High-spatial-resolution signal enhancement ratio (SER) imaging may improve prediction for patients at high risk for disease recurrence and death, according to a study in the July issue of Radiology.
Ka-Loh Li, PhD, from the department of radiology at the University of California, San Francisco, and colleagues sought to retrospectively evaluate high-spatial-resolution SER imaging for the prediction of disease recurrence in patients with breast cancer, who underwent preoperative MRI.
From 1995 to 2002, the researchers acquired gadolinium-enhanced MRI data with a three time point high-resolution method in women undergoing neoadjuvant therapy for invasive breast cancers. Forty-eight women (mean age, 49.1 years) were divided into recurrence-free or recurrence groups, according to the authors.
The investigators calculated the breast tumor volume from the number of voxels with SER values above a threshold corresponding to the upper limit of mean redistribution rate constant in benign tumors (0.88 minutes) and the volume of cancerous breast tissue infiltrating into the parenchyma were important predictors of disease recurrence.
Li and colleagues found that 75 percent of patients with recurrence and identified 100 percent of deceased patients as being at high risk for recurrence. They said that 30 percent of patients with recurrence and identified 67 percent of deceased patients as having high risk before chemotherapy.
The researchers found that no patients in the recurrence-free group were misidentified as likely to have recurrence. All three prechemotherapy parameters (total tumor volume, tumor volumes with high and low SER) and the postchemotherapy tumor volume with high SER were significantly different between the two groups. The investigators found that the multivariate Cox proportional hazards regression showed that, of the three prechemotherapy covariates, only the low SER and high SER tumor volumes were significant and independent predictors of tumor recurrence.
Tumor volume with high SER was the only significant postchemotherapy covariate predictor, according to the authors.
Li and colleagues concluded that “high-spatial-resolution SER imaging may improve prediction for patients at high risk for disease recurrence and death.”