By labeling a receptor highly expressed by cancer cells with a fluorescent marker, ovarian tumors can be directly visualized during surgery. These results, published online this week in Nature Medicine, could allow physicians to track the spread of cancer cells with remarkable detail.

During cancer surgery, it is not always easy for doctors to determine the borders of the tumour, a limitation that can often result in relapse from the regrowth of cancer cells that were not removed during the operation. As ovarian cancer cells highly express the folate receptor, Gooitzen van Dam and his colleagues coupled folate to a fluorescent label and administered it to a small group of women during ovarian-cancer surgery trying to visualize the tumours in real time during the operation.

The team found that the compound was safe to patients and enabled surgeons to visualize the cancer cells, and precisely determine tumour stage and extent of spread/dispersion. Future studies with larger patient cohorts will help determine in greater detail the diagnostic value of this approach in terms of its accuracy and sensitivity.