Using a combination Positron Emission Tomography (PET) and computed tomography (CT) scanner, researchers monitored 50 patients undergoing treatment for high-grade soft tissue sarcomas. The patients were receiving neoadjuvant chemotherapy treatments to shrink their tumours prior to surgery. The study found that response could be determined about a week after the first dose of chemotherapy drugs. Typically, patients are scanned at about three months into chemotherapy to determine whether the treatment is working.
“The question was, how early could we pick up a response? We wanted to see if we could determine response after a single administration of chemotherapy,” said Fritz Eilber, senior author of the study. “There is no point in giving a patient a treatment that is not working. These treatments make patients very sick and have long-term serious side effects.”
For this study, Eilber and his team monitored the tumour’s metabolic function, or how much sugar was being consumed by the cancer cells. Because they are growing out of control, cancer cells use much more sugar than do normal cells, making them light up under PET scanning using a glucose uptake probe called FDG. In order to identify an effective response to treatment, researchers needed to see a 35 percent decrease in the tumour’s metabolic activity.
Of the 50 patients in the study, 28 did not respond and Eilber and his team knew within a week of their initial treatment. This allows the treatment course to be discontinued or changed to another more effective treatment, getting the patient to surgery more quickly.
Eilber and his team will continue to follow the patients and a clinical trial currently is underway based on the results of this study. Eilber believes it will help personalise treatment for each patient.
MEDICA.de; Source: University of California, Los Angeles (UCLA), Health Sciences