Some women have very aggressive forms of cancer

The cancers are the fourth and fifth most common amongst women in the UK.

A small group of women with both diseases will have particularly virulent forms, but it is hard to identify who they are.

Researchers writing, in The Lancet, claim the protein - L1 - will help detect the women at most risk.

The researchers, from the German Cancer Research Centre in Heidelberg, Germany, looked at whether the LI protein molecule, known to be involved in the spread of malignant tumours, could help identify which women were at risk.

It could be possible to detect this protein in blood Dr James Brenton, Cancer Research UK

They looked at 58 women with ovarian cancer and 72 with womb cancer and compared them with 65 with benign ovarian or uterine cancers and bowel or colon cancers.

It was found 46 women with ovarian cancer and 20 of those with uterine cancer had L1 positive tumours.

The survival time of patients with L1 positive tumours was shorter than for those with L1 negative tumours.

Evaluation

Dr Peter Altevogt, who led the research at the German Cancer Research Centre, Heidelberg, said: "Collectively, our results suggest that over-expression of L1 constitutes a new marker for ovarian and uterine carcinomas associated with poor clinical outcome.

"Well-designed prospective studies are needed to validate use of L1 expression in the classification and treatment of patients with ovarian and uterine carcinomas.

"L1-based diagnosis and prognosis could make an important contribution towards a better management and treatment of this disease."

Dr James Brenton, Cancer Research UK Senior Clinical Research Fellow at Addenbrooke's Hospital, Cambridge, told BBC News Online the research was still at a very early stage.

"L1 is promising as it could be possible to detect this protein in blood serum.

"But this needs to be evaluated with research on hundreds to thousands of people to show if it's an independent prognostic marker of cancer, which is not shown in this study."