Tumor regression grade, circumferential resection margin predict survival in good, poor responders
FRIDAY, Sept. 2 (HealthDay News) -- Magnetic resonance imaging (MRI) assessment of tumor regression grade (TRG) and circumferential resection margin (CRM) can be used to predict survival for good and poor responders in rectal cancer, according to a study published online Aug. 29 in the Journal of Clinical Oncology.
Uday B. Patel, M.B.C.L.B., M.R.C.P., from the Royal Marsden Hospital in Sutton, U.K., and colleagues assessed MRI and pathologic staging by T, N, and CRM status after neoadjuvant therapy for rectal cancer in 111 patients. The patients were evaluated for response and TRG by MRI. Kaplan-Meier product-limit was used to predict overall survival (OS), and Cox proportional hazards models were used to assess correlations between staging of good and poor responders on MRI or pathology and survival outcomes.
The investigators found that the MRI-assessed TRG (mrTRG) hazard ratios (HRs) were independently significant for survival and disease-free survival (DFS) (HR, 4.40 and 3.28, respectively). Five-year survival and DFS for poor mrTRG were significantly lower (27 versus 72 percent and 31 versus 64 percent, respectively). Local recurrence (LR) was independently predicted by preoperative MRI-predicted CRM (HR, 4.25). Poor post-treatment pathologic T stage had a significantly lower five-year survival (39 versus 76 percent), DFS (38 versus 84 percent), and higher LR (27 versus 6 percent). For involved pathologic CRM, the five-year survival rate was significantly lower (30 versus 59 percent), as was DFS (28 versus 62 percent), and LR was significantly higher (56 versus 10 percent). Pathology node status was not predictive of outcomes.
"MRI assessment of TRG and CRM are imaging markers that predict survival outcomes for good and poor responders," the authors write.