摘要To the editor:Parathyroid carcinoma is an uncommon cause of parathyroid hormone (PTH)-dependent hypercalcemia and its timely diagnosis and treatment remains a clinical challenge.1 Here,we report a case in which extremely rare distinct metastatic foci of parathyroid carcinoma within the fourth lumbar vertebra was found.A 53-year-old man was admitted to a local hospital with persistent symptoms of generalized weakness,nausea,and vomiting on February 8,2012.Primary hyperparathyroidism and right sided parathyroid adenoma was diagnosed and right parathyroidectomy was performed.But,the patient's hypercalcemia remained and he underwent en bloc resection.Unfortunately,his calcium level still fluctuated between 3.08-4.60 (normal,2.08-2.60) mmol/L and the PTH level was 283.9 (normal,15-65) ng/L.The patient was transferred to our hospital on May 2 and he was found severely hypercalcemic upon admission (serum calcium:4.43 mmol/L;PTH:3 235 ng/L).10.3760/cma.j.issn.0366-6999.20132122.