The occurrence of metastasis is a frequent event in the natural history of colonic cancer. In 20 to 30% of cases, metastases are synchronous with the discovery of the primary tumor. Furthermore, 50% of patients operated on for colonic adenocarcinoma with lymph node metastases during their evolution. Highlighting metastases in the development of colon cancer leads to systematically raise the possibility of surgical resection. In case of non-resectable metastases, the proposed treatment of chemotherapy is justified if the condition is retained. This chemotherapy was the main objective to increase the life and especially life without symptoms. The data published in a recent meta-analysis shows that the achievement of chemotherapy increases by 50% survival at 1 year without deterioration of quality of life [1]. A second goal of treatment is to enable resection of metastases. This is rare in multicenter studies [2]. The goal of treatment is usually palliative and should be clearly explained to the patient. This objective is to palliative corollary notions of chronicity (of the disease and treatment) and very high probability of death from disease progression.
The development of treatment regimens in response to a specific methodology. Drugs or drug combinations are, firstly, as assessed by clinical phase II. In these studies, the toxicity is the primary endpoint, efficiency is a secondary criterion, usually summed up by the response rate (WHO criteria). The response rate is an intermediate criterion, reproducible, confirming the effectiveness of chemotherapy on tumor disease but it can not replace the main goal of treatment is life. The Phase II study is a step of selecting treatment regimens. In a second step, the patterns of the most promising phase II are compared with the reference scheme to try to show a survival advantage. These randomized prospective studies (Phase III) or their meta-analysis have the primary endpoint of the life and the secondary criteria of life without symptoms or progression-free life. For methodological reasons, only phase III trials and meta-analysis allows the rigorous comparison of the results of survival data, toxicity and quality of life.
The recent history of chemotherapy for colon cancer has experienced two major periods. The first of 1959 to early 90's considered the only drug considered potentially effective, 5 fluorouracil (5FU) and its various methods of administration and Biomodule. This period led to the development of several schemes of "reference" in different countries and continents. The second period began with the development of new drugs (irinotecan, oxaliplatin, raltitrexed) and caused a change in the therapeutic management with the demonstration of the effectiveness of second-line treatment [3].
In the first part, tells us, using the methodological tools of evidence-based medicine (evidence-based medicine, EBM) presented in the introduction, the evolution of treatment regimens for 10 years. In
a second part, we discuss the problems of choice between different patterns.
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