Tantisattamo Ekamol, Ng Roland C K
Department of Medicine, John A. Burns School of Medicine, University of Hawai'i, Honolulu, HI 96813, USA.
Hawaii Med J. 2011 Jul;70(7):139-43.
Acquired isolated renal phosphate wasting associated with a tumor, known as oncogenic osteomalacia or tumor-induced osteomalacia, is a rare paraneoplastic syndrome caused by overproduction of fibroblast growth factor 23. Oncogenic osteomalacia is usually associated with benign mesenchymal tumors. Syndrome of inappropriate antidiuretic hormone secretion (SIADH), on the other hand, is a common paraneoplastic syndrome caused by small cell carcinoma (SCC). Concomitant oncogenic osteomalacia and SIADH associated with SCC is very rare with only 4 other cases reported in the literature. The authors report a case of small cell lung cancer (SCLC)-related renal wasting hypophosphatemia and concurrent SIADH, and review the literature reporting 9 other cases of SCC associated with oncogenic osteomalacia. Almost half of reported cases of renal phosphate wasting associated with SCC concomitantly presented with SIADH. These cases had initial serum phosphorus level lower and survival periods shorter than those without SIADH. This rare combination of a dual paraneoplastic syndrome and low serum phosphorus may be a poor prognostic sign. In addition, both renal phosphate wasting and SIADH usually occur in a short period of time before identification of SCC. Therefore, renal wasting hypophosphatemia with concomitant SIADH/hyponatremia should prompt a search for SCC rather than a benign mesenchymal tumor.
获得性孤立性肾性磷耗竭伴肿瘤，称为肿瘤性骨软化症或肿瘤诱导性骨软化症，是一种由成纤维细胞生长因子23过度产生引起的罕见副肿瘤综合征。肿瘤性骨软化症通常与良性间叶肿瘤相关。另一方面，抗利尿激素分泌不当综合征（SIADH）是一种由小细胞癌（SCC）引起的常见副肿瘤综合征。伴有SCC的肿瘤性骨软化症和SIADH非常罕见，文献中仅报道了另外4例。作者报告了1例与小细胞肺癌（SCLC）相关的肾性磷耗竭低磷血症并并发SIADH的病例，并回顾了文献中报道的另外9例与肿瘤性骨软化症相关的SCC病例。几乎一半与SCC相关的肾性磷耗竭报道病例同时伴有SIADH。这些病例的初始血清磷水平低于无SIADH的病例，生存期也更短。这种罕见的双重副肿瘤综合征与低血清磷的组合可能是预后不良的标志。此外，肾性磷耗竭和SIADH通常在SCC确诊前的短时间内出现。因此，伴有SIADH/低钠血症的肾性磷耗竭低磷血症应促使寻找SCC而非良性间叶肿瘤。
