乳腺癌甲状腺转移表现为与甲状腺微小乳头状癌及嗜酸细胞腺瘤碰撞瘤：一例病例报告。
完整摘要 · 中文译文
乳腺癌甲状腺转移不常见，其与原发性甲状腺肿瘤共存形成的碰撞瘤更为罕见，带来重要的诊断和治疗挑战。我们报告一例57岁女性激素受体阳性、HER2阴性乳腺癌患者，在初始治疗后13年出现疾病复发，表现为颈部肿块、持续干咳和吞咽困难。评估显示根据美国甲状腺协会（ATA）分类为中间可疑甲状腺结节，连续细针穿刺活检分别归类为Bethesda III和IV。右侧甲状腺切除术显示低分化转移性乳腺癌，经免疫组织化学证实，与1.8 mm甲状腺乳头状微小癌（PTMC）和7 mm嗜酸细胞腺瘤共存于同一甲状腺标本中，构成极为罕见的甲状腺碰撞瘤。分期检查随后显示全身转移性疾病，根据III期MONALEESA-3方案开始 ribociclib 联合氟维司群治疗。本病例凸显了激素受体阳性乳腺癌以甲状腺转移形式表现的极晚期复发可能性，说明了甲状腺碰撞瘤的诊断复杂性，并强调了在具有乳腺癌病史患者的甲状腺结节鉴别诊断中考虑转移性疾病的重要性。尽管当前证据不支持常规甲状腺筛查，本病例提出了以下问题： 对晚期复发高风险的选择性患者进行针对性甲状腺评估是否值得进一步前瞻性研究。
完整摘要 · 英文原文
Thyroid metastases from breast cancer are uncommon, and their coexistence with primary thyroid neoplasms as collision tumors is even rarer, posing important diagnostic and therapeutic challenges. We report the case of a 57-year-old woman with hormone receptor-positive, HER2-negative breast cancer who developed disease recurrence 13 years after initial treatment, presenting with a cervical mass, persistent dry cough, and dysphagia. Evaluation revealed an intermediate-suspicion thyroid nodule according to the American Thyroid Association (ATA) classification, with successive fine-needle aspiration biopsies categorized as Bethesda III and IV. Right hemithyroidectomy demonstrated poorly differentiated metastatic breast carcinoma, confirmed by immunohistochemistry, coexisting within the same thyroid specimen with a 1.8-mm papillary thyroid microcarcinoma (PTMC) and a 7-mm oncocytic adenoma, constituting an exceptionally rare thyroid collision tumor. Staging studies subsequently revealed systemic metastatic disease, and treatment with ribociclib plus fulvestrant was initiated according to the phase III MONALEESA-3 regimen. This case highlights the possibility of very late recurrence of hormone receptor-positive breast cancer presenting as thyroid metastasis, illustrates the diagnostic complexity of thyroid collision tumors, and emphasizes the importance of considering metastatic disease in the differential diagnosis of thyroid nodules in patients with a history of breast cancer. Although current evidence does not support routine thyroid screening, this case raises the question of whether targeted thyroid evaluation in selected patients at high risk of late recurrence warrants further prospective investigation.