Pre-op MRI of margins predicts rectal cancer outcomes

(HealthDay)—Preoperative high-resolution magnetic resonance imaging (MRI) assessment of circumferential resection margin (CRM) status predicts survival and other disease progression outcomes in patients with rectal cancer, according to a study published online Nov. 25 in the Journal of Clinical Oncology.

Fiona G.M. Taylor, from Mayday University Hospital in Croydon, U.K., and colleagues conducted a follow-up study in 374 patients with rectal cancer. Preoperative high-resolution pelvic MRIs were used to assess CRM, and the relationship of MRI assessment and outcomes were evaluated.

The researchers found that five-year overall survival (OS) was 62.2 percent in patients with MRI-clear CRM compared to 42.2 percent in patients with MRI-involved CRM (hazard ratio, 1.97). Disease-free survival (DFS) at five years was 67.2 percent for MRI-clear CRM versus 47.3 percent for MRI-involved CRM (hazard ratio, 1.65). For MRI-involved CRM, local recurrence (LR) was 3.50. In multivariate analysis, MRI-involved CRM was the only preoperative staging parameter that remained significant for OS, DFS, and LR.

"High-resolution MRI preoperative assessment of CRM status is superior to American Joint Committee on Cancer TNM-based criteria for assessing risk of LR, DFS, and OS," the authors write.