目的：本研究乃針對直腸癌病患比較兩種術前輔助治療結果，並針對達到完全緩解的病人分析且評估進行後續標準手術之重要性。材料與方法：從1999年3月至2007年12月，本回顧性研究包括417例新診斷無遠端轉移的直腸癌病患，比較術前短程放射治療（RT）或長程放化療（CCRT）的治療效果。術前輔助治療後是否達到完全緩解的狀態由手術標本或切片證實。結果：平均追蹤時間為30.9個月。進行術前輔助治療後，在短程放射治療組（RT）達到完全緩解者有5例（2%）；而在長程合併放射化學療法組（CCRT）有34例（17%），統計上達顯著意義（p<0.001）。五年存活率為在短程放射治療組（RT）為59%，長程合併放射化學療法組（CCRT）為49%。針對達到完全緩解的族群進行後續的分析，完成術前輔助治療後仍接受原訂標準主要手術者具有最佳存活率，統計上顯著優於只接受局部切除或局部切片者（p=0.04）。長程合併放射化學療法組（CCRT）有較多的病人只接受局部切除或觀察（50例，25.5%），相對應在短程放射治療組（RT）僅7例（3%）。若統計分析只針對確實有接受後續標準主要手術者，發現兩種術前輔助治療組別間並無存活率上的差異（p=0.657）。結論：與短程放射治療組（RT）相比，長程合併放射化學療組（CCRT）有較高的比率達到病理緩解。長程合併放射化學療組（CCRT）卻有更高的比例變更後續的標準手術治療策略。若針對確實接受後續標準主要手術的病人族群來分析，發現兩種術前輔助治療組別間並無存活率的差異。本回性研究清楚顯示患者依從性的重要性和執行後續標準主要手術的影響力。

Purpose: The aim of the present study was to evaluate the incidence of complete tumor response (CR) achieved following two different neoadjuvant modalities and the importance of major surgery after neoadjuvant treatment. Materials and Method: Between March 1999 and December 2007, this is retrospective study included 417 patients with newly-diagnosed dissemination-naive rectal cancer, treated with pre-operative short-course radiotherapy (RT) or long-course chemoradiotherapy (CCRT). The status of tumor response was confirmed by biopsy or surgery. Result: Median follow-up was 30.9 months. After neoadjuvant treatment, CR was documented in 5 of 221 patients (2%) in the short-course RT group, and 34 of 198 (17%) in the long-course CCRT group (p < 0.001). The 5-year overall survival rate was 59% in short-course RT group and 49% in long-course CCRT group respectively. Focusing on the subgroup that was documented to achieve pathological tumor complete response (pCR), the survival benefit was most clear in those who received major surgery after neoadjuvant treatment rather than local excision only. There were more patients receiving merely local excision or observation in CCRT group (n= 50, 25.5%) than in RT alone group (n= 7, 3%). In the subgroup analysis specific to the patients who underwent standard major surgery after neoadjuvant treatment, no statistically significant difference in terms of overall survival was found between these two different neoadjuvant settings (p= 0.657). Conclusions: Subgroup analysis pertaining to patients who actually received major surgery after neoadjuvant treatment showed that there was no significant difference with regard to overall survival rates in these two neoadjuvant settings. The importance of patient compliance and performing major surgery after neoadjuvant treatment was clearly demonstrated in this retrospective study.