Research Institute and Hospital, National Cancer Center, Gyeonggi, Korea.
Head Neck. 2010 Jan;32(1):68-75. doi: 10.1002/hed.21145.
Serum calcitonin is the most useful tumor marker for the diagnosis and follow-up of medullary thyroid carcinoma (MTC). Spurious hypercalcitoninemia caused by heterophilic antibody interference (HAI) is rarely found in patients without MTC.
We studied 2 patients with hypercalcitoninemia and thyroid nodules, but no evidence of MTC on fine-needle aspiration cytology. We performed calcium stimulation tests, measured serum calcitonin with another calcitonin kit, performed dilution tests, and remeasured serum calcitonin after applying heterophilic blocking tubes.
In a 31-year-old woman with no response to the calcium stimulation test, serum calcitonin was <5 pg/mL using another kit. After we applied heterophilic blocking tubes, the serum calcitonin level decreased to normal range. We concluded that patient had spurious hypercalcitoninemia. In a 63-year-old woman, all tests revealed that the patient had true hypercalcitoninemia. The patient underwent total thyroidectomy that revealed MTC.
We suggest that patients suspected for spurious hypercalcitoninemia should undergo further investigation due to HAI.
降钙素是诊断和随访甲状腺髓样癌（MTC）最有用的肿瘤标志物。在没有 MTC 的患者中，很少发现由异嗜性抗体干扰（HAI）引起的假性降钙素血症。
我们研究了 2 名降钙素升高且伴有甲状腺结节的患者，但细针穿刺细胞学检查未发现 MTC。我们进行了钙刺激试验，使用另一种降钙素试剂盒测量了血清降钙素，进行了稀释试验，并在应用异嗜性封闭管后重新测量了血清降钙素。
在一名 31 岁的女性患者中，钙刺激试验无反应，使用另一种试剂盒时血清降钙素<5 pg/mL。应用异嗜性封闭管后，血清降钙素水平降至正常范围。我们得出结论，患者存在假性降钙素血症。在一名 63 岁的女性患者中，所有检查均表明患者存在真性降钙素血症。患者接受了全甲状腺切除术，结果显示为甲状腺髓样癌。
我们建议怀疑假性降钙素血症的患者应因 HAI 而进行进一步检查。
