Predictive factors of regresion grade in patients with locally advanced rectal cancer treated with preoperative radiotherapy and capecitabine

Abstract

15081 Background: the aim of this study was to look for predictive factors of response in our series of patient treated at our institution with preoperative radiotherapy and capecitabine between 2003 to 2007. Methods: Seventy-eight patients with locally advanced rectal carcinoma (T3/T4 or N+) received 3D-radiotherapy (50,4–54Gy/28–30fractions) and chemotherapy with capecitabine (825mg/m2/12h on a continuous form). TME was performed 6–8 weeks after the end of the treatment. Results: There was 49 male and 29 female. Mean age 61,5 (range 26–85). ECOG 0:44p, 1: 33p, 2: 1p. Clinical stage (determined by EUS plus CT and/or MRI): cT2N1 1p, cT3N0 30p, cT3N1 38p, cT3N2 6p, cT4N1 2p, cT4N2 1p. Tumor location were inferior in 33p, medium in 37p and superior in 8p. Mean CEA level 17 (range 1–356). Radiotherapy dose was 50,4Gy in 45p and 54,4 in 33p. Surgery consisted of low anterior resection in 56p, and abdominoperineal resection in 20p (two patients were R2). Tumor downstaging was observed in 55p (70,5%), including 13p with complete pathological response (16,7%) and 19p with only microfoci of tumor remaining (24,4%). 66,7% received adjuvant chemotherapy. Main adverse event (CTC): diarrhea G3–4: 25,6%, skin G2–3: 9%, hemathologic G2–3: 5,4% and hand-foot syndrome 5%. Predictive factor analysis: only CEA level and clinical tumor staging showed significant correlation with tumor response. Conclusions: Preoperative chemoradiotherapy with capecitabine is an excellent tolerated regimen with high probability of tumor downstaging. Our results showed that CEA level and clinical tumor staging with EUS and CT/MRI were a significant correlation with grade of regresion. No significant financial relationships to disclose.