Purpose: To evaluate the blood flow changes and their relationships to microvessel density (MVD) and thrombospondin-1 (TSP-1) by transvaginal colour Doppler sonography (TV-CDS) in the ovarian interstitium to predict ovarian interstitial microvascular injury in the pathological process of ovarian endometrial cysts (OEC).
Methods: TV-CDS was preoperatively performed to detect blood flow changes in 60 patients with 76 ovarian endometrioid cysts, and flow classification and resistance indices (RI) values were recorded for analysis. Ovarian interstitial specimens with blood flow signals were collected for postoperative pathologic examination. TSP-1 protein was evaluated by immunohistochemistry and Western blot, TSP-1 mRNA by reverse transcriptase polymerase chain reaction, microvessels by CD34 antibody, and MVD by image analysis. Thirty age-matched patients with benign ovarian tumours served as controls.
Results: Blood flow, most of star-shaped, within ovarian interstitial arteries in the OEC group was diminished; however, arterial spectra exhibited a high-resistance flow manifesting a significantly higher RI compared with that of the control group (P < 0.01). In ovarian interstitial specimens, there were significantly (P < 0.01) lower CD34-MVD and higher TSP-1 protein and mRNA in the OEC group than in the controls. CD34-MVD and TSP-1 showed remarkably negative correlation (rs = -0.76, P < 0.01). RI values correlated negatively with MVD values (rs = -0.91, P < 0.01), but positively with TSP-1 (rs = 0.81, P < 0.01), while flow classification correlated positively with MVD values (rs = 0.66, P < 0.01), but negatively with TSP-1 (rs = -0.54, P < 0.01).
Conclusions: Changes in CD34-MVD and TSP-1 reflected ovarian interstitial microvascular injury of OEC, pathologically supported the findings of blood flow changes within ovarian interstitial arteries, and prospectively predicted OEC-induced ovarian interstitial vessel injury. This has important clinical value: early treatment, instead of allowing the cyst to become bigger, is of great importance for OEC patients, because a greater number of functional tissue blood vessels would be destroyed as the disease progresses.