[The Instructions to Authors state no abstract is required for a Research Letter but the submission sysem demands one, so this text is included.] In order to assess whether measuring HE4 might add to the performance of CA125 in diagnosing ovarian cancer, we measured both markers in 33 individuals with elevated CA125. We found that HE4 elevated above 150 pmol/l was present in all 9 cases of ovarian cancer and in the single case of pancreatic cancer. HE4 levels below 77pmol/l seen in 16 cases were associated with non-malignant gynaecological conditions and with there being no identified cause for elevated CA125. Two cases with HE4 between 77 and 149 pmol/l had no gynaecological conditions and 2 had no an identifiable cause. Measuring both markers could lead to improved sensitivity and specificity of the initial diagnostic step.