CHICAGO—A new study suggests that whole-body PET/CT imaging may be more useful than whole-body MRI for determining the extent a tumor has spread, according to an article in the December 24/31 issue of The Journal of the American Medical Association (JAMA).

In malignant diseases, therapeutic options as well as the patients' prognoses strongly depend on the tumor stage, according to background information in the article. Thus, accurate tumor staging encompassing the entire body is of essential importance. Magnetic resonance imaging (MRI) and a combined modality including positron emission tomography (PET) and computed tomography (CT) provide means for whole-body tumor staging in a single session. In contrast to MRI, which is mainly focused on the assessment of morphological (structural) characteristics of tissue, glucose analog [18F]-fluorodeoxyglucose-positron emission tomography (FDG-PET) provides functional information on tumor metabolism. The functional data available in whole-body scans complement morphological imaging for staging different malignancies.

PET is a medical imaging technique in which a radioactive 'tracer' is injected into a patient to help determine activity of a certain area of the body. CT imaging is the process of using digital processing to generate a three-dimensional image of an internal section of the body from a series of two-dimensional x-ray images. MRI involves application of an external magnetic field to produce three-dimensional images of body tissues.

Gerald Antoch, M.D., of the University Hospital Essen, Germany, and colleagues conducted a study to determine the staging accuracies of whole-body PET/CT and whole-body MRI for different malignant diseases and to compare these 2 new imaging tools.

The study included 98 patients (mean age 58 years; range, 27-94 years) with various cancers who underwent back-to-back whole-body PET/CT and whole-body MRI for tumor staging. The study was conducted at a university hospital from December 2001 through October 2002 and had a mean follow-up of 273 days (range, 75-515 days). The images were evaluated by 2 different teams. The diagnostic accuracies of the 2 imaging procedures were compared.

The researchers found that of the 98 patients, the overall primary tumor, regional lymph nodes, and distant metastasis (TNM) stage was correctly determined in 75 with PET/CT (77 percent) and in 53 with MRI (54 percent). "Compared with MRI, PET/CT had a direct impact on patient management in 12 patients. Results from MRI changed the therapy regimen in 2 patients compared with PET/CT. Separate assessment of [tumor]-stage (with pathological verification) in 46 patients revealed PET/CT to be accurate in 37 (80 percent) and MRI to be accurate in 24 (52 percent). Of 98 patients, [lymph node]-stage was correctly determined in 91 patients with PET/CT (93 percent) and in 77 patients with MRI (79 percent). Both imaging procedures showed a similar performance in detecting distant metastases," the authors write.

CHICAGO—Improving triage in hospitals and dissemination of information to the public helped bring a rapid resolution to the spread of severe acute respiratory syndrome (SARS) in Beijing in early 2003, according to an article in the December 24/31 issue of The Journal of the American Medical Association (JAMA).

Beijing, China, experienced the largest outbreak of SARS in the world with a total of 2,521 reported probable cases, according to background information in the article. The outbreak began March 5, 2003, with the importation of several cases among travelers from other SARS-affected areas and soon accelerated as multiple SARS cases occurred in health care facilities, peaking in late April when more than 100 new patients with SARS were being hospitalized daily. During the first week of May, the number of new cases dropped steeply and then declined steadily during the next few weeks, with the onset of the last probable case on May 29, 2003. The onset of the last case occurred only 6 weeks after the peak of the outbreak.

Xinghuo Pang, M.D., of the Beijing Center for Disease Prevention and Control, and colleagues evaluated the measures taken to rapidly control the SARS outbreak in Beijing and assess the effectiveness of some of these measures. The researchers reviewed data from standardized surveillance forms from SARS cases (2,521 probable cases) and their close contacts observed in Beijing between March 5, 2003, and May 29, 2003. Procedures implemented by health authorities were investigated through review of official documents and discussions with public health officials.

The researchers found that healthcare worker training in use of personal protective equipment and management of patients with SARS and establishing fever clinics and designated SARS wards in hospitals predated the steepest decline in cases. During the outbreak, 30,178 persons were quarantined. Among 2,195 quarantined close contacts in 5 districts, the attack rate was 6.3 percent, with a range of 15.4 percent among spouses to 0.36 percent among work and school contacts. The attack rate among quarantined household members increased with age from 5.0 percent in children younger than 10 years to 27.6 percent in adults aged 60 to 69 years. Among almost 14 million people screened for fever at the airport, train stations, and roadside checkpoints, only 12 were found to have probable SARS. The national and municipal governments held 13 press conferences about SARS. The time lag between illness onset and hospitalization decreased from a median of 5 to 6 days on or before April 20, 2003, the day the outbreak was announced to the public, to 2 days after April 20.

CHICAGO— A preliminary study suggests that use of a combination of corticosteroids and interferon may have a role in treatment of severe acute respiratory syndrome (SARS), according to an article in the December 24/31 issue of The Journal of the American Medical Association (JAMA).

According to background information in the article, SARS is characterized by fever, lower respiratory tract symptoms, and abnormal findings on chest x-ray. As of September 26, 2003, the World Health Organization has recorded 8,098 SARS cases and 774 SARS-related deaths from 27 countries. Treatment for SARS has included antibiotic therapy, corticosteroids and other drug therapies, but there is little compelling evidence that these strategies improve outcome. A group of drugs called interferons inhibit viral infections by boosting the body's immune response. In laboratory experiments, interferons were effective in inhibiting a strain of a SARS-related virus.

Mona R. Loutfy, M.D., M.P.H., of the North York General Hospital, Toronto, Ontario, and colleagues conducted a study between April 11 and May 30, 2003, to assess the use of corticosteroids vs. corticosteroids plus subcutaneous interferon alfacon-1 in 22 patients diagnosed as having probable SARS.

Thirteen patients were treated with corticosteroids alone and nine patients were treated with corticosteroids plus interferon alfacon-1. The patients included 16 women and 6 men ranging in age from 16 to 86 years.

The researchers found that the resolution of fever was similar between the two treatment groups. Of the 13 patients treated with corticosteroids alone, 5 (38.5 percent) were transferred to the intensive care unit, 3 (23.1 percent) required intubation and mechanical ventilation, and 1 (7.7 percent) died. Of the nine patients in the interferon alfacon-1 treatment group, 3 (33.3 percent) were transferred to the intensive care unit, 1 (11.1 percent) required intubation and mechanical ventilation, and none died.

The researchers also found that the interferon alfacon-1 group experienced a shorter time to resolution of chest x-ray abnormalities, and required supplemental oxygen for a shorter period of time.

"These preliminary findings suggest that treatment with interferon alfacon-1 and steroids was associated with more rapid resolution of radiographic lung abnormalities and better oxygen saturation levels than treatment with corticosteroids alone," write the authors.

"SARS CONTAINED BY OLD FASHIONED TECHNIQUES"