Locally Advanced Rectal Carcinoma : Curative Surgery Alone vs. Postoperative Radiotherapy and Chemotherapy

국소적으로 진행된 직장암에 대한 근치적 수술 단독 치료군과 수술후 보조적 방사선 및 항암화학요법 병행군의 치료결과 분석

Purpose : To evaluate the effects of postoperative radiotherapy and chemotherapy on the pattern of failure and survival for locally advanced rectal carcinoma, we analyzed the two groups of patients who received curative resection only and who received postoperative radiochemotherapy retro-spectively. Materials and Methods : From June 1989 to December 1992, ninety nine patients with rectal cancer were treated by curative resection and staged as B2-3 or C. Group I(25) patients received curative resection only and group II(74) patients postoperative adjuvant therapy. Postoperative adiuvant group received radiation therapy (4500cGy/25fx to whole pelvis) with 5-FU (500mg/$m^2$, day 1-3 IV infusion) as radiosensitizer and maintenance chemotherapy with 5-FU(400mg/$m^2$ for 5 days) and leucovorin (20mg/m^2$ for 5 days) for 6 cycles. Results : The patients in group I and group II were comparable in terms of age sex, performance status, but in group II $74{\%}$ of patients showed stage C compared with $56{\%}$ of group I. All patients were followed from 6 to 60 months with a median follow up of 29 months. Three year overall survival rates and disease free survival rates were $68\%,\;64\%$ respectively in group I and $64\%,\;61\%$, respectively in group II. There was no statistical difference between the two treatment groups in overall survival rate and disease free survival rate. Local recurrences occurred in $28{\%}$ of group I, $21{\%}$ of group II (p>.05) and distant metastases occurred in $20{\%}$ of group I, $27{\%}$ of group II(p>.05). The prognostic value of several variables other than treatment modality was assessed. In multivariate analysis for prognostic factors stage and histologic grade showed statistically significant effect on local recurrences and lymphatic or vessel invasion on distant metastasis. Conclusion : This retrospective study showed no statistical difference between two groups on the pattern of failure and survival. But considering that group II had more advanced stage and poor prognostic factors than group I, postoperative adjuvant radiochemotherapy improves the results for locally advanced rectal carcinoma as compared with curative surgery alone.