Hypercalcemia of malignancy--new insights into an old syndrome.
Hypercalcemia of malignancy--new insights into an old syndrome.
复制标题
恶性肿瘤高钙血症——对旧综合征的新见解。
作者：
P. Esbrit
高钙血症是一种常见的副肿瘤综合征。肿瘤通过与肿瘤产生增加骨溶解的各种细胞因子相关的局部机制诱发高钙血症。此外，许多肿瘤释放体液因子，主要是甲状旁腺激素（PTH）相关蛋白（PTHrP），它刺激骨吸收和/或肾小管钙重吸收，导致高钙血症。 PTHrP 与其他肿瘤相关细胞因子的相互作用可能解释与恶性肿瘤综合征高钙血症相关的一些非 PTH 样特征。通过识别各种 PTHrP 表位的检测，大多数高钙血症癌症患者的血浆或尿液中的免疫反应性 PTHrP 水平高于正常受试者。目前的数据支持这样的观点：PTHrP 也可能是促进肿瘤生长以及溶骨性转移发展的因素。有多种治疗方法可用于降低高钙血症癌症患者的血清钙。高钙血症的病理生理机制似乎是不同抗高钙血症治疗疗效的决定因素。
Hypercalcemia is a common paraneoplastic syndrome. Tumors induce hypercalcemia by a local mechanism associated with the tumor's production of various cytokines increasing bone osteolysis. In addition, many tumors release humoral factors, mainly parathyroid hormone (PTH)-related protein (PTHrP), which stimulates bone resorption and/or tubular calcium reabsorption leading to hypercalcemia. Interaction of PTHrP with other tumor-elaborated cytokines might explain some nonPTH-like features associated with the hypercalcemia of malignancy syndrome. Using assays recognizing various PTHrP epitopes, the majority of hypercalcemic cancer patients have higher immunoreactive PTHrP levels in either plasma or urine than normal subjects. Present data support the concept that PTHrP might also be a factor which promotes tumor growth and also the development of osteolytic metastasis. A variety of therapeutic approaches are available to lower serum calcium in hypercalcemic cancer patients. The pathophysiological mechanisms of hypercalcemia appear to be a determinant of the efficacy of different antihypercalcemic treatments.