中切除≥5 个 LN 且仅发现≤5 个 LN 有 PTC 阳性的病例进行回顾性研究。对原始组织块进行分步切片。所有切片均由一位资深病理学家重新审查。
20 例患者符合研究标准。与标准切片相比，分步切片显著增加了 LN 的产量。总共发现了 12 个新的阳性淋巴结；7 个（58%）位于全新的淋巴结中，而 5 个（42%）位于之前被判定为阴性的淋巴结中。所有新发现的转移灶均被归类为微转移（≤2mm）。在 15 例最初被归类为低危的患者中，分步切片方案影响了 2 例患者（13%），增加了 ROR 分层。
密集的分步切片揭示了更多的微转移灶。更详细的分析并未发现可能影响本研究患者临床病程的具有临床意义的淋巴结疾病。我们的研究支持当前与 LN 评估相关的病理标本处理标准以及对 ATA ROR 分类的影响。然而，临床医生了解其机构用于报告阳性和总 LN 计数的切片方案非常重要，这可能会影响 ATA 风险分层，并表示进行了全面的淋巴结清扫。
