Takada Daisuke, Tsukamoto Tatsuo, Fuse Miho, Kada Shinpei, Yanagita Motoko
Department of Nephrology, Kyoto University Graduate School of Medicine, 54 Shogoin Kawahara-cho, Sakyo, Kyoto, Japan.
Department of Nephrology & Dialysis, Kitano Hospital, The Tazuke Kofukai Medical Research Institute, Osaka, Japan.
BMC Nephrol. 2017 Oct 18;18(1):315. doi: 10.1186/s12882-017-0733-0.
Secondary hyperparathyroidism (SHPT) is a common complication in patients receiving chronic dialysis therapy. Although cinacalcet can control parathyroid function and bone turnover, preventing ectopic calcification remains challenging. Cinacalcet can also suppress PTH secretion due to parathyroid carcinoma in the same way as it does for parathyroid hyperplasia in the uremic condition. We present a case of parathyroid carcinoma partially controlled by cinacalcet, in which tumorous calcinosis was successfully resolved by total parathyroidectomy.
A female patient in her forties who had received dialysis for 12 years was referred to our hospital for painful ectopic calcifications on her right hip joint and both knees. Although she had been treated with alfacalcidol and cinacalcet for 2 years, this therapy had been discontinued 6 months earlier as a result of hypercalcemia. The patient exhibited normocalcemia (2.37 mmol/L) and hyperphosphatemia (2.42 mmol/L) with elevated intact parathyroid hormone (707,000 μg/L). Ultrasonography revealed an enlarged parathyroid gland on the left lower side of the thyroid gland. The otolaryngologist surgeons had to perform an en bloc excision to remove this parathyroid gland because of tight adhesions. Histological examination revealed that parathyroid cells had invaded the surrounding skeletal muscle through fibrous capsules, consistent with parathyroid carcinoma. Her joint pain disappeared 2 weeks after parathyroidectomy, and the tumorous calcinosis had largely resolved after 1 year.
Parathyroid carcinoma is a rare cause of hyperparathyroidism in end-stage kidney disease. Our case indicates that the use of cinacalcet hinders the diagnosis of parathyroid carcinoma in a chronic dialysis patient. When uncontrolled hypercalcemia and/or hyperphosphathemia develop during cinacalcet administration, parathyroidectomy should be considered to prevent a vicious exacerbation of ectopic calcification.
继发性甲状旁腺功能亢进（SHPT）是接受慢性透析治疗患者的常见并发症。尽管西那卡塞可以控制甲状旁腺功能和骨转换，但预防异位钙化仍然具有挑战性。西那卡塞还可以像在尿毒症状态下对甲状旁腺增生一样抑制甲状旁腺癌的甲状旁腺激素（PTH）分泌。我们报告一例西那卡塞部分控制的甲状旁腺癌病例，其中通过甲状旁腺全切术成功解决了肿瘤性钙化。
一名40多岁接受透析12年的女性患者因右髋关节和双膝疼痛性异位钙化被转诊至我院。尽管她接受阿法骨化醇和西那卡塞治疗2年，但由于高钙血症，该治疗在6个月前已停用。患者血钙正常（2.37 mmol/L），血磷升高（2.42 mmol/L），完整甲状旁腺激素升高（707,000 μg/L）。超声检查显示甲状腺左下方甲状旁腺肿大。由于粘连紧密，耳鼻喉科外科医生不得不进行整块切除以切除该甲状旁腺。组织学检查显示甲状旁腺细胞通过纤维包膜侵入周围骨骼肌，符合甲状旁腺癌。甲状旁腺切除术后2周她的关节疼痛消失，1年后肿瘤性钙化基本消退。
甲状旁腺癌是终末期肾病患者甲状旁腺功能亢进的罕见原因。我们的病例表明，西那卡塞的使用会妨碍对慢性透析患者甲状旁腺癌的诊断。当在西那卡塞给药期间出现无法控制的高钙血症和/或高磷血症时，应考虑甲状旁腺切除术以防止异位钙化的恶性加重。
