Modern approaches to noninvasive diagnosis of malignant transformation of endometriosis

Endometriosis-associated ovarian cancer (EAOC) is a rare entity and has highly variable morphological presentations. Mural nodules can be seen in EAOC and benign ovarian endometrioma (OE), which causes a diagnostic dilemma. The differential diagnosis between early-stage EAOC with predominantly cystic appearances and benign OE remains a challenge for physicians. This study will summarize recent knowledge of diagnosis of malignant transformation of endometriosis that have been studied through an innovative approach based on a wide array of novel technologies. Using PubMed database, we focused on the biochemical and technical advancement in the differential diagnosis of benign and malignant endometriosis. Compared with the subjects with benign OE, cyst fluid hemoglobin and iron-related compounds levels were significantly lower in patients with EAOC. This observation opens up the possibility of early diagnosis before morphological variations are captured through ultrasonographic and magnetic resonance (MR) imaging diagnosis. The metallobiology technology offers one solution to this challenge. We discuss the noninvasive diagnosis of EAOC via various imaging methods, including electronic absorption spectroscopy, near infrared approach and MR transverse relaxometry. Special emphasis is given to recent advances in the noninvasive imaging modalities.