Abstract：
OBJECTIVE: We aimed to describe the clinical characteristics of a large cohort of patients diagnosed with tumor-induced osteomalacia (TIO), with a focus on patients with non-localizing and malignant TIO.
METHODS: This is a retrospective cohort of TIO patients in an academic medical center, diagnosed between January 1998 to May 2023. We described their demographics, biochemistries, tumor features, localization, treatment and complications.
RESULTS: Of 68 patients diagnosed with TIO, 49 (72%) were localizing and 5 (7.4%) were malignant. Of 50 patients who attempted localizing procedures, 29 (58%) achieved cure. 20 (40%) had persistent disease due to wrong tumor targeted, or refractory or recurrent tumors, despite up to 6 procedural attempts. There was no difference in demographics, phosphorus or baseline fibroblast growth factor-23 (FGF23) levels between localizing versus non-localizing groups, and malignant versus non-malignant groups. Lower extremity was the commonest site of localization (37%), with 47% in bone and 53% in soft tissue. 60% of malignant cases were located in the trunk. Tumor size correlated with peak FGF23 (R=0.566, p<0.001) but was not associated with malignancy risk (p=0.479). A cut-off FGF23 of >20 times upper limit of normal in the presence of normal renal function (p=0.025), and recurrence after initial cure (p=0.013) were factors significantly associated with malignancy. The non-localizing group had lower survival than localizing group (p=0.0097).
CONCLUSIONS: TIO is a condition with significant morbidity. Very high FGF23 level and disease recurrence are associated with malignant disease. Reasons behind the observation of higher mortality in non-localizing TIO should be further explored.
METHODS: This is a retrospective cohort of TIO patients in an academic medical center, diagnosed between January 1998 to May 2023. We described their demographics, biochemistries, tumor features, localization, treatment and complications.
RESULTS: Of 68 patients diagnosed with TIO, 49 (72%) were localizing and 5 (7.4%) were malignant. Of 50 patients who attempted localizing procedures, 29 (58%) achieved cure. 20 (40%) had persistent disease due to wrong tumor targeted, or refractory or recurrent tumors, despite up to 6 procedural attempts. There was no difference in demographics, phosphorus or baseline fibroblast growth factor-23 (FGF23) levels between localizing versus non-localizing groups, and malignant versus non-malignant groups. Lower extremity was the commonest site of localization (37%), with 47% in bone and 53% in soft tissue. 60% of malignant cases were located in the trunk. Tumor size correlated with peak FGF23 (R=0.566, p<0.001) but was not associated with malignancy risk (p=0.479). A cut-off FGF23 of >20 times upper limit of normal in the presence of normal renal function (p=0.025), and recurrence after initial cure (p=0.013) were factors significantly associated with malignancy. The non-localizing group had lower survival than localizing group (p=0.0097).
CONCLUSIONS: TIO is a condition with significant morbidity. Very high FGF23 level and disease recurrence are associated with malignant disease. Reasons behind the observation of higher mortality in non-localizing TIO should be further explored.
摘要：
目的：我们旨在描述被诊断为肿瘤诱导的骨软化症（TIO）患者的临床特征，重点是非定位和恶性TIO患者。
方法：这是一个学术医疗中心的TIO患者的回顾性队列，在1998年1月至2023年5月之间诊断。我们描述了他们的人口统计,生物化学，肿瘤特征,本地化,治疗和并发症。
结果：在68例诊断为TIO的患者中，49例（72％）为定位，5例（7.4％）为恶性。在50名尝试定位手术的患者中，29(58%)取得治愈。20（40％）由于错误的肿瘤靶向而患有持续性疾病，或难治性或复发性肿瘤，尽管有6次程序性尝试。人口统计学没有差异，定位与非定位组之间的磷或基线成纤维细胞生长因子-23（FGF23）水平，以及恶性和非恶性组。下肢是最常见的定位部位（37%），骨占47％，软组织占53％。60%的恶性病例位于躯干。肿瘤大小与FGF23峰值相关（R=0.566，p<0.001），但与恶性肿瘤风险无关（p=0.479）。在肾功能正常的情况下，截止FGF23>20倍的正常上限（p=0.025），初始治愈后复发（p=0.013）是与恶性肿瘤显著相关的因素。非定位组的生存率低于定位组（p=0.0097）。
结论：TIO是一种具有显著发病率的疾病。很高的FGF23水平和疾病复发与恶性疾病有关。应进一步探讨在非本地化TIO中观察到较高死亡率的原因。
方法：这是一个学术医疗中心的TIO患者的回顾性队列，在1998年1月至2023年5月之间诊断。我们描述了他们的人口统计,生物化学，肿瘤特征,本地化,治疗和并发症。
结果：在68例诊断为TIO的患者中，49例（72％）为定位，5例（7.4％）为恶性。在50名尝试定位手术的患者中，29(58%)取得治愈。20（40％）由于错误的肿瘤靶向而患有持续性疾病，或难治性或复发性肿瘤，尽管有6次程序性尝试。人口统计学没有差异，定位与非定位组之间的磷或基线成纤维细胞生长因子-23（FGF23）水平，以及恶性和非恶性组。下肢是最常见的定位部位（37%），骨占47％，软组织占53％。60%的恶性病例位于躯干。肿瘤大小与FGF23峰值相关（R=0.566，p<0.001），但与恶性肿瘤风险无关（p=0.479）。在肾功能正常的情况下，截止FGF23>20倍的正常上限（p=0.025），初始治愈后复发（p=0.013）是与恶性肿瘤显著相关的因素。非定位组的生存率低于定位组（p=0.0097）。
结论：TIO是一种具有显著发病率的疾病。很高的FGF23水平和疾病复发与恶性疾病有关。应进一步探讨在非本地化TIO中观察到较高死亡率的原因。
