If an ovarian growth is found, blood tests may be done to measure certain protein markers in the blood. ROMA (Risk Of Ovarian Malignancy Algorithm) can be used to calculate estimated risk of epithelial ovarian cancer in both pre- and postmenopausal women based on CA125 and HE4 test values. Ovarian cancer is diagnosed with histologic analysis and includes immunohistochemistry (IHC) assays of a biopsy or surgical specimen. Tumors of varying subtypes often look similar, making it difficult to distinguish between them so IHC makes it possible to assess for markers associated with particular subtypes, to assist in a differential diagnosis.
Since the stage and grade of ovarian cancer will help guide treatment decisions, it is important that classification be reported as accurately as possible. There are generally four stages of ovarian cancer, referring to the size of a tumor and whether cancer cells have spread to other parts of the body. Tumour grade refers to how abnormal cancer cells look under a microscope, and may be classified as low-grade or high-grade based on a morphological assessment by a pathologist in the laboratory.