Changing Clinical Practice for the Better
New Study Suggests Reducing CT Imaging in Pediatric Cancer Patients With Initial Febrile Neutropenia
Febrile neutropenia, or FN, occurs in patients with compromised immune systems. In cancer patients, chemotherapy treatments reduce the normal number of cells that the body uses to fight infections, specifically bacteria-fighting cells called neutrophils.
"When patients have a very low neutrophil count, it indicates they are at higher risk of getting an infection," explains Dr. Agrawal. "FN occurs when kids get a fever at the same time their neutrophil count is low, and it suggests the potential for an active, serious infection."
When FN occurs, patients are generally hospitalized so that the type of infection can be determined and treated. But figuring out what kind of infection a patient might have is not necessarily that easy.
"In some kids, they have a short period of time with a fever, and then it resolves and they go home. In other kids, the fever persists longer and we are able to find a source for the infection, such as bacteria in the blood for example," Dr. Agrawal says. "In a large portion of kids, however, the fever continues with no known source."In those cases, pediatric oncologists generally treat patients with empiric antibiotics and antifungals. In addition, with continued FN for five to seven days, it has become standard practice to perform CT images on the sinuses, chest, abdomen and pelvis to look for evidence of occult infections. However, the risk of radiation exposure in children, and children being treated for cancer in particular, has come under more scrutiny as cancer treatments have become more successful and cancer patients are living longer.
In the study, although there were positive findings in 18, 12, and 25 percent of initial CT scans of the chest, abdomen, and sinuses, these positive findings rarely resulted in changes in therapy. In fact, alteration in therapy at this stage was incredibly rare, only occurring in two of the initial scans – or 0.8 percent of all the scans that were done.
Patients that were asymptomatic but were still scanned due to the length of their FN may have had positive findings on CT but due to the use of empiric antibiotics and antifungals, these findings were generally not significant, meaning they did not affect how the patient was treated for the FN.
"The study demonstrated that doing a full series of scans – sinuses, chest, abdomen and pelvis – did not have much utility in the setting of an initial episode of FN. Of all the scans, the chest seemed to be the one area that might still be of benefit. Still, eliminating the standard CT of the sinuses, abdomen, and pelvis at this stage would be a significant reduction in radiation for kids with prolonged FN," says Dr. Agrawal.Dr. Agrawal is hopeful that the results of the study will help guide pediatric oncologists treating cancer patients from here on out.
Tuesday, May 17, 2011 8:19 AM