甲状腺内胸腺癌临床病理分析

Clinicopathological Features of Intrathyroid Thymic Carcinoma

目的探讨甲状腺内胸腺癌的临床病理学特征,免疫组织化学特点、诊治及预后。方法收集7例甲状腺内胸腺癌患者的临床资料,行组织学观察及免疫组织化学染色,采用EB病毒(EBV)原位杂交检测EBV感染情况。结果7例患者中,男5例,女2例,中位年龄54岁(40~71岁)。肿瘤均位于甲状腺内,平均最大径(4.0±1.2)cm(2.2~6.0 cm)。所有患者均行甲状腺腺叶切除及局部淋巴结清扫术,术后均辅助放疗,其中5例接受化疗。6例患者获得随访,时间10~163个月,随访病例均存活,其中2例多次局部复发,1例同侧颈部淋巴结转移,其余病例未发现复发或转移。所有病例均阳性表达CK-pan、P63、CD5、CD117,不表达TTF-1、TG、CT和PAX8,其中1例弥漫表达SYN和CgA,Ki-67增殖指数在10%~90%。7例EBV原位杂交均为阴性。结论甲状腺内胸腺癌是一种相对少见的惰性肿瘤,免疫组织化学CD5、CD117及单克隆PAX8组合有助于其诊断及鉴别诊断。EBV可能不参与甲状腺内胸腺癌的发生。手术腺叶全切加中央区淋巴结清扫是治疗甲状腺内胸腺癌的重要治疗手段,对有区域淋巴结转移和明显周围组织侵犯的患者,术后辅助放疗和/或联合化疗可有效延缓疾病进展。

Objective To investigate the clinicopathological features,immunohistochemical characteristics,diagnosis,treatment and prognosis of intrathyroid thymic carcinoma.Methods Clinical data of 7 patients with intrathyroid thymic carcinoma were retrospectively reviewed.Histological examination and immunohistochemical staining were performed on the surgically resected tumors.The infection of Epstein-Barr virus(EBV)was detected by EBER in situ hybridization.Results The 7 patients included 5 males and 2 females.The age ranged from 40 to 71 years,with a median of 54 years.The tumors were located in the thyroid gland,with the maximum diameter ranging from 2.2 cm to 6.0 cm and the average maximum diameter of(4.0±1.2)cm.All the patients underwent thyroid gland resection and local lymph node dissection.After operation,all the cases were treated with radiotherapy and five of them additionally received chemotherapy.Six patients were followed up for 10-163 months,all of whom were still alive,including 2 patients with recurrence in situ,1 patient with homolateral cervical lymph node metastasis and the rest with no recurrence or metastasis.CK-pan,P63,CD5 and CD117 were expressed in all the cases,while TTF-1,TG,CT and PAX8 were negative.One case of them expressed SYN and CgA.Ki-67 proliferation index ranged from 10%to 90%.EBER in situ hybridization showed negative results in all 7 cases.Conclusions Intrathyroid thymic carcinoma is a relatively low-grade malignant tumor.The combination of immunohistochemical CD5,CD117 and monoclonal PAX8 is helpful in the diagnosis and differential diagnosis of intrathyroid thymic carcinoma.EBV may not be involved in the development of intrathyroid thymic carcinoma.Thyroid gland resection plus central lymph node dissection is an important treatment measure for intrathyroid thymic carcinoma.For patients with regional lymph node metastasis and obvious peripheral tissue invasion,postoperative radiotherapy with/without chemotherapy can effectively delay the disease progression.