PDF(Pubmed)
Abstract：
UNASSIGNED: Thyroid hemiagenesis (THA) is the failure of embryologic development of a lobe of the thyroid gland and is a rare anomaly of uncertain incidence. The left lobe is more commonly absent than the right lobe. It is discovered incidentally during investigations.
METHODS: A 48 year old Egyptian female presented at the thyroid surgery clinic at our institution to follow up after a nodule left thyroid lobe accidently discovered on positron emission tomography (PET) scan undertaken to follow up on bone metastasis of breast cancer which was surgically removed about 14 years ago.
UNASSIGNED: The patient looked clinically well with no scar in the anterior of the neck, no palpable thyroid nodules, and no lymphadenopathy. Ultrasound imaging of the neck revealed absent right thyroid lobe tissue and a nodule was noted at the upper pole of the left thyroid. Laboratory tests unremarkable, with TSH (2.14 mIU/L), and FT4 (12.4 pmol/L) within normal range. Fine needle aspiration and cytology of the thyroid nodule revealed atypia of undetermined significance.
CONCLUSIONS: THA is rare and right THA is even rarer. It is usually asymptomatic, and diagnosis is mostly incidental while investigating symptoms due to pathology of the other thyroid lobe or any of the parathyroid glands. In much rarer circumstances, right THA might be discovered when investigating conditions not related to the thyroid or parathyroid glands years after the initial pathology as in the current case. Etiology is inconclusive but genetic factors could play a role. No treatment is required if no symptoms are present.
METHODS: A 48 year old Egyptian female presented at the thyroid surgery clinic at our institution to follow up after a nodule left thyroid lobe accidently discovered on positron emission tomography (PET) scan undertaken to follow up on bone metastasis of breast cancer which was surgically removed about 14 years ago.
UNASSIGNED: The patient looked clinically well with no scar in the anterior of the neck, no palpable thyroid nodules, and no lymphadenopathy. Ultrasound imaging of the neck revealed absent right thyroid lobe tissue and a nodule was noted at the upper pole of the left thyroid. Laboratory tests unremarkable, with TSH (2.14 mIU/L), and FT4 (12.4 pmol/L) within normal range. Fine needle aspiration and cytology of the thyroid nodule revealed atypia of undetermined significance.
CONCLUSIONS: THA is rare and right THA is even rarer. It is usually asymptomatic, and diagnosis is mostly incidental while investigating symptoms due to pathology of the other thyroid lobe or any of the parathyroid glands. In much rarer circumstances, right THA might be discovered when investigating conditions not related to the thyroid or parathyroid glands years after the initial pathology as in the current case. Etiology is inconclusive but genetic factors could play a role. No treatment is required if no symptoms are present.
摘要：
■甲状腺发育不全（THA）是甲状腺叶胚胎发育的失败，是一种罕见的不确定发生率的异常。左叶比右叶更常见。它是在调查期间偶然发现的。
方法：一名48岁的埃及女性出现在我们机构的甲状腺外科诊所，在正电子发射断层扫描（PET）扫描中意外发现甲状腺左叶结节，以随访大约14年前手术切除的乳腺癌骨转移。
■患者临床上看起来很好，颈部前部没有疤痕，未触及甲状腺结节,也没有淋巴结肿大.颈部超声成像显示右甲状腺叶组织缺失，并在左甲状腺上极发现结节。实验室测试不显著，TSH（2.14mIU/L），和FT4（12.4pmol/L）在正常范围内。甲状腺结节的细针穿刺和细胞学检查显示出意义不明的异型性。
结论：THA是罕见的，正确的THA甚至更罕见。它通常是无症状的，诊断主要是偶然的，同时调查由于其他甲状腺叶或任何甲状旁腺的病理学引起的症状。在更罕见的情况下，右THA可能是在调查与甲状腺或甲状旁腺无关的疾病时发现的，就像目前的情况一样。病因尚无定论，但遗传因素可能起作用。如果没有症状，则不需要治疗。
方法：一名48岁的埃及女性出现在我们机构的甲状腺外科诊所，在正电子发射断层扫描（PET）扫描中意外发现甲状腺左叶结节，以随访大约14年前手术切除的乳腺癌骨转移。
■患者临床上看起来很好，颈部前部没有疤痕，未触及甲状腺结节,也没有淋巴结肿大.颈部超声成像显示右甲状腺叶组织缺失，并在左甲状腺上极发现结节。实验室测试不显著，TSH（2.14mIU/L），和FT4（12.4pmol/L）在正常范围内。甲状腺结节的细针穿刺和细胞学检查显示出意义不明的异型性。
结论：THA是罕见的，正确的THA甚至更罕见。它通常是无症状的，诊断主要是偶然的，同时调查由于其他甲状腺叶或任何甲状旁腺的病理学引起的症状。在更罕见的情况下，右THA可能是在调查与甲状腺或甲状旁腺无关的疾病时发现的，就像目前的情况一样。病因尚无定论，但遗传因素可能起作用。如果没有症状，则不需要治疗。
