MUC16 and ovarian carcinoma: However, the symptoms — such as bloating and abdominal pain — are non-specific and, therefore, have relatively low positive predictive values for the disease.5,6 In 2011, the National Institute for Health and Care Excellence (NICE) advocated testing for the serum biomarker cancer antigen 125 (CA125) in women with symptoms of possible ovarian cancer in primary care.7 NICE recommended that women with an elevated CA125 (≥35 U/ml) should undergo ultrasound testing;7 however, they did not provide guidance on the follow-up or investigation of women with ‘normal’ (<35 U/ml) CA125 levels.