Cervical cancers that take up a lot of blood sugar, or glucose, are more resistant to treatment than those that are less glucose-hungry, according to research at Washington University School of Medicine in St. Louis.
The researchers also found that the high glucose-uptake tumors can be identified with PET scans, which are already routinely used to determine tumor size and lymph node involvement in cervical cancer patients.
PET scans monitor the amount of a radioactive glucose tracer absorbed by cells, so the brightness of the image reveals how much glucose a tumor takes up. The results of the research team's analysis indicate that PET scans can be used to better determine prognosis in cervical cancer patients.
"Cervical tumors vary more in their glucose uptake than other kinds of cancer, making glucose uptake a very useful indicator for cervical cancers," says Perry W. Grigsby, M.D., a radiation oncologist with the Siteman Cancer Center at Washington University School of Medicine and Barnes-Jewish Hospital. "We found that the tumors with higher uptake were associated with lower survival rates and lower disease-free survival rates."
In a report published in the April issue of Gynecological Oncology, the researchers summarized their findings for 96 cervical cancer patients who underwent PET scans before radiation and chemotherapy were initiated.
Analysis showed that 71 percent of patients whose tumors had a glucose uptake value below the median value of 10.2 survived five years without a recurrence of their disease. In contrast, 52 percent of those whose glucose uptake measured above 10.2 went for five years without a recurrence.
Since submitting their findings, the team has continued their investigation with additional patients, who now number near 250. The trend of lower five-year disease-free survival with higher tumor glucose uptake has been born out in the additional patients.
Further, the continuing study has clearly demonstrated that the overall (disease-free and disease-recurring) five-year survival rate was lower in the group of patients whose tumor glucose uptake was above the median of 10.2.