Effects of Adjuvant Radiation Therapy and Chemotherapy Following Curative Surgery in Locally Advanced Rectal Cancer / 대한치료방사선과학회지

ABSTRACT

PURPOSE: To evaluate the effect of postoperative adjuvant radiation therapy and chemotherapy on the survival, pattern of failure and complication for locally advanced rectal carcinoma MATERIALS AND METHODS: From October 1992 to September 1995, twenty eight patients with rectal carcinoma were treated by postoperative adjuvant radiation therapy and chemotherapy. Radiation therapy was delivered with 6MV and 15MV linear accelerator, 180cGy fractions 5 day per week. Total radiation doses were 5040cGy in B2+3 and 5580cGy in C2+3. Within 4 weeks after radical surgery, 5-FU(400mg/m2/day) and Leucovorin(20mg/m2/day) were administered by intravenous injection for 4 days during the first and fifth week of radiation therapy. The median follow up was 19 months with a range 2 to 47 months. RESULTS: The 2 year overall survival and disease free survival rates were 78.6% and 70.8%, respectively. The 2 year overall survival was 93.0% in B2+3 and 76.2% in C2+3(p=0.11). The 2 year disease free survival was 79.4% in B2+3 and 69.2% in C2+3(p=0.13). The overall failure rate was 21.4%(6/28) including 10.7%(3/28) locoregional recurrence, 3.6%(1/28) distant metastasis and 7.1%(2/28) locoregional recurrence with distant metastasis. The overall locoregional recurrence rate was 17.9%(5/28). The 2 year locoregional recurrence rates were 13.3%(2/15) and 23.1%(3/13) for respectively for B2+3 and C2+3. The difference between the locoregional recurrence of B2+3 and C2+3 patients was not significant(p=0.07). Complications developed in 13 patients(46.4%), including 8 dermatitis, 7 loose stool, 6 leukopenia, 4 tenesmus, 2 diarrhea. In Univariate analysis, there was no statistically significant factor except for tumor grade in locoregional recurrence, disease free survival and overall survival rate(p=0.04, 0.05, 0.04). CONCLUSION: This study suggests that postoperative adjuvant radiation therapy and chemotherapy is effective in patients with locally advanced rectal cancer. Therefore these results need to be confirmed with a long term follow-up and larger number of patients with the further clinical trials including prospective controlled studies.