Assessment of Long-term Rectal Function in Patients Who Received Pelvic Radiation Therapy, Pooled Data from Two Prospective NCCTG Trials (969256 and N00CA)

Results: Data from 252 patients were available for analysis. The total BFQ score was higher at both 12 months (p \ 0.0001) and 24 months (p = 0.0007) than at baseline, supporting poorer bowel function. Symptoms occurring in .20% of patients at 12 months were urgency, stool versus gas confusion, clustering of bowel movements, and cramping. Forty-nine percent of patients had no reported bowel symptoms at baseline (BFQ of 0), 36% at 12 months, and 39% at 24 months. Sixty-seven percent of patients had BFQ scores of 0-1 at baseline, 58% at 12 months, and 57% at 24 months. Further, there were more patients with BFQ scores of 5-9 at 12 months (12%) and 24 months (10%) than at baseline (2%). This significant increase in BFQ scores in a small number of patients may account for most of the decline in bowel function in this patient population. Factors that were associated with worse long term bowel function were female sex, rectal or gynecologic location of primary, prior anterior resection of the rectum, and 5-FU chemotherapy. Patients with grade $2 acute toxicity had worse 24 month bowel function, particularly frequency, stool versus gas confusion, liquid stools, and cramping, compared to patients with grade \2 toxicity (p values 0.0008 to 0.02). QOL was not significantly different from baseline at 12 or 24 months despite worsening bowel function over that time. Conclusions:Radiationtherapyto the pelviswas associatedwith measuresof adversebowelfunction. However, longterm decline inbowelfunctionwasnotassociatedwithdecreasedQOL.Asevidencedbythepercentageofpatientswithonly0or1bowelsymp