Department of Pathology, Koç University Hospital, Turkey.
Department of Pathology, Koç University Hospital, Turkey.
Ann Diagn Pathol. 2020 Oct;48:151592. doi: 10.1016/j.anndiagpath.2020.151592. Epub 2020 Aug 19.
Lymph node metastasis occurs in a subset of papillary microcarcinoma patients. We aimed to analyze the differences between metastatic and non-metastatic papillary microcarcinomas in order to identify a high-risk subgroup that is likely to require more aggressive treatment.
126 thyroidectomies with lymph node dissections (central ± lateral), diagnosed as papillary microcarcinoma, were reviewed.
Mean age of 126 patients (F/M = 3.3) was 42 years. Mean size of the largest tumor was 7 mm. Classical was the most frequently (89%) encountered subtype. Multiple histologic subtypes co-occurred in 19%. Lymphovascular invasion was present in 16% (n = 20). 55 (44%) and 71 (56%) cases were unifocal and multifocal, respectively. 90 cases (71%) were non-encapsulated with overall infiltrative tumor borders, whereas in 36 cases (29%), the tumor had a well-defined capsule. Among those, 23 (64%) had tumor capsule invasion. 47 (37%) cases had metastasis in lymph nodes. In univariate analysis, metastasis was associated with tumor size of >5 mm (p = 0.02), tumor burden of >5 mm (p = 0.03), lymphovascular invasion (p = 0.02) and non-encapsulation (p = 0.01). No associations were found regarding sex, age, histologic subtype, lymphocytic thyroiditis, tumor capsule invasion (in capsulated tumors), laterality and multifocality (p > 0.05). In multivariate analysis, lymphovascular invasion (p = 0.01, OR = 3.97, 95% CI 1.35-11.67), tumor size >0.5 cm (p = 0.031, OR = 2.92, 95% CI 1.10-7.71) and non-encapsulation (p = 0.033, OR = 2.85, 95% CI 1.08-7.51) were independent risk factors.
Size (largest tumor or sum of all foci) of >5 mm, non-encapsulation and lymphovascular invasion were independent predictors of LNM in PMs. Unifocal tumors metastasize the same as multifocal tumors, suggestive of the contribution of other factors. Patients with sporadically resected microcarcinomas should be carefully followed-up, especially those that harbor risk factors in histology.
淋巴结转移发生在一部分甲状腺微小乳头状癌患者中。我们旨在分析转移性和非转移性甲状腺微小乳头状癌之间的差异，以确定可能需要更积极治疗的高危亚组。
回顾性分析了 126 例接受甲状腺切除术和淋巴结清扫术（中央+侧方）的患者，这些患者均被诊断为甲状腺微小乳头状癌。
126 例患者的平均年龄（F/M=3.3）为 42 岁。最大肿瘤的平均大小为 7mm。经典型是最常见（89%）的亚型。19%的病例存在多种组织学亚型共存。16%（n=20）的病例存在血管淋巴管浸润。55 例（44%）和 71 例（56%）分别为单发和多发肿瘤。90 例（71%）为非包膜型，肿瘤边界呈整体浸润性，而在 36 例（29%）中，肿瘤具有明确的包膜。其中 23 例（64%）包膜受侵。47 例（37%）发生淋巴结转移。单因素分析显示，肿瘤大小>5mm（p=0.02）、肿瘤负荷>5mm（p=0.03）、血管淋巴管浸润（p=0.02）和非包膜型（p=0.01）与转移相关。而性别、年龄、组织学亚型、淋巴细胞性甲状腺炎、包膜侵犯（在包膜型肿瘤中）、侧别和多灶性（p>0.05）与转移无相关性。多因素分析显示，血管淋巴管浸润（p=0.01，OR=3.97，95%CI 1.35-11.67）、肿瘤大小>0.5cm（p=0.031，OR=2.92，95%CI 1.10-7.71）和非包膜型（p=0.033，OR=2.85，95%CI 1.08-7.51）是独立的危险因素。
最大肿瘤或所有病灶的大小（>5mm）、非包膜型和血管淋巴管浸润是 PM 发生 LNM 的独立预测因子。单发肿瘤和多发肿瘤的转移率相同，提示存在其他因素的影响。对于偶然切除的微癌患者应密切随访，特别是那些在组织学上存在危险因素的患者。
