DIAGNOSTIC AND TREATMENT MONITORING POTENTIAL OF SERUM VASCULAR ENDOTHELIAL GROWTH FACTOR-D IN LYMPHANGIOLEIOMYOMATOSIS

Abstract

Lymphangioleiomyomatosis (LAM) is a rare multisystem disease occurring almost exclusively in premenopausal women and characterized by cystic lung destruction, abdominal tumors (renal angiomyolipomas (AML)), and involvement of the axial lymphatics (adenopathy, lymphangioleiomyomas). Serum vascular endothelial growth factor-D (VEGF-D), a lymphangiogenic factor, has been recently considered as a novel marker for LAM. Herein we report the diagnostic and differential diagnostic value of serum VEGF-D in LAM patients and evaluate the change of serum VEGF-D levels before and after treatment with sirolimus. The study group included 66 patients with LAM (47 definite LAM and 19 probable LAM based on European Respiratory Society guidelines), 14 patients with other polycystic lung diseases, and 20 healthy female controls. Serum VEGF-D levels were quantified by enzyme-linked immunoassay (ELISA). Serum VEGF-D levels were significantly increased in definite LAM patients compared with healthy controls (3890.3±373.3 pg/ml vs. 413.3±33.2 pg/ml, p<0.05). The optimal cutoff point for LAM diagnosis was 692.5 pg/ml with sensitivity of 97.9% and specificity of 100%. In probable LAM patients, serum VEGF-D levels were all greater than 692.5 pg/ml. Serum VEGF-D levels were significantly increased in definite LAM patients who had chylothorax compared with those without chylothorax (5153.9±598.3 pg/ml vs. 2869.8±372.8 pg/ml, p<0.05). But serum VEGF-D levels in LAM patients with/without pneumothorax, AML, and lymphangioleiomyomas were not significantly changed. Serum VEGF-D levels in definite LAM patients and patients with other cystic lung diseases were 3890.3±373.3 pg/ml and 412.6±27.5 pg/ml, respectively (p <0.05). We determined an optimal cutoff value of 688.5pg/ml, resulting in sensitivity of 97.9% and specificity of 100%. Following a median of 12-month treatment with sirolimus, serum VEGF-D levels decreased from 3135.0±909.4 pg/ml to 1731.8±621.2 pg/ml and symptoms improved. Our study found that serum VEGF-D levels were significantly higher in LAM patients compared with healthy controls and patients with other polycystic lung diseases and that the levels were further increased when complicated by chylothorax. Serum VEGF-D levels may be useful for diagnosis and differential diagnosis with high specificity and sensitivity as well as for following treatment response with sirolimus.