MRI scans accurately spot spread of cancer: study

CHICAGO (Reuters) - A whole body MRI scan accurately detected breast tumors that had spread to the bone, even when there were no symptoms, offering a safe way to check patients, Indian researchers said on Thursday.

They said whole body magnetic resonance imaging or MRI -- which uses powerful magnets to create an image of the body -- should be the method of choice for checking to see if breast cancer has spread.

"When we use whole body MRI, it is a non-radiating tool. You are not giving radiation, which can be carcinogenic for the patient, and you are following them up very effectively," Dr. Joshita Singh of the Deenanath Mangeshkar Hospital and Research Center in Pune, India, who led the study, said in a telephone interview.

Singh, who presented her findings at the American Roentgen Ray Society meeting in San Diego, said whole body MRI would be helpful both in staging patients -- to determine the extent of the cancer and the best treatment approach -- and to track the effectiveness of treatments, without adding to a patient's cancer risk.

"It is important that we detect metastases early in order to ensure the patient is getting the appropriate treatment. This study shows that whole body MRI can accomplish this task," Singh said in a statement.

Radiation exposure from more conventional imaging such as computed tomography or CT scans became a major concern in October after more than 200 patients were exposed to potentially toxic doses of radiation during CT scans at Cedars-Sinai Medical Center in Los Angeles.

Imaging tools commonly used to detect breast cancer include PET/CT, a combination of positron emission tomography and a CT scan, chest X-rays, bone scans, and ultrasound of the abdomen and pelvis.

Singh did head to toe MRI scans on 99 patients with breast cancer.

They continued to follow these patients for clinical signs that the cancer had spread. They found MRI accurately showed that 47 patients had cancer that had spread, while 52 were negative.

In many cases where the cancer had spread, the whole body MRI spotted it before any symptoms appeared, Singh said.

(Editing by Maggie Fox and Bill Trott)