The aim of the present single-center retrospective study was to investigate the discrimination of malignant transformation from ovarian endometrioma (OE) using a near-infrared approach ex vivo. Cystic fluid samples were collected from patients with OE (n=34) and endometriosis-associated ovarian cancer (EAOC) (n=12). The light reflected from each sample of cystic fluid [change in luminance, Δl (cd/m2) = background luminance-cystic fluid luminance at 800 nm] was spectrally measured by a near-infrared CCD camera with band-path filter (800 nm). The Δl in EAOC was significantly lower compared with that in OE. On regression analysis, a positive correlation was observed between the Δl and Hb level in the cystic fluid, and this association was exponential. The diagnostic sensitivity and specificity of Δl was 83.3 and 94.1% at the cutoff value of 21.5 cd/m2, with an area under the ROC curve of 0.897. The present ex vivo study potentially provides a powerful near-infrared approach for quantitative discrimination between EAOC and benign OE, with high sensitivity and specificity, which may have clinical applications.
Keywords: endometriosis; malignant transformation; near infrared; ovarian cancer.