From Complexity to Simplicity: Best Level of Evidence for Metastatic Colorectal Cancer
KO Lam
Hong Kong J Radiol 2013;16(Suppl):S9-16
Simplicity is enormously complex in the treatment of metastatic colorectal cancer. In terms of survival, life expectancy of patients with metastatic colorectal cancer improved substantially from 3 to 6 months in the 1980s when only 5-fluorouracil was available, to more than 20 months today with the availability of various new chemotherapeutic and targeted agents. The use of chemotherapeutic agents — including fluoropyrimidines, irinotecan, and oxaliplatin — has been refined through decades of clinical experience. Maximal exposure, irrespective of sequence, is simply the principle of treating patients through progression with chemotherapy. Targeted therapy has emerged in the past decade, and adds complexity to the treatment principle: survival benefit has been shown with both anti–vascular endothelial growth factor and anti–epidermal growth factor receptor antibodies in individual lines of treatment, but controversy exists as to the best sequence of application. Adding to this complexity, evidence continues to evolve for the predictive value of various key biomarkers as well as the development of new agents, including aflibercept and regorafenib. In this review, the best level of evidence and a simple, yet practical, strategy will be discussed for maximising the overall survival of patients.
中文摘要
從複雜到簡單：轉移性結直腸癌的最佳證據
林嘉安
要簡單地治療轉移性結直腸癌其實是相當複雜的。上世紀80年代治療轉移性結直腸癌的藥物只有5-氟尿嘧啶，當時患者的壽命一般約為3至6個月，直至現在因各種新的化療和靶向藥物的出現，令患者生存期大幅提高至20個月以上。經過數十年的臨床經驗，化療藥物（包括氟尿嘧啶、伊立替康和奧沙利鉑）的使用已得到完善。化療的主要原則簡單來說是在癌症的不同階段中，不論藥物使用的先後次序，盡量讓患者接受到各種化療藥物。靶向治療早在過去的十年經已出現，它增加了治療原則的複雜性：在各種治療線上出現的抗血管內皮生長因子和抗表皮生長因子受體抗體經已證明它們有助延長生存期，可是對治療的最佳次序仍存在爭議。同時，各種關鍵生物標誌物的預測值，以及新的藥物如aflibercept和regorafenib，亦增加了治療的複雜性。本文會討論最佳的研究證據，以及既簡單又實用的策略來把患者的總生存期延至最長。