BACKGROUND Primary hyperparathyroidism is a rare condition of disease which can seldomly present as giant retrotrhyroideal cysts, complicating the localization of the adenoma to resect. CASE PRESENTATION A 56-year old female presented with hypercalcaemia of 3.38 mmol/L (2.2-2.65 mmol/L) and a history of breast cancer. A fast growing cystic parathyroidal adenoma was diagnosed by a multimodal approach including comprehensive diagnostic imaging (ultrasonography, scintigraphies, dynamic MRI) and cytopathological investigations after ultrasonography-guided puncture. The patient was cured by surgical extraction of the whole adenoma. In retrospect, the rapid growth was most likely induced by cinacalcet (initially 30 mg/d, later 60 mg/d) therapy which the patient received for few months only. Primary hyperparathyroidism was ascertained because surgical removal of the solitary adenoma cured the patient. Furthermore, there was no relevant renal insufficiency or history of prolonged calcium-level deregulation. CONCLUSIONS This phenomenon of cystic degeneration of parathyroidal adenoma under therapy with cinacalcet has previously been described in secondary hyperparathyroidism, but not in primary hyperparathyroidism and should be considered in diagnostic approach.

中文翻译：

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西那卡塞特诱导的囊性甲状旁腺腺瘤快速生长的病例报告。

背景技术原发性甲状旁腺功能亢进症是一种罕见的疾病，很少会以巨大的脉络膜后囊肿的形式出现，使腺瘤的定位变得复杂。病例介绍一名56岁的女性高钙血症为3.38 mmol / L（2.2-2.65 mmol / L），有乳腺癌史。通过多模式方法诊断出快速增长的囊性甲状旁腺腺瘤，包括综合诊断成像（超声检查，闪烁显像，动态MRI）以及超声引导下穿刺后的细胞病理学检查。通过手术切除整个腺瘤治愈了病人。回想起来，西那卡塞（最初为30 mg / d，之后为60 mg / d）治疗很可能会导致患者迅速生长，而该治疗仅接受了几个月的治疗。确定原发性甲状旁腺功能亢进症是因为手术切除孤立性腺瘤治愈了患者。此外，没有相关的肾功能不全或长期钙水平失调的病史。结论先前曾在继发性甲状旁腺功能亢进症中描述过这种用cinacalcet治疗的甲状旁腺腺瘤的囊性变性现象，但在原发性甲状旁腺功能亢进中没有这种现象，应在诊断方法中加以考虑。